src/game.c

   1 // ============================================================================
   2 // Rocks'n'Diamonds - McDuffin Strikes Back!
   3 // ----------------------------------------------------------------------------
   4 // (c) 1995-2014 by Artsoft Entertainment
   5 //                  Holger Schemel
   6 //                  info@artsoft.org
   7 //                  https://www.artsoft.org/
   8 // ----------------------------------------------------------------------------
   9 // game.c
  10 // ============================================================================
  11
  12 #include "libgame/libgame.h"
  13
  14 #include "game.h"
  15 #include "init.h"
  16 #include "tools.h"
  17 #include "screens.h"
  18 #include "events.h"
  19 #include "files.h"
  20 #include "tape.h"
  21 #include "network.h"
  22 #include "anim.h"
  23
  24
  25 // DEBUG SETTINGS
  26 #define DEBUG_INIT_PLAYER       1
  27 #define DEBUG_PLAYER_ACTIONS    0
  28
  29 // EXPERIMENTAL STUFF
  30 #define USE_NEW_AMOEBA_CODE     FALSE
  31
  32 // EXPERIMENTAL STUFF
  33 #define USE_QUICKSAND_BD_ROCK_BUGFIX    0
  34 #define USE_QUICKSAND_IMPACT_BUGFIX     0
  35 #define USE_DELAYED_GFX_REDRAW          0
  36 #define USE_NEW_PLAYER_ASSIGNMENTS      1
  37
  38 #if USE_DELAYED_GFX_REDRAW
  39 #define TEST_DrawLevelField(x, y)                               \
  40         GfxRedraw[x][y] |= GFX_REDRAW_TILE
  41 #define TEST_DrawLevelFieldCrumbled(x, y)                       \
  42         GfxRedraw[x][y] |= GFX_REDRAW_TILE_CRUMBLED
  43 #define TEST_DrawLevelFieldCrumbledNeighbours(x, y)             \
  44         GfxRedraw[x][y] |= GFX_REDRAW_TILE_CRUMBLED_NEIGHBOURS
  45 #define TEST_DrawTwinkleOnField(x, y)                           \
  46         GfxRedraw[x][y] |= GFX_REDRAW_TILE_TWINKLED
  47 #else
  48 #define TEST_DrawLevelField(x, y)                               \
  49              DrawLevelField(x, y)
  50 #define TEST_DrawLevelFieldCrumbled(x, y)                       \
  51              DrawLevelFieldCrumbled(x, y)
  52 #define TEST_DrawLevelFieldCrumbledNeighbours(x, y)             \
  53              DrawLevelFieldCrumbledNeighbours(x, y)
  54 #define TEST_DrawTwinkleOnField(x, y)                           \
  55              DrawTwinkleOnField(x, y)
  56 #endif
  57
  58
  59 // for DigField()
  60 #define DF_NO_PUSH              0
  61 #define DF_DIG                  1
  62 #define DF_SNAP                 2
  63
  64 // for MovePlayer()
  65 #define MP_NO_ACTION            0
  66 #define MP_MOVING               1
  67 #define MP_ACTION               2
  68 #define MP_DONT_RUN_INTO        (MP_MOVING | MP_ACTION)
  69
  70 // for ScrollPlayer()
  71 #define SCROLL_INIT             0
  72 #define SCROLL_GO_ON            1
  73
  74 // for Bang()/Explode()
  75 #define EX_PHASE_START          0
  76 #define EX_TYPE_NONE            0
  77 #define EX_TYPE_NORMAL          (1 << 0)
  78 #define EX_TYPE_CENTER          (1 << 1)
  79 #define EX_TYPE_BORDER          (1 << 2)
  80 #define EX_TYPE_CROSS           (1 << 3)
  81 #define EX_TYPE_DYNA            (1 << 4)
  82 #define EX_TYPE_SINGLE_TILE     (EX_TYPE_CENTER | EX_TYPE_BORDER)
  83
  84 #define PANEL_OFF()             (game.panel.active == FALSE)
  85 #define PANEL_DEACTIVATED(p)    ((p)->x < 0 || (p)->y < 0 || PANEL_OFF())
  86 #define PANEL_XPOS(p)           (DX + ALIGNED_TEXT_XPOS(p))
  87 #define PANEL_YPOS(p)           (DY + ALIGNED_TEXT_YPOS(p))
  88
  89 // game panel display and control definitions
  90 #define GAME_PANEL_LEVEL_NUMBER                 0
  91 #define GAME_PANEL_GEMS                         1
  92 #define GAME_PANEL_INVENTORY_COUNT              2
  93 #define GAME_PANEL_INVENTORY_FIRST_1            3
  94 #define GAME_PANEL_INVENTORY_FIRST_2            4
  95 #define GAME_PANEL_INVENTORY_FIRST_3            5
  96 #define GAME_PANEL_INVENTORY_FIRST_4            6
  97 #define GAME_PANEL_INVENTORY_FIRST_5            7
  98 #define GAME_PANEL_INVENTORY_FIRST_6            8
  99 #define GAME_PANEL_INVENTORY_FIRST_7            9
 100 #define GAME_PANEL_INVENTORY_FIRST_8            10
 101 #define GAME_PANEL_INVENTORY_LAST_1             11
 102 #define GAME_PANEL_INVENTORY_LAST_2             12
 103 #define GAME_PANEL_INVENTORY_LAST_3             13
 104 #define GAME_PANEL_INVENTORY_LAST_4             14
 105 #define GAME_PANEL_INVENTORY_LAST_5             15
 106 #define GAME_PANEL_INVENTORY_LAST_6             16
 107 #define GAME_PANEL_INVENTORY_LAST_7             17
 108 #define GAME_PANEL_INVENTORY_LAST_8             18
 109 #define GAME_PANEL_KEY_1                        19
 110 #define GAME_PANEL_KEY_2                        20
 111 #define GAME_PANEL_KEY_3                        21
 112 #define GAME_PANEL_KEY_4                        22
 113 #define GAME_PANEL_KEY_5                        23
 114 #define GAME_PANEL_KEY_6                        24
 115 #define GAME_PANEL_KEY_7                        25
 116 #define GAME_PANEL_KEY_8                        26
 117 #define GAME_PANEL_KEY_WHITE                    27
 118 #define GAME_PANEL_KEY_WHITE_COUNT              28
 119 #define GAME_PANEL_SCORE                        29
 120 #define GAME_PANEL_HIGHSCORE                    30
 121 #define GAME_PANEL_TIME                         31
 122 #define GAME_PANEL_TIME_HH                      32
 123 #define GAME_PANEL_TIME_MM                      33
 124 #define GAME_PANEL_TIME_SS                      34
 125 #define GAME_PANEL_TIME_ANIM                    35
 126 #define GAME_PANEL_HEALTH                       36
 127 #define GAME_PANEL_HEALTH_ANIM                  37
 128 #define GAME_PANEL_FRAME                        38
 129 #define GAME_PANEL_SHIELD_NORMAL                39
 130 #define GAME_PANEL_SHIELD_NORMAL_TIME           40
 131 #define GAME_PANEL_SHIELD_DEADLY                41
 132 #define GAME_PANEL_SHIELD_DEADLY_TIME           42
 133 #define GAME_PANEL_EXIT                         43
 134 #define GAME_PANEL_EMC_MAGIC_BALL               44
 135 #define GAME_PANEL_EMC_MAGIC_BALL_SWITCH        45
 136 #define GAME_PANEL_LIGHT_SWITCH                 46
 137 #define GAME_PANEL_LIGHT_SWITCH_TIME            47
 138 #define GAME_PANEL_TIMEGATE_SWITCH              48
 139 #define GAME_PANEL_TIMEGATE_SWITCH_TIME         49
 140 #define GAME_PANEL_SWITCHGATE_SWITCH            50
 141 #define GAME_PANEL_EMC_LENSES                   51
 142 #define GAME_PANEL_EMC_LENSES_TIME              52
 143 #define GAME_PANEL_EMC_MAGNIFIER                53
 144 #define GAME_PANEL_EMC_MAGNIFIER_TIME           54
 145 #define GAME_PANEL_BALLOON_SWITCH               55
 146 #define GAME_PANEL_DYNABOMB_NUMBER              56
 147 #define GAME_PANEL_DYNABOMB_SIZE                57
 148 #define GAME_PANEL_DYNABOMB_POWER               58
 149 #define GAME_PANEL_PENGUINS                     59
 150 #define GAME_PANEL_SOKOBAN_OBJECTS              60
 151 #define GAME_PANEL_SOKOBAN_FIELDS               61
 152 #define GAME_PANEL_ROBOT_WHEEL                  62
 153 #define GAME_PANEL_CONVEYOR_BELT_1              63
 154 #define GAME_PANEL_CONVEYOR_BELT_2              64
 155 #define GAME_PANEL_CONVEYOR_BELT_3              65
 156 #define GAME_PANEL_CONVEYOR_BELT_4              66
 157 #define GAME_PANEL_CONVEYOR_BELT_1_SWITCH       67
 158 #define GAME_PANEL_CONVEYOR_BELT_2_SWITCH       68
 159 #define GAME_PANEL_CONVEYOR_BELT_3_SWITCH       69
 160 #define GAME_PANEL_CONVEYOR_BELT_4_SWITCH       70
 161 #define GAME_PANEL_MAGIC_WALL                   71
 162 #define GAME_PANEL_MAGIC_WALL_TIME              72
 163 #define GAME_PANEL_GRAVITY_STATE                73
 164 #define GAME_PANEL_GRAPHIC_1                    74
 165 #define GAME_PANEL_GRAPHIC_2                    75
 166 #define GAME_PANEL_GRAPHIC_3                    76
 167 #define GAME_PANEL_GRAPHIC_4                    77
 168 #define GAME_PANEL_GRAPHIC_5                    78
 169 #define GAME_PANEL_GRAPHIC_6                    79
 170 #define GAME_PANEL_GRAPHIC_7                    80
 171 #define GAME_PANEL_GRAPHIC_8                    81
 172 #define GAME_PANEL_ELEMENT_1                    82
 173 #define GAME_PANEL_ELEMENT_2                    83
 174 #define GAME_PANEL_ELEMENT_3                    84
 175 #define GAME_PANEL_ELEMENT_4                    85
 176 #define GAME_PANEL_ELEMENT_5                    86
 177 #define GAME_PANEL_ELEMENT_6                    87
 178 #define GAME_PANEL_ELEMENT_7                    88
 179 #define GAME_PANEL_ELEMENT_8                    89
 180 #define GAME_PANEL_ELEMENT_COUNT_1              90
 181 #define GAME_PANEL_ELEMENT_COUNT_2              91
 182 #define GAME_PANEL_ELEMENT_COUNT_3              92
 183 #define GAME_PANEL_ELEMENT_COUNT_4              93
 184 #define GAME_PANEL_ELEMENT_COUNT_5              94
 185 #define GAME_PANEL_ELEMENT_COUNT_6              95
 186 #define GAME_PANEL_ELEMENT_COUNT_7              96
 187 #define GAME_PANEL_ELEMENT_COUNT_8              97
 188 #define GAME_PANEL_CE_SCORE_1                   98
 189 #define GAME_PANEL_CE_SCORE_2                   99
 190 #define GAME_PANEL_CE_SCORE_3                   100
 191 #define GAME_PANEL_CE_SCORE_4                   101
 192 #define GAME_PANEL_CE_SCORE_5                   102
 193 #define GAME_PANEL_CE_SCORE_6                   103
 194 #define GAME_PANEL_CE_SCORE_7                   104
 195 #define GAME_PANEL_CE_SCORE_8                   105
 196 #define GAME_PANEL_CE_SCORE_1_ELEMENT           106
 197 #define GAME_PANEL_CE_SCORE_2_ELEMENT           107
 198 #define GAME_PANEL_CE_SCORE_3_ELEMENT           108
 199 #define GAME_PANEL_CE_SCORE_4_ELEMENT           109
 200 #define GAME_PANEL_CE_SCORE_5_ELEMENT           110
 201 #define GAME_PANEL_CE_SCORE_6_ELEMENT           111
 202 #define GAME_PANEL_CE_SCORE_7_ELEMENT           112
 203 #define GAME_PANEL_CE_SCORE_8_ELEMENT           113
 204 #define GAME_PANEL_PLAYER_NAME                  114
 205 #define GAME_PANEL_LEVEL_NAME                   115
 206 #define GAME_PANEL_LEVEL_AUTHOR                 116
 207
 208 #define NUM_GAME_PANEL_CONTROLS                 117
 209
 210 struct GamePanelOrderInfo
 211 {
 212   int nr;
 213   int sort_priority;
 214 };
 215
 216 static struct GamePanelOrderInfo game_panel_order[NUM_GAME_PANEL_CONTROLS];
 217
 218 struct GamePanelControlInfo
 219 {
 220   int nr;
 221
 222   struct TextPosInfo *pos;
 223   int type;
 224
 225   int graphic, graphic_active;
 226
 227   int value, last_value;
 228   int frame, last_frame;
 229   int gfx_frame;
 230   int gfx_random;
 231 };
 232
 233 static struct GamePanelControlInfo game_panel_controls[] =
 234 {
 235   {
 236     GAME_PANEL_LEVEL_NUMBER,
 237     &game.panel.level_number,
 238     TYPE_INTEGER,
 239   },
 240   {
 241     GAME_PANEL_GEMS,
 242     &game.panel.gems,
 243     TYPE_INTEGER,
 244   },
 245   {
 246     GAME_PANEL_INVENTORY_COUNT,
 247     &game.panel.inventory_count,
 248     TYPE_INTEGER,
 249   },
 250   {
 251     GAME_PANEL_INVENTORY_FIRST_1,
 252     &game.panel.inventory_first[0],
 253     TYPE_ELEMENT,
 254   },
 255   {
 256     GAME_PANEL_INVENTORY_FIRST_2,
 257     &game.panel.inventory_first[1],
 258     TYPE_ELEMENT,
 259   },
 260   {
 261     GAME_PANEL_INVENTORY_FIRST_3,
 262     &game.panel.inventory_first[2],
 263     TYPE_ELEMENT,
 264   },
 265   {
 266     GAME_PANEL_INVENTORY_FIRST_4,
 267     &game.panel.inventory_first[3],
 268     TYPE_ELEMENT,
 269   },
 270   {
 271     GAME_PANEL_INVENTORY_FIRST_5,
 272     &game.panel.inventory_first[4],
 273     TYPE_ELEMENT,
 274   },
 275   {
 276     GAME_PANEL_INVENTORY_FIRST_6,
 277     &game.panel.inventory_first[5],
 278     TYPE_ELEMENT,
 279   },
 280   {
 281     GAME_PANEL_INVENTORY_FIRST_7,
 282     &game.panel.inventory_first[6],
 283     TYPE_ELEMENT,
 284   },
 285   {
 286     GAME_PANEL_INVENTORY_FIRST_8,
 287     &game.panel.inventory_first[7],
 288     TYPE_ELEMENT,
 289   },
 290   {
 291     GAME_PANEL_INVENTORY_LAST_1,
 292     &game.panel.inventory_last[0],
 293     TYPE_ELEMENT,
 294   },
 295   {
 296     GAME_PANEL_INVENTORY_LAST_2,
 297     &game.panel.inventory_last[1],
 298     TYPE_ELEMENT,
 299   },
 300   {
 301     GAME_PANEL_INVENTORY_LAST_3,
 302     &game.panel.inventory_last[2],
 303     TYPE_ELEMENT,
 304   },
 305   {
 306     GAME_PANEL_INVENTORY_LAST_4,
 307     &game.panel.inventory_last[3],
 308     TYPE_ELEMENT,
 309   },
 310   {
 311     GAME_PANEL_INVENTORY_LAST_5,
 312     &game.panel.inventory_last[4],
 313     TYPE_ELEMENT,
 314   },
 315   {
 316     GAME_PANEL_INVENTORY_LAST_6,
 317     &game.panel.inventory_last[5],
 318     TYPE_ELEMENT,
 319   },
 320   {
 321     GAME_PANEL_INVENTORY_LAST_7,
 322     &game.panel.inventory_last[6],
 323     TYPE_ELEMENT,
 324   },
 325   {
 326     GAME_PANEL_INVENTORY_LAST_8,
 327     &game.panel.inventory_last[7],
 328     TYPE_ELEMENT,
 329   },
 330   {
 331     GAME_PANEL_KEY_1,
 332     &game.panel.key[0],
 333     TYPE_ELEMENT,
 334   },
 335   {
 336     GAME_PANEL_KEY_2,
 337     &game.panel.key[1],
 338     TYPE_ELEMENT,
 339   },
 340   {
 341     GAME_PANEL_KEY_3,
 342     &game.panel.key[2],
 343     TYPE_ELEMENT,
 344   },
 345   {
 346     GAME_PANEL_KEY_4,
 347     &game.panel.key[3],
 348     TYPE_ELEMENT,
 349   },
 350   {
 351     GAME_PANEL_KEY_5,
 352     &game.panel.key[4],
 353     TYPE_ELEMENT,
 354   },
 355   {
 356     GAME_PANEL_KEY_6,
 357     &game.panel.key[5],
 358     TYPE_ELEMENT,
 359   },
 360   {
 361     GAME_PANEL_KEY_7,
 362     &game.panel.key[6],
 363     TYPE_ELEMENT,
 364   },
 365   {
 366     GAME_PANEL_KEY_8,
 367     &game.panel.key[7],
 368     TYPE_ELEMENT,
 369   },
 370   {
 371     GAME_PANEL_KEY_WHITE,
 372     &game.panel.key_white,
 373     TYPE_ELEMENT,
 374   },
 375   {
 376     GAME_PANEL_KEY_WHITE_COUNT,
 377     &game.panel.key_white_count,
 378     TYPE_INTEGER,
 379   },
 380   {
 381     GAME_PANEL_SCORE,
 382     &game.panel.score,
 383     TYPE_INTEGER,
 384   },
 385   {
 386     GAME_PANEL_HIGHSCORE,
 387     &game.panel.highscore,
 388     TYPE_INTEGER,
 389   },
 390   {
 391     GAME_PANEL_TIME,
 392     &game.panel.time,
 393     TYPE_INTEGER,
 394   },
 395   {
 396     GAME_PANEL_TIME_HH,
 397     &game.panel.time_hh,
 398     TYPE_INTEGER,
 399   },
 400   {
 401     GAME_PANEL_TIME_MM,
 402     &game.panel.time_mm,
 403     TYPE_INTEGER,
 404   },
 405   {
 406     GAME_PANEL_TIME_SS,
 407     &game.panel.time_ss,
 408     TYPE_INTEGER,
 409   },
 410   {
 411     GAME_PANEL_TIME_ANIM,
 412     &game.panel.time_anim,
 413     TYPE_GRAPHIC,
 414
 415     IMG_GFX_GAME_PANEL_TIME_ANIM,
 416     IMG_GFX_GAME_PANEL_TIME_ANIM_ACTIVE
 417   },
 418   {
 419     GAME_PANEL_HEALTH,
 420     &game.panel.health,
 421     TYPE_INTEGER,
 422   },
 423   {
 424     GAME_PANEL_HEALTH_ANIM,
 425     &game.panel.health_anim,
 426     TYPE_GRAPHIC,
 427
 428     IMG_GFX_GAME_PANEL_HEALTH_ANIM,
 429     IMG_GFX_GAME_PANEL_HEALTH_ANIM_ACTIVE
 430   },
 431   {
 432     GAME_PANEL_FRAME,
 433     &game.panel.frame,
 434     TYPE_INTEGER,
 435   },
 436   {
 437     GAME_PANEL_SHIELD_NORMAL,
 438     &game.panel.shield_normal,
 439     TYPE_ELEMENT,
 440   },
 441   {
 442     GAME_PANEL_SHIELD_NORMAL_TIME,
 443     &game.panel.shield_normal_time,
 444     TYPE_INTEGER,
 445   },
 446   {
 447     GAME_PANEL_SHIELD_DEADLY,
 448     &game.panel.shield_deadly,
 449     TYPE_ELEMENT,
 450   },
 451   {
 452     GAME_PANEL_SHIELD_DEADLY_TIME,
 453     &game.panel.shield_deadly_time,
 454     TYPE_INTEGER,
 455   },
 456   {
 457     GAME_PANEL_EXIT,
 458     &game.panel.exit,
 459     TYPE_ELEMENT,
 460   },
 461   {
 462     GAME_PANEL_EMC_MAGIC_BALL,
 463     &game.panel.emc_magic_ball,
 464     TYPE_ELEMENT,
 465   },
 466   {
 467     GAME_PANEL_EMC_MAGIC_BALL_SWITCH,
 468     &game.panel.emc_magic_ball_switch,
 469     TYPE_ELEMENT,
 470   },
 471   {
 472     GAME_PANEL_LIGHT_SWITCH,
 473     &game.panel.light_switch,
 474     TYPE_ELEMENT,
 475   },
 476   {
 477     GAME_PANEL_LIGHT_SWITCH_TIME,
 478     &game.panel.light_switch_time,
 479     TYPE_INTEGER,
 480   },
 481   {
 482     GAME_PANEL_TIMEGATE_SWITCH,
 483     &game.panel.timegate_switch,
 484     TYPE_ELEMENT,
 485   },
 486   {
 487     GAME_PANEL_TIMEGATE_SWITCH_TIME,
 488     &game.panel.timegate_switch_time,
 489     TYPE_INTEGER,
 490   },
 491   {
 492     GAME_PANEL_SWITCHGATE_SWITCH,
 493     &game.panel.switchgate_switch,
 494     TYPE_ELEMENT,
 495   },
 496   {
 497     GAME_PANEL_EMC_LENSES,
 498     &game.panel.emc_lenses,
 499     TYPE_ELEMENT,
 500   },
 501   {
 502     GAME_PANEL_EMC_LENSES_TIME,
 503     &game.panel.emc_lenses_time,
 504     TYPE_INTEGER,
 505   },
 506   {
 507     GAME_PANEL_EMC_MAGNIFIER,
 508     &game.panel.emc_magnifier,
 509     TYPE_ELEMENT,
 510   },
 511   {
 512     GAME_PANEL_EMC_MAGNIFIER_TIME,
 513     &game.panel.emc_magnifier_time,
 514     TYPE_INTEGER,
 515   },
 516   {
 517     GAME_PANEL_BALLOON_SWITCH,
 518     &game.panel.balloon_switch,
 519     TYPE_ELEMENT,
 520   },
 521   {
 522     GAME_PANEL_DYNABOMB_NUMBER,
 523     &game.panel.dynabomb_number,
 524     TYPE_INTEGER,
 525   },
 526   {
 527     GAME_PANEL_DYNABOMB_SIZE,
 528     &game.panel.dynabomb_size,
 529     TYPE_INTEGER,
 530   },
 531   {
 532     GAME_PANEL_DYNABOMB_POWER,
 533     &game.panel.dynabomb_power,
 534     TYPE_ELEMENT,
 535   },
 536   {
 537     GAME_PANEL_PENGUINS,
 538     &game.panel.penguins,
 539     TYPE_INTEGER,
 540   },
 541   {
 542     GAME_PANEL_SOKOBAN_OBJECTS,
 543     &game.panel.sokoban_objects,
 544     TYPE_INTEGER,
 545   },
 546   {
 547     GAME_PANEL_SOKOBAN_FIELDS,
 548     &game.panel.sokoban_fields,
 549     TYPE_INTEGER,
 550   },
 551   {
 552     GAME_PANEL_ROBOT_WHEEL,
 553     &game.panel.robot_wheel,
 554     TYPE_ELEMENT,
 555   },
 556   {
 557     GAME_PANEL_CONVEYOR_BELT_1,
 558     &game.panel.conveyor_belt[0],
 559     TYPE_ELEMENT,
 560   },
 561   {
 562     GAME_PANEL_CONVEYOR_BELT_2,
 563     &game.panel.conveyor_belt[1],
 564     TYPE_ELEMENT,
 565   },
 566   {
 567     GAME_PANEL_CONVEYOR_BELT_3,
 568     &game.panel.conveyor_belt[2],
 569     TYPE_ELEMENT,
 570   },
 571   {
 572     GAME_PANEL_CONVEYOR_BELT_4,
 573     &game.panel.conveyor_belt[3],
 574     TYPE_ELEMENT,
 575   },
 576   {
 577     GAME_PANEL_CONVEYOR_BELT_1_SWITCH,
 578     &game.panel.conveyor_belt_switch[0],
 579     TYPE_ELEMENT,
 580   },
 581   {
 582     GAME_PANEL_CONVEYOR_BELT_2_SWITCH,
 583     &game.panel.conveyor_belt_switch[1],
 584     TYPE_ELEMENT,
 585   },
 586   {
 587     GAME_PANEL_CONVEYOR_BELT_3_SWITCH,
 588     &game.panel.conveyor_belt_switch[2],
 589     TYPE_ELEMENT,
 590   },
 591   {
 592     GAME_PANEL_CONVEYOR_BELT_4_SWITCH,
 593     &game.panel.conveyor_belt_switch[3],
 594     TYPE_ELEMENT,
 595   },
 596   {
 597     GAME_PANEL_MAGIC_WALL,
 598     &game.panel.magic_wall,
 599     TYPE_ELEMENT,
 600   },
 601   {
 602     GAME_PANEL_MAGIC_WALL_TIME,
 603     &game.panel.magic_wall_time,
 604     TYPE_INTEGER,
 605   },
 606   {
 607     GAME_PANEL_GRAVITY_STATE,
 608     &game.panel.gravity_state,
 609     TYPE_STRING,
 610   },
 611   {
 612     GAME_PANEL_GRAPHIC_1,
 613     &game.panel.graphic[0],
 614     TYPE_ELEMENT,
 615   },
 616   {
 617     GAME_PANEL_GRAPHIC_2,
 618     &game.panel.graphic[1],
 619     TYPE_ELEMENT,
 620   },
 621   {
 622     GAME_PANEL_GRAPHIC_3,
 623     &game.panel.graphic[2],
 624     TYPE_ELEMENT,
 625   },
 626   {
 627     GAME_PANEL_GRAPHIC_4,
 628     &game.panel.graphic[3],
 629     TYPE_ELEMENT,
 630   },
 631   {
 632     GAME_PANEL_GRAPHIC_5,
 633     &game.panel.graphic[4],
 634     TYPE_ELEMENT,
 635   },
 636   {
 637     GAME_PANEL_GRAPHIC_6,
 638     &game.panel.graphic[5],
 639     TYPE_ELEMENT,
 640   },
 641   {
 642     GAME_PANEL_GRAPHIC_7,
 643     &game.panel.graphic[6],
 644     TYPE_ELEMENT,
 645   },
 646   {
 647     GAME_PANEL_GRAPHIC_8,
 648     &game.panel.graphic[7],
 649     TYPE_ELEMENT,
 650   },
 651   {
 652     GAME_PANEL_ELEMENT_1,
 653     &game.panel.element[0],
 654     TYPE_ELEMENT,
 655   },
 656   {
 657     GAME_PANEL_ELEMENT_2,
 658     &game.panel.element[1],
 659     TYPE_ELEMENT,
 660   },
 661   {
 662     GAME_PANEL_ELEMENT_3,
 663     &game.panel.element[2],
 664     TYPE_ELEMENT,
 665   },
 666   {
 667     GAME_PANEL_ELEMENT_4,
 668     &game.panel.element[3],
 669     TYPE_ELEMENT,
 670   },
 671   {
 672     GAME_PANEL_ELEMENT_5,
 673     &game.panel.element[4],
 674     TYPE_ELEMENT,
 675   },
 676   {
 677     GAME_PANEL_ELEMENT_6,
 678     &game.panel.element[5],
 679     TYPE_ELEMENT,
 680   },
 681   {
 682     GAME_PANEL_ELEMENT_7,
 683     &game.panel.element[6],
 684     TYPE_ELEMENT,
 685   },
 686   {
 687     GAME_PANEL_ELEMENT_8,
 688     &game.panel.element[7],
 689     TYPE_ELEMENT,
 690   },
 691   {
 692     GAME_PANEL_ELEMENT_COUNT_1,
 693     &game.panel.element_count[0],
 694     TYPE_INTEGER,
 695   },
 696   {
 697     GAME_PANEL_ELEMENT_COUNT_2,
 698     &game.panel.element_count[1],
 699     TYPE_INTEGER,
 700   },
 701   {
 702     GAME_PANEL_ELEMENT_COUNT_3,
 703     &game.panel.element_count[2],
 704     TYPE_INTEGER,
 705   },
 706   {
 707     GAME_PANEL_ELEMENT_COUNT_4,
 708     &game.panel.element_count[3],
 709     TYPE_INTEGER,
 710   },
 711   {
 712     GAME_PANEL_ELEMENT_COUNT_5,
 713     &game.panel.element_count[4],
 714     TYPE_INTEGER,
 715   },
 716   {
 717     GAME_PANEL_ELEMENT_COUNT_6,
 718     &game.panel.element_count[5],
 719     TYPE_INTEGER,
 720   },
 721   {
 722     GAME_PANEL_ELEMENT_COUNT_7,
 723     &game.panel.element_count[6],
 724     TYPE_INTEGER,
 725   },
 726   {
 727     GAME_PANEL_ELEMENT_COUNT_8,
 728     &game.panel.element_count[7],
 729     TYPE_INTEGER,
 730   },
 731   {
 732     GAME_PANEL_CE_SCORE_1,
 733     &game.panel.ce_score[0],
 734     TYPE_INTEGER,
 735   },
 736   {
 737     GAME_PANEL_CE_SCORE_2,
 738     &game.panel.ce_score[1],
 739     TYPE_INTEGER,
 740   },
 741   {
 742     GAME_PANEL_CE_SCORE_3,
 743     &game.panel.ce_score[2],
 744     TYPE_INTEGER,
 745   },
 746   {
 747     GAME_PANEL_CE_SCORE_4,
 748     &game.panel.ce_score[3],
 749     TYPE_INTEGER,
 750   },
 751   {
 752     GAME_PANEL_CE_SCORE_5,
 753     &game.panel.ce_score[4],
 754     TYPE_INTEGER,
 755   },
 756   {
 757     GAME_PANEL_CE_SCORE_6,
 758     &game.panel.ce_score[5],
 759     TYPE_INTEGER,
 760   },
 761   {
 762     GAME_PANEL_CE_SCORE_7,
 763     &game.panel.ce_score[6],
 764     TYPE_INTEGER,
 765   },
 766   {
 767     GAME_PANEL_CE_SCORE_8,
 768     &game.panel.ce_score[7],
 769     TYPE_INTEGER,
 770   },
 771   {
 772     GAME_PANEL_CE_SCORE_1_ELEMENT,
 773     &game.panel.ce_score_element[0],
 774     TYPE_ELEMENT,
 775   },
 776   {
 777     GAME_PANEL_CE_SCORE_2_ELEMENT,
 778     &game.panel.ce_score_element[1],
 779     TYPE_ELEMENT,
 780   },
 781   {
 782     GAME_PANEL_CE_SCORE_3_ELEMENT,
 783     &game.panel.ce_score_element[2],
 784     TYPE_ELEMENT,
 785   },
 786   {
 787     GAME_PANEL_CE_SCORE_4_ELEMENT,
 788     &game.panel.ce_score_element[3],
 789     TYPE_ELEMENT,
 790   },
 791   {
 792     GAME_PANEL_CE_SCORE_5_ELEMENT,
 793     &game.panel.ce_score_element[4],
 794     TYPE_ELEMENT,
 795   },
 796   {
 797     GAME_PANEL_CE_SCORE_6_ELEMENT,
 798     &game.panel.ce_score_element[5],
 799     TYPE_ELEMENT,
 800   },
 801   {
 802     GAME_PANEL_CE_SCORE_7_ELEMENT,
 803     &game.panel.ce_score_element[6],
 804     TYPE_ELEMENT,
 805   },
 806   {
 807     GAME_PANEL_CE_SCORE_8_ELEMENT,
 808     &game.panel.ce_score_element[7],
 809     TYPE_ELEMENT,
 810   },
 811   {
 812     GAME_PANEL_PLAYER_NAME,
 813     &game.panel.player_name,
 814     TYPE_STRING,
 815   },
 816   {
 817     GAME_PANEL_LEVEL_NAME,
 818     &game.panel.level_name,
 819     TYPE_STRING,
 820   },
 821   {
 822     GAME_PANEL_LEVEL_AUTHOR,
 823     &game.panel.level_author,
 824     TYPE_STRING,
 825   },
 826
 827   {
 828     -1,
 829     NULL,
 830     -1,
 831   }
 832 };
 833
 834 // values for delayed check of falling and moving elements and for collision
 835 #define CHECK_DELAY_MOVING      3
 836 #define CHECK_DELAY_FALLING     CHECK_DELAY_MOVING
 837 #define CHECK_DELAY_COLLISION   2
 838 #define CHECK_DELAY_IMPACT      CHECK_DELAY_COLLISION
 839
 840 // values for initial player move delay (initial delay counter value)
 841 #define INITIAL_MOVE_DELAY_OFF  -1
 842 #define INITIAL_MOVE_DELAY_ON   0
 843
 844 // values for player movement speed (which is in fact a delay value)
 845 #define MOVE_DELAY_MIN_SPEED    32
 846 #define MOVE_DELAY_NORMAL_SPEED 8
 847 #define MOVE_DELAY_HIGH_SPEED   4
 848 #define MOVE_DELAY_MAX_SPEED    1
 849
 850 #define DOUBLE_MOVE_DELAY(x)    (x = (x < MOVE_DELAY_MIN_SPEED ? x * 2 : x))
 851 #define HALVE_MOVE_DELAY(x)     (x = (x > MOVE_DELAY_MAX_SPEED ? x / 2 : x))
 852
 853 #define DOUBLE_PLAYER_SPEED(p)  (HALVE_MOVE_DELAY( (p)->move_delay_value))
 854 #define HALVE_PLAYER_SPEED(p)   (DOUBLE_MOVE_DELAY((p)->move_delay_value))
 855
 856 // values for scroll positions
 857 #define SCROLL_POSITION_X(x)    ((x) < SBX_Left  + MIDPOSX ? SBX_Left : \
 858                                  (x) > SBX_Right + MIDPOSX ? SBX_Right :\
 859                                  (x) - MIDPOSX)
 860 #define SCROLL_POSITION_Y(y)    ((y) < SBY_Upper + MIDPOSY ? SBY_Upper :\
 861                                  (y) > SBY_Lower + MIDPOSY ? SBY_Lower :\
 862                                  (y) - MIDPOSY)
 863
 864 // values for other actions
 865 #define MOVE_STEPSIZE_NORMAL    (TILEX / MOVE_DELAY_NORMAL_SPEED)
 866 #define MOVE_STEPSIZE_MIN       (1)
 867 #define MOVE_STEPSIZE_MAX       (TILEX)
 868
 869 #define GET_DX_FROM_DIR(d)      ((d) == MV_LEFT ? -1 : (d) == MV_RIGHT ? 1 : 0)
 870 #define GET_DY_FROM_DIR(d)      ((d) == MV_UP   ? -1 : (d) == MV_DOWN  ? 1 : 0)
 871
 872 #define INIT_GFX_RANDOM()       (GetSimpleRandom(1000000))
 873
 874 #define GET_NEW_PUSH_DELAY(e)   (   (element_info[e].push_delay_fixed) + \
 875                                  RND(element_info[e].push_delay_random))
 876 #define GET_NEW_DROP_DELAY(e)   (   (element_info[e].drop_delay_fixed) + \
 877                                  RND(element_info[e].drop_delay_random))
 878 #define GET_NEW_MOVE_DELAY(e)   (   (element_info[e].move_delay_fixed) + \
 879                                  RND(element_info[e].move_delay_random))
 880 #define GET_MAX_MOVE_DELAY(e)   (   (element_info[e].move_delay_fixed) + \
 881                                     (element_info[e].move_delay_random))
 882 #define GET_NEW_STEP_DELAY(e)   (   (element_info[e].step_delay_fixed) + \
 883                                  RND(element_info[e].step_delay_random))
 884 #define GET_MAX_STEP_DELAY(e)   (   (element_info[e].step_delay_fixed) + \
 885                                     (element_info[e].step_delay_random))
 886 #define GET_NEW_CE_VALUE(e)     (   (element_info[e].ce_value_fixed_initial) +\
 887                                  RND(element_info[e].ce_value_random_initial))
 888 #define GET_CE_SCORE(e)         (   (element_info[e].collect_score))
 889 #define GET_CHANGE_DELAY(c)     (   ((c)->delay_fixed  * (c)->delay_frames) + \
 890                                  RND((c)->delay_random * (c)->delay_frames))
 891 #define GET_CE_DELAY_VALUE(c)   (   ((c)->delay_fixed) + \
 892                                  RND((c)->delay_random))
 893
 894
 895 #define GET_VALID_RUNTIME_ELEMENT(e)                                    \
 896          ((e) >= NUM_RUNTIME_ELEMENTS ? EL_UNKNOWN : (e))
 897
 898 #define RESOLVED_REFERENCE_ELEMENT(be, e)                               \
 899         ((be) + (e) - EL_SELF < EL_CUSTOM_START ? EL_CUSTOM_START :     \
 900          (be) + (e) - EL_SELF > EL_CUSTOM_END   ? EL_CUSTOM_END :       \
 901          (be) + (e) - EL_SELF)
 902
 903 #define GET_PLAYER_FROM_BITS(p)                                         \
 904         (EL_PLAYER_1 + ((p) != PLAYER_BITS_ANY ? log_2(p) : 0))
 905
 906 #define GET_TARGET_ELEMENT(be, e, ch, cv, cs)                           \
 907         ((e) == EL_TRIGGER_PLAYER   ? (ch)->actual_trigger_player    :  \
 908          (e) == EL_TRIGGER_ELEMENT  ? (ch)->actual_trigger_element   :  \
 909          (e) == EL_TRIGGER_CE_VALUE ? (ch)->actual_trigger_ce_value  :  \
 910          (e) == EL_TRIGGER_CE_SCORE ? (ch)->actual_trigger_ce_score  :  \
 911          (e) == EL_CURRENT_CE_VALUE ? (cv) :                            \
 912          (e) == EL_CURRENT_CE_SCORE ? (cs) :                            \
 913          (e) >= EL_PREV_CE_8 && (e) <= EL_NEXT_CE_8 ?                   \
 914          RESOLVED_REFERENCE_ELEMENT(be, e) :                            \
 915          (e))
 916
 917 #define CAN_GROW_INTO(e)                                                \
 918         ((e) == EL_SAND || (IS_DIGGABLE(e) && level.grow_into_diggable))
 919
 920 #define ELEMENT_CAN_ENTER_FIELD_BASE_X(x, y, condition)                 \
 921                 (IN_LEV_FIELD(x, y) && (IS_FREE(x, y) ||                \
 922                                         (condition)))
 923
 924 #define ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, condition)              \
 925                 (IN_LEV_FIELD(x, y) && (IS_FREE(x, y) ||                \
 926                                         (CAN_MOVE_INTO_ACID(e) &&       \
 927                                          Tile[x][y] == EL_ACID) ||      \
 928                                         (condition)))
 929
 930 #define ELEMENT_CAN_ENTER_FIELD_BASE_3(e, x, y, condition)              \
 931                 (IN_LEV_FIELD(x, y) && (IS_FREE_OR_PLAYER(x, y) ||      \
 932                                         (CAN_MOVE_INTO_ACID(e) &&       \
 933                                          Tile[x][y] == EL_ACID) ||      \
 934                                         (condition)))
 935
 936 #define ELEMENT_CAN_ENTER_FIELD_BASE_4(e, x, y, condition)              \
 937                 (IN_LEV_FIELD(x, y) && (IS_FREE(x, y) ||                \
 938                                         (condition) ||                  \
 939                                         (CAN_MOVE_INTO_ACID(e) &&       \
 940                                          Tile[x][y] == EL_ACID) ||      \
 941                                         (DONT_COLLIDE_WITH(e) &&        \
 942                                          IS_PLAYER(x, y) &&             \
 943                                          !PLAYER_ENEMY_PROTECTED(x, y))))
 944
 945 #define ELEMENT_CAN_ENTER_FIELD(e, x, y)                                \
 946         ELEMENT_CAN_ENTER_FIELD_BASE_4(e, x, y, 0)
 947
 948 #define SATELLITE_CAN_ENTER_FIELD(x, y)                                 \
 949         ELEMENT_CAN_ENTER_FIELD_BASE_2(EL_SATELLITE, x, y, 0)
 950
 951 #define ANDROID_CAN_ENTER_FIELD(e, x, y)                                \
 952         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, Tile[x][y] == EL_EMC_PLANT)
 953
 954 #define ANDROID_CAN_CLONE_FIELD(x, y)                                   \
 955         (IN_LEV_FIELD(x, y) && (CAN_BE_CLONED_BY_ANDROID(Tile[x][y]) || \
 956                                 CAN_BE_CLONED_BY_ANDROID(EL_TRIGGER_ELEMENT)))
 957
 958 #define ENEMY_CAN_ENTER_FIELD(e, x, y)                                  \
 959         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, 0)
 960
 961 #define YAMYAM_CAN_ENTER_FIELD(e, x, y)                                 \
 962         ELEMENT_CAN_ENTER_FIELD_BASE_3(e, x, y, Tile[x][y] == EL_DIAMOND)
 963
 964 #define DARK_YAMYAM_CAN_ENTER_FIELD(e, x, y)                            \
 965         ELEMENT_CAN_ENTER_FIELD_BASE_3(e, x, y, IS_FOOD_DARK_YAMYAM(Tile[x][y]))
 966
 967 #define PACMAN_CAN_ENTER_FIELD(e, x, y)                                 \
 968         ELEMENT_CAN_ENTER_FIELD_BASE_3(e, x, y, IS_AMOEBOID(Tile[x][y]))
 969
 970 #define PIG_CAN_ENTER_FIELD(e, x, y)                                    \
 971         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, IS_FOOD_PIG(Tile[x][y]))
 972
 973 #define PENGUIN_CAN_ENTER_FIELD(e, x, y)                                \
 974         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, (Tile[x][y] == EL_EXIT_OPEN || \
 975                                                  Tile[x][y] == EL_EM_EXIT_OPEN || \
 976                                                  Tile[x][y] == EL_STEEL_EXIT_OPEN || \
 977                                                  Tile[x][y] == EL_EM_STEEL_EXIT_OPEN || \
 978                                                  IS_FOOD_PENGUIN(Tile[x][y])))
 979 #define DRAGON_CAN_ENTER_FIELD(e, x, y)                                 \
 980         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, 0)
 981
 982 #define MOLE_CAN_ENTER_FIELD(e, x, y, condition)                        \
 983         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, (condition))
 984
 985 #define SPRING_CAN_ENTER_FIELD(e, x, y)                                 \
 986         ELEMENT_CAN_ENTER_FIELD_BASE_2(e, x, y, 0)
 987
 988 #define SPRING_CAN_BUMP_FROM_FIELD(x, y)                                \
 989         (IN_LEV_FIELD(x, y) && (Tile[x][y] == EL_EMC_SPRING_BUMPER ||   \
 990                                 Tile[x][y] == EL_EMC_SPRING_BUMPER_ACTIVE))
 991
 992 #define MOVE_ENTER_EL(e)        (element_info[e].move_enter_element)
 993
 994 #define CE_ENTER_FIELD_COND(e, x, y)                                    \
 995                 (!IS_PLAYER(x, y) &&                                    \
 996                  IS_EQUAL_OR_IN_GROUP(Tile[x][y], MOVE_ENTER_EL(e)))
 997
 998 #define CUSTOM_ELEMENT_CAN_ENTER_FIELD(e, x, y)                         \
 999         ELEMENT_CAN_ENTER_FIELD_BASE_4(e, x, y, CE_ENTER_FIELD_COND(e, x, y))
1000
1001 #define IN_LEV_FIELD_AND_IS_FREE(x, y)  (IN_LEV_FIELD(x, y) &&  IS_FREE(x, y))
1002 #define IN_LEV_FIELD_AND_NOT_FREE(x, y) (IN_LEV_FIELD(x, y) && !IS_FREE(x, y))
1003
1004 #define ACCESS_FROM(e, d)               (element_info[e].access_direction &(d))
1005 #define IS_WALKABLE_FROM(e, d)          (IS_WALKABLE(e)   && ACCESS_FROM(e, d))
1006 #define IS_PASSABLE_FROM(e, d)          (IS_PASSABLE(e)   && ACCESS_FROM(e, d))
1007 #define IS_ACCESSIBLE_FROM(e, d)        (IS_ACCESSIBLE(e) && ACCESS_FROM(e, d))
1008
1009 #define MM_HEALTH(x)            (MIN(MAX(0, MAX_HEALTH - (x)), MAX_HEALTH))
1010
1011 // game button identifiers
1012 #define GAME_CTRL_ID_STOP               0
1013 #define GAME_CTRL_ID_PAUSE              1
1014 #define GAME_CTRL_ID_PLAY               2
1015 #define GAME_CTRL_ID_UNDO               3
1016 #define GAME_CTRL_ID_REDO               4
1017 #define GAME_CTRL_ID_SAVE               5
1018 #define GAME_CTRL_ID_PAUSE2             6
1019 #define GAME_CTRL_ID_LOAD               7
1020 #define GAME_CTRL_ID_PANEL_STOP         8
1021 #define GAME_CTRL_ID_PANEL_PAUSE        9
1022 #define GAME_CTRL_ID_PANEL_PLAY         10
1023 #define GAME_CTRL_ID_TOUCH_STOP         11
1024 #define GAME_CTRL_ID_TOUCH_PAUSE        12
1025 #define SOUND_CTRL_ID_MUSIC             13
1026 #define SOUND_CTRL_ID_LOOPS             14
1027 #define SOUND_CTRL_ID_SIMPLE            15
1028 #define SOUND_CTRL_ID_PANEL_MUSIC       16
1029 #define SOUND_CTRL_ID_PANEL_LOOPS       17
1030 #define SOUND_CTRL_ID_PANEL_SIMPLE      18
1031
1032 #define NUM_GAME_BUTTONS                19
1033
1034
1035 // forward declaration for internal use
1036
1037 static void CreateField(int, int, int);
1038
1039 static void ResetGfxAnimation(int, int);
1040
1041 static void SetPlayerWaiting(struct PlayerInfo *, boolean);
1042 static void AdvanceFrameAndPlayerCounters(int);
1043
1044 static boolean MovePlayerOneStep(struct PlayerInfo *, int, int, int, int);
1045 static boolean MovePlayer(struct PlayerInfo *, int, int);
1046 static void ScrollPlayer(struct PlayerInfo *, int);
1047 static void ScrollScreen(struct PlayerInfo *, int);
1048
1049 static int DigField(struct PlayerInfo *, int, int, int, int, int, int, int);
1050 static boolean DigFieldByCE(int, int, int);
1051 static boolean SnapField(struct PlayerInfo *, int, int);
1052 static boolean DropElement(struct PlayerInfo *);
1053
1054 static void InitBeltMovement(void);
1055 static void CloseAllOpenTimegates(void);
1056 static void CheckGravityMovement(struct PlayerInfo *);
1057 static void CheckGravityMovementWhenNotMoving(struct PlayerInfo *);
1058 static void KillPlayerUnlessEnemyProtected(int, int);
1059 static void KillPlayerUnlessExplosionProtected(int, int);
1060
1061 static void CheckNextToConditions(int, int);
1062 static void TestIfPlayerNextToCustomElement(int, int);
1063 static void TestIfPlayerTouchesCustomElement(int, int);
1064 static void TestIfElementNextToCustomElement(int, int);
1065 static void TestIfElementTouchesCustomElement(int, int);
1066 static void TestIfElementHitsCustomElement(int, int, int);
1067
1068 static void HandleElementChange(int, int, int);
1069 static void ExecuteCustomElementAction(int, int, int, int);
1070 static boolean ChangeElement(int, int, int, int);
1071
1072 static boolean CheckTriggeredElementChangeExt(int, int, int, int, int, int, int);
1073 #define CheckTriggeredElementChange(x, y, e, ev)                        \
1074         CheckTriggeredElementChangeExt(x,y,e,ev, CH_PLAYER_ANY, CH_SIDE_ANY, -1)
1075 #define CheckTriggeredElementChangeByPlayer(x, y, e, ev, p, s)          \
1076         CheckTriggeredElementChangeExt(x, y, e, ev, p, s, -1)
1077 #define CheckTriggeredElementChangeBySide(x, y, e, ev, s)               \
1078         CheckTriggeredElementChangeExt(x, y, e, ev, CH_PLAYER_ANY, s, -1)
1079 #define CheckTriggeredElementChangeByPage(x, y, e, ev, p)               \
1080         CheckTriggeredElementChangeExt(x,y,e,ev, CH_PLAYER_ANY, CH_SIDE_ANY, p)
1081 #define CheckTriggeredElementChangeByMouse(x, y, e, ev, s)              \
1082         CheckTriggeredElementChangeExt(x, y, e, ev, CH_PLAYER_ANY, s, -1)
1083
1084 static boolean CheckElementChangeExt(int, int, int, int, int, int, int);
1085 #define CheckElementChange(x, y, e, te, ev)                             \
1086         CheckElementChangeExt(x, y, e, te, ev, CH_PLAYER_ANY, CH_SIDE_ANY)
1087 #define CheckElementChangeByPlayer(x, y, e, ev, p, s)                   \
1088         CheckElementChangeExt(x, y, e, EL_EMPTY, ev, p, s)
1089 #define CheckElementChangeBySide(x, y, e, te, ev, s)                    \
1090         CheckElementChangeExt(x, y, e, te, ev, CH_PLAYER_ANY, s)
1091 #define CheckElementChangeByMouse(x, y, e, ev, s)                       \
1092         CheckElementChangeExt(x, y, e, EL_UNDEFINED, ev, CH_PLAYER_ANY, s)
1093
1094 static void PlayLevelSound(int, int, int);
1095 static void PlayLevelSoundNearest(int, int, int);
1096 static void PlayLevelSoundAction(int, int, int);
1097 static void PlayLevelSoundElementAction(int, int, int, int);
1098 static void PlayLevelSoundElementActionIfLoop(int, int, int, int);
1099 static void PlayLevelSoundActionIfLoop(int, int, int);
1100 static void StopLevelSoundActionIfLoop(int, int, int);
1101 static void PlayLevelMusic(void);
1102 static void FadeLevelSoundsAndMusic(void);
1103
1104 static void HandleGameButtons(struct GadgetInfo *);
1105
1106 int AmoebaNeighbourNr(int, int);
1107 void AmoebaToDiamond(int, int);
1108 void ContinueMoving(int, int);
1109 void Bang(int, int);
1110 void InitMovDir(int, int);
1111 void InitAmoebaNr(int, int);
1112 void NewHighScore(int, boolean);
1113
1114 void TestIfGoodThingHitsBadThing(int, int, int);
1115 void TestIfBadThingHitsGoodThing(int, int, int);
1116 void TestIfPlayerTouchesBadThing(int, int);
1117 void TestIfPlayerRunsIntoBadThing(int, int, int);
1118 void TestIfBadThingTouchesPlayer(int, int);
1119 void TestIfBadThingRunsIntoPlayer(int, int, int);
1120 void TestIfFriendTouchesBadThing(int, int);
1121 void TestIfBadThingTouchesFriend(int, int);
1122 void TestIfBadThingTouchesOtherBadThing(int, int);
1123 void TestIfGoodThingGetsHitByBadThing(int, int, int);
1124
1125 void KillPlayer(struct PlayerInfo *);
1126 void BuryPlayer(struct PlayerInfo *);
1127 void RemovePlayer(struct PlayerInfo *);
1128 void ExitPlayer(struct PlayerInfo *);
1129
1130 static int getInvisibleActiveFromInvisibleElement(int);
1131 static int getInvisibleFromInvisibleActiveElement(int);
1132
1133 static void TestFieldAfterSnapping(int, int, int, int, int);
1134
1135 static struct GadgetInfo *game_gadget[NUM_GAME_BUTTONS];
1136
1137 // for detection of endless loops, caused by custom element programming
1138 // (using maximal playfield width x 10 is just a rough approximation)
1139 #define MAX_ELEMENT_CHANGE_RECURSION_DEPTH      (MAX_PLAYFIELD_WIDTH * 10)
1140
1141 #define RECURSION_LOOP_DETECTION_START(e, rc)                           \
1142 {                                                                       \
1143   if (recursion_loop_detected)                                          \
1144     return (rc);                                                        \
1145                                                                         \
1146   if (recursion_loop_depth > MAX_ELEMENT_CHANGE_RECURSION_DEPTH)        \
1147   {                                                                     \
1148     recursion_loop_detected = TRUE;                                     \
1149     recursion_loop_element = (e);                                       \
1150   }                                                                     \
1151                                                                         \
1152   recursion_loop_depth++;                                               \
1153 }
1154
1155 #define RECURSION_LOOP_DETECTION_END()                                  \
1156 {                                                                       \
1157   recursion_loop_depth--;                                               \
1158 }
1159
1160 static int recursion_loop_depth;
1161 static boolean recursion_loop_detected;
1162 static boolean recursion_loop_element;
1163
1164 static int map_player_action[MAX_PLAYERS];
1165
1166
1167 // ----------------------------------------------------------------------------
1168 // definition of elements that automatically change to other elements after
1169 // a specified time, eventually calling a function when changing
1170 // ----------------------------------------------------------------------------
1171
1172 // forward declaration for changer functions
1173 static void InitBuggyBase(int, int);
1174 static void WarnBuggyBase(int, int);
1175
1176 static void InitTrap(int, int);
1177 static void ActivateTrap(int, int);
1178 static void ChangeActiveTrap(int, int);
1179
1180 static void InitRobotWheel(int, int);
1181 static void RunRobotWheel(int, int);
1182 static void StopRobotWheel(int, int);
1183
1184 static void InitTimegateWheel(int, int);
1185 static void RunTimegateWheel(int, int);
1186
1187 static void InitMagicBallDelay(int, int);
1188 static void ActivateMagicBall(int, int);
1189
1190 struct ChangingElementInfo
1191 {
1192   int element;
1193   int target_element;
1194   int change_delay;
1195   void (*pre_change_function)(int x, int y);
1196   void (*change_function)(int x, int y);
1197   void (*post_change_function)(int x, int y);
1198 };
1199
1200 static struct ChangingElementInfo change_delay_list[] =
1201 {
1202   {
1203     EL_NUT_BREAKING,
1204     EL_EMERALD,
1205     6,
1206     NULL,
1207     NULL,
1208     NULL
1209   },
1210   {
1211     EL_PEARL_BREAKING,
1212     EL_EMPTY,
1213     8,
1214     NULL,
1215     NULL,
1216     NULL
1217   },
1218   {
1219     EL_EXIT_OPENING,
1220     EL_EXIT_OPEN,
1221     29,
1222     NULL,
1223     NULL,
1224     NULL
1225   },
1226   {
1227     EL_EXIT_CLOSING,
1228     EL_EXIT_CLOSED,
1229     29,
1230     NULL,
1231     NULL,
1232     NULL
1233   },
1234   {
1235     EL_STEEL_EXIT_OPENING,
1236     EL_STEEL_EXIT_OPEN,
1237     29,
1238     NULL,
1239     NULL,
1240     NULL
1241   },
1242   {
1243     EL_STEEL_EXIT_CLOSING,
1244     EL_STEEL_EXIT_CLOSED,
1245     29,
1246     NULL,
1247     NULL,
1248     NULL
1249   },
1250   {
1251     EL_EM_EXIT_OPENING,
1252     EL_EM_EXIT_OPEN,
1253     29,
1254     NULL,
1255     NULL,
1256     NULL
1257   },
1258   {
1259     EL_EM_EXIT_CLOSING,
1260     EL_EMPTY,
1261     29,
1262     NULL,
1263     NULL,
1264     NULL
1265   },
1266   {
1267     EL_EM_STEEL_EXIT_OPENING,
1268     EL_EM_STEEL_EXIT_OPEN,
1269     29,
1270     NULL,
1271     NULL,
1272     NULL
1273   },
1274   {
1275     EL_EM_STEEL_EXIT_CLOSING,
1276     EL_STEELWALL,
1277     29,
1278     NULL,
1279     NULL,
1280     NULL
1281   },
1282   {
1283     EL_SP_EXIT_OPENING,
1284     EL_SP_EXIT_OPEN,
1285     29,
1286     NULL,
1287     NULL,
1288     NULL
1289   },
1290   {
1291     EL_SP_EXIT_CLOSING,
1292     EL_SP_EXIT_CLOSED,
1293     29,
1294     NULL,
1295     NULL,
1296     NULL
1297   },
1298   {
1299     EL_SWITCHGATE_OPENING,
1300     EL_SWITCHGATE_OPEN,
1301     29,
1302     NULL,
1303     NULL,
1304     NULL
1305   },
1306   {
1307     EL_SWITCHGATE_CLOSING,
1308     EL_SWITCHGATE_CLOSED,
1309     29,
1310     NULL,
1311     NULL,
1312     NULL
1313   },
1314   {
1315     EL_TIMEGATE_OPENING,
1316     EL_TIMEGATE_OPEN,
1317     29,
1318     NULL,
1319     NULL,
1320     NULL
1321   },
1322   {
1323     EL_TIMEGATE_CLOSING,
1324     EL_TIMEGATE_CLOSED,
1325     29,
1326     NULL,
1327     NULL,
1328     NULL
1329   },
1330
1331   {
1332     EL_ACID_SPLASH_LEFT,
1333     EL_EMPTY,
1334     8,
1335     NULL,
1336     NULL,
1337     NULL
1338   },
1339   {
1340     EL_ACID_SPLASH_RIGHT,
1341     EL_EMPTY,
1342     8,
1343     NULL,
1344     NULL,
1345     NULL
1346   },
1347   {
1348     EL_SP_BUGGY_BASE,
1349     EL_SP_BUGGY_BASE_ACTIVATING,
1350     0,
1351     InitBuggyBase,
1352     NULL,
1353     NULL
1354   },
1355   {
1356     EL_SP_BUGGY_BASE_ACTIVATING,
1357     EL_SP_BUGGY_BASE_ACTIVE,
1358     0,
1359     InitBuggyBase,
1360     NULL,
1361     NULL
1362   },
1363   {
1364     EL_SP_BUGGY_BASE_ACTIVE,
1365     EL_SP_BUGGY_BASE,
1366     0,
1367     InitBuggyBase,
1368     WarnBuggyBase,
1369     NULL
1370   },
1371   {
1372     EL_TRAP,
1373     EL_TRAP_ACTIVE,
1374     0,
1375     InitTrap,
1376     NULL,
1377     ActivateTrap
1378   },
1379   {
1380     EL_TRAP_ACTIVE,
1381     EL_TRAP,
1382     31,
1383     NULL,
1384     ChangeActiveTrap,
1385     NULL
1386   },
1387   {
1388     EL_ROBOT_WHEEL_ACTIVE,
1389     EL_ROBOT_WHEEL,
1390     0,
1391     InitRobotWheel,
1392     RunRobotWheel,
1393     StopRobotWheel
1394   },
1395   {
1396     EL_TIMEGATE_SWITCH_ACTIVE,
1397     EL_TIMEGATE_SWITCH,
1398     0,
1399     InitTimegateWheel,
1400     RunTimegateWheel,
1401     NULL
1402   },
1403   {
1404     EL_DC_TIMEGATE_SWITCH_ACTIVE,
1405     EL_DC_TIMEGATE_SWITCH,
1406     0,
1407     InitTimegateWheel,
1408     RunTimegateWheel,
1409     NULL
1410   },
1411   {
1412     EL_EMC_MAGIC_BALL_ACTIVE,
1413     EL_EMC_MAGIC_BALL_ACTIVE,
1414     0,
1415     InitMagicBallDelay,
1416     NULL,
1417     ActivateMagicBall
1418   },
1419   {
1420     EL_EMC_SPRING_BUMPER_ACTIVE,
1421     EL_EMC_SPRING_BUMPER,
1422     8,
1423     NULL,
1424     NULL,
1425     NULL
1426   },
1427   {
1428     EL_DIAGONAL_SHRINKING,
1429     EL_UNDEFINED,
1430     0,
1431     NULL,
1432     NULL,
1433     NULL
1434   },
1435   {
1436     EL_DIAGONAL_GROWING,
1437     EL_UNDEFINED,
1438     0,
1439     NULL,
1440     NULL,
1441     NULL,
1442   },
1443
1444   {
1445     EL_UNDEFINED,
1446     EL_UNDEFINED,
1447     -1,
1448     NULL,
1449     NULL,
1450     NULL
1451   }
1452 };
1453
1454 struct
1455 {
1456   int element;
1457   int push_delay_fixed, push_delay_random;
1458 }
1459 push_delay_list[] =
1460 {
1461   { EL_SPRING,                  0, 0 },
1462   { EL_BALLOON,                 0, 0 },
1463
1464   { EL_SOKOBAN_OBJECT,          2, 0 },
1465   { EL_SOKOBAN_FIELD_FULL,      2, 0 },
1466   { EL_SATELLITE,               2, 0 },
1467   { EL_SP_DISK_YELLOW,          2, 0 },
1468
1469   { EL_UNDEFINED,               0, 0 },
1470 };
1471
1472 struct
1473 {
1474   int element;
1475   int move_stepsize;
1476 }
1477 move_stepsize_list[] =
1478 {
1479   { EL_AMOEBA_DROP,             2 },
1480   { EL_AMOEBA_DROPPING,         2 },
1481   { EL_QUICKSAND_FILLING,       1 },
1482   { EL_QUICKSAND_EMPTYING,      1 },
1483   { EL_QUICKSAND_FAST_FILLING,  2 },
1484   { EL_QUICKSAND_FAST_EMPTYING, 2 },
1485   { EL_MAGIC_WALL_FILLING,      2 },
1486   { EL_MAGIC_WALL_EMPTYING,     2 },
1487   { EL_BD_MAGIC_WALL_FILLING,   2 },
1488   { EL_BD_MAGIC_WALL_EMPTYING,  2 },
1489   { EL_DC_MAGIC_WALL_FILLING,   2 },
1490   { EL_DC_MAGIC_WALL_EMPTYING,  2 },
1491
1492   { EL_UNDEFINED,               0 },
1493 };
1494
1495 struct
1496 {
1497   int element;
1498   int count;
1499 }
1500 collect_count_list[] =
1501 {
1502   { EL_EMERALD,                 1 },
1503   { EL_BD_DIAMOND,              1 },
1504   { EL_EMERALD_YELLOW,          1 },
1505   { EL_EMERALD_RED,             1 },
1506   { EL_EMERALD_PURPLE,          1 },
1507   { EL_DIAMOND,                 3 },
1508   { EL_SP_INFOTRON,             1 },
1509   { EL_PEARL,                   5 },
1510   { EL_CRYSTAL,                 8 },
1511
1512   { EL_UNDEFINED,               0 },
1513 };
1514
1515 struct
1516 {
1517   int element;
1518   int direction;
1519 }
1520 access_direction_list[] =
1521 {
1522   { EL_TUBE_ANY,                        MV_LEFT | MV_RIGHT | MV_UP | MV_DOWN },
1523   { EL_TUBE_VERTICAL,                                        MV_UP | MV_DOWN },
1524   { EL_TUBE_HORIZONTAL,                 MV_LEFT | MV_RIGHT                   },
1525   { EL_TUBE_VERTICAL_LEFT,              MV_LEFT |            MV_UP | MV_DOWN },
1526   { EL_TUBE_VERTICAL_RIGHT,                       MV_RIGHT | MV_UP | MV_DOWN },
1527   { EL_TUBE_HORIZONTAL_UP,              MV_LEFT | MV_RIGHT | MV_UP           },
1528   { EL_TUBE_HORIZONTAL_DOWN,            MV_LEFT | MV_RIGHT |         MV_DOWN },
1529   { EL_TUBE_LEFT_UP,                    MV_LEFT |            MV_UP           },
1530   { EL_TUBE_LEFT_DOWN,                  MV_LEFT |                    MV_DOWN },
1531   { EL_TUBE_RIGHT_UP,                             MV_RIGHT | MV_UP           },
1532   { EL_TUBE_RIGHT_DOWN,                           MV_RIGHT |         MV_DOWN },
1533
1534   { EL_SP_PORT_LEFT,                              MV_RIGHT                   },
1535   { EL_SP_PORT_RIGHT,                   MV_LEFT                              },
1536   { EL_SP_PORT_UP,                                                   MV_DOWN },
1537   { EL_SP_PORT_DOWN,                                         MV_UP           },
1538   { EL_SP_PORT_HORIZONTAL,              MV_LEFT | MV_RIGHT                   },
1539   { EL_SP_PORT_VERTICAL,                                     MV_UP | MV_DOWN },
1540   { EL_SP_PORT_ANY,                     MV_LEFT | MV_RIGHT | MV_UP | MV_DOWN },
1541   { EL_SP_GRAVITY_PORT_LEFT,                      MV_RIGHT                   },
1542   { EL_SP_GRAVITY_PORT_RIGHT,           MV_LEFT                              },
1543   { EL_SP_GRAVITY_PORT_UP,                                           MV_DOWN },
1544   { EL_SP_GRAVITY_PORT_DOWN,                                 MV_UP           },
1545   { EL_SP_GRAVITY_ON_PORT_LEFT,                   MV_RIGHT                   },
1546   { EL_SP_GRAVITY_ON_PORT_RIGHT,        MV_LEFT                              },
1547   { EL_SP_GRAVITY_ON_PORT_UP,                                        MV_DOWN },
1548   { EL_SP_GRAVITY_ON_PORT_DOWN,                              MV_UP           },
1549   { EL_SP_GRAVITY_OFF_PORT_LEFT,                  MV_RIGHT                   },
1550   { EL_SP_GRAVITY_OFF_PORT_RIGHT,       MV_LEFT                              },
1551   { EL_SP_GRAVITY_OFF_PORT_UP,                                       MV_DOWN },
1552   { EL_SP_GRAVITY_OFF_PORT_DOWN,                             MV_UP           },
1553
1554   { EL_UNDEFINED,                       MV_NONE                              }
1555 };
1556
1557 static struct XY xy_topdown[] =
1558 {
1559   {  0, -1 },
1560   { -1,  0 },
1561   { +1,  0 },
1562   {  0, +1 }
1563 };
1564
1565 static boolean trigger_events[MAX_NUM_ELEMENTS][NUM_CHANGE_EVENTS];
1566
1567 #define IS_AUTO_CHANGING(e)     (element_info[e].has_change_event[CE_DELAY])
1568 #define IS_JUST_CHANGING(x, y)  (ChangeDelay[x][y] != 0)
1569 #define IS_CHANGING(x, y)       (IS_AUTO_CHANGING(Tile[x][y]) || \
1570                                  IS_JUST_CHANGING(x, y))
1571
1572 #define CE_PAGE(e, ce)          (element_info[e].event_page[ce])
1573
1574 // static variables for playfield scan mode (scanning forward or backward)
1575 static int playfield_scan_start_x = 0;
1576 static int playfield_scan_start_y = 0;
1577 static int playfield_scan_delta_x = 1;
1578 static int playfield_scan_delta_y = 1;
1579
1580 #define SCAN_PLAYFIELD(x, y)    for ((y) = playfield_scan_start_y;      \
1581                                      (y) >= 0 && (y) <= lev_fieldy - 1; \
1582                                      (y) += playfield_scan_delta_y)     \
1583                                 for ((x) = playfield_scan_start_x;      \
1584                                      (x) >= 0 && (x) <= lev_fieldx - 1; \
1585                                      (x) += playfield_scan_delta_x)
1586
1587 #ifdef DEBUG
1588 void DEBUG_SetMaximumDynamite(void)
1589 {
1590   int i;
1591
1592   for (i = 0; i < MAX_INVENTORY_SIZE; i++)
1593     if (local_player->inventory_size < MAX_INVENTORY_SIZE)
1594       local_player->inventory_element[local_player->inventory_size++] =
1595         EL_DYNAMITE;
1596 }
1597 #endif
1598
1599 static void InitPlayfieldScanModeVars(void)
1600 {
1601   if (game.use_reverse_scan_direction)
1602   {
1603     playfield_scan_start_x = lev_fieldx - 1;
1604     playfield_scan_start_y = lev_fieldy - 1;
1605
1606     playfield_scan_delta_x = -1;
1607     playfield_scan_delta_y = -1;
1608   }
1609   else
1610   {
1611     playfield_scan_start_x = 0;
1612     playfield_scan_start_y = 0;
1613
1614     playfield_scan_delta_x = 1;
1615     playfield_scan_delta_y = 1;
1616   }
1617 }
1618
1619 static void InitPlayfieldScanMode(int mode)
1620 {
1621   game.use_reverse_scan_direction =
1622     (mode == CA_ARG_SCAN_MODE_REVERSE ? TRUE : FALSE);
1623
1624   InitPlayfieldScanModeVars();
1625 }
1626
1627 static int get_move_delay_from_stepsize(int move_stepsize)
1628 {
1629   move_stepsize =
1630     MIN(MAX(MOVE_STEPSIZE_MIN, move_stepsize), MOVE_STEPSIZE_MAX);
1631
1632   // make sure that stepsize value is always a power of 2
1633   move_stepsize = (1 << log_2(move_stepsize));
1634
1635   return TILEX / move_stepsize;
1636 }
1637
1638 static void SetPlayerMoveSpeed(struct PlayerInfo *player, int move_stepsize,
1639                                boolean init_game)
1640 {
1641   int player_nr = player->index_nr;
1642   int move_delay = get_move_delay_from_stepsize(move_stepsize);
1643   boolean cannot_move = (move_stepsize == STEPSIZE_NOT_MOVING ? TRUE : FALSE);
1644
1645   // do no immediately change move delay -- the player might just be moving
1646   player->move_delay_value_next = move_delay;
1647
1648   // information if player can move must be set separately
1649   player->cannot_move = cannot_move;
1650
1651   if (init_game)
1652   {
1653     player->move_delay       = game.initial_move_delay[player_nr];
1654     player->move_delay_value = game.initial_move_delay_value[player_nr];
1655
1656     player->move_delay_value_next = -1;
1657
1658     player->move_delay_reset_counter = 0;
1659   }
1660 }
1661
1662 void GetPlayerConfig(void)
1663 {
1664   GameFrameDelay = setup.game_frame_delay;
1665
1666   if (!audio.sound_available)
1667     setup.sound_simple = FALSE;
1668
1669   if (!audio.loops_available)
1670     setup.sound_loops = FALSE;
1671
1672   if (!audio.music_available)
1673     setup.sound_music = FALSE;
1674
1675   if (!video.fullscreen_available)
1676     setup.fullscreen = FALSE;
1677
1678   setup.sound = (setup.sound_simple || setup.sound_loops || setup.sound_music);
1679
1680   SetAudioMode(setup.sound);
1681 }
1682
1683 int GetElementFromGroupElement(int element)
1684 {
1685   if (IS_GROUP_ELEMENT(element))
1686   {
1687     struct ElementGroupInfo *group = element_info[element].group;
1688     int last_anim_random_frame = gfx.anim_random_frame;
1689     int element_pos;
1690
1691     if (group->choice_mode == ANIM_RANDOM)
1692       gfx.anim_random_frame = RND(group->num_elements_resolved);
1693
1694     element_pos = getAnimationFrame(group->num_elements_resolved, 1,
1695                                     group->choice_mode, 0,
1696                                     group->choice_pos);
1697
1698     if (group->choice_mode == ANIM_RANDOM)
1699       gfx.anim_random_frame = last_anim_random_frame;
1700
1701     group->choice_pos++;
1702
1703     element = group->element_resolved[element_pos];
1704   }
1705
1706   return element;
1707 }
1708
1709 static void IncrementSokobanFieldsNeeded(void)
1710 {
1711   if (level.sb_fields_needed)
1712     game.sokoban_fields_still_needed++;
1713 }
1714
1715 static void IncrementSokobanObjectsNeeded(void)
1716 {
1717   if (level.sb_objects_needed)
1718     game.sokoban_objects_still_needed++;
1719 }
1720
1721 static void DecrementSokobanFieldsNeeded(void)
1722 {
1723   if (game.sokoban_fields_still_needed > 0)
1724     game.sokoban_fields_still_needed--;
1725 }
1726
1727 static void DecrementSokobanObjectsNeeded(void)
1728 {
1729   if (game.sokoban_objects_still_needed > 0)
1730     game.sokoban_objects_still_needed--;
1731 }
1732
1733 static void InitPlayerField(int x, int y, int element, boolean init_game)
1734 {
1735   if (element == EL_SP_MURPHY)
1736   {
1737     if (init_game)
1738     {
1739       if (stored_player[0].present)
1740       {
1741         Tile[x][y] = EL_SP_MURPHY_CLONE;
1742
1743         return;
1744       }
1745       else
1746       {
1747         stored_player[0].initial_element = element;
1748         stored_player[0].use_murphy = TRUE;
1749
1750         if (!level.use_artwork_element[0])
1751           stored_player[0].artwork_element = EL_SP_MURPHY;
1752       }
1753
1754       Tile[x][y] = EL_PLAYER_1;
1755     }
1756   }
1757
1758   if (init_game)
1759   {
1760     struct PlayerInfo *player = &stored_player[Tile[x][y] - EL_PLAYER_1];
1761     int jx = player->jx, jy = player->jy;
1762
1763     player->present = TRUE;
1764
1765     player->block_last_field = (element == EL_SP_MURPHY ?
1766                                 level.sp_block_last_field :
1767                                 level.block_last_field);
1768
1769     // ---------- initialize player's last field block delay ------------------
1770
1771     // always start with reliable default value (no adjustment needed)
1772     player->block_delay_adjustment = 0;
1773
1774     // special case 1: in Supaplex, Murphy blocks last field one more frame
1775     if (player->block_last_field && element == EL_SP_MURPHY)
1776       player->block_delay_adjustment = 1;
1777
1778     // special case 2: in game engines before 3.1.1, blocking was different
1779     if (game.use_block_last_field_bug)
1780       player->block_delay_adjustment = (player->block_last_field ? -1 : 1);
1781
1782     if (!network.enabled || player->connected_network)
1783     {
1784       player->active = TRUE;
1785
1786       // remove potentially duplicate players
1787       if (IN_LEV_FIELD(jx, jy) && StorePlayer[jx][jy] == Tile[x][y])
1788         StorePlayer[jx][jy] = 0;
1789
1790       StorePlayer[x][y] = Tile[x][y];
1791
1792 #if DEBUG_INIT_PLAYER
1793       Debug("game:init:player", "- player element %d activated",
1794             player->element_nr);
1795       Debug("game:init:player", "  (local player is %d and currently %s)",
1796             local_player->element_nr,
1797             local_player->active ? "active" : "not active");
1798     }
1799 #endif
1800
1801     Tile[x][y] = EL_EMPTY;
1802
1803     player->jx = player->last_jx = x;
1804     player->jy = player->last_jy = y;
1805   }
1806
1807   // always check if player was just killed and should be reanimated
1808   {
1809     int player_nr = GET_PLAYER_NR(element);
1810     struct PlayerInfo *player = &stored_player[player_nr];
1811
1812     if (player->active && player->killed)
1813       player->reanimated = TRUE; // if player was just killed, reanimate him
1814   }
1815 }
1816
1817 static void InitField(int x, int y, boolean init_game)
1818 {
1819   int element = Tile[x][y];
1820
1821   switch (element)
1822   {
1823     case EL_SP_MURPHY:
1824     case EL_PLAYER_1:
1825     case EL_PLAYER_2:
1826     case EL_PLAYER_3:
1827     case EL_PLAYER_4:
1828       InitPlayerField(x, y, element, init_game);
1829       break;
1830
1831     case EL_SOKOBAN_FIELD_PLAYER:
1832       element = Tile[x][y] = EL_PLAYER_1;
1833       InitField(x, y, init_game);
1834
1835       element = Tile[x][y] = EL_SOKOBAN_FIELD_EMPTY;
1836       InitField(x, y, init_game);
1837       break;
1838
1839     case EL_SOKOBAN_FIELD_EMPTY:
1840       IncrementSokobanFieldsNeeded();
1841       break;
1842
1843     case EL_SOKOBAN_OBJECT:
1844       IncrementSokobanObjectsNeeded();
1845       break;
1846
1847     case EL_STONEBLOCK:
1848       if (x < lev_fieldx - 1 && Tile[x + 1][y] == EL_ACID)
1849         Tile[x][y] = EL_ACID_POOL_TOPLEFT;
1850       else if (x > 0 && Tile[x - 1][y] == EL_ACID)
1851         Tile[x][y] = EL_ACID_POOL_TOPRIGHT;
1852       else if (y > 0 && Tile[x][y - 1] == EL_ACID_POOL_TOPLEFT)
1853         Tile[x][y] = EL_ACID_POOL_BOTTOMLEFT;
1854       else if (y > 0 && Tile[x][y - 1] == EL_ACID)
1855         Tile[x][y] = EL_ACID_POOL_BOTTOM;
1856       else if (y > 0 && Tile[x][y - 1] == EL_ACID_POOL_TOPRIGHT)
1857         Tile[x][y] = EL_ACID_POOL_BOTTOMRIGHT;
1858       break;
1859
1860     case EL_BUG:
1861     case EL_BUG_RIGHT:
1862     case EL_BUG_UP:
1863     case EL_BUG_LEFT:
1864     case EL_BUG_DOWN:
1865     case EL_SPACESHIP:
1866     case EL_SPACESHIP_RIGHT:
1867     case EL_SPACESHIP_UP:
1868     case EL_SPACESHIP_LEFT:
1869     case EL_SPACESHIP_DOWN:
1870     case EL_BD_BUTTERFLY:
1871     case EL_BD_BUTTERFLY_RIGHT:
1872     case EL_BD_BUTTERFLY_UP:
1873     case EL_BD_BUTTERFLY_LEFT:
1874     case EL_BD_BUTTERFLY_DOWN:
1875     case EL_BD_FIREFLY:
1876     case EL_BD_FIREFLY_RIGHT:
1877     case EL_BD_FIREFLY_UP:
1878     case EL_BD_FIREFLY_LEFT:
1879     case EL_BD_FIREFLY_DOWN:
1880     case EL_PACMAN_RIGHT:
1881     case EL_PACMAN_UP:
1882     case EL_PACMAN_LEFT:
1883     case EL_PACMAN_DOWN:
1884     case EL_YAMYAM:
1885     case EL_YAMYAM_LEFT:
1886     case EL_YAMYAM_RIGHT:
1887     case EL_YAMYAM_UP:
1888     case EL_YAMYAM_DOWN:
1889     case EL_DARK_YAMYAM:
1890     case EL_ROBOT:
1891     case EL_PACMAN:
1892     case EL_SP_SNIKSNAK:
1893     case EL_SP_ELECTRON:
1894     case EL_MOLE:
1895     case EL_MOLE_LEFT:
1896     case EL_MOLE_RIGHT:
1897     case EL_MOLE_UP:
1898     case EL_MOLE_DOWN:
1899     case EL_SPRING_LEFT:
1900     case EL_SPRING_RIGHT:
1901       InitMovDir(x, y);
1902       break;
1903
1904     case EL_AMOEBA_FULL:
1905     case EL_BD_AMOEBA:
1906       InitAmoebaNr(x, y);
1907       break;
1908
1909     case EL_AMOEBA_DROP:
1910       if (y == lev_fieldy - 1)
1911       {
1912         Tile[x][y] = EL_AMOEBA_GROWING;
1913         Store[x][y] = EL_AMOEBA_WET;
1914       }
1915       break;
1916
1917     case EL_DYNAMITE_ACTIVE:
1918     case EL_SP_DISK_RED_ACTIVE:
1919     case EL_DYNABOMB_PLAYER_1_ACTIVE:
1920     case EL_DYNABOMB_PLAYER_2_ACTIVE:
1921     case EL_DYNABOMB_PLAYER_3_ACTIVE:
1922     case EL_DYNABOMB_PLAYER_4_ACTIVE:
1923       MovDelay[x][y] = 96;
1924       break;
1925
1926     case EL_EM_DYNAMITE_ACTIVE:
1927       MovDelay[x][y] = 32;
1928       break;
1929
1930     case EL_LAMP:
1931       game.lights_still_needed++;
1932       break;
1933
1934     case EL_PENGUIN:
1935       game.friends_still_needed++;
1936       break;
1937
1938     case EL_PIG:
1939     case EL_DRAGON:
1940       GfxDir[x][y] = MovDir[x][y] = 1 << RND(4);
1941       break;
1942
1943     case EL_CONVEYOR_BELT_1_SWITCH_LEFT:
1944     case EL_CONVEYOR_BELT_1_SWITCH_MIDDLE:
1945     case EL_CONVEYOR_BELT_1_SWITCH_RIGHT:
1946     case EL_CONVEYOR_BELT_2_SWITCH_LEFT:
1947     case EL_CONVEYOR_BELT_2_SWITCH_MIDDLE:
1948     case EL_CONVEYOR_BELT_2_SWITCH_RIGHT:
1949     case EL_CONVEYOR_BELT_3_SWITCH_LEFT:
1950     case EL_CONVEYOR_BELT_3_SWITCH_MIDDLE:
1951     case EL_CONVEYOR_BELT_3_SWITCH_RIGHT:
1952     case EL_CONVEYOR_BELT_4_SWITCH_LEFT:
1953     case EL_CONVEYOR_BELT_4_SWITCH_MIDDLE:
1954     case EL_CONVEYOR_BELT_4_SWITCH_RIGHT:
1955       if (init_game)
1956       {
1957         int belt_nr = getBeltNrFromBeltSwitchElement(Tile[x][y]);
1958         int belt_dir = getBeltDirFromBeltSwitchElement(Tile[x][y]);
1959         int belt_dir_nr = getBeltDirNrFromBeltSwitchElement(Tile[x][y]);
1960
1961         if (game.belt_dir_nr[belt_nr] == 3)     // initial value
1962         {
1963           game.belt_dir[belt_nr] = belt_dir;
1964           game.belt_dir_nr[belt_nr] = belt_dir_nr;
1965         }
1966         else    // more than one switch -- set it like the first switch
1967         {
1968           Tile[x][y] = Tile[x][y] - belt_dir_nr + game.belt_dir_nr[belt_nr];
1969         }
1970       }
1971       break;
1972
1973     case EL_LIGHT_SWITCH_ACTIVE:
1974       if (init_game)
1975         game.light_time_left = level.time_light * FRAMES_PER_SECOND;
1976       break;
1977
1978     case EL_INVISIBLE_STEELWALL:
1979     case EL_INVISIBLE_WALL:
1980     case EL_INVISIBLE_SAND:
1981       if (game.light_time_left > 0 ||
1982           game.lenses_time_left > 0)
1983         Tile[x][y] = getInvisibleActiveFromInvisibleElement(element);
1984       break;
1985
1986     case EL_EMC_MAGIC_BALL:
1987       if (game.ball_active)
1988         Tile[x][y] = EL_EMC_MAGIC_BALL_ACTIVE;
1989       break;
1990
1991     case EL_EMC_MAGIC_BALL_SWITCH:
1992       if (game.ball_active)
1993         Tile[x][y] = EL_EMC_MAGIC_BALL_SWITCH_ACTIVE;
1994       break;
1995
1996     case EL_TRIGGER_PLAYER:
1997     case EL_TRIGGER_ELEMENT:
1998     case EL_TRIGGER_CE_VALUE:
1999     case EL_TRIGGER_CE_SCORE:
2000     case EL_SELF:
2001     case EL_ANY_ELEMENT:
2002     case EL_CURRENT_CE_VALUE:
2003     case EL_CURRENT_CE_SCORE:
2004     case EL_PREV_CE_1:
2005     case EL_PREV_CE_2:
2006     case EL_PREV_CE_3:
2007     case EL_PREV_CE_4:
2008     case EL_PREV_CE_5:
2009     case EL_PREV_CE_6:
2010     case EL_PREV_CE_7:
2011     case EL_PREV_CE_8:
2012     case EL_NEXT_CE_1:
2013     case EL_NEXT_CE_2:
2014     case EL_NEXT_CE_3:
2015     case EL_NEXT_CE_4:
2016     case EL_NEXT_CE_5:
2017     case EL_NEXT_CE_6:
2018     case EL_NEXT_CE_7:
2019     case EL_NEXT_CE_8:
2020       // reference elements should not be used on the playfield
2021       Tile[x][y] = EL_EMPTY;
2022       break;
2023
2024     default:
2025       if (IS_CUSTOM_ELEMENT(element))
2026       {
2027         if (CAN_MOVE(element))
2028           InitMovDir(x, y);
2029
2030         if (!element_info[element].use_last_ce_value || init_game)
2031           CustomValue[x][y] = GET_NEW_CE_VALUE(Tile[x][y]);
2032       }
2033       else if (IS_GROUP_ELEMENT(element))
2034       {
2035         Tile[x][y] = GetElementFromGroupElement(element);
2036
2037         InitField(x, y, init_game);
2038       }
2039       else if (IS_EMPTY_ELEMENT(element))
2040       {
2041         GfxElementEmpty[x][y] = element;
2042         Tile[x][y] = EL_EMPTY;
2043
2044         if (element_info[element].use_gfx_element)
2045           game.use_masked_elements = TRUE;
2046       }
2047
2048       break;
2049   }
2050
2051   if (!init_game)
2052     CheckTriggeredElementChange(x, y, element, CE_CREATION_OF_X);
2053 }
2054
2055 static void InitField_WithBug1(int x, int y, boolean init_game)
2056 {
2057   InitField(x, y, init_game);
2058
2059   // not needed to call InitMovDir() -- already done by InitField()!
2060   if (game.engine_version < VERSION_IDENT(3,1,0,0) &&
2061       CAN_MOVE(Tile[x][y]))
2062     InitMovDir(x, y);
2063 }
2064
2065 static void InitField_WithBug2(int x, int y, boolean init_game)
2066 {
2067   int old_element = Tile[x][y];
2068
2069   InitField(x, y, init_game);
2070
2071   // not needed to call InitMovDir() -- already done by InitField()!
2072   if (game.engine_version < VERSION_IDENT(3,1,0,0) &&
2073       CAN_MOVE(old_element) &&
2074       (old_element < EL_MOLE_LEFT || old_element > EL_MOLE_DOWN))
2075     InitMovDir(x, y);
2076
2077   /* this case is in fact a combination of not less than three bugs:
2078      first, it calls InitMovDir() for elements that can move, although this is
2079      already done by InitField(); then, it checks the element that was at this
2080      field _before_ the call to InitField() (which can change it); lastly, it
2081      was not called for "mole with direction" elements, which were treated as
2082      "cannot move" due to (fixed) wrong element initialization in "src/init.c"
2083   */
2084 }
2085
2086 static int get_key_element_from_nr(int key_nr)
2087 {
2088   int key_base_element = (key_nr >= STD_NUM_KEYS ? EL_EMC_KEY_5 - STD_NUM_KEYS :
2089                           level.game_engine_type == GAME_ENGINE_TYPE_EM ?
2090                           EL_EM_KEY_1 : EL_KEY_1);
2091
2092   return key_base_element + key_nr;
2093 }
2094
2095 static int get_next_dropped_element(struct PlayerInfo *player)
2096 {
2097   return (player->inventory_size > 0 ?
2098           player->inventory_element[player->inventory_size - 1] :
2099           player->inventory_infinite_element != EL_UNDEFINED ?
2100           player->inventory_infinite_element :
2101           player->dynabombs_left > 0 ?
2102           EL_DYNABOMB_PLAYER_1_ACTIVE + player->index_nr :
2103           EL_UNDEFINED);
2104 }
2105
2106 static int get_inventory_element_from_pos(struct PlayerInfo *player, int pos)
2107 {
2108   // pos >= 0: get element from bottom of the stack;
2109   // pos <  0: get element from top of the stack
2110
2111   if (pos < 0)
2112   {
2113     int min_inventory_size = -pos;
2114     int inventory_pos = player->inventory_size - min_inventory_size;
2115     int min_dynabombs_left = min_inventory_size - player->inventory_size;
2116
2117     return (player->inventory_size >= min_inventory_size ?
2118             player->inventory_element[inventory_pos] :
2119             player->inventory_infinite_element != EL_UNDEFINED ?
2120             player->inventory_infinite_element :
2121             player->dynabombs_left >= min_dynabombs_left ?
2122             EL_DYNABOMB_PLAYER_1 + player->index_nr :
2123             EL_UNDEFINED);
2124   }
2125   else
2126   {
2127     int min_dynabombs_left = pos + 1;
2128     int min_inventory_size = pos + 1 - player->dynabombs_left;
2129     int inventory_pos = pos - player->dynabombs_left;
2130
2131     return (player->inventory_infinite_element != EL_UNDEFINED ?
2132             player->inventory_infinite_element :
2133             player->dynabombs_left >= min_dynabombs_left ?
2134             EL_DYNABOMB_PLAYER_1 + player->index_nr :
2135             player->inventory_size >= min_inventory_size ?
2136             player->inventory_element[inventory_pos] :
2137             EL_UNDEFINED);
2138   }
2139 }
2140
2141 static int compareGamePanelOrderInfo(const void *object1, const void *object2)
2142 {
2143   const struct GamePanelOrderInfo *gpo1 = (struct GamePanelOrderInfo *)object1;
2144   const struct GamePanelOrderInfo *gpo2 = (struct GamePanelOrderInfo *)object2;
2145   int compare_result;
2146
2147   if (gpo1->sort_priority != gpo2->sort_priority)
2148     compare_result = gpo1->sort_priority - gpo2->sort_priority;
2149   else
2150     compare_result = gpo1->nr - gpo2->nr;
2151
2152   return compare_result;
2153 }
2154
2155 int getPlayerInventorySize(int player_nr)
2156 {
2157   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
2158     return game_em.ply[player_nr]->dynamite;
2159   else if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
2160     return game_sp.red_disk_count;
2161   else
2162     return stored_player[player_nr].inventory_size;
2163 }
2164
2165 static void InitGameControlValues(void)
2166 {
2167   int i;
2168
2169   for (i = 0; game_panel_controls[i].nr != -1; i++)
2170   {
2171     struct GamePanelControlInfo *gpc = &game_panel_controls[i];
2172     struct GamePanelOrderInfo *gpo = &game_panel_order[i];
2173     struct TextPosInfo *pos = gpc->pos;
2174     int nr = gpc->nr;
2175     int type = gpc->type;
2176
2177     if (nr != i)
2178     {
2179       Error("'game_panel_controls' structure corrupted at %d", i);
2180
2181       Fail("this should not happen -- please debug");
2182     }
2183
2184     // force update of game controls after initialization
2185     gpc->value = gpc->last_value = -1;
2186     gpc->frame = gpc->last_frame = -1;
2187     gpc->gfx_frame = -1;
2188
2189     // determine panel value width for later calculation of alignment
2190     if (type == TYPE_INTEGER || type == TYPE_STRING)
2191     {
2192       pos->width = pos->size * getFontWidth(pos->font);
2193       pos->height = getFontHeight(pos->font);
2194     }
2195     else if (type == TYPE_ELEMENT)
2196     {
2197       pos->width = pos->size;
2198       pos->height = pos->size;
2199     }
2200
2201     // fill structure for game panel draw order
2202     gpo->nr = gpc->nr;
2203     gpo->sort_priority = pos->sort_priority;
2204   }
2205
2206   // sort game panel controls according to sort_priority and control number
2207   qsort(game_panel_order, NUM_GAME_PANEL_CONTROLS,
2208         sizeof(struct GamePanelOrderInfo), compareGamePanelOrderInfo);
2209 }
2210
2211 static void UpdatePlayfieldElementCount(void)
2212 {
2213   boolean use_element_count = FALSE;
2214   int i, j, x, y;
2215
2216   // first check if it is needed at all to calculate playfield element count
2217   for (i = GAME_PANEL_ELEMENT_COUNT_1; i <= GAME_PANEL_ELEMENT_COUNT_8; i++)
2218     if (!PANEL_DEACTIVATED(game_panel_controls[i].pos))
2219       use_element_count = TRUE;
2220
2221   if (!use_element_count)
2222     return;
2223
2224   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
2225     element_info[i].element_count = 0;
2226
2227   SCAN_PLAYFIELD(x, y)
2228   {
2229     element_info[Tile[x][y]].element_count++;
2230   }
2231
2232   for (i = 0; i < NUM_GROUP_ELEMENTS; i++)
2233     for (j = 0; j < MAX_NUM_ELEMENTS; j++)
2234       if (IS_IN_GROUP(j, i))
2235         element_info[EL_GROUP_START + i].element_count +=
2236           element_info[j].element_count;
2237 }
2238
2239 static void UpdateGameControlValues(void)
2240 {
2241   int i, k;
2242   int time = (game.LevelSolved ?
2243               game.LevelSolved_CountingTime :
2244               level.game_engine_type == GAME_ENGINE_TYPE_EM ?
2245               game_em.lev->time :
2246               level.game_engine_type == GAME_ENGINE_TYPE_SP ?
2247               game_sp.time_played :
2248               level.game_engine_type == GAME_ENGINE_TYPE_MM ?
2249               game_mm.energy_left :
2250               game.no_level_time_limit ? TimePlayed : TimeLeft);
2251   int score = (game.LevelSolved ?
2252                game.LevelSolved_CountingScore :
2253                level.game_engine_type == GAME_ENGINE_TYPE_EM ?
2254                game_em.lev->score :
2255                level.game_engine_type == GAME_ENGINE_TYPE_SP ?
2256                game_sp.score :
2257                level.game_engine_type == GAME_ENGINE_TYPE_MM ?
2258                game_mm.score :
2259                game.score);
2260   int gems = (level.game_engine_type == GAME_ENGINE_TYPE_EM ?
2261               game_em.lev->gems_needed :
2262               level.game_engine_type == GAME_ENGINE_TYPE_SP ?
2263               game_sp.infotrons_still_needed :
2264               level.game_engine_type == GAME_ENGINE_TYPE_MM ?
2265               game_mm.kettles_still_needed :
2266               game.gems_still_needed);
2267   int exit_closed = (level.game_engine_type == GAME_ENGINE_TYPE_EM ?
2268                      game_em.lev->gems_needed > 0 :
2269                      level.game_engine_type == GAME_ENGINE_TYPE_SP ?
2270                      game_sp.infotrons_still_needed > 0 :
2271                      level.game_engine_type == GAME_ENGINE_TYPE_MM ?
2272                      game_mm.kettles_still_needed > 0 ||
2273                      game_mm.lights_still_needed > 0 :
2274                      game.gems_still_needed > 0 ||
2275                      game.sokoban_fields_still_needed > 0 ||
2276                      game.sokoban_objects_still_needed > 0 ||
2277                      game.lights_still_needed > 0);
2278   int health = (game.LevelSolved ?
2279                 game.LevelSolved_CountingHealth :
2280                 level.game_engine_type == GAME_ENGINE_TYPE_MM ?
2281                 MM_HEALTH(game_mm.laser_overload_value) :
2282                 game.health);
2283   int sync_random_frame = INIT_GFX_RANDOM();    // random, but synchronized
2284
2285   UpdatePlayfieldElementCount();
2286
2287   // update game panel control values
2288
2289   // used instead of "level_nr" (for network games)
2290   game_panel_controls[GAME_PANEL_LEVEL_NUMBER].value = levelset.level_nr;
2291   game_panel_controls[GAME_PANEL_GEMS].value = gems;
2292
2293   game_panel_controls[GAME_PANEL_INVENTORY_COUNT].value = 0;
2294   for (i = 0; i < MAX_NUM_KEYS; i++)
2295     game_panel_controls[GAME_PANEL_KEY_1 + i].value = EL_EMPTY;
2296   game_panel_controls[GAME_PANEL_KEY_WHITE].value = EL_EMPTY;
2297   game_panel_controls[GAME_PANEL_KEY_WHITE_COUNT].value = 0;
2298
2299   if (game.centered_player_nr == -1)
2300   {
2301     for (i = 0; i < MAX_PLAYERS; i++)
2302     {
2303       // only one player in Supaplex game engine
2304       if (level.game_engine_type == GAME_ENGINE_TYPE_SP && i > 0)
2305         break;
2306
2307       for (k = 0; k < MAX_NUM_KEYS; k++)
2308       {
2309         if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
2310         {
2311           if (game_em.ply[i]->keys & (1 << k))
2312             game_panel_controls[GAME_PANEL_KEY_1 + k].value =
2313               get_key_element_from_nr(k);
2314         }
2315         else if (stored_player[i].key[k])
2316           game_panel_controls[GAME_PANEL_KEY_1 + k].value =
2317             get_key_element_from_nr(k);
2318       }
2319
2320       game_panel_controls[GAME_PANEL_INVENTORY_COUNT].value +=
2321         getPlayerInventorySize(i);
2322
2323       if (stored_player[i].num_white_keys > 0)
2324         game_panel_controls[GAME_PANEL_KEY_WHITE].value =
2325           EL_DC_KEY_WHITE;
2326
2327       game_panel_controls[GAME_PANEL_KEY_WHITE_COUNT].value +=
2328         stored_player[i].num_white_keys;
2329     }
2330   }
2331   else
2332   {
2333     int player_nr = game.centered_player_nr;
2334
2335     for (k = 0; k < MAX_NUM_KEYS; k++)
2336     {
2337       if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
2338       {
2339         if (game_em.ply[player_nr]->keys & (1 << k))
2340           game_panel_controls[GAME_PANEL_KEY_1 + k].value =
2341             get_key_element_from_nr(k);
2342       }
2343       else if (stored_player[player_nr].key[k])
2344         game_panel_controls[GAME_PANEL_KEY_1 + k].value =
2345           get_key_element_from_nr(k);
2346     }
2347
2348     game_panel_controls[GAME_PANEL_INVENTORY_COUNT].value +=
2349       getPlayerInventorySize(player_nr);
2350
2351     if (stored_player[player_nr].num_white_keys > 0)
2352       game_panel_controls[GAME_PANEL_KEY_WHITE].value = EL_DC_KEY_WHITE;
2353
2354     game_panel_controls[GAME_PANEL_KEY_WHITE_COUNT].value +=
2355       stored_player[player_nr].num_white_keys;
2356   }
2357
2358   // re-arrange keys on game panel, if needed or if defined by style settings
2359   for (i = 0; i < MAX_NUM_KEYS + 1; i++)        // all normal keys + white key
2360   {
2361     int nr = GAME_PANEL_KEY_1 + i;
2362     struct GamePanelControlInfo *gpc = &game_panel_controls[nr];
2363     struct TextPosInfo *pos = gpc->pos;
2364
2365     // skip check if key is not in the player's inventory
2366     if (gpc->value == EL_EMPTY)
2367       continue;
2368
2369     // check if keys should be arranged on panel from left to right
2370     if (pos->style == STYLE_LEFTMOST_POSITION)
2371     {
2372       // check previous key positions (left from current key)
2373       for (k = 0; k < i; k++)
2374       {
2375         int nr_new = GAME_PANEL_KEY_1 + k;
2376
2377         if (game_panel_controls[nr_new].value == EL_EMPTY)
2378         {
2379           game_panel_controls[nr_new].value = gpc->value;
2380           gpc->value = EL_EMPTY;
2381
2382           break;
2383         }
2384       }
2385     }
2386
2387     // check if "undefined" keys can be placed at some other position
2388     if (pos->x == -1 && pos->y == -1)
2389     {
2390       int nr_new = GAME_PANEL_KEY_1 + i % STD_NUM_KEYS;
2391
2392       // 1st try: display key at the same position as normal or EM keys
2393       if (game_panel_controls[nr_new].value == EL_EMPTY)
2394       {
2395         game_panel_controls[nr_new].value = gpc->value;
2396       }
2397       else
2398       {
2399         // 2nd try: display key at the next free position in the key panel
2400         for (k = 0; k < STD_NUM_KEYS; k++)
2401         {
2402           nr_new = GAME_PANEL_KEY_1 + k;
2403
2404           if (game_panel_controls[nr_new].value == EL_EMPTY)
2405           {
2406             game_panel_controls[nr_new].value = gpc->value;
2407
2408             break;
2409           }
2410         }
2411       }
2412     }
2413   }
2414
2415   for (i = 0; i < NUM_PANEL_INVENTORY; i++)
2416   {
2417     game_panel_controls[GAME_PANEL_INVENTORY_FIRST_1 + i].value =
2418       get_inventory_element_from_pos(local_player, i);
2419     game_panel_controls[GAME_PANEL_INVENTORY_LAST_1 + i].value =
2420       get_inventory_element_from_pos(local_player, -i - 1);
2421   }
2422
2423   game_panel_controls[GAME_PANEL_SCORE].value = score;
2424   game_panel_controls[GAME_PANEL_HIGHSCORE].value = scores.entry[0].score;
2425
2426   game_panel_controls[GAME_PANEL_TIME].value = time;
2427
2428   game_panel_controls[GAME_PANEL_TIME_HH].value = time / 3600;
2429   game_panel_controls[GAME_PANEL_TIME_MM].value = (time / 60) % 60;
2430   game_panel_controls[GAME_PANEL_TIME_SS].value = time % 60;
2431
2432   if (level.time == 0)
2433     game_panel_controls[GAME_PANEL_TIME_ANIM].value = 100;
2434   else
2435     game_panel_controls[GAME_PANEL_TIME_ANIM].value = time * 100 / level.time;
2436
2437   game_panel_controls[GAME_PANEL_HEALTH].value = health;
2438   game_panel_controls[GAME_PANEL_HEALTH_ANIM].value = health;
2439
2440   game_panel_controls[GAME_PANEL_FRAME].value = FrameCounter;
2441
2442   game_panel_controls[GAME_PANEL_SHIELD_NORMAL].value =
2443     (local_player->shield_normal_time_left > 0 ? EL_SHIELD_NORMAL_ACTIVE :
2444      EL_EMPTY);
2445   game_panel_controls[GAME_PANEL_SHIELD_NORMAL_TIME].value =
2446     local_player->shield_normal_time_left;
2447   game_panel_controls[GAME_PANEL_SHIELD_DEADLY].value =
2448     (local_player->shield_deadly_time_left > 0 ? EL_SHIELD_DEADLY_ACTIVE :
2449      EL_EMPTY);
2450   game_panel_controls[GAME_PANEL_SHIELD_DEADLY_TIME].value =
2451     local_player->shield_deadly_time_left;
2452
2453   game_panel_controls[GAME_PANEL_EXIT].value =
2454     (exit_closed ? EL_EXIT_CLOSED : EL_EXIT_OPEN);
2455
2456   game_panel_controls[GAME_PANEL_EMC_MAGIC_BALL].value =
2457     (game.ball_active ? EL_EMC_MAGIC_BALL_ACTIVE : EL_EMC_MAGIC_BALL);
2458   game_panel_controls[GAME_PANEL_EMC_MAGIC_BALL_SWITCH].value =
2459     (game.ball_active ? EL_EMC_MAGIC_BALL_SWITCH_ACTIVE :
2460      EL_EMC_MAGIC_BALL_SWITCH);
2461
2462   game_panel_controls[GAME_PANEL_LIGHT_SWITCH].value =
2463     (game.light_time_left > 0 ? EL_LIGHT_SWITCH_ACTIVE : EL_LIGHT_SWITCH);
2464   game_panel_controls[GAME_PANEL_LIGHT_SWITCH_TIME].value =
2465     game.light_time_left;
2466
2467   game_panel_controls[GAME_PANEL_TIMEGATE_SWITCH].value =
2468     (game.timegate_time_left > 0 ? EL_TIMEGATE_OPEN : EL_TIMEGATE_CLOSED);
2469   game_panel_controls[GAME_PANEL_TIMEGATE_SWITCH_TIME].value =
2470     game.timegate_time_left;
2471
2472   game_panel_controls[GAME_PANEL_SWITCHGATE_SWITCH].value =
2473     EL_SWITCHGATE_SWITCH_UP + game.switchgate_pos;
2474
2475   game_panel_controls[GAME_PANEL_EMC_LENSES].value =
2476     (game.lenses_time_left > 0 ? EL_EMC_LENSES : EL_EMPTY);
2477   game_panel_controls[GAME_PANEL_EMC_LENSES_TIME].value =
2478     game.lenses_time_left;
2479
2480   game_panel_controls[GAME_PANEL_EMC_MAGNIFIER].value =
2481     (game.magnify_time_left > 0 ? EL_EMC_MAGNIFIER : EL_EMPTY);
2482   game_panel_controls[GAME_PANEL_EMC_MAGNIFIER_TIME].value =
2483     game.magnify_time_left;
2484
2485   game_panel_controls[GAME_PANEL_BALLOON_SWITCH].value =
2486     (game.wind_direction == MV_LEFT  ? EL_BALLOON_SWITCH_LEFT  :
2487      game.wind_direction == MV_RIGHT ? EL_BALLOON_SWITCH_RIGHT :
2488      game.wind_direction == MV_UP    ? EL_BALLOON_SWITCH_UP    :
2489      game.wind_direction == MV_DOWN  ? EL_BALLOON_SWITCH_DOWN  :
2490      EL_BALLOON_SWITCH_NONE);
2491
2492   game_panel_controls[GAME_PANEL_DYNABOMB_NUMBER].value =
2493     local_player->dynabomb_count;
2494   game_panel_controls[GAME_PANEL_DYNABOMB_SIZE].value =
2495     local_player->dynabomb_size;
2496   game_panel_controls[GAME_PANEL_DYNABOMB_POWER].value =
2497     (local_player->dynabomb_xl ? EL_DYNABOMB_INCREASE_POWER : EL_EMPTY);
2498
2499   game_panel_controls[GAME_PANEL_PENGUINS].value =
2500     game.friends_still_needed;
2501
2502   game_panel_controls[GAME_PANEL_SOKOBAN_OBJECTS].value =
2503     game.sokoban_objects_still_needed;
2504   game_panel_controls[GAME_PANEL_SOKOBAN_FIELDS].value =
2505     game.sokoban_fields_still_needed;
2506
2507   game_panel_controls[GAME_PANEL_ROBOT_WHEEL].value =
2508     (game.robot_wheel_active ? EL_ROBOT_WHEEL_ACTIVE : EL_ROBOT_WHEEL);
2509
2510   for (i = 0; i < NUM_BELTS; i++)
2511   {
2512     game_panel_controls[GAME_PANEL_CONVEYOR_BELT_1 + i].value =
2513       (game.belt_dir[i] != MV_NONE ? EL_CONVEYOR_BELT_1_MIDDLE_ACTIVE :
2514        EL_CONVEYOR_BELT_1_MIDDLE) + i;
2515     game_panel_controls[GAME_PANEL_CONVEYOR_BELT_1_SWITCH + i].value =
2516       getBeltSwitchElementFromBeltNrAndBeltDir(i, game.belt_dir[i]);
2517   }
2518
2519   game_panel_controls[GAME_PANEL_MAGIC_WALL].value =
2520     (game.magic_wall_active ? EL_MAGIC_WALL_ACTIVE : EL_MAGIC_WALL);
2521   game_panel_controls[GAME_PANEL_MAGIC_WALL_TIME].value =
2522     game.magic_wall_time_left;
2523
2524   game_panel_controls[GAME_PANEL_GRAVITY_STATE].value =
2525     local_player->gravity;
2526
2527   for (i = 0; i < NUM_PANEL_GRAPHICS; i++)
2528     game_panel_controls[GAME_PANEL_GRAPHIC_1 + i].value = EL_GRAPHIC_1 + i;
2529
2530   for (i = 0; i < NUM_PANEL_ELEMENTS; i++)
2531     game_panel_controls[GAME_PANEL_ELEMENT_1 + i].value =
2532       (IS_DRAWABLE_ELEMENT(game.panel.element[i].id) ?
2533        game.panel.element[i].id : EL_UNDEFINED);
2534
2535   for (i = 0; i < NUM_PANEL_ELEMENTS; i++)
2536     game_panel_controls[GAME_PANEL_ELEMENT_COUNT_1 + i].value =
2537       (IS_VALID_ELEMENT(game.panel.element_count[i].id) ?
2538        element_info[game.panel.element_count[i].id].element_count : 0);
2539
2540   for (i = 0; i < NUM_PANEL_CE_SCORE; i++)
2541     game_panel_controls[GAME_PANEL_CE_SCORE_1 + i].value =
2542       (IS_CUSTOM_ELEMENT(game.panel.ce_score[i].id) ?
2543        element_info[game.panel.ce_score[i].id].collect_score : 0);
2544
2545   for (i = 0; i < NUM_PANEL_CE_SCORE; i++)
2546     game_panel_controls[GAME_PANEL_CE_SCORE_1_ELEMENT + i].value =
2547       (IS_CUSTOM_ELEMENT(game.panel.ce_score_element[i].id) ?
2548        element_info[game.panel.ce_score_element[i].id].collect_score :
2549        EL_UNDEFINED);
2550
2551   game_panel_controls[GAME_PANEL_PLAYER_NAME].value = 0;
2552   game_panel_controls[GAME_PANEL_LEVEL_NAME].value = 0;
2553   game_panel_controls[GAME_PANEL_LEVEL_AUTHOR].value = 0;
2554
2555   // update game panel control frames
2556
2557   for (i = 0; game_panel_controls[i].nr != -1; i++)
2558   {
2559     struct GamePanelControlInfo *gpc = &game_panel_controls[i];
2560
2561     if (gpc->type == TYPE_ELEMENT)
2562     {
2563       if (gpc->value != EL_UNDEFINED && gpc->value != EL_EMPTY)
2564       {
2565         int last_anim_random_frame = gfx.anim_random_frame;
2566         int element = gpc->value;
2567         int graphic = el2panelimg(element);
2568         int init_gfx_random = (graphic_info[graphic].anim_global_sync ?
2569                                sync_random_frame :
2570                                graphic_info[graphic].anim_global_anim_sync ?
2571                                getGlobalAnimSyncFrame() : INIT_GFX_RANDOM());
2572
2573         if (gpc->value != gpc->last_value)
2574         {
2575           gpc->gfx_frame = 0;
2576           gpc->gfx_random = init_gfx_random;
2577         }
2578         else
2579         {
2580           gpc->gfx_frame++;
2581
2582           if (ANIM_MODE(graphic) == ANIM_RANDOM &&
2583               IS_NEXT_FRAME(gpc->gfx_frame, graphic))
2584             gpc->gfx_random = init_gfx_random;
2585         }
2586
2587         if (ANIM_MODE(graphic) == ANIM_RANDOM)
2588           gfx.anim_random_frame = gpc->gfx_random;
2589
2590         if (ANIM_MODE(graphic) == ANIM_CE_SCORE)
2591           gpc->gfx_frame = element_info[element].collect_score;
2592
2593         gpc->frame = getGraphicAnimationFrame(graphic, gpc->gfx_frame);
2594
2595         if (ANIM_MODE(graphic) == ANIM_RANDOM)
2596           gfx.anim_random_frame = last_anim_random_frame;
2597       }
2598     }
2599     else if (gpc->type == TYPE_GRAPHIC)
2600     {
2601       if (gpc->graphic != IMG_UNDEFINED)
2602       {
2603         int last_anim_random_frame = gfx.anim_random_frame;
2604         int graphic = gpc->graphic;
2605         int init_gfx_random = (graphic_info[graphic].anim_global_sync ?
2606                                sync_random_frame :
2607                                graphic_info[graphic].anim_global_anim_sync ?
2608                                getGlobalAnimSyncFrame() : INIT_GFX_RANDOM());
2609
2610         if (gpc->value != gpc->last_value)
2611         {
2612           gpc->gfx_frame = 0;
2613           gpc->gfx_random = init_gfx_random;
2614         }
2615         else
2616         {
2617           gpc->gfx_frame++;
2618
2619           if (ANIM_MODE(graphic) == ANIM_RANDOM &&
2620               IS_NEXT_FRAME(gpc->gfx_frame, graphic))
2621             gpc->gfx_random = init_gfx_random;
2622         }
2623
2624         if (ANIM_MODE(graphic) == ANIM_RANDOM)
2625           gfx.anim_random_frame = gpc->gfx_random;
2626
2627         gpc->frame = getGraphicAnimationFrame(graphic, gpc->gfx_frame);
2628
2629         if (ANIM_MODE(graphic) == ANIM_RANDOM)
2630           gfx.anim_random_frame = last_anim_random_frame;
2631       }
2632     }
2633   }
2634 }
2635
2636 static void DisplayGameControlValues(void)
2637 {
2638   boolean redraw_panel = FALSE;
2639   int i;
2640
2641   for (i = 0; game_panel_controls[i].nr != -1; i++)
2642   {
2643     struct GamePanelControlInfo *gpc = &game_panel_controls[i];
2644
2645     if (PANEL_DEACTIVATED(gpc->pos))
2646       continue;
2647
2648     if (gpc->value == gpc->last_value &&
2649         gpc->frame == gpc->last_frame)
2650       continue;
2651
2652     redraw_panel = TRUE;
2653   }
2654
2655   if (!redraw_panel)
2656     return;
2657
2658   // copy default game door content to main double buffer
2659
2660   // !!! CHECK AGAIN !!!
2661   SetPanelBackground();
2662   // SetDoorBackgroundImage(IMG_BACKGROUND_PANEL);
2663   DrawBackground(DX, DY, DXSIZE, DYSIZE);
2664
2665   // redraw game control buttons
2666   RedrawGameButtons();
2667
2668   SetGameStatus(GAME_MODE_PSEUDO_PANEL);
2669
2670   for (i = 0; i < NUM_GAME_PANEL_CONTROLS; i++)
2671   {
2672     int nr = game_panel_order[i].nr;
2673     struct GamePanelControlInfo *gpc = &game_panel_controls[nr];
2674     struct TextPosInfo *pos = gpc->pos;
2675     int type = gpc->type;
2676     int value = gpc->value;
2677     int frame = gpc->frame;
2678     int size = pos->size;
2679     int font = pos->font;
2680     boolean draw_masked = pos->draw_masked;
2681     int mask_mode = (draw_masked ? BLIT_MASKED : BLIT_OPAQUE);
2682
2683     if (PANEL_DEACTIVATED(pos))
2684       continue;
2685
2686     if (pos->class == get_hash_from_key("extra_panel_items") &&
2687         !setup.prefer_extra_panel_items)
2688       continue;
2689
2690     gpc->last_value = value;
2691     gpc->last_frame = frame;
2692
2693     if (type == TYPE_INTEGER)
2694     {
2695       if (nr == GAME_PANEL_LEVEL_NUMBER ||
2696           nr == GAME_PANEL_INVENTORY_COUNT ||
2697           nr == GAME_PANEL_SCORE ||
2698           nr == GAME_PANEL_HIGHSCORE ||
2699           nr == GAME_PANEL_TIME)
2700       {
2701         boolean use_dynamic_size = (size == -1 ? TRUE : FALSE);
2702
2703         if (use_dynamic_size)           // use dynamic number of digits
2704         {
2705           int value_change = (nr == GAME_PANEL_LEVEL_NUMBER ? 100 :
2706                               nr == GAME_PANEL_INVENTORY_COUNT ||
2707                               nr == GAME_PANEL_TIME ? 1000 : 100000);
2708           int size_add = (nr == GAME_PANEL_LEVEL_NUMBER ||
2709                           nr == GAME_PANEL_INVENTORY_COUNT ||
2710                           nr == GAME_PANEL_TIME ? 1 : 2);
2711           int size1 = (nr == GAME_PANEL_LEVEL_NUMBER ? 2 :
2712                        nr == GAME_PANEL_INVENTORY_COUNT ||
2713                        nr == GAME_PANEL_TIME ? 3 : 5);
2714           int size2 = size1 + size_add;
2715           int font1 = pos->font;
2716           int font2 = pos->font_alt;
2717
2718           size = (value < value_change ? size1 : size2);
2719           font = (value < value_change ? font1 : font2);
2720         }
2721       }
2722
2723       // correct text size if "digits" is zero or less
2724       if (size <= 0)
2725         size = strlen(int2str(value, size));
2726
2727       // dynamically correct text alignment
2728       pos->width = size * getFontWidth(font);
2729
2730       DrawTextExt(drawto, PANEL_XPOS(pos), PANEL_YPOS(pos),
2731                   int2str(value, size), font, mask_mode);
2732     }
2733     else if (type == TYPE_ELEMENT)
2734     {
2735       int element, graphic;
2736       Bitmap *src_bitmap;
2737       int src_x, src_y;
2738       int width, height;
2739       int dst_x = PANEL_XPOS(pos);
2740       int dst_y = PANEL_YPOS(pos);
2741
2742       if (value != EL_UNDEFINED && value != EL_EMPTY)
2743       {
2744         element = value;
2745         graphic = el2panelimg(value);
2746
2747 #if 0
2748         Debug("game:DisplayGameControlValues", "%d, '%s' [%d]",
2749               element, EL_NAME(element), size);
2750 #endif
2751
2752         if (element >= EL_GRAPHIC_1 && element <= EL_GRAPHIC_8 && size == 0)
2753           size = TILESIZE;
2754
2755         getSizedGraphicSource(graphic, frame, size, &src_bitmap,
2756                               &src_x, &src_y);
2757
2758         width  = graphic_info[graphic].width  * size / TILESIZE;
2759         height = graphic_info[graphic].height * size / TILESIZE;
2760
2761         if (draw_masked)
2762           BlitBitmapMasked(src_bitmap, drawto, src_x, src_y, width, height,
2763                            dst_x, dst_y);
2764         else
2765           BlitBitmap(src_bitmap, drawto, src_x, src_y, width, height,
2766                      dst_x, dst_y);
2767       }
2768     }
2769     else if (type == TYPE_GRAPHIC)
2770     {
2771       int graphic        = gpc->graphic;
2772       int graphic_active = gpc->graphic_active;
2773       Bitmap *src_bitmap;
2774       int src_x, src_y;
2775       int width, height;
2776       int dst_x = PANEL_XPOS(pos);
2777       int dst_y = PANEL_YPOS(pos);
2778       boolean skip = (pos->class == get_hash_from_key("mm_engine_only") &&
2779                       level.game_engine_type != GAME_ENGINE_TYPE_MM);
2780
2781       if (graphic != IMG_UNDEFINED && !skip)
2782       {
2783         if (pos->style == STYLE_REVERSE)
2784           value = 100 - value;
2785
2786         getGraphicSource(graphic_active, frame, &src_bitmap, &src_x, &src_y);
2787
2788         if (pos->direction & MV_HORIZONTAL)
2789         {
2790           width  = graphic_info[graphic_active].width * value / 100;
2791           height = graphic_info[graphic_active].height;
2792
2793           if (pos->direction == MV_LEFT)
2794           {
2795             src_x += graphic_info[graphic_active].width - width;
2796             dst_x += graphic_info[graphic_active].width - width;
2797           }
2798         }
2799         else
2800         {
2801           width  = graphic_info[graphic_active].width;
2802           height = graphic_info[graphic_active].height * value / 100;
2803
2804           if (pos->direction == MV_UP)
2805           {
2806             src_y += graphic_info[graphic_active].height - height;
2807             dst_y += graphic_info[graphic_active].height - height;
2808           }
2809         }
2810
2811         if (draw_masked)
2812           BlitBitmapMasked(src_bitmap, drawto, src_x, src_y, width, height,
2813                            dst_x, dst_y);
2814         else
2815           BlitBitmap(src_bitmap, drawto, src_x, src_y, width, height,
2816                      dst_x, dst_y);
2817
2818         getGraphicSource(graphic, frame, &src_bitmap, &src_x, &src_y);
2819
2820         if (pos->direction & MV_HORIZONTAL)
2821         {
2822           if (pos->direction == MV_RIGHT)
2823           {
2824             src_x += width;
2825             dst_x += width;
2826           }
2827           else
2828           {
2829             dst_x = PANEL_XPOS(pos);
2830           }
2831
2832           width = graphic_info[graphic].width - width;
2833         }
2834         else
2835         {
2836           if (pos->direction == MV_DOWN)
2837           {
2838             src_y += height;
2839             dst_y += height;
2840           }
2841           else
2842           {
2843             dst_y = PANEL_YPOS(pos);
2844           }
2845
2846           height = graphic_info[graphic].height - height;
2847         }
2848
2849         if (draw_masked)
2850           BlitBitmapMasked(src_bitmap, drawto, src_x, src_y, width, height,
2851                            dst_x, dst_y);
2852         else
2853           BlitBitmap(src_bitmap, drawto, src_x, src_y, width, height,
2854                      dst_x, dst_y);
2855       }
2856     }
2857     else if (type == TYPE_STRING)
2858     {
2859       boolean active = (value != 0);
2860       char *state_normal = "off";
2861       char *state_active = "on";
2862       char *state = (active ? state_active : state_normal);
2863       char *s = (nr == GAME_PANEL_GRAVITY_STATE ? state :
2864                  nr == GAME_PANEL_PLAYER_NAME   ? setup.player_name :
2865                  nr == GAME_PANEL_LEVEL_NAME    ? level.name :
2866                  nr == GAME_PANEL_LEVEL_AUTHOR  ? level.author : NULL);
2867
2868       if (nr == GAME_PANEL_GRAVITY_STATE)
2869       {
2870         int font1 = pos->font;          // (used for normal state)
2871         int font2 = pos->font_alt;      // (used for active state)
2872
2873         font = (active ? font2 : font1);
2874       }
2875
2876       if (s != NULL)
2877       {
2878         char *s_cut;
2879
2880         if (size <= 0)
2881         {
2882           // don't truncate output if "chars" is zero or less
2883           size = strlen(s);
2884
2885           // dynamically correct text alignment
2886           pos->width = size * getFontWidth(font);
2887         }
2888
2889         s_cut = getStringCopyN(s, size);
2890
2891         DrawTextExt(drawto, PANEL_XPOS(pos), PANEL_YPOS(pos),
2892                     s_cut, font, mask_mode);
2893
2894         free(s_cut);
2895       }
2896     }
2897
2898     redraw_mask |= REDRAW_DOOR_1;
2899   }
2900
2901   SetGameStatus(GAME_MODE_PLAYING);
2902 }
2903
2904 void UpdateAndDisplayGameControlValues(void)
2905 {
2906   if (tape.deactivate_display)
2907     return;
2908
2909   UpdateGameControlValues();
2910   DisplayGameControlValues();
2911 }
2912
2913 void UpdateGameDoorValues(void)
2914 {
2915   UpdateGameControlValues();
2916 }
2917
2918 void DrawGameDoorValues(void)
2919 {
2920   DisplayGameControlValues();
2921 }
2922
2923
2924 // ============================================================================
2925 // InitGameEngine()
2926 // ----------------------------------------------------------------------------
2927 // initialize game engine due to level / tape version number
2928 // ============================================================================
2929
2930 static void InitGameEngine(void)
2931 {
2932   int i, j, k, l, x, y;
2933
2934   // set game engine from tape file when re-playing, else from level file
2935   game.engine_version = (tape.playing ? tape.engine_version :
2936                          level.game_version);
2937
2938   // set single or multi-player game mode (needed for re-playing tapes)
2939   game.team_mode = setup.team_mode;
2940
2941   if (tape.playing)
2942   {
2943     int num_players = 0;
2944
2945     for (i = 0; i < MAX_PLAYERS; i++)
2946       if (tape.player_participates[i])
2947         num_players++;
2948
2949     // multi-player tapes contain input data for more than one player
2950     game.team_mode = (num_players > 1);
2951   }
2952
2953 #if 0
2954   Debug("game:init:level", "level %d: level.game_version  == %06d", level_nr,
2955         level.game_version);
2956   Debug("game:init:level", "          tape.file_version   == %06d",
2957         tape.file_version);
2958   Debug("game:init:level", "          tape.game_version   == %06d",
2959         tape.game_version);
2960   Debug("game:init:level", "          tape.engine_version == %06d",
2961         tape.engine_version);
2962   Debug("game:init:level", "       => game.engine_version == %06d [tape mode: %s]",
2963         game.engine_version, (tape.playing ? "PLAYING" : "RECORDING"));
2964 #endif
2965
2966   // --------------------------------------------------------------------------
2967   // set flags for bugs and changes according to active game engine version
2968   // --------------------------------------------------------------------------
2969
2970   /*
2971     Summary of bugfix:
2972     Fixed property "can fall" for run-time element "EL_AMOEBA_DROPPING"
2973
2974     Bug was introduced in version:
2975     2.0.1
2976
2977     Bug was fixed in version:
2978     4.2.0.0
2979
2980     Description:
2981     In version 2.0.1, a new run-time element "EL_AMOEBA_DROPPING" was added,
2982     but the property "can fall" was missing, which caused some levels to be
2983     unsolvable. This was fixed in version 4.2.0.0.
2984
2985     Affected levels/tapes:
2986     An example for a tape that was fixed by this bugfix is tape 029 from the
2987     level set "rnd_sam_bateman".
2988     The wrong behaviour will still be used for all levels or tapes that were
2989     created/recorded with it. An example for this is tape 023 from the level
2990     set "rnd_gerhard_haeusler", which was recorded with a buggy game engine.
2991   */
2992
2993   boolean use_amoeba_dropping_cannot_fall_bug =
2994     ((game.engine_version >= VERSION_IDENT(2,0,1,0) &&
2995       game.engine_version <  VERSION_IDENT(4,2,0,0)) ||
2996      (tape.playing &&
2997       tape.game_version >= VERSION_IDENT(2,0,1,0) &&
2998       tape.game_version <  VERSION_IDENT(4,2,0,0)));
2999
3000   /*
3001     Summary of bugfix/change:
3002     Fixed move speed of elements entering or leaving magic wall.
3003
3004     Fixed/changed in version:
3005     2.0.1
3006
3007     Description:
3008     Before 2.0.1, move speed of elements entering or leaving magic wall was
3009     twice as fast as it is now.
3010     Since 2.0.1, this is set to a lower value by using move_stepsize_list[].
3011
3012     Affected levels/tapes:
3013     The first condition is generally needed for all levels/tapes before version
3014     2.0.1, which might use the old behaviour before it was changed; known tapes
3015     that are affected: Tape 014 from the level set "rnd_conor_mancone".
3016     The second condition is an exception from the above case and is needed for
3017     the special case of tapes recorded with game (not engine!) version 2.0.1 or
3018     above, but before it was known that this change would break tapes like the
3019     above and was fixed in 4.2.0.0, so that the changed behaviour was active
3020     although the engine version while recording maybe was before 2.0.1. There
3021     are a lot of tapes that are affected by this exception, like tape 006 from
3022     the level set "rnd_conor_mancone".
3023   */
3024
3025   boolean use_old_move_stepsize_for_magic_wall =
3026     (game.engine_version < VERSION_IDENT(2,0,1,0) &&
3027      !(tape.playing &&
3028        tape.game_version >= VERSION_IDENT(2,0,1,0) &&
3029        tape.game_version <  VERSION_IDENT(4,2,0,0)));
3030
3031   /*
3032     Summary of bugfix/change:
3033     Fixed handling for custom elements that change when pushed by the player.
3034
3035     Fixed/changed in version:
3036     3.1.0
3037
3038     Description:
3039     Before 3.1.0, custom elements that "change when pushing" changed directly
3040     after the player started pushing them (until then handled in "DigField()").
3041     Since 3.1.0, these custom elements are not changed until the "pushing"
3042     move of the element is finished (now handled in "ContinueMoving()").
3043
3044     Affected levels/tapes:
3045     The first condition is generally needed for all levels/tapes before version
3046     3.1.0, which might use the old behaviour before it was changed; known tapes
3047     that are affected are some tapes from the level set "Walpurgis Gardens" by
3048     Jamie Cullen.
3049     The second condition is an exception from the above case and is needed for
3050     the special case of tapes recorded with game (not engine!) version 3.1.0 or
3051     above (including some development versions of 3.1.0), but before it was
3052     known that this change would break tapes like the above and was fixed in
3053     3.1.1, so that the changed behaviour was active although the engine version
3054     while recording maybe was before 3.1.0. There is at least one tape that is
3055     affected by this exception, which is the tape for the one-level set "Bug
3056     Machine" by Juergen Bonhagen.
3057   */
3058
3059   game.use_change_when_pushing_bug =
3060     (game.engine_version < VERSION_IDENT(3,1,0,0) &&
3061      !(tape.playing &&
3062        tape.game_version >= VERSION_IDENT(3,1,0,0) &&
3063        tape.game_version <  VERSION_IDENT(3,1,1,0)));
3064
3065   /*
3066     Summary of bugfix/change:
3067     Fixed handling for blocking the field the player leaves when moving.
3068
3069     Fixed/changed in version:
3070     3.1.1
3071
3072     Description:
3073     Before 3.1.1, when "block last field when moving" was enabled, the field
3074     the player is leaving when moving was blocked for the time of the move,
3075     and was directly unblocked afterwards. This resulted in the last field
3076     being blocked for exactly one less than the number of frames of one player
3077     move. Additionally, even when blocking was disabled, the last field was
3078     blocked for exactly one frame.
3079     Since 3.1.1, due to changes in player movement handling, the last field
3080     is not blocked at all when blocking is disabled. When blocking is enabled,
3081     the last field is blocked for exactly the number of frames of one player
3082     move. Additionally, if the player is Murphy, the hero of Supaplex, the
3083     last field is blocked for exactly one more than the number of frames of
3084     one player move.
3085
3086     Affected levels/tapes:
3087     (!!! yet to be determined -- probably many !!!)
3088   */
3089
3090   game.use_block_last_field_bug =
3091     (game.engine_version < VERSION_IDENT(3,1,1,0));
3092
3093   /* various special flags and settings for native Emerald Mine game engine */
3094
3095   game_em.use_single_button =
3096     (game.engine_version > VERSION_IDENT(4,0,0,2));
3097
3098   game_em.use_snap_key_bug =
3099     (game.engine_version < VERSION_IDENT(4,0,1,0));
3100
3101   game_em.use_random_bug =
3102     (tape.property_bits & TAPE_PROPERTY_EM_RANDOM_BUG);
3103
3104   boolean use_old_em_engine = (game.engine_version < VERSION_IDENT(4,2,0,0));
3105
3106   game_em.use_old_explosions            = use_old_em_engine;
3107   game_em.use_old_android               = use_old_em_engine;
3108   game_em.use_old_push_elements         = use_old_em_engine;
3109   game_em.use_old_push_into_acid        = use_old_em_engine;
3110
3111   game_em.use_wrap_around               = !use_old_em_engine;
3112
3113   // --------------------------------------------------------------------------
3114
3115   // set maximal allowed number of custom element changes per game frame
3116   game.max_num_changes_per_frame = 1;
3117
3118   // default scan direction: scan playfield from top/left to bottom/right
3119   InitPlayfieldScanMode(CA_ARG_SCAN_MODE_NORMAL);
3120
3121   // dynamically adjust element properties according to game engine version
3122   InitElementPropertiesEngine(game.engine_version);
3123
3124   // ---------- initialize special element properties -------------------------
3125
3126   // "EL_AMOEBA_DROPPING" missed property "can fall" in older game versions
3127   if (use_amoeba_dropping_cannot_fall_bug)
3128     SET_PROPERTY(EL_AMOEBA_DROPPING, EP_CAN_FALL, FALSE);
3129
3130   // ---------- initialize player's initial move delay ------------------------
3131
3132   // dynamically adjust player properties according to level information
3133   for (i = 0; i < MAX_PLAYERS; i++)
3134     game.initial_move_delay_value[i] =
3135       get_move_delay_from_stepsize(level.initial_player_stepsize[i]);
3136
3137   // dynamically adjust player properties according to game engine version
3138   for (i = 0; i < MAX_PLAYERS; i++)
3139     game.initial_move_delay[i] =
3140       (game.engine_version <= VERSION_IDENT(2,0,1,0) ?
3141        game.initial_move_delay_value[i] : 0);
3142
3143   // ---------- initialize player's initial push delay ------------------------
3144
3145   // dynamically adjust player properties according to game engine version
3146   game.initial_push_delay_value =
3147     (game.engine_version < VERSION_IDENT(3,0,7,1) ? 5 : -1);
3148
3149   // ---------- initialize changing elements ----------------------------------
3150
3151   // initialize changing elements information
3152   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3153   {
3154     struct ElementInfo *ei = &element_info[i];
3155
3156     // this pointer might have been changed in the level editor
3157     ei->change = &ei->change_page[0];
3158
3159     if (!IS_CUSTOM_ELEMENT(i))
3160     {
3161       ei->change->target_element = EL_EMPTY_SPACE;
3162       ei->change->delay_fixed = 0;
3163       ei->change->delay_random = 0;
3164       ei->change->delay_frames = 1;
3165     }
3166
3167     for (j = 0; j < NUM_CHANGE_EVENTS; j++)
3168     {
3169       ei->has_change_event[j] = FALSE;
3170
3171       ei->event_page_nr[j] = 0;
3172       ei->event_page[j] = &ei->change_page[0];
3173     }
3174   }
3175
3176   // add changing elements from pre-defined list
3177   for (i = 0; change_delay_list[i].element != EL_UNDEFINED; i++)
3178   {
3179     struct ChangingElementInfo *ch_delay = &change_delay_list[i];
3180     struct ElementInfo *ei = &element_info[ch_delay->element];
3181
3182     ei->change->target_element       = ch_delay->target_element;
3183     ei->change->delay_fixed          = ch_delay->change_delay;
3184
3185     ei->change->pre_change_function  = ch_delay->pre_change_function;
3186     ei->change->change_function      = ch_delay->change_function;
3187     ei->change->post_change_function = ch_delay->post_change_function;
3188
3189     ei->change->can_change = TRUE;
3190     ei->change->can_change_or_has_action = TRUE;
3191
3192     ei->has_change_event[CE_DELAY] = TRUE;
3193
3194     SET_PROPERTY(ch_delay->element, EP_CAN_CHANGE, TRUE);
3195     SET_PROPERTY(ch_delay->element, EP_CAN_CHANGE_OR_HAS_ACTION, TRUE);
3196   }
3197
3198   // ---------- initialize internal run-time variables ------------------------
3199
3200   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
3201   {
3202     struct ElementInfo *ei = &element_info[EL_CUSTOM_START + i];
3203
3204     for (j = 0; j < ei->num_change_pages; j++)
3205     {
3206       ei->change_page[j].can_change_or_has_action =
3207         (ei->change_page[j].can_change |
3208          ei->change_page[j].has_action);
3209     }
3210   }
3211
3212   // add change events from custom element configuration
3213   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
3214   {
3215     struct ElementInfo *ei = &element_info[EL_CUSTOM_START + i];
3216
3217     for (j = 0; j < ei->num_change_pages; j++)
3218     {
3219       if (!ei->change_page[j].can_change_or_has_action)
3220         continue;
3221
3222       for (k = 0; k < NUM_CHANGE_EVENTS; k++)
3223       {
3224         // only add event page for the first page found with this event
3225         if (ei->change_page[j].has_event[k] && !(ei->has_change_event[k]))
3226         {
3227           ei->has_change_event[k] = TRUE;
3228
3229           ei->event_page_nr[k] = j;
3230           ei->event_page[k] = &ei->change_page[j];
3231         }
3232       }
3233     }
3234   }
3235
3236   // ---------- initialize reference elements in change conditions ------------
3237
3238   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
3239   {
3240     int element = EL_CUSTOM_START + i;
3241     struct ElementInfo *ei = &element_info[element];
3242
3243     for (j = 0; j < ei->num_change_pages; j++)
3244     {
3245       int trigger_element = ei->change_page[j].initial_trigger_element;
3246
3247       if (trigger_element >= EL_PREV_CE_8 &&
3248           trigger_element <= EL_NEXT_CE_8)
3249         trigger_element = RESOLVED_REFERENCE_ELEMENT(element, trigger_element);
3250
3251       ei->change_page[j].trigger_element = trigger_element;
3252     }
3253   }
3254
3255   // ---------- initialize run-time trigger player and element ----------------
3256
3257   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
3258   {
3259     struct ElementInfo *ei = &element_info[EL_CUSTOM_START + i];
3260
3261     for (j = 0; j < ei->num_change_pages; j++)
3262     {
3263       ei->change_page[j].actual_trigger_element = EL_EMPTY;
3264       ei->change_page[j].actual_trigger_player = EL_EMPTY;
3265       ei->change_page[j].actual_trigger_player_bits = CH_PLAYER_NONE;
3266       ei->change_page[j].actual_trigger_side = CH_SIDE_NONE;
3267       ei->change_page[j].actual_trigger_ce_value = 0;
3268       ei->change_page[j].actual_trigger_ce_score = 0;
3269     }
3270   }
3271
3272   // ---------- initialize trigger events -------------------------------------
3273
3274   // initialize trigger events information
3275   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3276     for (j = 0; j < NUM_CHANGE_EVENTS; j++)
3277       trigger_events[i][j] = FALSE;
3278
3279   // add trigger events from element change event properties
3280   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3281   {
3282     struct ElementInfo *ei = &element_info[i];
3283
3284     for (j = 0; j < ei->num_change_pages; j++)
3285     {
3286       if (!ei->change_page[j].can_change_or_has_action)
3287         continue;
3288
3289       if (ei->change_page[j].has_event[CE_BY_OTHER_ACTION])
3290       {
3291         int trigger_element = ei->change_page[j].trigger_element;
3292
3293         for (k = 0; k < NUM_CHANGE_EVENTS; k++)
3294         {
3295           if (ei->change_page[j].has_event[k])
3296           {
3297             if (IS_GROUP_ELEMENT(trigger_element))
3298             {
3299               struct ElementGroupInfo *group =
3300                 element_info[trigger_element].group;
3301
3302               for (l = 0; l < group->num_elements_resolved; l++)
3303                 trigger_events[group->element_resolved[l]][k] = TRUE;
3304             }
3305             else if (trigger_element == EL_ANY_ELEMENT)
3306               for (l = 0; l < MAX_NUM_ELEMENTS; l++)
3307                 trigger_events[l][k] = TRUE;
3308             else
3309               trigger_events[trigger_element][k] = TRUE;
3310           }
3311         }
3312       }
3313     }
3314   }
3315
3316   // ---------- initialize push delay -----------------------------------------
3317
3318   // initialize push delay values to default
3319   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3320   {
3321     if (!IS_CUSTOM_ELEMENT(i))
3322     {
3323       // set default push delay values (corrected since version 3.0.7-1)
3324       if (game.engine_version < VERSION_IDENT(3,0,7,1))
3325       {
3326         element_info[i].push_delay_fixed = 2;
3327         element_info[i].push_delay_random = 8;
3328       }
3329       else
3330       {
3331         element_info[i].push_delay_fixed = 8;
3332         element_info[i].push_delay_random = 8;
3333       }
3334     }
3335   }
3336
3337   // set push delay value for certain elements from pre-defined list
3338   for (i = 0; push_delay_list[i].element != EL_UNDEFINED; i++)
3339   {
3340     int e = push_delay_list[i].element;
3341
3342     element_info[e].push_delay_fixed  = push_delay_list[i].push_delay_fixed;
3343     element_info[e].push_delay_random = push_delay_list[i].push_delay_random;
3344   }
3345
3346   // set push delay value for Supaplex elements for newer engine versions
3347   if (game.engine_version >= VERSION_IDENT(3,1,0,0))
3348   {
3349     for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3350     {
3351       if (IS_SP_ELEMENT(i))
3352       {
3353         // set SP push delay to just enough to push under a falling zonk
3354         int delay = (game.engine_version >= VERSION_IDENT(3,1,1,0) ? 8 : 6);
3355
3356         element_info[i].push_delay_fixed  = delay;
3357         element_info[i].push_delay_random = 0;
3358       }
3359     }
3360   }
3361
3362   // ---------- initialize move stepsize --------------------------------------
3363
3364   // initialize move stepsize values to default
3365   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3366     if (!IS_CUSTOM_ELEMENT(i))
3367       element_info[i].move_stepsize = MOVE_STEPSIZE_NORMAL;
3368
3369   // set move stepsize value for certain elements from pre-defined list
3370   for (i = 0; move_stepsize_list[i].element != EL_UNDEFINED; i++)
3371   {
3372     int e = move_stepsize_list[i].element;
3373
3374     element_info[e].move_stepsize = move_stepsize_list[i].move_stepsize;
3375
3376     // set move stepsize value for certain elements for older engine versions
3377     if (use_old_move_stepsize_for_magic_wall)
3378     {
3379       if (e == EL_MAGIC_WALL_FILLING ||
3380           e == EL_MAGIC_WALL_EMPTYING ||
3381           e == EL_BD_MAGIC_WALL_FILLING ||
3382           e == EL_BD_MAGIC_WALL_EMPTYING)
3383         element_info[e].move_stepsize *= 2;
3384     }
3385   }
3386
3387   // ---------- initialize collect score --------------------------------------
3388
3389   // initialize collect score values for custom elements from initial value
3390   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3391     if (IS_CUSTOM_ELEMENT(i))
3392       element_info[i].collect_score = element_info[i].collect_score_initial;
3393
3394   // ---------- initialize collect count --------------------------------------
3395
3396   // initialize collect count values for non-custom elements
3397   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3398     if (!IS_CUSTOM_ELEMENT(i))
3399       element_info[i].collect_count_initial = 0;
3400
3401   // add collect count values for all elements from pre-defined list
3402   for (i = 0; collect_count_list[i].element != EL_UNDEFINED; i++)
3403     element_info[collect_count_list[i].element].collect_count_initial =
3404       collect_count_list[i].count;
3405
3406   // ---------- initialize access direction -----------------------------------
3407
3408   // initialize access direction values to default (access from every side)
3409   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3410     if (!IS_CUSTOM_ELEMENT(i))
3411       element_info[i].access_direction = MV_ALL_DIRECTIONS;
3412
3413   // set access direction value for certain elements from pre-defined list
3414   for (i = 0; access_direction_list[i].element != EL_UNDEFINED; i++)
3415     element_info[access_direction_list[i].element].access_direction =
3416       access_direction_list[i].direction;
3417
3418   // ---------- initialize explosion content ----------------------------------
3419   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3420   {
3421     if (IS_CUSTOM_ELEMENT(i))
3422       continue;
3423
3424     for (y = 0; y < 3; y++) for (x = 0; x < 3; x++)
3425     {
3426       // (content for EL_YAMYAM set at run-time with game.yamyam_content_nr)
3427
3428       element_info[i].content.e[x][y] =
3429         (i == EL_PLAYER_1 ? EL_EMERALD_YELLOW :
3430          i == EL_PLAYER_2 ? EL_EMERALD_RED :
3431          i == EL_PLAYER_3 ? EL_EMERALD :
3432          i == EL_PLAYER_4 ? EL_EMERALD_PURPLE :
3433          i == EL_MOLE ? EL_EMERALD_RED :
3434          i == EL_PENGUIN ? EL_EMERALD_PURPLE :
3435          i == EL_BUG ? (x == 1 && y == 1 ? EL_DIAMOND : EL_EMERALD) :
3436          i == EL_BD_BUTTERFLY ? EL_BD_DIAMOND :
3437          i == EL_SP_ELECTRON ? EL_SP_INFOTRON :
3438          i == EL_AMOEBA_TO_DIAMOND ? level.amoeba_content :
3439          i == EL_WALL_EMERALD ? EL_EMERALD :
3440          i == EL_WALL_DIAMOND ? EL_DIAMOND :
3441          i == EL_WALL_BD_DIAMOND ? EL_BD_DIAMOND :
3442          i == EL_WALL_EMERALD_YELLOW ? EL_EMERALD_YELLOW :
3443          i == EL_WALL_EMERALD_RED ? EL_EMERALD_RED :
3444          i == EL_WALL_EMERALD_PURPLE ? EL_EMERALD_PURPLE :
3445          i == EL_WALL_PEARL ? EL_PEARL :
3446          i == EL_WALL_CRYSTAL ? EL_CRYSTAL :
3447          EL_EMPTY);
3448     }
3449   }
3450
3451   // ---------- initialize recursion detection --------------------------------
3452   recursion_loop_depth = 0;
3453   recursion_loop_detected = FALSE;
3454   recursion_loop_element = EL_UNDEFINED;
3455
3456   // ---------- initialize graphics engine ------------------------------------
3457   game.scroll_delay_value =
3458     (game.forced_scroll_delay_value != -1 ? game.forced_scroll_delay_value :
3459      level.game_engine_type == GAME_ENGINE_TYPE_EM &&
3460      !setup.forced_scroll_delay           ? 0 :
3461      setup.scroll_delay                   ? setup.scroll_delay_value       : 0);
3462   game.scroll_delay_value =
3463     MIN(MAX(MIN_SCROLL_DELAY, game.scroll_delay_value), MAX_SCROLL_DELAY);
3464
3465   // ---------- initialize game engine snapshots ------------------------------
3466   for (i = 0; i < MAX_PLAYERS; i++)
3467     game.snapshot.last_action[i] = 0;
3468   game.snapshot.changed_action = FALSE;
3469   game.snapshot.collected_item = FALSE;
3470   game.snapshot.mode =
3471     (strEqual(setup.engine_snapshot_mode, STR_SNAPSHOT_MODE_EVERY_STEP) ?
3472      SNAPSHOT_MODE_EVERY_STEP :
3473      strEqual(setup.engine_snapshot_mode, STR_SNAPSHOT_MODE_EVERY_MOVE) ?
3474      SNAPSHOT_MODE_EVERY_MOVE :
3475      strEqual(setup.engine_snapshot_mode, STR_SNAPSHOT_MODE_EVERY_COLLECT) ?
3476      SNAPSHOT_MODE_EVERY_COLLECT : SNAPSHOT_MODE_OFF);
3477   game.snapshot.save_snapshot = FALSE;
3478
3479   // ---------- initialize level time for Supaplex engine ---------------------
3480   // Supaplex levels with time limit currently unsupported -- should be added
3481   if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
3482     level.time = 0;
3483
3484   // ---------- initialize flags for handling game actions --------------------
3485
3486   // set flags for game actions to default values
3487   game.use_key_actions = TRUE;
3488   game.use_mouse_actions = FALSE;
3489
3490   // when using Mirror Magic game engine, handle mouse events only
3491   if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
3492   {
3493     game.use_key_actions = FALSE;
3494     game.use_mouse_actions = TRUE;
3495   }
3496
3497   // check for custom elements with mouse click events
3498   if (level.game_engine_type == GAME_ENGINE_TYPE_RND)
3499   {
3500     for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
3501     {
3502       int element = EL_CUSTOM_START + i;
3503
3504       if (HAS_CHANGE_EVENT(element, CE_CLICKED_BY_MOUSE) ||
3505           HAS_CHANGE_EVENT(element, CE_PRESSED_BY_MOUSE) ||
3506           HAS_CHANGE_EVENT(element, CE_MOUSE_CLICKED_ON_X) ||
3507           HAS_CHANGE_EVENT(element, CE_MOUSE_PRESSED_ON_X))
3508         game.use_mouse_actions = TRUE;
3509     }
3510   }
3511 }
3512
3513 static int get_num_special_action(int element, int action_first,
3514                                   int action_last)
3515 {
3516   int num_special_action = 0;
3517   int i, j;
3518
3519   for (i = action_first; i <= action_last; i++)
3520   {
3521     boolean found = FALSE;
3522
3523     for (j = 0; j < NUM_DIRECTIONS; j++)
3524       if (el_act_dir2img(element, i, j) !=
3525           el_act_dir2img(element, ACTION_DEFAULT, j))
3526         found = TRUE;
3527
3528     if (found)
3529       num_special_action++;
3530     else
3531       break;
3532   }
3533
3534   return num_special_action;
3535 }
3536
3537
3538 // ============================================================================
3539 // InitGame()
3540 // ----------------------------------------------------------------------------
3541 // initialize and start new game
3542 // ============================================================================
3543
3544 #if DEBUG_INIT_PLAYER
3545 static void DebugPrintPlayerStatus(char *message)
3546 {
3547   int i;
3548
3549   if (!options.debug)
3550     return;
3551
3552   Debug("game:init:player", "%s:", message);
3553
3554   for (i = 0; i < MAX_PLAYERS; i++)
3555   {
3556     struct PlayerInfo *player = &stored_player[i];
3557
3558     Debug("game:init:player",
3559           "- player %d: present == %d, connected == %d [%d/%d], active == %d%s",
3560           i + 1,
3561           player->present,
3562           player->connected,
3563           player->connected_locally,
3564           player->connected_network,
3565           player->active,
3566           (local_player == player ? " (local player)" : ""));
3567   }
3568 }
3569 #endif
3570
3571 void InitGame(void)
3572 {
3573   int full_lev_fieldx = lev_fieldx + (BorderElement != EL_EMPTY ? 2 : 0);
3574   int full_lev_fieldy = lev_fieldy + (BorderElement != EL_EMPTY ? 2 : 0);
3575   int fade_mask = REDRAW_FIELD;
3576   boolean restarting = (game_status == GAME_MODE_PLAYING);
3577   boolean emulate_bd = TRUE;    // unless non-BOULDERDASH elements found
3578   boolean emulate_sp = TRUE;    // unless non-SUPAPLEX    elements found
3579   int initial_move_dir = MV_DOWN;
3580   int i, j, x, y;
3581
3582   // required here to update video display before fading (FIX THIS)
3583   DrawMaskedBorder(REDRAW_DOOR_2);
3584
3585   if (!game.restart_level)
3586     CloseDoor(DOOR_CLOSE_1);
3587
3588   if (restarting)
3589   {
3590     // force fading out global animations displayed during game play
3591     SetGameStatus(GAME_MODE_PSEUDO_RESTARTING);
3592   }
3593   else
3594   {
3595     SetGameStatus(GAME_MODE_PLAYING);
3596   }
3597
3598   if (level_editor_test_game)
3599     FadeSkipNextFadeOut();
3600   else
3601     FadeSetEnterScreen();
3602
3603   if (CheckFadeAll())
3604     fade_mask = REDRAW_ALL;
3605
3606   FadeLevelSoundsAndMusic();
3607
3608   ExpireSoundLoops(TRUE);
3609
3610   FadeOut(fade_mask);
3611
3612   if (restarting)
3613   {
3614     // force restarting global animations displayed during game play
3615     RestartGlobalAnimsByStatus(GAME_MODE_PSEUDO_RESTARTING);
3616
3617     SetGameStatus(GAME_MODE_PLAYING);
3618   }
3619
3620   if (level_editor_test_game)
3621     FadeSkipNextFadeIn();
3622
3623   // needed if different viewport properties defined for playing
3624   ChangeViewportPropertiesIfNeeded();
3625
3626   ClearField();
3627
3628   DrawCompleteVideoDisplay();
3629
3630   OpenDoor(GetDoorState() | DOOR_NO_DELAY | DOOR_FORCE_REDRAW);
3631
3632   InitGameEngine();
3633   InitGameControlValues();
3634
3635   if (tape.recording)
3636   {
3637     // initialize tape actions from game when recording tape
3638     tape.use_key_actions   = game.use_key_actions;
3639     tape.use_mouse_actions = game.use_mouse_actions;
3640
3641     // initialize visible playfield size when recording tape (for team mode)
3642     tape.scr_fieldx = SCR_FIELDX;
3643     tape.scr_fieldy = SCR_FIELDY;
3644   }
3645
3646   // don't play tapes over network
3647   network_playing = (network.enabled && !tape.playing);
3648
3649   for (i = 0; i < MAX_PLAYERS; i++)
3650   {
3651     struct PlayerInfo *player = &stored_player[i];
3652
3653     player->index_nr = i;
3654     player->index_bit = (1 << i);
3655     player->element_nr = EL_PLAYER_1 + i;
3656
3657     player->present = FALSE;
3658     player->active = FALSE;
3659     player->mapped = FALSE;
3660
3661     player->killed = FALSE;
3662     player->reanimated = FALSE;
3663     player->buried = FALSE;
3664
3665     player->action = 0;
3666     player->effective_action = 0;
3667     player->programmed_action = 0;
3668     player->snap_action = 0;
3669
3670     player->mouse_action.lx = 0;
3671     player->mouse_action.ly = 0;
3672     player->mouse_action.button = 0;
3673     player->mouse_action.button_hint = 0;
3674
3675     player->effective_mouse_action.lx = 0;
3676     player->effective_mouse_action.ly = 0;
3677     player->effective_mouse_action.button = 0;
3678     player->effective_mouse_action.button_hint = 0;
3679
3680     for (j = 0; j < MAX_NUM_KEYS; j++)
3681       player->key[j] = FALSE;
3682
3683     player->num_white_keys = 0;
3684
3685     player->dynabomb_count = 0;
3686     player->dynabomb_size = 1;
3687     player->dynabombs_left = 0;
3688     player->dynabomb_xl = FALSE;
3689
3690     player->MovDir = initial_move_dir;
3691     player->MovPos = 0;
3692     player->GfxPos = 0;
3693     player->GfxDir = initial_move_dir;
3694     player->GfxAction = ACTION_DEFAULT;
3695     player->Frame = 0;
3696     player->StepFrame = 0;
3697
3698     player->initial_element = player->element_nr;
3699     player->artwork_element =
3700       (level.use_artwork_element[i] ? level.artwork_element[i] :
3701        player->element_nr);
3702     player->use_murphy = FALSE;
3703
3704     player->block_last_field = FALSE;   // initialized in InitPlayerField()
3705     player->block_delay_adjustment = 0; // initialized in InitPlayerField()
3706
3707     player->gravity = level.initial_player_gravity[i];
3708
3709     player->can_fall_into_acid = CAN_MOVE_INTO_ACID(player->element_nr);
3710
3711     player->actual_frame_counter.count = 0;
3712     player->actual_frame_counter.value = 1;
3713
3714     player->step_counter = 0;
3715
3716     player->last_move_dir = initial_move_dir;
3717
3718     player->is_active = FALSE;
3719
3720     player->is_waiting = FALSE;
3721     player->is_moving = FALSE;
3722     player->is_auto_moving = FALSE;
3723     player->is_digging = FALSE;
3724     player->is_snapping = FALSE;
3725     player->is_collecting = FALSE;
3726     player->is_pushing = FALSE;
3727     player->is_switching = FALSE;
3728     player->is_dropping = FALSE;
3729     player->is_dropping_pressed = FALSE;
3730
3731     player->is_bored = FALSE;
3732     player->is_sleeping = FALSE;
3733
3734     player->was_waiting = TRUE;
3735     player->was_moving = FALSE;
3736     player->was_snapping = FALSE;
3737     player->was_dropping = FALSE;
3738
3739     player->force_dropping = FALSE;
3740
3741     player->frame_counter_bored = -1;
3742     player->frame_counter_sleeping = -1;
3743
3744     player->anim_delay_counter = 0;
3745     player->post_delay_counter = 0;
3746
3747     player->dir_waiting = initial_move_dir;
3748     player->action_waiting = ACTION_DEFAULT;
3749     player->last_action_waiting = ACTION_DEFAULT;
3750     player->special_action_bored = ACTION_DEFAULT;
3751     player->special_action_sleeping = ACTION_DEFAULT;
3752
3753     player->switch_x = -1;
3754     player->switch_y = -1;
3755
3756     player->drop_x = -1;
3757     player->drop_y = -1;
3758
3759     player->show_envelope = 0;
3760
3761     SetPlayerMoveSpeed(player, level.initial_player_stepsize[i], TRUE);
3762
3763     player->push_delay       = -1;      // initialized when pushing starts
3764     player->push_delay_value = game.initial_push_delay_value;
3765
3766     player->drop_delay = 0;
3767     player->drop_pressed_delay = 0;
3768
3769     player->last_jx = -1;
3770     player->last_jy = -1;
3771     player->jx = -1;
3772     player->jy = -1;
3773
3774     player->shield_normal_time_left = 0;
3775     player->shield_deadly_time_left = 0;
3776
3777     player->last_removed_element = EL_UNDEFINED;
3778
3779     player->inventory_infinite_element = EL_UNDEFINED;
3780     player->inventory_size = 0;
3781
3782     if (level.use_initial_inventory[i])
3783     {
3784       for (j = 0; j < level.initial_inventory_size[i]; j++)
3785       {
3786         int element = level.initial_inventory_content[i][j];
3787         int collect_count = element_info[element].collect_count_initial;
3788         int k;
3789
3790         if (!IS_CUSTOM_ELEMENT(element))
3791           collect_count = 1;
3792
3793         if (collect_count == 0)
3794           player->inventory_infinite_element = element;
3795         else
3796           for (k = 0; k < collect_count; k++)
3797             if (player->inventory_size < MAX_INVENTORY_SIZE)
3798               player->inventory_element[player->inventory_size++] = element;
3799       }
3800     }
3801
3802     DigField(player, 0, 0, 0, 0, 0, 0, DF_NO_PUSH);
3803     SnapField(player, 0, 0);
3804
3805     map_player_action[i] = i;
3806   }
3807
3808   network_player_action_received = FALSE;
3809
3810   // initial null action
3811   if (network_playing)
3812     SendToServer_MovePlayer(MV_NONE);
3813
3814   FrameCounter = 0;
3815   TimeFrames = 0;
3816   TimePlayed = 0;
3817   TimeLeft = level.time;
3818   TapeTime = 0;
3819
3820   ScreenMovDir = MV_NONE;
3821   ScreenMovPos = 0;
3822   ScreenGfxPos = 0;
3823
3824   ScrollStepSize = 0;   // will be correctly initialized by ScrollScreen()
3825
3826   game.robot_wheel_x = -1;
3827   game.robot_wheel_y = -1;
3828
3829   game.exit_x = -1;
3830   game.exit_y = -1;
3831
3832   game.all_players_gone = FALSE;
3833
3834   game.LevelSolved = FALSE;
3835   game.GameOver = FALSE;
3836
3837   game.GamePlayed = !tape.playing;
3838
3839   game.LevelSolved_GameWon = FALSE;
3840   game.LevelSolved_GameEnd = FALSE;
3841   game.LevelSolved_SaveTape = FALSE;
3842   game.LevelSolved_SaveScore = FALSE;
3843
3844   game.LevelSolved_CountingTime = 0;
3845   game.LevelSolved_CountingScore = 0;
3846   game.LevelSolved_CountingHealth = 0;
3847
3848   game.panel.active = TRUE;
3849
3850   game.no_level_time_limit = (level.time == 0);
3851   game.time_limit = (leveldir_current->time_limit && setup.time_limit);
3852
3853   game.yamyam_content_nr = 0;
3854   game.robot_wheel_active = FALSE;
3855   game.magic_wall_active = FALSE;
3856   game.magic_wall_time_left = 0;
3857   game.light_time_left = 0;
3858   game.timegate_time_left = 0;
3859   game.switchgate_pos = 0;
3860   game.wind_direction = level.wind_direction_initial;
3861
3862   game.time_final = 0;
3863   game.score_time_final = 0;
3864
3865   game.score = 0;
3866   game.score_final = 0;
3867
3868   game.health = MAX_HEALTH;
3869   game.health_final = MAX_HEALTH;
3870
3871   game.gems_still_needed = level.gems_needed;
3872   game.sokoban_fields_still_needed = 0;
3873   game.sokoban_objects_still_needed = 0;
3874   game.lights_still_needed = 0;
3875   game.players_still_needed = 0;
3876   game.friends_still_needed = 0;
3877
3878   game.lenses_time_left = 0;
3879   game.magnify_time_left = 0;
3880
3881   game.ball_active = level.ball_active_initial;
3882   game.ball_content_nr = 0;
3883
3884   game.explosions_delayed = TRUE;
3885
3886   game.envelope_active = FALSE;
3887
3888   // special case: set custom artwork setting to initial value
3889   game.use_masked_elements = game.use_masked_elements_initial;
3890
3891   for (i = 0; i < NUM_BELTS; i++)
3892   {
3893     game.belt_dir[i] = MV_NONE;
3894     game.belt_dir_nr[i] = 3;            // not moving, next moving left
3895   }
3896
3897   for (i = 0; i < MAX_NUM_AMOEBA; i++)
3898     AmoebaCnt[i] = AmoebaCnt2[i] = 0;
3899
3900 #if DEBUG_INIT_PLAYER
3901   DebugPrintPlayerStatus("Player status at level initialization");
3902 #endif
3903
3904   SCAN_PLAYFIELD(x, y)
3905   {
3906     Tile[x][y] = Last[x][y] = level.field[x][y];
3907     MovPos[x][y] = MovDir[x][y] = MovDelay[x][y] = 0;
3908     ChangeDelay[x][y] = 0;
3909     ChangePage[x][y] = -1;
3910     CustomValue[x][y] = 0;              // initialized in InitField()
3911     Store[x][y] = Store2[x][y] = StorePlayer[x][y] = Back[x][y] = 0;
3912     AmoebaNr[x][y] = 0;
3913     WasJustMoving[x][y] = 0;
3914     WasJustFalling[x][y] = 0;
3915     CheckCollision[x][y] = 0;
3916     CheckImpact[x][y] = 0;
3917     Stop[x][y] = FALSE;
3918     Pushed[x][y] = FALSE;
3919
3920     ChangeCount[x][y] = 0;
3921     ChangeEvent[x][y] = -1;
3922
3923     ExplodePhase[x][y] = 0;
3924     ExplodeDelay[x][y] = 0;
3925     ExplodeField[x][y] = EX_TYPE_NONE;
3926
3927     RunnerVisit[x][y] = 0;
3928     PlayerVisit[x][y] = 0;
3929
3930     GfxFrame[x][y] = 0;
3931     GfxRandom[x][y] = INIT_GFX_RANDOM();
3932     GfxRandomStatic[x][y] = INIT_GFX_RANDOM();
3933     GfxElement[x][y] = EL_UNDEFINED;
3934     GfxElementEmpty[x][y] = EL_EMPTY;
3935     GfxAction[x][y] = ACTION_DEFAULT;
3936     GfxDir[x][y] = MV_NONE;
3937     GfxRedraw[x][y] = GFX_REDRAW_NONE;
3938   }
3939
3940   SCAN_PLAYFIELD(x, y)
3941   {
3942     if (emulate_bd && !IS_BD_ELEMENT(Tile[x][y]))
3943       emulate_bd = FALSE;
3944     if (emulate_sp && !IS_SP_ELEMENT(Tile[x][y]))
3945       emulate_sp = FALSE;
3946
3947     InitField(x, y, TRUE);
3948
3949     ResetGfxAnimation(x, y);
3950   }
3951
3952   InitBeltMovement();
3953
3954   for (i = 0; i < MAX_PLAYERS; i++)
3955   {
3956     struct PlayerInfo *player = &stored_player[i];
3957
3958     // set number of special actions for bored and sleeping animation
3959     player->num_special_action_bored =
3960       get_num_special_action(player->artwork_element,
3961                              ACTION_BORING_1, ACTION_BORING_LAST);
3962     player->num_special_action_sleeping =
3963       get_num_special_action(player->artwork_element,
3964                              ACTION_SLEEPING_1, ACTION_SLEEPING_LAST);
3965   }
3966
3967   game.emulation = (emulate_bd ? EMU_BOULDERDASH :
3968                     emulate_sp ? EMU_SUPAPLEX : EMU_NONE);
3969
3970   // initialize type of slippery elements
3971   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3972   {
3973     if (!IS_CUSTOM_ELEMENT(i))
3974     {
3975       // default: elements slip down either to the left or right randomly
3976       element_info[i].slippery_type = SLIPPERY_ANY_RANDOM;
3977
3978       // SP style elements prefer to slip down on the left side
3979       if (game.engine_version >= VERSION_IDENT(3,1,1,0) && IS_SP_ELEMENT(i))
3980         element_info[i].slippery_type = SLIPPERY_ANY_LEFT_RIGHT;
3981
3982       // BD style elements prefer to slip down on the left side
3983       if (game.emulation == EMU_BOULDERDASH)
3984         element_info[i].slippery_type = SLIPPERY_ANY_LEFT_RIGHT;
3985     }
3986   }
3987
3988   // initialize explosion and ignition delay
3989   for (i = 0; i < MAX_NUM_ELEMENTS; i++)
3990   {
3991     if (!IS_CUSTOM_ELEMENT(i))
3992     {
3993       int num_phase = 8;
3994       int delay = (((IS_SP_ELEMENT(i) && i != EL_EMPTY_SPACE) &&
3995                     game.engine_version >= VERSION_IDENT(3,1,0,0)) ||
3996                    game.emulation == EMU_SUPAPLEX ? 3 : 2);
3997       int last_phase = (num_phase + 1) * delay;
3998       int half_phase = (num_phase / 2) * delay;
3999
4000       element_info[i].explosion_delay = last_phase - 1;
4001       element_info[i].ignition_delay = half_phase;
4002
4003       if (i == EL_BLACK_ORB)
4004         element_info[i].ignition_delay = 1;
4005     }
4006   }
4007
4008   // correct non-moving belts to start moving left
4009   for (i = 0; i < NUM_BELTS; i++)
4010     if (game.belt_dir[i] == MV_NONE)
4011       game.belt_dir_nr[i] = 3;          // not moving, next moving left
4012
4013 #if USE_NEW_PLAYER_ASSIGNMENTS
4014   // use preferred player also in local single-player mode
4015   if (!network.enabled && !game.team_mode)
4016   {
4017     int new_index_nr = setup.network_player_nr;
4018
4019     if (new_index_nr >= 0 && new_index_nr < MAX_PLAYERS)
4020     {
4021       for (i = 0; i < MAX_PLAYERS; i++)
4022         stored_player[i].connected_locally = FALSE;
4023
4024       stored_player[new_index_nr].connected_locally = TRUE;
4025     }
4026   }
4027
4028   for (i = 0; i < MAX_PLAYERS; i++)
4029   {
4030     stored_player[i].connected = FALSE;
4031
4032     // in network game mode, the local player might not be the first player
4033     if (stored_player[i].connected_locally)
4034       local_player = &stored_player[i];
4035   }
4036
4037   if (!network.enabled)
4038     local_player->connected = TRUE;
4039
4040   if (tape.playing)
4041   {
4042     for (i = 0; i < MAX_PLAYERS; i++)
4043       stored_player[i].connected = tape.player_participates[i];
4044   }
4045   else if (network.enabled)
4046   {
4047     // add team mode players connected over the network (needed for correct
4048     // assignment of player figures from level to locally playing players)
4049
4050     for (i = 0; i < MAX_PLAYERS; i++)
4051       if (stored_player[i].connected_network)
4052         stored_player[i].connected = TRUE;
4053   }
4054   else if (game.team_mode)
4055   {
4056     // try to guess locally connected team mode players (needed for correct
4057     // assignment of player figures from level to locally playing players)
4058
4059     for (i = 0; i < MAX_PLAYERS; i++)
4060       if (setup.input[i].use_joystick ||
4061           setup.input[i].key.left != KSYM_UNDEFINED)
4062         stored_player[i].connected = TRUE;
4063   }
4064
4065 #if DEBUG_INIT_PLAYER
4066   DebugPrintPlayerStatus("Player status after level initialization");
4067 #endif
4068
4069 #if DEBUG_INIT_PLAYER
4070   Debug("game:init:player", "Reassigning players ...");
4071 #endif
4072
4073   // check if any connected player was not found in playfield
4074   for (i = 0; i < MAX_PLAYERS; i++)
4075   {
4076     struct PlayerInfo *player = &stored_player[i];
4077
4078     if (player->connected && !player->present)
4079     {
4080       struct PlayerInfo *field_player = NULL;
4081
4082 #if DEBUG_INIT_PLAYER
4083       Debug("game:init:player",
4084             "- looking for field player for player %d ...", i + 1);
4085 #endif
4086
4087       // assign first free player found that is present in the playfield
4088
4089       // first try: look for unmapped playfield player that is not connected
4090       for (j = 0; j < MAX_PLAYERS; j++)
4091         if (field_player == NULL &&
4092             stored_player[j].present &&
4093             !stored_player[j].mapped &&
4094             !stored_player[j].connected)
4095           field_player = &stored_player[j];
4096
4097       // second try: look for *any* unmapped playfield player
4098       for (j = 0; j < MAX_PLAYERS; j++)
4099         if (field_player == NULL &&
4100             stored_player[j].present &&
4101             !stored_player[j].mapped)
4102           field_player = &stored_player[j];
4103
4104       if (field_player != NULL)
4105       {
4106         int jx = field_player->jx, jy = field_player->jy;
4107
4108 #if DEBUG_INIT_PLAYER
4109         Debug("game:init:player", "- found player %d",
4110               field_player->index_nr + 1);
4111 #endif
4112
4113         player->present = FALSE;
4114         player->active = FALSE;
4115
4116         field_player->present = TRUE;
4117         field_player->active = TRUE;
4118
4119         /*
4120         player->initial_element = field_player->initial_element;
4121         player->artwork_element = field_player->artwork_element;
4122
4123         player->block_last_field       = field_player->block_last_field;
4124         player->block_delay_adjustment = field_player->block_delay_adjustment;
4125         */
4126
4127         StorePlayer[jx][jy] = field_player->element_nr;
4128
4129         field_player->jx = field_player->last_jx = jx;
4130         field_player->jy = field_player->last_jy = jy;
4131
4132         if (local_player == player)
4133           local_player = field_player;
4134
4135         map_player_action[field_player->index_nr] = i;
4136
4137         field_player->mapped = TRUE;
4138
4139 #if DEBUG_INIT_PLAYER
4140         Debug("game:init:player", "- map_player_action[%d] == %d",
4141               field_player->index_nr + 1, i + 1);
4142 #endif
4143       }
4144     }
4145
4146     if (player->connected && player->present)
4147       player->mapped = TRUE;
4148   }
4149
4150 #if DEBUG_INIT_PLAYER
4151   DebugPrintPlayerStatus("Player status after player assignment (first stage)");
4152 #endif
4153
4154 #else
4155
4156   // check if any connected player was not found in playfield
4157   for (i = 0; i < MAX_PLAYERS; i++)
4158   {
4159     struct PlayerInfo *player = &stored_player[i];
4160
4161     if (player->connected && !player->present)
4162     {
4163       for (j = 0; j < MAX_PLAYERS; j++)
4164       {
4165         struct PlayerInfo *field_player = &stored_player[j];
4166         int jx = field_player->jx, jy = field_player->jy;
4167
4168         // assign first free player found that is present in the playfield
4169         if (field_player->present && !field_player->connected)
4170         {
4171           player->present = TRUE;
4172           player->active = TRUE;
4173
4174           field_player->present = FALSE;
4175           field_player->active = FALSE;
4176
4177           player->initial_element = field_player->initial_element;
4178           player->artwork_element = field_player->artwork_element;
4179
4180           player->block_last_field       = field_player->block_last_field;
4181           player->block_delay_adjustment = field_player->block_delay_adjustment;
4182
4183           StorePlayer[jx][jy] = player->element_nr;
4184
4185           player->jx = player->last_jx = jx;
4186           player->jy = player->last_jy = jy;
4187
4188           break;
4189         }
4190       }
4191     }
4192   }
4193 #endif
4194
4195 #if 0
4196   Debug("game:init:player", "local_player->present == %d",
4197         local_player->present);
4198 #endif
4199
4200   // set focus to local player for network games, else to all players
4201   game.centered_player_nr = (network_playing ? local_player->index_nr : -1);
4202   game.centered_player_nr_next = game.centered_player_nr;
4203   game.set_centered_player = FALSE;
4204   game.set_centered_player_wrap = FALSE;
4205
4206   if (network_playing && tape.recording)
4207   {
4208     // store client dependent player focus when recording network games
4209     tape.centered_player_nr_next = game.centered_player_nr_next;
4210     tape.set_centered_player = TRUE;
4211   }
4212
4213   if (tape.playing)
4214   {
4215     // when playing a tape, eliminate all players who do not participate
4216
4217 #if USE_NEW_PLAYER_ASSIGNMENTS
4218
4219     if (!game.team_mode)
4220     {
4221       for (i = 0; i < MAX_PLAYERS; i++)
4222       {
4223         if (stored_player[i].active &&
4224             !tape.player_participates[map_player_action[i]])
4225         {
4226           struct PlayerInfo *player = &stored_player[i];
4227           int jx = player->jx, jy = player->jy;
4228
4229 #if DEBUG_INIT_PLAYER
4230           Debug("game:init:player", "Removing player %d at (%d, %d)",
4231                 i + 1, jx, jy);
4232 #endif
4233
4234           player->active = FALSE;
4235           StorePlayer[jx][jy] = 0;
4236           Tile[jx][jy] = EL_EMPTY;
4237         }
4238       }
4239     }
4240
4241 #else
4242
4243     for (i = 0; i < MAX_PLAYERS; i++)
4244     {
4245       if (stored_player[i].active &&
4246           !tape.player_participates[i])
4247       {
4248         struct PlayerInfo *player = &stored_player[i];
4249         int jx = player->jx, jy = player->jy;
4250
4251         player->active = FALSE;
4252         StorePlayer[jx][jy] = 0;
4253         Tile[jx][jy] = EL_EMPTY;
4254       }
4255     }
4256 #endif
4257   }
4258   else if (!network.enabled && !game.team_mode)         // && !tape.playing
4259   {
4260     // when in single player mode, eliminate all but the local player
4261
4262     for (i = 0; i < MAX_PLAYERS; i++)
4263     {
4264       struct PlayerInfo *player = &stored_player[i];
4265
4266       if (player->active && player != local_player)
4267       {
4268         int jx = player->jx, jy = player->jy;
4269
4270         player->active = FALSE;
4271         player->present = FALSE;
4272
4273         StorePlayer[jx][jy] = 0;
4274         Tile[jx][jy] = EL_EMPTY;
4275       }
4276     }
4277   }
4278
4279   for (i = 0; i < MAX_PLAYERS; i++)
4280     if (stored_player[i].active)
4281       game.players_still_needed++;
4282
4283   if (level.solved_by_one_player)
4284     game.players_still_needed = 1;
4285
4286   // when recording the game, store which players take part in the game
4287   if (tape.recording)
4288   {
4289 #if USE_NEW_PLAYER_ASSIGNMENTS
4290     for (i = 0; i < MAX_PLAYERS; i++)
4291       if (stored_player[i].connected)
4292         tape.player_participates[i] = TRUE;
4293 #else
4294     for (i = 0; i < MAX_PLAYERS; i++)
4295       if (stored_player[i].active)
4296         tape.player_participates[i] = TRUE;
4297 #endif
4298   }
4299
4300 #if DEBUG_INIT_PLAYER
4301   DebugPrintPlayerStatus("Player status after player assignment (final stage)");
4302 #endif
4303
4304   if (BorderElement == EL_EMPTY)
4305   {
4306     SBX_Left = 0;
4307     SBX_Right = lev_fieldx - SCR_FIELDX;
4308     SBY_Upper = 0;
4309     SBY_Lower = lev_fieldy - SCR_FIELDY;
4310   }
4311   else
4312   {
4313     SBX_Left = -1;
4314     SBX_Right = lev_fieldx - SCR_FIELDX + 1;
4315     SBY_Upper = -1;
4316     SBY_Lower = lev_fieldy - SCR_FIELDY + 1;
4317   }
4318
4319   if (full_lev_fieldx <= SCR_FIELDX)
4320     SBX_Left = SBX_Right = -1 * (SCR_FIELDX - lev_fieldx) / 2;
4321   if (full_lev_fieldy <= SCR_FIELDY)
4322     SBY_Upper = SBY_Lower = -1 * (SCR_FIELDY - lev_fieldy) / 2;
4323
4324   if (EVEN(SCR_FIELDX) && full_lev_fieldx > SCR_FIELDX)
4325     SBX_Left--;
4326   if (EVEN(SCR_FIELDY) && full_lev_fieldy > SCR_FIELDY)
4327     SBY_Upper--;
4328
4329   // if local player not found, look for custom element that might create
4330   // the player (make some assumptions about the right custom element)
4331   if (!local_player->present)
4332   {
4333     int start_x = 0, start_y = 0;
4334     int found_rating = 0;
4335     int found_element = EL_UNDEFINED;
4336     int player_nr = local_player->index_nr;
4337
4338     SCAN_PLAYFIELD(x, y)
4339     {
4340       int element = Tile[x][y];
4341       int content;
4342       int xx, yy;
4343       boolean is_player;
4344
4345       if (level.use_start_element[player_nr] &&
4346           level.start_element[player_nr] == element &&
4347           found_rating < 4)
4348       {
4349         start_x = x;
4350         start_y = y;
4351
4352         found_rating = 4;
4353         found_element = element;
4354       }
4355
4356       if (!IS_CUSTOM_ELEMENT(element))
4357         continue;
4358
4359       if (CAN_CHANGE(element))
4360       {
4361         for (i = 0; i < element_info[element].num_change_pages; i++)
4362         {
4363           // check for player created from custom element as single target
4364           content = element_info[element].change_page[i].target_element;
4365           is_player = IS_PLAYER_ELEMENT(content);
4366
4367           if (is_player && (found_rating < 3 ||
4368                             (found_rating == 3 && element < found_element)))
4369           {
4370             start_x = x;
4371             start_y = y;
4372
4373             found_rating = 3;
4374             found_element = element;
4375           }
4376         }
4377       }
4378
4379       for (yy = 0; yy < 3; yy++) for (xx = 0; xx < 3; xx++)
4380       {
4381         // check for player created from custom element as explosion content
4382         content = element_info[element].content.e[xx][yy];
4383         is_player = IS_PLAYER_ELEMENT(content);
4384
4385         if (is_player && (found_rating < 2 ||
4386                           (found_rating == 2 && element < found_element)))
4387         {
4388           start_x = x + xx - 1;
4389           start_y = y + yy - 1;
4390
4391           found_rating = 2;
4392           found_element = element;
4393         }
4394
4395         if (!CAN_CHANGE(element))
4396           continue;
4397
4398         for (i = 0; i < element_info[element].num_change_pages; i++)
4399         {
4400           // check for player created from custom element as extended target
4401           content =
4402             element_info[element].change_page[i].target_content.e[xx][yy];
4403
4404           is_player = IS_PLAYER_ELEMENT(content);
4405
4406           if (is_player && (found_rating < 1 ||
4407                             (found_rating == 1 && element < found_element)))
4408           {
4409             start_x = x + xx - 1;
4410             start_y = y + yy - 1;
4411
4412             found_rating = 1;
4413             found_element = element;
4414           }
4415         }
4416       }
4417     }
4418
4419     scroll_x = SCROLL_POSITION_X(start_x);
4420     scroll_y = SCROLL_POSITION_Y(start_y);
4421   }
4422   else
4423   {
4424     scroll_x = SCROLL_POSITION_X(local_player->jx);
4425     scroll_y = SCROLL_POSITION_Y(local_player->jy);
4426   }
4427
4428   // !!! FIX THIS (START) !!!
4429   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
4430   {
4431     InitGameEngine_EM();
4432   }
4433   else if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
4434   {
4435     InitGameEngine_SP();
4436   }
4437   else if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
4438   {
4439     InitGameEngine_MM();
4440   }
4441   else
4442   {
4443     DrawLevel(REDRAW_FIELD);
4444     DrawAllPlayers();
4445
4446     // after drawing the level, correct some elements
4447     if (game.timegate_time_left == 0)
4448       CloseAllOpenTimegates();
4449   }
4450
4451   // blit playfield from scroll buffer to normal back buffer for fading in
4452   BlitScreenToBitmap(backbuffer);
4453   // !!! FIX THIS (END) !!!
4454
4455   DrawMaskedBorder(fade_mask);
4456
4457   FadeIn(fade_mask);
4458
4459 #if 1
4460   // full screen redraw is required at this point in the following cases:
4461   // - special editor door undrawn when game was started from level editor
4462   // - drawing area (playfield) was changed and has to be removed completely
4463   redraw_mask = REDRAW_ALL;
4464   BackToFront();
4465 #endif
4466
4467   if (!game.restart_level)
4468   {
4469     // copy default game door content to main double buffer
4470
4471     // !!! CHECK AGAIN !!!
4472     SetPanelBackground();
4473     // SetDoorBackgroundImage(IMG_BACKGROUND_PANEL);
4474     DrawBackground(DX, DY, DXSIZE, DYSIZE);
4475   }
4476
4477   SetPanelBackground();
4478   SetDrawBackgroundMask(REDRAW_DOOR_1);
4479
4480   UpdateAndDisplayGameControlValues();
4481
4482   if (!game.restart_level)
4483   {
4484     UnmapGameButtons();
4485     UnmapTapeButtons();
4486
4487     FreeGameButtons();
4488     CreateGameButtons();
4489
4490     MapGameButtons();
4491     MapTapeButtons();
4492
4493     // copy actual game door content to door double buffer for OpenDoor()
4494     BlitBitmap(drawto, bitmap_db_door_1, DX, DY, DXSIZE, DYSIZE, 0, 0);
4495
4496     OpenDoor(DOOR_OPEN_ALL);
4497
4498     KeyboardAutoRepeatOffUnlessAutoplay();
4499
4500 #if DEBUG_INIT_PLAYER
4501     DebugPrintPlayerStatus("Player status (final)");
4502 #endif
4503   }
4504
4505   UnmapAllGadgets();
4506
4507   MapGameButtons();
4508   MapTapeButtons();
4509
4510   if (!game.restart_level && !tape.playing)
4511   {
4512     LevelStats_incPlayed(level_nr);
4513
4514     SaveLevelSetup_SeriesInfo();
4515   }
4516
4517   game.restart_level = FALSE;
4518
4519   game.request_active = FALSE;
4520   game.request_active_or_moving = FALSE;
4521
4522   if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
4523     InitGameActions_MM();
4524
4525   SaveEngineSnapshotToListInitial();
4526
4527   if (!game.restart_level)
4528   {
4529     PlaySound(SND_GAME_STARTING);
4530
4531     if (setup.sound_music)
4532       PlayLevelMusic();
4533   }
4534
4535   SetPlayfieldMouseCursorEnabled(!game.use_mouse_actions);
4536 }
4537
4538 void UpdateEngineValues(int actual_scroll_x, int actual_scroll_y,
4539                         int actual_player_x, int actual_player_y)
4540 {
4541   // this is used for non-R'n'D game engines to update certain engine values
4542
4543   // needed to determine if sounds are played within the visible screen area
4544   scroll_x = actual_scroll_x;
4545   scroll_y = actual_scroll_y;
4546
4547   // needed to get player position for "follow finger" playing input method
4548   local_player->jx = actual_player_x;
4549   local_player->jy = actual_player_y;
4550 }
4551
4552 void InitMovDir(int x, int y)
4553 {
4554   int i, element = Tile[x][y];
4555   static int xy[4][2] =
4556   {
4557     {  0, +1 },
4558     { +1,  0 },
4559     {  0, -1 },
4560     { -1,  0 }
4561   };
4562   static int direction[3][4] =
4563   {
4564     { MV_RIGHT, MV_UP,   MV_LEFT,  MV_DOWN },
4565     { MV_LEFT,  MV_DOWN, MV_RIGHT, MV_UP },
4566     { MV_LEFT,  MV_RIGHT, MV_UP, MV_DOWN }
4567   };
4568
4569   switch (element)
4570   {
4571     case EL_BUG_RIGHT:
4572     case EL_BUG_UP:
4573     case EL_BUG_LEFT:
4574     case EL_BUG_DOWN:
4575       Tile[x][y] = EL_BUG;
4576       MovDir[x][y] = direction[0][element - EL_BUG_RIGHT];
4577       break;
4578
4579     case EL_SPACESHIP_RIGHT:
4580     case EL_SPACESHIP_UP:
4581     case EL_SPACESHIP_LEFT:
4582     case EL_SPACESHIP_DOWN:
4583       Tile[x][y] = EL_SPACESHIP;
4584       MovDir[x][y] = direction[0][element - EL_SPACESHIP_RIGHT];
4585       break;
4586
4587     case EL_BD_BUTTERFLY_RIGHT:
4588     case EL_BD_BUTTERFLY_UP:
4589     case EL_BD_BUTTERFLY_LEFT:
4590     case EL_BD_BUTTERFLY_DOWN:
4591       Tile[x][y] = EL_BD_BUTTERFLY;
4592       MovDir[x][y] = direction[0][element - EL_BD_BUTTERFLY_RIGHT];
4593       break;
4594
4595     case EL_BD_FIREFLY_RIGHT:
4596     case EL_BD_FIREFLY_UP:
4597     case EL_BD_FIREFLY_LEFT:
4598     case EL_BD_FIREFLY_DOWN:
4599       Tile[x][y] = EL_BD_FIREFLY;
4600       MovDir[x][y] = direction[0][element - EL_BD_FIREFLY_RIGHT];
4601       break;
4602
4603     case EL_PACMAN_RIGHT:
4604     case EL_PACMAN_UP:
4605     case EL_PACMAN_LEFT:
4606     case EL_PACMAN_DOWN:
4607       Tile[x][y] = EL_PACMAN;
4608       MovDir[x][y] = direction[0][element - EL_PACMAN_RIGHT];
4609       break;
4610
4611     case EL_YAMYAM_LEFT:
4612     case EL_YAMYAM_RIGHT:
4613     case EL_YAMYAM_UP:
4614     case EL_YAMYAM_DOWN:
4615       Tile[x][y] = EL_YAMYAM;
4616       MovDir[x][y] = direction[2][element - EL_YAMYAM_LEFT];
4617       break;
4618
4619     case EL_SP_SNIKSNAK:
4620       MovDir[x][y] = MV_UP;
4621       break;
4622
4623     case EL_SP_ELECTRON:
4624       MovDir[x][y] = MV_LEFT;
4625       break;
4626
4627     case EL_MOLE_LEFT:
4628     case EL_MOLE_RIGHT:
4629     case EL_MOLE_UP:
4630     case EL_MOLE_DOWN:
4631       Tile[x][y] = EL_MOLE;
4632       MovDir[x][y] = direction[2][element - EL_MOLE_LEFT];
4633       break;
4634
4635     case EL_SPRING_LEFT:
4636     case EL_SPRING_RIGHT:
4637       Tile[x][y] = EL_SPRING;
4638       MovDir[x][y] = direction[2][element - EL_SPRING_LEFT];
4639       break;
4640
4641     default:
4642       if (IS_CUSTOM_ELEMENT(element))
4643       {
4644         struct ElementInfo *ei = &element_info[element];
4645         int move_direction_initial = ei->move_direction_initial;
4646         int move_pattern = ei->move_pattern;
4647
4648         if (move_direction_initial == MV_START_PREVIOUS)
4649         {
4650           if (MovDir[x][y] != MV_NONE)
4651             return;
4652
4653           move_direction_initial = MV_START_AUTOMATIC;
4654         }
4655
4656         if (move_direction_initial == MV_START_RANDOM)
4657           MovDir[x][y] = 1 << RND(4);
4658         else if (move_direction_initial & MV_ANY_DIRECTION)
4659           MovDir[x][y] = move_direction_initial;
4660         else if (move_pattern == MV_ALL_DIRECTIONS ||
4661                  move_pattern == MV_TURNING_LEFT ||
4662                  move_pattern == MV_TURNING_RIGHT ||
4663                  move_pattern == MV_TURNING_LEFT_RIGHT ||
4664                  move_pattern == MV_TURNING_RIGHT_LEFT ||
4665                  move_pattern == MV_TURNING_RANDOM)
4666           MovDir[x][y] = 1 << RND(4);
4667         else if (move_pattern == MV_HORIZONTAL)
4668           MovDir[x][y] = (RND(2) ? MV_LEFT : MV_RIGHT);
4669         else if (move_pattern == MV_VERTICAL)
4670           MovDir[x][y] = (RND(2) ? MV_UP : MV_DOWN);
4671         else if (move_pattern & MV_ANY_DIRECTION)
4672           MovDir[x][y] = element_info[element].move_pattern;
4673         else if (move_pattern == MV_ALONG_LEFT_SIDE ||
4674                  move_pattern == MV_ALONG_RIGHT_SIDE)
4675         {
4676           // use random direction as default start direction
4677           if (game.engine_version >= VERSION_IDENT(3,1,0,0))
4678             MovDir[x][y] = 1 << RND(4);
4679
4680           for (i = 0; i < NUM_DIRECTIONS; i++)
4681           {
4682             int x1 = x + xy[i][0];
4683             int y1 = y + xy[i][1];
4684
4685             if (!IN_LEV_FIELD(x1, y1) || !IS_FREE(x1, y1))
4686             {
4687               if (move_pattern == MV_ALONG_RIGHT_SIDE)
4688                 MovDir[x][y] = direction[0][i];
4689               else
4690                 MovDir[x][y] = direction[1][i];
4691
4692               break;
4693             }
4694           }
4695         }
4696       }
4697       else
4698       {
4699         MovDir[x][y] = 1 << RND(4);
4700
4701         if (element != EL_BUG &&
4702             element != EL_SPACESHIP &&
4703             element != EL_BD_BUTTERFLY &&
4704             element != EL_BD_FIREFLY)
4705           break;
4706
4707         for (i = 0; i < NUM_DIRECTIONS; i++)
4708         {
4709           int x1 = x + xy[i][0];
4710           int y1 = y + xy[i][1];
4711
4712           if (!IN_LEV_FIELD(x1, y1) || !IS_FREE(x1, y1))
4713           {
4714             if (element == EL_BUG || element == EL_BD_BUTTERFLY)
4715             {
4716               MovDir[x][y] = direction[0][i];
4717               break;
4718             }
4719             else if (element == EL_SPACESHIP || element == EL_BD_FIREFLY ||
4720                      element == EL_SP_SNIKSNAK || element == EL_SP_ELECTRON)
4721             {
4722               MovDir[x][y] = direction[1][i];
4723               break;
4724             }
4725           }
4726         }
4727       }
4728       break;
4729   }
4730
4731   GfxDir[x][y] = MovDir[x][y];
4732 }
4733
4734 void InitAmoebaNr(int x, int y)
4735 {
4736   int i;
4737   int group_nr = AmoebaNeighbourNr(x, y);
4738
4739   if (group_nr == 0)
4740   {
4741     for (i = 1; i < MAX_NUM_AMOEBA; i++)
4742     {
4743       if (AmoebaCnt[i] == 0)
4744       {
4745         group_nr = i;
4746         break;
4747       }
4748     }
4749   }
4750
4751   AmoebaNr[x][y] = group_nr;
4752   AmoebaCnt[group_nr]++;
4753   AmoebaCnt2[group_nr]++;
4754 }
4755
4756 static void LevelSolved_SetFinalGameValues(void)
4757 {
4758   game.time_final = (game.no_level_time_limit ? TimePlayed : TimeLeft);
4759   game.score_time_final = (level.use_step_counter ? TimePlayed :
4760                            TimePlayed * FRAMES_PER_SECOND + TimeFrames);
4761
4762   game.score_final = (level.game_engine_type == GAME_ENGINE_TYPE_EM ?
4763                       game_em.lev->score :
4764                       level.game_engine_type == GAME_ENGINE_TYPE_MM ?
4765                       game_mm.score :
4766                       game.score);
4767
4768   game.health_final = (level.game_engine_type == GAME_ENGINE_TYPE_MM ?
4769                        MM_HEALTH(game_mm.laser_overload_value) :
4770                        game.health);
4771
4772   game.LevelSolved_CountingTime = game.time_final;
4773   game.LevelSolved_CountingScore = game.score_final;
4774   game.LevelSolved_CountingHealth = game.health_final;
4775 }
4776
4777 static void LevelSolved_DisplayFinalGameValues(int time, int score, int health)
4778 {
4779   game.LevelSolved_CountingTime = time;
4780   game.LevelSolved_CountingScore = score;
4781   game.LevelSolved_CountingHealth = health;
4782
4783   game_panel_controls[GAME_PANEL_TIME].value = time;
4784   game_panel_controls[GAME_PANEL_SCORE].value = score;
4785   game_panel_controls[GAME_PANEL_HEALTH].value = health;
4786
4787   DisplayGameControlValues();
4788 }
4789
4790 static void LevelSolved(void)
4791 {
4792   if (level.game_engine_type == GAME_ENGINE_TYPE_RND &&
4793       game.players_still_needed > 0)
4794     return;
4795
4796   game.LevelSolved = TRUE;
4797   game.GameOver = TRUE;
4798
4799   tape.solved = TRUE;
4800
4801   // needed here to display correct panel values while player walks into exit
4802   LevelSolved_SetFinalGameValues();
4803 }
4804
4805 void GameWon(void)
4806 {
4807   static int time_count_steps;
4808   static int time, time_final;
4809   static float score, score_final; // needed for time score < 10 for 10 seconds
4810   static int health, health_final;
4811   static int game_over_delay_1 = 0;
4812   static int game_over_delay_2 = 0;
4813   static int game_over_delay_3 = 0;
4814   int time_score_base = MIN(MAX(1, level.time_score_base), 10);
4815   float time_score = (float)level.score[SC_TIME_BONUS] / time_score_base;
4816
4817   if (!game.LevelSolved_GameWon)
4818   {
4819     int i;
4820
4821     // do not start end game actions before the player stops moving (to exit)
4822     if (local_player->active && local_player->MovPos)
4823       return;
4824
4825     // calculate final game values after player finished walking into exit
4826     LevelSolved_SetFinalGameValues();
4827
4828     game.LevelSolved_GameWon = TRUE;
4829     game.LevelSolved_SaveTape = tape.recording;
4830     game.LevelSolved_SaveScore = !tape.playing;
4831
4832     if (!tape.playing)
4833     {
4834       LevelStats_incSolved(level_nr);
4835
4836       SaveLevelSetup_SeriesInfo();
4837     }
4838
4839     if (tape.auto_play)         // tape might already be stopped here
4840       tape.auto_play_level_solved = TRUE;
4841
4842     TapeStop();
4843
4844     game_over_delay_1 = FRAMES_PER_SECOND;      // delay before counting time
4845     game_over_delay_2 = FRAMES_PER_SECOND / 2;  // delay before counting health
4846     game_over_delay_3 = FRAMES_PER_SECOND;      // delay before ending the game
4847
4848     time = time_final = game.time_final;
4849     score = score_final = game.score_final;
4850     health = health_final = game.health_final;
4851
4852     // update game panel values before (delayed) counting of score (if any)
4853     LevelSolved_DisplayFinalGameValues(time, score, health);
4854
4855     // if level has time score defined, calculate new final game values
4856     if (time_score > 0)
4857     {
4858       int time_final_max = 999;
4859       int time_frames_final_max = time_final_max * FRAMES_PER_SECOND;
4860       int time_frames = 0;
4861       int time_frames_left = TimeLeft * FRAMES_PER_SECOND - TimeFrames;
4862       int time_frames_played = TimePlayed * FRAMES_PER_SECOND + TimeFrames;
4863
4864       if (TimeLeft > 0)
4865       {
4866         time_final = 0;
4867         time_frames = time_frames_left;
4868       }
4869       else if (game.no_level_time_limit && TimePlayed < time_final_max)
4870       {
4871         time_final = time_final_max;
4872         time_frames = time_frames_final_max - time_frames_played;
4873       }
4874
4875       score_final += time_score * time_frames / FRAMES_PER_SECOND + 0.5;
4876
4877       time_count_steps = MAX(1, ABS(time_final - time) / 100);
4878
4879       if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
4880       {
4881         health_final = 0;
4882         score_final += health * time_score;
4883       }
4884
4885       game.score_final = score_final;
4886       game.health_final = health_final;
4887     }
4888
4889     // if not counting score after game, immediately update game panel values
4890     if (level_editor_test_game || !setup.count_score_after_game)
4891     {
4892       time = time_final;
4893       score = score_final;
4894
4895       LevelSolved_DisplayFinalGameValues(time, score, health);
4896     }
4897
4898     if (level.game_engine_type == GAME_ENGINE_TYPE_RND)
4899     {
4900       // check if last player has left the level
4901       if (game.exit_x >= 0 &&
4902           game.exit_y >= 0)
4903       {
4904         int x = game.exit_x;
4905         int y = game.exit_y;
4906         int element = Tile[x][y];
4907
4908         // close exit door after last player
4909         if ((game.all_players_gone &&
4910              (element == EL_EXIT_OPEN ||
4911               element == EL_SP_EXIT_OPEN ||
4912               element == EL_STEEL_EXIT_OPEN)) ||
4913             element == EL_EM_EXIT_OPEN ||
4914             element == EL_EM_STEEL_EXIT_OPEN)
4915         {
4916
4917           Tile[x][y] =
4918             (element == EL_EXIT_OPEN            ? EL_EXIT_CLOSING :
4919              element == EL_EM_EXIT_OPEN         ? EL_EM_EXIT_CLOSING :
4920              element == EL_SP_EXIT_OPEN         ? EL_SP_EXIT_CLOSING:
4921              element == EL_STEEL_EXIT_OPEN      ? EL_STEEL_EXIT_CLOSING:
4922              EL_EM_STEEL_EXIT_CLOSING);
4923
4924           PlayLevelSoundElementAction(x, y, element, ACTION_CLOSING);
4925         }
4926
4927         // player disappears
4928         DrawLevelField(x, y);
4929       }
4930
4931       for (i = 0; i < MAX_PLAYERS; i++)
4932       {
4933         struct PlayerInfo *player = &stored_player[i];
4934
4935         if (player->present)
4936         {
4937           RemovePlayer(player);
4938
4939           // player disappears
4940           DrawLevelField(player->jx, player->jy);
4941         }
4942       }
4943     }
4944
4945     PlaySound(SND_GAME_WINNING);
4946   }
4947
4948   if (setup.count_score_after_game)
4949   {
4950     if (time != time_final)
4951     {
4952       if (game_over_delay_1 > 0)
4953       {
4954         game_over_delay_1--;
4955
4956         return;
4957       }
4958
4959       int time_to_go = ABS(time_final - time);
4960       int time_count_dir = (time < time_final ? +1 : -1);
4961
4962       if (time_to_go < time_count_steps)
4963         time_count_steps = 1;
4964
4965       time  += time_count_steps * time_count_dir;
4966       score += time_count_steps * time_score;
4967
4968       // set final score to correct rounding differences after counting score
4969       if (time == time_final)
4970         score = score_final;
4971
4972       LevelSolved_DisplayFinalGameValues(time, score, health);
4973
4974       if (time == time_final)
4975         StopSound(SND_GAME_LEVELTIME_BONUS);
4976       else if (setup.sound_loops)
4977         PlaySoundLoop(SND_GAME_LEVELTIME_BONUS);
4978       else
4979         PlaySound(SND_GAME_LEVELTIME_BONUS);
4980
4981       return;
4982     }
4983
4984     if (health != health_final)
4985     {
4986       if (game_over_delay_2 > 0)
4987       {
4988         game_over_delay_2--;
4989
4990         return;
4991       }
4992
4993       int health_count_dir = (health < health_final ? +1 : -1);
4994
4995       health += health_count_dir;
4996       score  += time_score;
4997
4998       LevelSolved_DisplayFinalGameValues(time, score, health);
4999
5000       if (health == health_final)
5001         StopSound(SND_GAME_LEVELTIME_BONUS);
5002       else if (setup.sound_loops)
5003         PlaySoundLoop(SND_GAME_LEVELTIME_BONUS);
5004       else
5005         PlaySound(SND_GAME_LEVELTIME_BONUS);
5006
5007       return;
5008     }
5009   }
5010
5011   game.panel.active = FALSE;
5012
5013   if (game_over_delay_3 > 0)
5014   {
5015     game_over_delay_3--;
5016
5017     return;
5018   }
5019
5020   GameEnd();
5021 }
5022
5023 void GameEnd(void)
5024 {
5025   // used instead of "level_nr" (needed for network games)
5026   int last_level_nr = levelset.level_nr;
5027   boolean tape_saved = FALSE;
5028
5029   game.LevelSolved_GameEnd = TRUE;
5030
5031   if (game.LevelSolved_SaveTape && !score_info_tape_play)
5032   {
5033     // make sure that request dialog to save tape does not open door again
5034     if (!global.use_envelope_request)
5035       CloseDoor(DOOR_CLOSE_1);
5036
5037     // ask to save tape
5038     tape_saved = SaveTapeChecked_LevelSolved(tape.level_nr);
5039
5040     // set unique basename for score tape (also saved in high score table)
5041     strcpy(tape.score_tape_basename, getScoreTapeBasename(setup.player_name));
5042   }
5043
5044   // if no tape is to be saved, close both doors simultaneously
5045   CloseDoor(DOOR_CLOSE_ALL);
5046
5047   if (level_editor_test_game || score_info_tape_play)
5048   {
5049     SetGameStatus(GAME_MODE_MAIN);
5050
5051     DrawMainMenu();
5052
5053     return;
5054   }
5055
5056   if (!game.LevelSolved_SaveScore)
5057   {
5058     SetGameStatus(GAME_MODE_MAIN);
5059
5060     DrawMainMenu();
5061
5062     return;
5063   }
5064
5065   if (level_nr == leveldir_current->handicap_level)
5066   {
5067     leveldir_current->handicap_level++;
5068
5069     SaveLevelSetup_SeriesInfo();
5070   }
5071
5072   // save score and score tape before potentially erasing tape below
5073   NewHighScore(last_level_nr, tape_saved);
5074
5075   if (setup.increment_levels &&
5076       level_nr < leveldir_current->last_level &&
5077       !network_playing)
5078   {
5079     level_nr++;         // advance to next level
5080     TapeErase();        // start with empty tape
5081
5082     if (setup.auto_play_next_level)
5083     {
5084       scores.continue_playing = TRUE;
5085       scores.next_level_nr = level_nr;
5086
5087       LoadLevel(level_nr);
5088
5089       SaveLevelSetup_SeriesInfo();
5090     }
5091   }
5092
5093   if (scores.last_added >= 0 && setup.show_scores_after_game)
5094   {
5095     SetGameStatus(GAME_MODE_SCORES);
5096
5097     DrawHallOfFame(last_level_nr);
5098   }
5099   else if (scores.continue_playing)
5100   {
5101     StartGameActions(network.enabled, setup.autorecord, level.random_seed);
5102   }
5103   else
5104   {
5105     SetGameStatus(GAME_MODE_MAIN);
5106
5107     DrawMainMenu();
5108   }
5109 }
5110
5111 static int addScoreEntry(struct ScoreInfo *list, struct ScoreEntry *new_entry,
5112                          boolean one_score_entry_per_name)
5113 {
5114   int i;
5115
5116   if (strEqual(new_entry->name, EMPTY_PLAYER_NAME))
5117     return -1;
5118
5119   for (i = 0; i < MAX_SCORE_ENTRIES; i++)
5120   {
5121     struct ScoreEntry *entry = &list->entry[i];
5122     boolean score_is_better = (new_entry->score >  entry->score);
5123     boolean score_is_equal  = (new_entry->score == entry->score);
5124     boolean time_is_better  = (new_entry->time  <  entry->time);
5125     boolean time_is_equal   = (new_entry->time  == entry->time);
5126     boolean better_by_score = (score_is_better ||
5127                                (score_is_equal && time_is_better));
5128     boolean better_by_time  = (time_is_better ||
5129                                (time_is_equal && score_is_better));
5130     boolean is_better = (level.rate_time_over_score ? better_by_time :
5131                          better_by_score);
5132     boolean entry_is_empty = (entry->score == 0 &&
5133                               entry->time == 0);
5134
5135     // prevent adding server score entries if also existing in local score file
5136     // (special case: historic score entries have an empty tape basename entry)
5137     if (strEqual(new_entry->tape_basename, entry->tape_basename) &&
5138         !strEqual(new_entry->tape_basename, UNDEFINED_FILENAME))
5139     {
5140       // add fields from server score entry not stored in local score entry
5141       // (currently, this means setting platform, version and country fields;
5142       // in rare cases, this may also correct an invalid score value, as
5143       // historic scores might have been truncated to 16-bit values locally)
5144       *entry = *new_entry;
5145
5146       return -1;
5147     }
5148
5149     if (is_better || entry_is_empty)
5150     {
5151       // player has made it to the hall of fame
5152
5153       if (i < MAX_SCORE_ENTRIES - 1)
5154       {
5155         int m = MAX_SCORE_ENTRIES - 1;
5156         int l;
5157
5158         if (one_score_entry_per_name)
5159         {
5160           for (l = i; l < MAX_SCORE_ENTRIES; l++)
5161             if (strEqual(list->entry[l].name, new_entry->name))
5162               m = l;
5163
5164           if (m == i)   // player's new highscore overwrites his old one
5165             goto put_into_list;
5166         }
5167
5168         for (l = m; l > i; l--)
5169           list->entry[l] = list->entry[l - 1];
5170       }
5171
5172       put_into_list:
5173
5174       *entry = *new_entry;
5175
5176       return i;
5177     }
5178     else if (one_score_entry_per_name &&
5179              strEqual(entry->name, new_entry->name))
5180     {
5181       // player already in high score list with better score or time
5182
5183       return -1;
5184     }
5185   }
5186
5187   // special case: new score is beyond the last high score list position
5188   return MAX_SCORE_ENTRIES;
5189 }
5190
5191 void NewHighScore(int level_nr, boolean tape_saved)
5192 {
5193   struct ScoreEntry new_entry = {{ 0 }}; // (prevent warning from GCC bug 53119)
5194   boolean one_per_name = FALSE;
5195
5196   strncpy(new_entry.tape_basename, tape.score_tape_basename, MAX_FILENAME_LEN);
5197   strncpy(new_entry.name, setup.player_name, MAX_PLAYER_NAME_LEN);
5198
5199   new_entry.score = game.score_final;
5200   new_entry.time = game.score_time_final;
5201
5202   LoadScore(level_nr);
5203
5204   scores.last_added = addScoreEntry(&scores, &new_entry, one_per_name);
5205
5206   if (scores.last_added >= MAX_SCORE_ENTRIES)
5207   {
5208     scores.last_added = MAX_SCORE_ENTRIES - 1;
5209     scores.force_last_added = TRUE;
5210
5211     scores.entry[scores.last_added] = new_entry;
5212
5213     // store last added local score entry (before merging server scores)
5214     scores.last_added_local = scores.last_added;
5215
5216     return;
5217   }
5218
5219   if (scores.last_added < 0)
5220     return;
5221
5222   SaveScore(level_nr);
5223
5224   // store last added local score entry (before merging server scores)
5225   scores.last_added_local = scores.last_added;
5226
5227   if (!game.LevelSolved_SaveTape)
5228     return;
5229
5230   SaveScoreTape(level_nr);
5231
5232   if (setup.ask_for_using_api_server)
5233   {
5234     setup.use_api_server =
5235       Request("Upload your score and tape to the high score server?", REQ_ASK);
5236
5237     if (!setup.use_api_server)
5238       Request("Not using high score server! Use setup menu to enable again!",
5239               REQ_CONFIRM);
5240
5241     runtime.use_api_server = setup.use_api_server;
5242
5243     // after asking for using API server once, do not ask again
5244     setup.ask_for_using_api_server = FALSE;
5245
5246     SaveSetup_ServerSetup();
5247   }
5248
5249   SaveServerScore(level_nr, tape_saved);
5250 }
5251
5252 void MergeServerScore(void)
5253 {
5254   struct ScoreEntry last_added_entry;
5255   boolean one_per_name = FALSE;
5256   int i;
5257
5258   if (scores.last_added >= 0)
5259     last_added_entry = scores.entry[scores.last_added];
5260
5261   for (i = 0; i < server_scores.num_entries; i++)
5262   {
5263     int pos = addScoreEntry(&scores, &server_scores.entry[i], one_per_name);
5264
5265     if (pos >= 0 && pos <= scores.last_added)
5266       scores.last_added++;
5267   }
5268
5269   if (scores.last_added >= MAX_SCORE_ENTRIES)
5270   {
5271     scores.last_added = MAX_SCORE_ENTRIES - 1;
5272     scores.force_last_added = TRUE;
5273
5274     scores.entry[scores.last_added] = last_added_entry;
5275   }
5276 }
5277
5278 static int getElementMoveStepsizeExt(int x, int y, int direction)
5279 {
5280   int element = Tile[x][y];
5281   int dx = (direction == MV_LEFT ? -1 : direction == MV_RIGHT ? +1 : 0);
5282   int dy = (direction == MV_UP   ? -1 : direction == MV_DOWN  ? +1 : 0);
5283   int horiz_move = (dx != 0);
5284   int sign = (horiz_move ? dx : dy);
5285   int step = sign * element_info[element].move_stepsize;
5286
5287   // special values for move stepsize for spring and things on conveyor belt
5288   if (horiz_move)
5289   {
5290     if (CAN_FALL(element) &&
5291         y < lev_fieldy - 1 && IS_BELT_ACTIVE(Tile[x][y + 1]))
5292       step = sign * MOVE_STEPSIZE_NORMAL / 2;
5293     else if (element == EL_SPRING)
5294       step = sign * MOVE_STEPSIZE_NORMAL * 2;
5295   }
5296
5297   return step;
5298 }
5299
5300 static int getElementMoveStepsize(int x, int y)
5301 {
5302   return getElementMoveStepsizeExt(x, y, MovDir[x][y]);
5303 }
5304
5305 void InitPlayerGfxAnimation(struct PlayerInfo *player, int action, int dir)
5306 {
5307   if (player->GfxAction != action || player->GfxDir != dir)
5308   {
5309     player->GfxAction = action;
5310     player->GfxDir = dir;
5311     player->Frame = 0;
5312     player->StepFrame = 0;
5313   }
5314 }
5315
5316 static void ResetGfxFrame(int x, int y)
5317 {
5318   // profiling showed that "autotest" spends 10~20% of its time in this function
5319   if (DrawingDeactivatedField())
5320     return;
5321
5322   int element = Tile[x][y];
5323   int graphic = el_act_dir2img(element, GfxAction[x][y], GfxDir[x][y]);
5324
5325   if (graphic_info[graphic].anim_global_sync)
5326     GfxFrame[x][y] = FrameCounter;
5327   else if (graphic_info[graphic].anim_global_anim_sync)
5328     GfxFrame[x][y] = getGlobalAnimSyncFrame();
5329   else if (ANIM_MODE(graphic) == ANIM_CE_VALUE)
5330     GfxFrame[x][y] = CustomValue[x][y];
5331   else if (ANIM_MODE(graphic) == ANIM_CE_SCORE)
5332     GfxFrame[x][y] = element_info[element].collect_score;
5333   else if (ANIM_MODE(graphic) == ANIM_CE_DELAY)
5334     GfxFrame[x][y] = ChangeDelay[x][y];
5335 }
5336
5337 static void ResetGfxAnimation(int x, int y)
5338 {
5339   GfxAction[x][y] = ACTION_DEFAULT;
5340   GfxDir[x][y] = MovDir[x][y];
5341   GfxFrame[x][y] = 0;
5342
5343   ResetGfxFrame(x, y);
5344 }
5345
5346 static void ResetRandomAnimationValue(int x, int y)
5347 {
5348   GfxRandom[x][y] = INIT_GFX_RANDOM();
5349 }
5350
5351 static void InitMovingField(int x, int y, int direction)
5352 {
5353   int element = Tile[x][y];
5354   int dx = (direction == MV_LEFT ? -1 : direction == MV_RIGHT ? +1 : 0);
5355   int dy = (direction == MV_UP   ? -1 : direction == MV_DOWN  ? +1 : 0);
5356   int newx = x + dx;
5357   int newy = y + dy;
5358   boolean is_moving_before, is_moving_after;
5359
5360   // check if element was/is moving or being moved before/after mode change
5361   is_moving_before = (WasJustMoving[x][y] != 0);
5362   is_moving_after  = (getElementMoveStepsizeExt(x, y, direction)    != 0);
5363
5364   // reset animation only for moving elements which change direction of moving
5365   // or which just started or stopped moving
5366   // (else CEs with property "can move" / "not moving" are reset each frame)
5367   if (is_moving_before != is_moving_after ||
5368       direction != MovDir[x][y])
5369     ResetGfxAnimation(x, y);
5370
5371   MovDir[x][y] = direction;
5372   GfxDir[x][y] = direction;
5373
5374   GfxAction[x][y] = (!is_moving_after ? ACTION_WAITING :
5375                      direction == MV_DOWN && CAN_FALL(element) ?
5376                      ACTION_FALLING : ACTION_MOVING);
5377
5378   // this is needed for CEs with property "can move" / "not moving"
5379
5380   if (is_moving_after)
5381   {
5382     if (Tile[newx][newy] == EL_EMPTY)
5383       Tile[newx][newy] = EL_BLOCKED;
5384
5385     MovDir[newx][newy] = MovDir[x][y];
5386
5387     CustomValue[newx][newy] = CustomValue[x][y];
5388
5389     GfxFrame[newx][newy] = GfxFrame[x][y];
5390     GfxRandom[newx][newy] = GfxRandom[x][y];
5391     GfxAction[newx][newy] = GfxAction[x][y];
5392     GfxDir[newx][newy] = GfxDir[x][y];
5393   }
5394 }
5395
5396 void Moving2Blocked(int x, int y, int *goes_to_x, int *goes_to_y)
5397 {
5398   int direction = MovDir[x][y];
5399   int newx = x + (direction & MV_LEFT ? -1 : direction & MV_RIGHT ? +1 : 0);
5400   int newy = y + (direction & MV_UP   ? -1 : direction & MV_DOWN  ? +1 : 0);
5401
5402   *goes_to_x = newx;
5403   *goes_to_y = newy;
5404 }
5405
5406 void Blocked2Moving(int x, int y, int *comes_from_x, int *comes_from_y)
5407 {
5408   int direction = MovDir[x][y];
5409   int oldx = x + (direction & MV_LEFT ? +1 : direction & MV_RIGHT ? -1 : 0);
5410   int oldy = y + (direction & MV_UP   ? +1 : direction & MV_DOWN  ? -1 : 0);
5411
5412   *comes_from_x = oldx;
5413   *comes_from_y = oldy;
5414 }
5415
5416 static int MovingOrBlocked2Element(int x, int y)
5417 {
5418   int element = Tile[x][y];
5419
5420   if (element == EL_BLOCKED)
5421   {
5422     int oldx, oldy;
5423
5424     Blocked2Moving(x, y, &oldx, &oldy);
5425
5426     return Tile[oldx][oldy];
5427   }
5428
5429   return element;
5430 }
5431
5432 static int MovingOrBlocked2ElementIfNotLeaving(int x, int y)
5433 {
5434   // like MovingOrBlocked2Element(), but if element is moving
5435   // and (x, y) is the field the moving element is just leaving,
5436   // return EL_BLOCKED instead of the element value
5437   int element = Tile[x][y];
5438
5439   if (IS_MOVING(x, y))
5440   {
5441     if (element == EL_BLOCKED)
5442     {
5443       int oldx, oldy;
5444
5445       Blocked2Moving(x, y, &oldx, &oldy);
5446       return Tile[oldx][oldy];
5447     }
5448     else
5449       return EL_BLOCKED;
5450   }
5451   else
5452     return element;
5453 }
5454
5455 static void RemoveField(int x, int y)
5456 {
5457   Tile[x][y] = EL_EMPTY;
5458
5459   MovPos[x][y] = 0;
5460   MovDir[x][y] = 0;
5461   MovDelay[x][y] = 0;
5462
5463   CustomValue[x][y] = 0;
5464
5465   AmoebaNr[x][y] = 0;
5466   ChangeDelay[x][y] = 0;
5467   ChangePage[x][y] = -1;
5468   Pushed[x][y] = FALSE;
5469
5470   GfxElement[x][y] = EL_UNDEFINED;
5471   GfxAction[x][y] = ACTION_DEFAULT;
5472   GfxDir[x][y] = MV_NONE;
5473 }
5474
5475 static void RemoveMovingField(int x, int y)
5476 {
5477   int oldx = x, oldy = y, newx = x, newy = y;
5478   int element = Tile[x][y];
5479   int next_element = EL_UNDEFINED;
5480
5481   if (element != EL_BLOCKED && !IS_MOVING(x, y))
5482     return;
5483
5484   if (IS_MOVING(x, y))
5485   {
5486     Moving2Blocked(x, y, &newx, &newy);
5487
5488     if (Tile[newx][newy] != EL_BLOCKED)
5489     {
5490       // element is moving, but target field is not free (blocked), but
5491       // already occupied by something different (example: acid pool);
5492       // in this case, only remove the moving field, but not the target
5493
5494       RemoveField(oldx, oldy);
5495
5496       Store[oldx][oldy] = Store2[oldx][oldy] = 0;
5497
5498       TEST_DrawLevelField(oldx, oldy);
5499
5500       return;
5501     }
5502   }
5503   else if (element == EL_BLOCKED)
5504   {
5505     Blocked2Moving(x, y, &oldx, &oldy);
5506     if (!IS_MOVING(oldx, oldy))
5507       return;
5508   }
5509
5510   if (element == EL_BLOCKED &&
5511       (Tile[oldx][oldy] == EL_QUICKSAND_EMPTYING ||
5512        Tile[oldx][oldy] == EL_QUICKSAND_FAST_EMPTYING ||
5513        Tile[oldx][oldy] == EL_MAGIC_WALL_EMPTYING ||
5514        Tile[oldx][oldy] == EL_BD_MAGIC_WALL_EMPTYING ||
5515        Tile[oldx][oldy] == EL_DC_MAGIC_WALL_EMPTYING ||
5516        Tile[oldx][oldy] == EL_AMOEBA_DROPPING))
5517     next_element = get_next_element(Tile[oldx][oldy]);
5518
5519   RemoveField(oldx, oldy);
5520   RemoveField(newx, newy);
5521
5522   Store[oldx][oldy] = Store2[oldx][oldy] = 0;
5523
5524   if (next_element != EL_UNDEFINED)
5525     Tile[oldx][oldy] = next_element;
5526
5527   TEST_DrawLevelField(oldx, oldy);
5528   TEST_DrawLevelField(newx, newy);
5529 }
5530
5531 void DrawDynamite(int x, int y)
5532 {
5533   int sx = SCREENX(x), sy = SCREENY(y);
5534   int graphic = el2img(Tile[x][y]);
5535   int frame;
5536
5537   if (!IN_SCR_FIELD(sx, sy) || IS_PLAYER(x, y))
5538     return;
5539
5540   if (IS_WALKABLE_INSIDE(Back[x][y]))
5541     return;
5542
5543   if (Back[x][y])
5544     DrawLevelElement(x, y, Back[x][y]);
5545   else if (Store[x][y])
5546     DrawLevelElement(x, y, Store[x][y]);
5547   else if (game.use_masked_elements)
5548     DrawLevelElement(x, y, EL_EMPTY);
5549
5550   frame = getGraphicAnimationFrameXY(graphic, x, y);
5551
5552   if (Back[x][y] || Store[x][y] || game.use_masked_elements)
5553     DrawGraphicThruMask(sx, sy, graphic, frame);
5554   else
5555     DrawGraphic(sx, sy, graphic, frame);
5556 }
5557
5558 static void CheckDynamite(int x, int y)
5559 {
5560   if (MovDelay[x][y] != 0)      // dynamite is still waiting to explode
5561   {
5562     MovDelay[x][y]--;
5563
5564     if (MovDelay[x][y] != 0)
5565     {
5566       DrawDynamite(x, y);
5567       PlayLevelSoundActionIfLoop(x, y, ACTION_ACTIVE);
5568
5569       return;
5570     }
5571   }
5572
5573   StopLevelSoundActionIfLoop(x, y, ACTION_ACTIVE);
5574
5575   Bang(x, y);
5576 }
5577
5578 static void setMinimalPlayerBoundaries(int *sx1, int *sy1, int *sx2, int *sy2)
5579 {
5580   boolean num_checked_players = 0;
5581   int i;
5582
5583   for (i = 0; i < MAX_PLAYERS; i++)
5584   {
5585     if (stored_player[i].active)
5586     {
5587       int sx = stored_player[i].jx;
5588       int sy = stored_player[i].jy;
5589
5590       if (num_checked_players == 0)
5591       {
5592         *sx1 = *sx2 = sx;
5593         *sy1 = *sy2 = sy;
5594       }
5595       else
5596       {
5597         *sx1 = MIN(*sx1, sx);
5598         *sy1 = MIN(*sy1, sy);
5599         *sx2 = MAX(*sx2, sx);
5600         *sy2 = MAX(*sy2, sy);
5601       }
5602
5603       num_checked_players++;
5604     }
5605   }
5606 }
5607
5608 static boolean checkIfAllPlayersFitToScreen_RND(void)
5609 {
5610   int sx1 = 0, sy1 = 0, sx2 = 0, sy2 = 0;
5611
5612   setMinimalPlayerBoundaries(&sx1, &sy1, &sx2, &sy2);
5613
5614   return (sx2 - sx1 < SCR_FIELDX &&
5615           sy2 - sy1 < SCR_FIELDY);
5616 }
5617
5618 static void setScreenCenteredToAllPlayers(int *sx, int *sy)
5619 {
5620   int sx1 = scroll_x, sy1 = scroll_y, sx2 = scroll_x, sy2 = scroll_y;
5621
5622   setMinimalPlayerBoundaries(&sx1, &sy1, &sx2, &sy2);
5623
5624   *sx = (sx1 + sx2) / 2;
5625   *sy = (sy1 + sy2) / 2;
5626 }
5627
5628 static void DrawRelocateScreen(int old_x, int old_y, int x, int y,
5629                                boolean center_screen, boolean quick_relocation)
5630 {
5631   unsigned int frame_delay_value_old = GetVideoFrameDelay();
5632   boolean ffwd_delay = (tape.playing && tape.fast_forward);
5633   boolean no_delay = (tape.warp_forward);
5634   int frame_delay_value = (ffwd_delay ? FfwdFrameDelay : GameFrameDelay);
5635   int wait_delay_value = (no_delay ? 0 : frame_delay_value);
5636   int new_scroll_x, new_scroll_y;
5637
5638   if (level.lazy_relocation && IN_VIS_FIELD(SCREENX(x), SCREENY(y)))
5639   {
5640     // case 1: quick relocation inside visible screen (without scrolling)
5641
5642     RedrawPlayfield();
5643
5644     return;
5645   }
5646
5647   if (!level.shifted_relocation || center_screen)
5648   {
5649     // relocation _with_ centering of screen
5650
5651     new_scroll_x = SCROLL_POSITION_X(x);
5652     new_scroll_y = SCROLL_POSITION_Y(y);
5653   }
5654   else
5655   {
5656     // relocation _without_ centering of screen
5657
5658     int center_scroll_x = SCROLL_POSITION_X(old_x);
5659     int center_scroll_y = SCROLL_POSITION_Y(old_y);
5660     int offset_x = x + (scroll_x - center_scroll_x);
5661     int offset_y = y + (scroll_y - center_scroll_y);
5662
5663     // for new screen position, apply previous offset to center position
5664     new_scroll_x = SCROLL_POSITION_X(offset_x);
5665     new_scroll_y = SCROLL_POSITION_Y(offset_y);
5666   }
5667
5668   if (quick_relocation)
5669   {
5670     // case 2: quick relocation (redraw without visible scrolling)
5671
5672     scroll_x = new_scroll_x;
5673     scroll_y = new_scroll_y;
5674
5675     RedrawPlayfield();
5676
5677     return;
5678   }
5679
5680   // case 3: visible relocation (with scrolling to new position)
5681
5682   ScrollScreen(NULL, SCROLL_GO_ON);     // scroll last frame to full tile
5683
5684   SetVideoFrameDelay(wait_delay_value);
5685
5686   while (scroll_x != new_scroll_x || scroll_y != new_scroll_y)
5687   {
5688     int dx = (new_scroll_x < scroll_x ? +1 : new_scroll_x > scroll_x ? -1 : 0);
5689     int dy = (new_scroll_y < scroll_y ? +1 : new_scroll_y > scroll_y ? -1 : 0);
5690
5691     if (dx == 0 && dy == 0)             // no scrolling needed at all
5692       break;
5693
5694     scroll_x -= dx;
5695     scroll_y -= dy;
5696
5697     // set values for horizontal/vertical screen scrolling (half tile size)
5698     int dir_x = (dx != 0 ? MV_HORIZONTAL : 0);
5699     int dir_y = (dy != 0 ? MV_VERTICAL   : 0);
5700     int pos_x = dx * TILEX / 2;
5701     int pos_y = dy * TILEY / 2;
5702     int fx = getFieldbufferOffsetX_RND(dir_x, pos_x);
5703     int fy = getFieldbufferOffsetY_RND(dir_y, pos_y);
5704
5705     ScrollLevel(dx, dy);
5706     DrawAllPlayers();
5707
5708     // scroll in two steps of half tile size to make things smoother
5709     BlitScreenToBitmapExt_RND(window, fx, fy);
5710
5711     // scroll second step to align at full tile size
5712     BlitScreenToBitmap(window);
5713   }
5714
5715   DrawAllPlayers();
5716   BackToFront();
5717
5718   SetVideoFrameDelay(frame_delay_value_old);
5719 }
5720
5721 static void RelocatePlayer(int jx, int jy, int el_player_raw)
5722 {
5723   int el_player = GET_PLAYER_ELEMENT(el_player_raw);
5724   int player_nr = GET_PLAYER_NR(el_player);
5725   struct PlayerInfo *player = &stored_player[player_nr];
5726   boolean ffwd_delay = (tape.playing && tape.fast_forward);
5727   boolean no_delay = (tape.warp_forward);
5728   int frame_delay_value = (ffwd_delay ? FfwdFrameDelay : GameFrameDelay);
5729   int wait_delay_value = (no_delay ? 0 : frame_delay_value);
5730   int old_jx = player->jx;
5731   int old_jy = player->jy;
5732   int old_element = Tile[old_jx][old_jy];
5733   int element = Tile[jx][jy];
5734   boolean player_relocated = (old_jx != jx || old_jy != jy);
5735
5736   int move_dir_horiz = (jx < old_jx ? MV_LEFT : jx > old_jx ? MV_RIGHT : 0);
5737   int move_dir_vert  = (jy < old_jy ? MV_UP   : jy > old_jy ? MV_DOWN  : 0);
5738   int enter_side_horiz = MV_DIR_OPPOSITE(move_dir_horiz);
5739   int enter_side_vert  = MV_DIR_OPPOSITE(move_dir_vert);
5740   int leave_side_horiz = move_dir_horiz;
5741   int leave_side_vert  = move_dir_vert;
5742   int enter_side = enter_side_horiz | enter_side_vert;
5743   int leave_side = leave_side_horiz | leave_side_vert;
5744
5745   if (player->buried)           // do not reanimate dead player
5746     return;
5747
5748   if (!player_relocated)        // no need to relocate the player
5749     return;
5750
5751   if (IS_PLAYER(jx, jy))        // player already placed at new position
5752   {
5753     RemoveField(jx, jy);        // temporarily remove newly placed player
5754     DrawLevelField(jx, jy);
5755   }
5756
5757   if (player->present)
5758   {
5759     while (player->MovPos)
5760     {
5761       ScrollPlayer(player, SCROLL_GO_ON);
5762       ScrollScreen(NULL, SCROLL_GO_ON);
5763
5764       AdvanceFrameAndPlayerCounters(player->index_nr);
5765
5766       DrawPlayer(player);
5767
5768       BackToFront_WithFrameDelay(wait_delay_value);
5769     }
5770
5771     DrawPlayer(player);         // needed here only to cleanup last field
5772     DrawLevelField(player->jx, player->jy);     // remove player graphic
5773
5774     player->is_moving = FALSE;
5775   }
5776
5777   if (IS_CUSTOM_ELEMENT(old_element))
5778     CheckElementChangeByPlayer(old_jx, old_jy, old_element,
5779                                CE_LEFT_BY_PLAYER,
5780                                player->index_bit, leave_side);
5781
5782   CheckTriggeredElementChangeByPlayer(old_jx, old_jy, old_element,
5783                                       CE_PLAYER_LEAVES_X,
5784                                       player->index_bit, leave_side);
5785
5786   Tile[jx][jy] = el_player;
5787   InitPlayerField(jx, jy, el_player, TRUE);
5788
5789   /* "InitPlayerField()" above sets Tile[jx][jy] to EL_EMPTY, but it may be
5790      possible that the relocation target field did not contain a player element,
5791      but a walkable element, to which the new player was relocated -- in this
5792      case, restore that (already initialized!) element on the player field */
5793   if (!IS_PLAYER_ELEMENT(element))      // player may be set on walkable element
5794   {
5795     Tile[jx][jy] = element;     // restore previously existing element
5796   }
5797
5798   // only visually relocate centered player
5799   DrawRelocateScreen(old_jx, old_jy, player->jx, player->jy,
5800                      FALSE, level.instant_relocation);
5801
5802   TestIfPlayerTouchesBadThing(jx, jy);
5803   TestIfPlayerTouchesCustomElement(jx, jy);
5804
5805   if (IS_CUSTOM_ELEMENT(element))
5806     CheckElementChangeByPlayer(jx, jy, element, CE_ENTERED_BY_PLAYER,
5807                                player->index_bit, enter_side);
5808
5809   CheckTriggeredElementChangeByPlayer(jx, jy, element, CE_PLAYER_ENTERS_X,
5810                                       player->index_bit, enter_side);
5811
5812   if (player->is_switching)
5813   {
5814     /* ensure that relocation while still switching an element does not cause
5815        a new element to be treated as also switched directly after relocation
5816        (this is important for teleporter switches that teleport the player to
5817        a place where another teleporter switch is in the same direction, which
5818        would then incorrectly be treated as immediately switched before the
5819        direction key that caused the switch was released) */
5820
5821     player->switch_x += jx - old_jx;
5822     player->switch_y += jy - old_jy;
5823   }
5824 }
5825
5826 static void Explode(int ex, int ey, int phase, int mode)
5827 {
5828   int x, y;
5829   int last_phase;
5830   int border_element;
5831
5832   if (game.explosions_delayed)
5833   {
5834     ExplodeField[ex][ey] = mode;
5835     return;
5836   }
5837
5838   if (phase == EX_PHASE_START)          // initialize 'Store[][]' field
5839   {
5840     int center_element = Tile[ex][ey];
5841     int ce_value = CustomValue[ex][ey];
5842     int ce_score = element_info[center_element].collect_score;
5843     int artwork_element, explosion_element;     // set these values later
5844
5845     // remove things displayed in background while burning dynamite
5846     if (Back[ex][ey] != EL_EMPTY && !IS_INDESTRUCTIBLE(Back[ex][ey]))
5847       Back[ex][ey] = 0;
5848
5849     if (IS_MOVING(ex, ey) || IS_BLOCKED(ex, ey))
5850     {
5851       // put moving element to center field (and let it explode there)
5852       center_element = MovingOrBlocked2Element(ex, ey);
5853       RemoveMovingField(ex, ey);
5854       Tile[ex][ey] = center_element;
5855     }
5856
5857     // now "center_element" is finally determined -- set related values now
5858     artwork_element = center_element;           // for custom player artwork
5859     explosion_element = center_element;         // for custom player artwork
5860
5861     if (IS_PLAYER(ex, ey))
5862     {
5863       int player_nr = GET_PLAYER_NR(StorePlayer[ex][ey]);
5864
5865       artwork_element = stored_player[player_nr].artwork_element;
5866
5867       if (level.use_explosion_element[player_nr])
5868       {
5869         explosion_element = level.explosion_element[player_nr];
5870         artwork_element = explosion_element;
5871       }
5872     }
5873
5874     if (mode == EX_TYPE_NORMAL ||
5875         mode == EX_TYPE_CENTER ||
5876         mode == EX_TYPE_CROSS)
5877       PlayLevelSoundElementAction(ex, ey, artwork_element, ACTION_EXPLODING);
5878
5879     last_phase = element_info[explosion_element].explosion_delay + 1;
5880
5881     for (y = ey - 1; y <= ey + 1; y++) for (x = ex - 1; x <= ex + 1; x++)
5882     {
5883       int xx = x - ex + 1;
5884       int yy = y - ey + 1;
5885       int element;
5886
5887       if (!IN_LEV_FIELD(x, y) ||
5888           (mode & EX_TYPE_SINGLE_TILE && (x != ex || y != ey)) ||
5889           (mode == EX_TYPE_CROSS      && (x != ex && y != ey)))
5890         continue;
5891
5892       element = Tile[x][y];
5893
5894       if (IS_MOVING(x, y) || IS_BLOCKED(x, y))
5895       {
5896         element = MovingOrBlocked2Element(x, y);
5897
5898         if (!IS_EXPLOSION_PROOF(element))
5899           RemoveMovingField(x, y);
5900       }
5901
5902       // indestructible elements can only explode in center (but not flames)
5903       if ((IS_EXPLOSION_PROOF(element) && (x != ex || y != ey ||
5904                                            mode == EX_TYPE_BORDER)) ||
5905           element == EL_FLAMES)
5906         continue;
5907
5908       /* no idea why this was changed from 3.0.8 to 3.1.0 -- this causes buggy
5909          behaviour, for example when touching a yamyam that explodes to rocks
5910          with active deadly shield, a rock is created under the player !!! */
5911       // (case 1 (surely buggy): >= 3.1.0, case 2 (maybe buggy): <= 3.0.8)
5912 #if 0
5913       if (IS_PLAYER(x, y) && SHIELD_ON(PLAYERINFO(x, y)) &&
5914           (game.engine_version < VERSION_IDENT(3,1,0,0) ||
5915            (x == ex && y == ey && mode != EX_TYPE_BORDER)))
5916 #else
5917       if (IS_PLAYER(x, y) && SHIELD_ON(PLAYERINFO(x, y)))
5918 #endif
5919       {
5920         if (IS_ACTIVE_BOMB(element))
5921         {
5922           // re-activate things under the bomb like gate or penguin
5923           Tile[x][y] = (Back[x][y] ? Back[x][y] : EL_EMPTY);
5924           Back[x][y] = 0;
5925         }
5926
5927         continue;
5928       }
5929
5930       // save walkable background elements while explosion on same tile
5931       if (IS_WALKABLE(element) && IS_INDESTRUCTIBLE(element) &&
5932           (x != ex || y != ey || mode == EX_TYPE_BORDER))
5933         Back[x][y] = element;
5934
5935       // ignite explodable elements reached by other explosion
5936       if (element == EL_EXPLOSION)
5937         element = Store2[x][y];
5938
5939       if (AmoebaNr[x][y] &&
5940           (element == EL_AMOEBA_FULL ||
5941            element == EL_BD_AMOEBA ||
5942            element == EL_AMOEBA_GROWING))
5943       {
5944         AmoebaCnt[AmoebaNr[x][y]]--;
5945         AmoebaCnt2[AmoebaNr[x][y]]--;
5946       }
5947
5948       RemoveField(x, y);
5949
5950       if (IS_PLAYER(ex, ey) && !PLAYER_EXPLOSION_PROTECTED(ex, ey))
5951       {
5952         int player_nr = StorePlayer[ex][ey] - EL_PLAYER_1;
5953
5954         Store[x][y] = EL_PLAYER_IS_EXPLODING_1 + player_nr;
5955
5956         if (PLAYERINFO(ex, ey)->use_murphy)
5957           Store[x][y] = EL_EMPTY;
5958       }
5959
5960       // !!! check this case -- currently needed for rnd_rado_negundo_v,
5961       // !!! levels 015 018 019 020 021 022 023 026 027 028 !!!
5962       else if (IS_PLAYER_ELEMENT(center_element))
5963         Store[x][y] = EL_EMPTY;
5964       else if (center_element == EL_YAMYAM)
5965         Store[x][y] = level.yamyam_content[game.yamyam_content_nr].e[xx][yy];
5966       else if (element_info[center_element].content.e[xx][yy] != EL_EMPTY)
5967         Store[x][y] = element_info[center_element].content.e[xx][yy];
5968 #if 1
5969       // needed because EL_BD_BUTTERFLY is not defined as "CAN_EXPLODE"
5970       // (killing EL_BD_BUTTERFLY with dynamite would result in BD diamond
5971       // otherwise) -- FIX THIS !!!
5972       else if (!CAN_EXPLODE(element) && element != EL_BD_BUTTERFLY)
5973         Store[x][y] = element_info[element].content.e[1][1];
5974 #else
5975       else if (!CAN_EXPLODE(element))
5976         Store[x][y] = element_info[element].content.e[1][1];
5977 #endif
5978       else
5979         Store[x][y] = EL_EMPTY;
5980
5981       if (IS_CUSTOM_ELEMENT(center_element))
5982         Store[x][y] = (Store[x][y] == EL_CURRENT_CE_VALUE ? ce_value :
5983                        Store[x][y] == EL_CURRENT_CE_SCORE ? ce_score :
5984                        Store[x][y] >= EL_PREV_CE_8 &&
5985                        Store[x][y] <= EL_NEXT_CE_8 ?
5986                        RESOLVED_REFERENCE_ELEMENT(center_element, Store[x][y]) :
5987                        Store[x][y]);
5988
5989       if (x != ex || y != ey || mode == EX_TYPE_BORDER ||
5990           center_element == EL_AMOEBA_TO_DIAMOND)
5991         Store2[x][y] = element;
5992
5993       Tile[x][y] = EL_EXPLOSION;
5994       GfxElement[x][y] = artwork_element;
5995
5996       ExplodePhase[x][y] = 1;
5997       ExplodeDelay[x][y] = last_phase;
5998
5999       Stop[x][y] = TRUE;
6000     }
6001
6002     if (center_element == EL_YAMYAM)
6003       game.yamyam_content_nr =
6004         (game.yamyam_content_nr + 1) % level.num_yamyam_contents;
6005
6006     return;
6007   }
6008
6009   if (Stop[ex][ey])
6010     return;
6011
6012   x = ex;
6013   y = ey;
6014
6015   if (phase == 1)
6016     GfxFrame[x][y] = 0;         // restart explosion animation
6017
6018   last_phase = ExplodeDelay[x][y];
6019
6020   ExplodePhase[x][y] = (phase < last_phase ? phase + 1 : 0);
6021
6022   // this can happen if the player leaves an explosion just in time
6023   if (GfxElement[x][y] == EL_UNDEFINED)
6024     GfxElement[x][y] = EL_EMPTY;
6025
6026   border_element = Store2[x][y];
6027   if (IS_PLAYER(x, y) && !PLAYER_EXPLOSION_PROTECTED(x, y))
6028     border_element = StorePlayer[x][y];
6029
6030   if (phase == element_info[border_element].ignition_delay ||
6031       phase == last_phase)
6032   {
6033     boolean border_explosion = FALSE;
6034
6035     if (IS_PLAYER(x, y) && PLAYERINFO(x, y)->present &&
6036         !PLAYER_EXPLOSION_PROTECTED(x, y))
6037     {
6038       KillPlayerUnlessExplosionProtected(x, y);
6039       border_explosion = TRUE;
6040     }
6041     else if (CAN_EXPLODE_BY_EXPLOSION(border_element))
6042     {
6043       Tile[x][y] = Store2[x][y];
6044       Store2[x][y] = 0;
6045       Bang(x, y);
6046       border_explosion = TRUE;
6047     }
6048     else if (border_element == EL_AMOEBA_TO_DIAMOND)
6049     {
6050       AmoebaToDiamond(x, y);
6051       Store2[x][y] = 0;
6052       border_explosion = TRUE;
6053     }
6054
6055     // if an element just explodes due to another explosion (chain-reaction),
6056     // do not immediately end the new explosion when it was the last frame of
6057     // the explosion (as it would be done in the following "if"-statement!)
6058     if (border_explosion && phase == last_phase)
6059       return;
6060   }
6061
6062   // this can happen if the player was just killed by an explosion
6063   if (GfxElement[x][y] == EL_UNDEFINED)
6064     GfxElement[x][y] = EL_EMPTY;
6065
6066   if (phase == last_phase)
6067   {
6068     int element;
6069
6070     element = Tile[x][y] = Store[x][y];
6071     Store[x][y] = Store2[x][y] = 0;
6072     GfxElement[x][y] = EL_UNDEFINED;
6073
6074     // player can escape from explosions and might therefore be still alive
6075     if (element >= EL_PLAYER_IS_EXPLODING_1 &&
6076         element <= EL_PLAYER_IS_EXPLODING_4)
6077     {
6078       int player_nr = element - EL_PLAYER_IS_EXPLODING_1;
6079       int explosion_element = EL_PLAYER_1 + player_nr;
6080       int xx = MIN(MAX(0, x - stored_player[player_nr].jx + 1), 2);
6081       int yy = MIN(MAX(0, y - stored_player[player_nr].jy + 1), 2);
6082
6083       if (level.use_explosion_element[player_nr])
6084         explosion_element = level.explosion_element[player_nr];
6085
6086       Tile[x][y] = (stored_player[player_nr].active ? EL_EMPTY :
6087                     element_info[explosion_element].content.e[xx][yy]);
6088     }
6089
6090     // restore probably existing indestructible background element
6091     if (Back[x][y] && IS_INDESTRUCTIBLE(Back[x][y]))
6092       element = Tile[x][y] = Back[x][y];
6093     Back[x][y] = 0;
6094
6095     MovDir[x][y] = MovPos[x][y] = MovDelay[x][y] = 0;
6096     GfxDir[x][y] = MV_NONE;
6097     ChangeDelay[x][y] = 0;
6098     ChangePage[x][y] = -1;
6099
6100     CustomValue[x][y] = 0;
6101
6102     InitField_WithBug2(x, y, FALSE);
6103
6104     TEST_DrawLevelField(x, y);
6105
6106     TestIfElementTouchesCustomElement(x, y);
6107
6108     if (GFX_CRUMBLED(element))
6109       TEST_DrawLevelFieldCrumbledNeighbours(x, y);
6110
6111     if (IS_PLAYER(x, y) && !PLAYERINFO(x, y)->present)
6112       StorePlayer[x][y] = 0;
6113
6114     if (IS_PLAYER_ELEMENT(element))
6115       RelocatePlayer(x, y, element);
6116   }
6117   else if (IN_SCR_FIELD(SCREENX(x), SCREENY(y)))
6118   {
6119     int graphic = el_act2img(GfxElement[x][y], ACTION_EXPLODING);
6120     int frame = getGraphicAnimationFrameXY(graphic, x, y);
6121
6122     if (phase == 1)
6123       TEST_DrawLevelFieldCrumbled(x, y);
6124
6125     if (IS_WALKABLE_OVER(Back[x][y]) && Back[x][y] != EL_EMPTY)
6126     {
6127       DrawLevelElement(x, y, Back[x][y]);
6128       DrawGraphicThruMask(SCREENX(x), SCREENY(y), graphic, frame);
6129     }
6130     else if (IS_WALKABLE_UNDER(Back[x][y]))
6131     {
6132       DrawLevelGraphic(x, y, graphic, frame);
6133       DrawLevelElementThruMask(x, y, Back[x][y]);
6134     }
6135     else if (!IS_WALKABLE_INSIDE(Back[x][y]))
6136       DrawLevelGraphic(x, y, graphic, frame);
6137   }
6138 }
6139
6140 static void DynaExplode(int ex, int ey)
6141 {
6142   int i, j;
6143   int dynabomb_element = Tile[ex][ey];
6144   int dynabomb_size = 1;
6145   boolean dynabomb_xl = FALSE;
6146   struct PlayerInfo *player;
6147   struct XY *xy = xy_topdown;
6148
6149   if (IS_ACTIVE_BOMB(dynabomb_element))
6150   {
6151     player = &stored_player[dynabomb_element - EL_DYNABOMB_PLAYER_1_ACTIVE];
6152     dynabomb_size = player->dynabomb_size;
6153     dynabomb_xl = player->dynabomb_xl;
6154     player->dynabombs_left++;
6155   }
6156
6157   Explode(ex, ey, EX_PHASE_START, EX_TYPE_CENTER);
6158
6159   for (i = 0; i < NUM_DIRECTIONS; i++)
6160   {
6161     for (j = 1; j <= dynabomb_size; j++)
6162     {
6163       int x = ex + j * xy[i].x;
6164       int y = ey + j * xy[i].y;
6165       int element;
6166
6167       if (!IN_LEV_FIELD(x, y) || IS_INDESTRUCTIBLE(Tile[x][y]))
6168         break;
6169
6170       element = Tile[x][y];
6171
6172       // do not restart explosions of fields with active bombs
6173       if (element == EL_EXPLOSION && IS_ACTIVE_BOMB(Store2[x][y]))
6174         continue;
6175
6176       Explode(x, y, EX_PHASE_START, EX_TYPE_BORDER);
6177
6178       if (element != EL_EMPTY && element != EL_EXPLOSION &&
6179           !IS_DIGGABLE(element) && !dynabomb_xl)
6180         break;
6181     }
6182   }
6183 }
6184
6185 void Bang(int x, int y)
6186 {
6187   int element = MovingOrBlocked2Element(x, y);
6188   int explosion_type = EX_TYPE_NORMAL;
6189
6190   if (IS_PLAYER(x, y) && !PLAYER_EXPLOSION_PROTECTED(x, y))
6191   {
6192     struct PlayerInfo *player = PLAYERINFO(x, y);
6193
6194     element = Tile[x][y] = player->initial_element;
6195
6196     if (level.use_explosion_element[player->index_nr])
6197     {
6198       int explosion_element = level.explosion_element[player->index_nr];
6199
6200       if (element_info[explosion_element].explosion_type == EXPLODES_CROSS)
6201         explosion_type = EX_TYPE_CROSS;
6202       else if (element_info[explosion_element].explosion_type == EXPLODES_1X1)
6203         explosion_type = EX_TYPE_CENTER;
6204     }
6205   }
6206
6207   switch (element)
6208   {
6209     case EL_BUG:
6210     case EL_SPACESHIP:
6211     case EL_BD_BUTTERFLY:
6212     case EL_BD_FIREFLY:
6213     case EL_YAMYAM:
6214     case EL_DARK_YAMYAM:
6215     case EL_ROBOT:
6216     case EL_PACMAN:
6217     case EL_MOLE:
6218       RaiseScoreElement(element);
6219       break;
6220
6221     case EL_DYNABOMB_PLAYER_1_ACTIVE:
6222     case EL_DYNABOMB_PLAYER_2_ACTIVE:
6223     case EL_DYNABOMB_PLAYER_3_ACTIVE:
6224     case EL_DYNABOMB_PLAYER_4_ACTIVE:
6225     case EL_DYNABOMB_INCREASE_NUMBER:
6226     case EL_DYNABOMB_INCREASE_SIZE:
6227     case EL_DYNABOMB_INCREASE_POWER:
6228       explosion_type = EX_TYPE_DYNA;
6229       break;
6230
6231     case EL_DC_LANDMINE:
6232       explosion_type = EX_TYPE_CENTER;
6233       break;
6234
6235     case EL_PENGUIN:
6236     case EL_LAMP:
6237     case EL_LAMP_ACTIVE:
6238     case EL_AMOEBA_TO_DIAMOND:
6239       if (!IS_PLAYER(x, y))     // penguin and player may be at same field
6240         explosion_type = EX_TYPE_CENTER;
6241       break;
6242
6243     default:
6244       if (element_info[element].explosion_type == EXPLODES_CROSS)
6245         explosion_type = EX_TYPE_CROSS;
6246       else if (element_info[element].explosion_type == EXPLODES_1X1)
6247         explosion_type = EX_TYPE_CENTER;
6248       break;
6249   }
6250
6251   if (explosion_type == EX_TYPE_DYNA)
6252     DynaExplode(x, y);
6253   else
6254     Explode(x, y, EX_PHASE_START, explosion_type);
6255
6256   CheckTriggeredElementChange(x, y, element, CE_EXPLOSION_OF_X);
6257 }
6258
6259 static void SplashAcid(int x, int y)
6260 {
6261   if (IN_LEV_FIELD(x - 1, y - 1) && IS_FREE(x - 1, y - 1) &&
6262       (!IN_LEV_FIELD(x - 1, y - 2) ||
6263        !CAN_FALL(MovingOrBlocked2Element(x - 1, y - 2))))
6264     Tile[x - 1][y - 1] = EL_ACID_SPLASH_LEFT;
6265
6266   if (IN_LEV_FIELD(x + 1, y - 1) && IS_FREE(x + 1, y - 1) &&
6267       (!IN_LEV_FIELD(x + 1, y - 2) ||
6268        !CAN_FALL(MovingOrBlocked2Element(x + 1, y - 2))))
6269     Tile[x + 1][y - 1] = EL_ACID_SPLASH_RIGHT;
6270
6271   PlayLevelSound(x, y, SND_ACID_SPLASHING);
6272 }
6273
6274 static void InitBeltMovement(void)
6275 {
6276   static int belt_base_element[4] =
6277   {
6278     EL_CONVEYOR_BELT_1_LEFT,
6279     EL_CONVEYOR_BELT_2_LEFT,
6280     EL_CONVEYOR_BELT_3_LEFT,
6281     EL_CONVEYOR_BELT_4_LEFT
6282   };
6283   static int belt_base_active_element[4] =
6284   {
6285     EL_CONVEYOR_BELT_1_LEFT_ACTIVE,
6286     EL_CONVEYOR_BELT_2_LEFT_ACTIVE,
6287     EL_CONVEYOR_BELT_3_LEFT_ACTIVE,
6288     EL_CONVEYOR_BELT_4_LEFT_ACTIVE
6289   };
6290
6291   int x, y, i, j;
6292
6293   // set frame order for belt animation graphic according to belt direction
6294   for (i = 0; i < NUM_BELTS; i++)
6295   {
6296     int belt_nr = i;
6297
6298     for (j = 0; j < NUM_BELT_PARTS; j++)
6299     {
6300       int element = belt_base_active_element[belt_nr] + j;
6301       int graphic_1 = el2img(element);
6302       int graphic_2 = el2panelimg(element);
6303
6304       if (game.belt_dir[i] == MV_LEFT)
6305       {
6306         graphic_info[graphic_1].anim_mode &= ~ANIM_REVERSE;
6307         graphic_info[graphic_2].anim_mode &= ~ANIM_REVERSE;
6308       }
6309       else
6310       {
6311         graphic_info[graphic_1].anim_mode |=  ANIM_REVERSE;
6312         graphic_info[graphic_2].anim_mode |=  ANIM_REVERSE;
6313       }
6314     }
6315   }
6316
6317   SCAN_PLAYFIELD(x, y)
6318   {
6319     int element = Tile[x][y];
6320
6321     for (i = 0; i < NUM_BELTS; i++)
6322     {
6323       if (IS_BELT(element) && game.belt_dir[i] != MV_NONE)
6324       {
6325         int e_belt_nr = getBeltNrFromBeltElement(element);
6326         int belt_nr = i;
6327
6328         if (e_belt_nr == belt_nr)
6329         {
6330           int belt_part = Tile[x][y] - belt_base_element[belt_nr];
6331
6332           Tile[x][y] = belt_base_active_element[belt_nr] + belt_part;
6333         }
6334       }
6335     }
6336   }
6337 }
6338
6339 static void ToggleBeltSwitch(int x, int y)
6340 {
6341   static int belt_base_element[4] =
6342   {
6343     EL_CONVEYOR_BELT_1_LEFT,
6344     EL_CONVEYOR_BELT_2_LEFT,
6345     EL_CONVEYOR_BELT_3_LEFT,
6346     EL_CONVEYOR_BELT_4_LEFT
6347   };
6348   static int belt_base_active_element[4] =
6349   {
6350     EL_CONVEYOR_BELT_1_LEFT_ACTIVE,
6351     EL_CONVEYOR_BELT_2_LEFT_ACTIVE,
6352     EL_CONVEYOR_BELT_3_LEFT_ACTIVE,
6353     EL_CONVEYOR_BELT_4_LEFT_ACTIVE
6354   };
6355   static int belt_base_switch_element[4] =
6356   {
6357     EL_CONVEYOR_BELT_1_SWITCH_LEFT,
6358     EL_CONVEYOR_BELT_2_SWITCH_LEFT,
6359     EL_CONVEYOR_BELT_3_SWITCH_LEFT,
6360     EL_CONVEYOR_BELT_4_SWITCH_LEFT
6361   };
6362   static int belt_move_dir[4] =
6363   {
6364     MV_LEFT,
6365     MV_NONE,
6366     MV_RIGHT,
6367     MV_NONE,
6368   };
6369
6370   int element = Tile[x][y];
6371   int belt_nr = getBeltNrFromBeltSwitchElement(element);
6372   int belt_dir_nr = (game.belt_dir_nr[belt_nr] + 1) % 4;
6373   int belt_dir = belt_move_dir[belt_dir_nr];
6374   int xx, yy, i;
6375
6376   if (!IS_BELT_SWITCH(element))
6377     return;
6378
6379   game.belt_dir_nr[belt_nr] = belt_dir_nr;
6380   game.belt_dir[belt_nr] = belt_dir;
6381
6382   if (belt_dir_nr == 3)
6383     belt_dir_nr = 1;
6384
6385   // set frame order for belt animation graphic according to belt direction
6386   for (i = 0; i < NUM_BELT_PARTS; i++)
6387   {
6388     int element = belt_base_active_element[belt_nr] + i;
6389     int graphic_1 = el2img(element);
6390     int graphic_2 = el2panelimg(element);
6391
6392     if (belt_dir == MV_LEFT)
6393     {
6394       graphic_info[graphic_1].anim_mode &= ~ANIM_REVERSE;
6395       graphic_info[graphic_2].anim_mode &= ~ANIM_REVERSE;
6396     }
6397     else
6398     {
6399       graphic_info[graphic_1].anim_mode |=  ANIM_REVERSE;
6400       graphic_info[graphic_2].anim_mode |=  ANIM_REVERSE;
6401     }
6402   }
6403
6404   SCAN_PLAYFIELD(xx, yy)
6405   {
6406     int element = Tile[xx][yy];
6407
6408     if (IS_BELT_SWITCH(element))
6409     {
6410       int e_belt_nr = getBeltNrFromBeltSwitchElement(element);
6411
6412       if (e_belt_nr == belt_nr)
6413       {
6414         Tile[xx][yy] = belt_base_switch_element[belt_nr] + belt_dir_nr;
6415         TEST_DrawLevelField(xx, yy);
6416       }
6417     }
6418     else if (IS_BELT(element) && belt_dir != MV_NONE)
6419     {
6420       int e_belt_nr = getBeltNrFromBeltElement(element);
6421
6422       if (e_belt_nr == belt_nr)
6423       {
6424         int belt_part = Tile[xx][yy] - belt_base_element[belt_nr];
6425
6426         Tile[xx][yy] = belt_base_active_element[belt_nr] + belt_part;
6427         TEST_DrawLevelField(xx, yy);
6428       }
6429     }
6430     else if (IS_BELT_ACTIVE(element) && belt_dir == MV_NONE)
6431     {
6432       int e_belt_nr = getBeltNrFromBeltActiveElement(element);
6433
6434       if (e_belt_nr == belt_nr)
6435       {
6436         int belt_part = Tile[xx][yy] - belt_base_active_element[belt_nr];
6437
6438         Tile[xx][yy] = belt_base_element[belt_nr] + belt_part;
6439         TEST_DrawLevelField(xx, yy);
6440       }
6441     }
6442   }
6443 }
6444
6445 static void ToggleSwitchgateSwitch(void)
6446 {
6447   int xx, yy;
6448
6449   game.switchgate_pos = !game.switchgate_pos;
6450
6451   SCAN_PLAYFIELD(xx, yy)
6452   {
6453     int element = Tile[xx][yy];
6454
6455     if (element == EL_SWITCHGATE_SWITCH_UP)
6456     {
6457       Tile[xx][yy] = EL_SWITCHGATE_SWITCH_DOWN;
6458       TEST_DrawLevelField(xx, yy);
6459     }
6460     else if (element == EL_SWITCHGATE_SWITCH_DOWN)
6461     {
6462       Tile[xx][yy] = EL_SWITCHGATE_SWITCH_UP;
6463       TEST_DrawLevelField(xx, yy);
6464     }
6465     else if (element == EL_DC_SWITCHGATE_SWITCH_UP)
6466     {
6467       Tile[xx][yy] = EL_DC_SWITCHGATE_SWITCH_DOWN;
6468       TEST_DrawLevelField(xx, yy);
6469     }
6470     else if (element == EL_DC_SWITCHGATE_SWITCH_DOWN)
6471     {
6472       Tile[xx][yy] = EL_DC_SWITCHGATE_SWITCH_UP;
6473       TEST_DrawLevelField(xx, yy);
6474     }
6475     else if (element == EL_SWITCHGATE_OPEN ||
6476              element == EL_SWITCHGATE_OPENING)
6477     {
6478       Tile[xx][yy] = EL_SWITCHGATE_CLOSING;
6479
6480       PlayLevelSoundAction(xx, yy, ACTION_CLOSING);
6481     }
6482     else if (element == EL_SWITCHGATE_CLOSED ||
6483              element == EL_SWITCHGATE_CLOSING)
6484     {
6485       Tile[xx][yy] = EL_SWITCHGATE_OPENING;
6486
6487       PlayLevelSoundAction(xx, yy, ACTION_OPENING);
6488     }
6489   }
6490 }
6491
6492 static int getInvisibleActiveFromInvisibleElement(int element)
6493 {
6494   return (element == EL_INVISIBLE_STEELWALL ? EL_INVISIBLE_STEELWALL_ACTIVE :
6495           element == EL_INVISIBLE_WALL      ? EL_INVISIBLE_WALL_ACTIVE :
6496           element == EL_INVISIBLE_SAND      ? EL_INVISIBLE_SAND_ACTIVE :
6497           element);
6498 }
6499
6500 static int getInvisibleFromInvisibleActiveElement(int element)
6501 {
6502   return (element == EL_INVISIBLE_STEELWALL_ACTIVE ? EL_INVISIBLE_STEELWALL :
6503           element == EL_INVISIBLE_WALL_ACTIVE      ? EL_INVISIBLE_WALL :
6504           element == EL_INVISIBLE_SAND_ACTIVE      ? EL_INVISIBLE_SAND :
6505           element);
6506 }
6507
6508 static void RedrawAllLightSwitchesAndInvisibleElements(void)
6509 {
6510   int x, y;
6511
6512   SCAN_PLAYFIELD(x, y)
6513   {
6514     int element = Tile[x][y];
6515
6516     if (element == EL_LIGHT_SWITCH &&
6517         game.light_time_left > 0)
6518     {
6519       Tile[x][y] = EL_LIGHT_SWITCH_ACTIVE;
6520       TEST_DrawLevelField(x, y);
6521     }
6522     else if (element == EL_LIGHT_SWITCH_ACTIVE &&
6523              game.light_time_left == 0)
6524     {
6525       Tile[x][y] = EL_LIGHT_SWITCH;
6526       TEST_DrawLevelField(x, y);
6527     }
6528     else if (element == EL_EMC_DRIPPER &&
6529              game.light_time_left > 0)
6530     {
6531       Tile[x][y] = EL_EMC_DRIPPER_ACTIVE;
6532       TEST_DrawLevelField(x, y);
6533     }
6534     else if (element == EL_EMC_DRIPPER_ACTIVE &&
6535              game.light_time_left == 0)
6536     {
6537       Tile[x][y] = EL_EMC_DRIPPER;
6538       TEST_DrawLevelField(x, y);
6539     }
6540     else if (element == EL_INVISIBLE_STEELWALL ||
6541              element == EL_INVISIBLE_WALL ||
6542              element == EL_INVISIBLE_SAND)
6543     {
6544       if (game.light_time_left > 0)
6545         Tile[x][y] = getInvisibleActiveFromInvisibleElement(element);
6546
6547       TEST_DrawLevelField(x, y);
6548
6549       // uncrumble neighbour fields, if needed
6550       if (element == EL_INVISIBLE_SAND)
6551         TEST_DrawLevelFieldCrumbledNeighbours(x, y);
6552     }
6553     else if (element == EL_INVISIBLE_STEELWALL_ACTIVE ||
6554              element == EL_INVISIBLE_WALL_ACTIVE ||
6555              element == EL_INVISIBLE_SAND_ACTIVE)
6556     {
6557       if (game.light_time_left == 0)
6558         Tile[x][y] = getInvisibleFromInvisibleActiveElement(element);
6559
6560       TEST_DrawLevelField(x, y);
6561
6562       // re-crumble neighbour fields, if needed
6563       if (element == EL_INVISIBLE_SAND)
6564         TEST_DrawLevelFieldCrumbledNeighbours(x, y);
6565     }
6566   }
6567 }
6568
6569 static void RedrawAllInvisibleElementsForLenses(void)
6570 {
6571   int x, y;
6572
6573   SCAN_PLAYFIELD(x, y)
6574   {
6575     int element = Tile[x][y];
6576
6577     if (element == EL_EMC_DRIPPER &&
6578         game.lenses_time_left > 0)
6579     {
6580       Tile[x][y] = EL_EMC_DRIPPER_ACTIVE;
6581       TEST_DrawLevelField(x, y);
6582     }
6583     else if (element == EL_EMC_DRIPPER_ACTIVE &&
6584              game.lenses_time_left == 0)
6585     {
6586       Tile[x][y] = EL_EMC_DRIPPER;
6587       TEST_DrawLevelField(x, y);
6588     }
6589     else if (element == EL_INVISIBLE_STEELWALL ||
6590              element == EL_INVISIBLE_WALL ||
6591              element == EL_INVISIBLE_SAND)
6592     {
6593       if (game.lenses_time_left > 0)
6594         Tile[x][y] = getInvisibleActiveFromInvisibleElement(element);
6595
6596       TEST_DrawLevelField(x, y);
6597
6598       // uncrumble neighbour fields, if needed
6599       if (element == EL_INVISIBLE_SAND)
6600         TEST_DrawLevelFieldCrumbledNeighbours(x, y);
6601     }
6602     else if (element == EL_INVISIBLE_STEELWALL_ACTIVE ||
6603              element == EL_INVISIBLE_WALL_ACTIVE ||
6604              element == EL_INVISIBLE_SAND_ACTIVE)
6605     {
6606       if (game.lenses_time_left == 0)
6607         Tile[x][y] = getInvisibleFromInvisibleActiveElement(element);
6608
6609       TEST_DrawLevelField(x, y);
6610
6611       // re-crumble neighbour fields, if needed
6612       if (element == EL_INVISIBLE_SAND)
6613         TEST_DrawLevelFieldCrumbledNeighbours(x, y);
6614     }
6615   }
6616 }
6617
6618 static void RedrawAllInvisibleElementsForMagnifier(void)
6619 {
6620   int x, y;
6621
6622   SCAN_PLAYFIELD(x, y)
6623   {
6624     int element = Tile[x][y];
6625
6626     if (element == EL_EMC_FAKE_GRASS &&
6627         game.magnify_time_left > 0)
6628     {
6629       Tile[x][y] = EL_EMC_FAKE_GRASS_ACTIVE;
6630       TEST_DrawLevelField(x, y);
6631     }
6632     else if (element == EL_EMC_FAKE_GRASS_ACTIVE &&
6633              game.magnify_time_left == 0)
6634     {
6635       Tile[x][y] = EL_EMC_FAKE_GRASS;
6636       TEST_DrawLevelField(x, y);
6637     }
6638     else if (IS_GATE_GRAY(element) &&
6639              game.magnify_time_left > 0)
6640     {
6641       Tile[x][y] = (IS_RND_GATE_GRAY(element) ?
6642                     element - EL_GATE_1_GRAY + EL_GATE_1_GRAY_ACTIVE :
6643                     IS_EM_GATE_GRAY(element) ?
6644                     element - EL_EM_GATE_1_GRAY + EL_EM_GATE_1_GRAY_ACTIVE :
6645                     IS_EMC_GATE_GRAY(element) ?
6646                     element - EL_EMC_GATE_5_GRAY + EL_EMC_GATE_5_GRAY_ACTIVE :
6647                     IS_DC_GATE_GRAY(element) ?
6648                     EL_DC_GATE_WHITE_GRAY_ACTIVE :
6649                     element);
6650       TEST_DrawLevelField(x, y);
6651     }
6652     else if (IS_GATE_GRAY_ACTIVE(element) &&
6653              game.magnify_time_left == 0)
6654     {
6655       Tile[x][y] = (IS_RND_GATE_GRAY_ACTIVE(element) ?
6656                     element - EL_GATE_1_GRAY_ACTIVE + EL_GATE_1_GRAY :
6657                     IS_EM_GATE_GRAY_ACTIVE(element) ?
6658                     element - EL_EM_GATE_1_GRAY_ACTIVE + EL_EM_GATE_1_GRAY :
6659                     IS_EMC_GATE_GRAY_ACTIVE(element) ?
6660                     element - EL_EMC_GATE_5_GRAY_ACTIVE + EL_EMC_GATE_5_GRAY :
6661                     IS_DC_GATE_GRAY_ACTIVE(element) ?
6662                     EL_DC_GATE_WHITE_GRAY :
6663                     element);
6664       TEST_DrawLevelField(x, y);
6665     }
6666   }
6667 }
6668
6669 static void ToggleLightSwitch(int x, int y)
6670 {
6671   int element = Tile[x][y];
6672
6673   game.light_time_left =
6674     (element == EL_LIGHT_SWITCH ?
6675      level.time_light * FRAMES_PER_SECOND : 0);
6676
6677   RedrawAllLightSwitchesAndInvisibleElements();
6678 }
6679
6680 static void ActivateTimegateSwitch(int x, int y)
6681 {
6682   int xx, yy;
6683
6684   game.timegate_time_left = level.time_timegate * FRAMES_PER_SECOND;
6685
6686   SCAN_PLAYFIELD(xx, yy)
6687   {
6688     int element = Tile[xx][yy];
6689
6690     if (element == EL_TIMEGATE_CLOSED ||
6691         element == EL_TIMEGATE_CLOSING)
6692     {
6693       Tile[xx][yy] = EL_TIMEGATE_OPENING;
6694       PlayLevelSound(xx, yy, SND_CLASS_TIMEGATE_OPENING);
6695     }
6696
6697     /*
6698     else if (element == EL_TIMEGATE_SWITCH_ACTIVE)
6699     {
6700       Tile[xx][yy] = EL_TIMEGATE_SWITCH;
6701       TEST_DrawLevelField(xx, yy);
6702     }
6703     */
6704
6705   }
6706
6707   Tile[x][y] = (Tile[x][y] == EL_TIMEGATE_SWITCH ? EL_TIMEGATE_SWITCH_ACTIVE :
6708                 EL_DC_TIMEGATE_SWITCH_ACTIVE);
6709 }
6710
6711 static void Impact(int x, int y)
6712 {
6713   boolean last_line = (y == lev_fieldy - 1);
6714   boolean object_hit = FALSE;
6715   boolean impact = (last_line || object_hit);
6716   int element = Tile[x][y];
6717   int smashed = EL_STEELWALL;
6718
6719   if (!last_line)       // check if element below was hit
6720   {
6721     if (Tile[x][y + 1] == EL_PLAYER_IS_LEAVING)
6722       return;
6723
6724     object_hit = (!IS_FREE(x, y + 1) && (!IS_MOVING(x, y + 1) ||
6725                                          MovDir[x][y + 1] != MV_DOWN ||
6726                                          MovPos[x][y + 1] <= TILEY / 2));
6727
6728     // do not smash moving elements that left the smashed field in time
6729     if (game.engine_version >= VERSION_IDENT(2,2,0,7) && IS_MOVING(x, y + 1) &&
6730         ABS(MovPos[x][y + 1] + getElementMoveStepsize(x, y + 1)) >= TILEX)
6731       object_hit = FALSE;
6732
6733 #if USE_QUICKSAND_IMPACT_BUGFIX
6734     if (Tile[x][y + 1] == EL_QUICKSAND_EMPTYING && object_hit == FALSE)
6735     {
6736       RemoveMovingField(x, y + 1);
6737       Tile[x][y + 1] = EL_QUICKSAND_EMPTY;
6738       Tile[x][y + 2] = EL_ROCK;
6739       TEST_DrawLevelField(x, y + 2);
6740
6741       object_hit = TRUE;
6742     }
6743
6744     if (Tile[x][y + 1] == EL_QUICKSAND_FAST_EMPTYING && object_hit == FALSE)
6745     {
6746       RemoveMovingField(x, y + 1);
6747       Tile[x][y + 1] = EL_QUICKSAND_FAST_EMPTY;
6748       Tile[x][y + 2] = EL_ROCK;
6749       TEST_DrawLevelField(x, y + 2);
6750
6751       object_hit = TRUE;
6752     }
6753 #endif
6754
6755     if (object_hit)
6756       smashed = MovingOrBlocked2Element(x, y + 1);
6757
6758     impact = (last_line || object_hit);
6759   }
6760
6761   if (!last_line && smashed == EL_ACID) // element falls into acid
6762   {
6763     SplashAcid(x, y + 1);
6764     return;
6765   }
6766
6767   // !!! not sufficient for all cases -- see EL_PEARL below !!!
6768   // only reset graphic animation if graphic really changes after impact
6769   if (impact &&
6770       el_act_dir2img(element, GfxAction[x][y], MV_DOWN) != el2img(element))
6771   {
6772     ResetGfxAnimation(x, y);
6773     TEST_DrawLevelField(x, y);
6774   }
6775
6776   if (impact && CAN_EXPLODE_IMPACT(element))
6777   {
6778     Bang(x, y);
6779     return;
6780   }
6781   else if (impact && element == EL_PEARL &&
6782            smashed != EL_DC_MAGIC_WALL && smashed != EL_DC_MAGIC_WALL_ACTIVE)
6783   {
6784     ResetGfxAnimation(x, y);
6785
6786     Tile[x][y] = EL_PEARL_BREAKING;
6787     PlayLevelSound(x, y, SND_PEARL_BREAKING);
6788     return;
6789   }
6790   else if (impact && CheckElementChange(x, y, element, smashed, CE_IMPACT))
6791   {
6792     PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
6793
6794     return;
6795   }
6796
6797   if (impact && element == EL_AMOEBA_DROP)
6798   {
6799     if (object_hit && IS_PLAYER(x, y + 1))
6800       KillPlayerUnlessEnemyProtected(x, y + 1);
6801     else if (object_hit && smashed == EL_PENGUIN)
6802       Bang(x, y + 1);
6803     else
6804     {
6805       Tile[x][y] = EL_AMOEBA_GROWING;
6806       Store[x][y] = EL_AMOEBA_WET;
6807
6808       ResetRandomAnimationValue(x, y);
6809     }
6810     return;
6811   }
6812
6813   if (object_hit)               // check which object was hit
6814   {
6815     if ((CAN_PASS_MAGIC_WALL(element) &&
6816          (smashed == EL_MAGIC_WALL ||
6817           smashed == EL_BD_MAGIC_WALL)) ||
6818         (CAN_PASS_DC_MAGIC_WALL(element) &&
6819          smashed == EL_DC_MAGIC_WALL))
6820     {
6821       int xx, yy;
6822       int activated_magic_wall =
6823         (smashed == EL_MAGIC_WALL ? EL_MAGIC_WALL_ACTIVE :
6824          smashed == EL_BD_MAGIC_WALL ? EL_BD_MAGIC_WALL_ACTIVE :
6825          EL_DC_MAGIC_WALL_ACTIVE);
6826
6827       // activate magic wall / mill
6828       SCAN_PLAYFIELD(xx, yy)
6829       {
6830         if (Tile[xx][yy] == smashed)
6831           Tile[xx][yy] = activated_magic_wall;
6832       }
6833
6834       game.magic_wall_time_left = level.time_magic_wall * FRAMES_PER_SECOND;
6835       game.magic_wall_active = TRUE;
6836
6837       PlayLevelSound(x, y, (smashed == EL_MAGIC_WALL ?
6838                             SND_MAGIC_WALL_ACTIVATING :
6839                             smashed == EL_BD_MAGIC_WALL ?
6840                             SND_BD_MAGIC_WALL_ACTIVATING :
6841                             SND_DC_MAGIC_WALL_ACTIVATING));
6842     }
6843
6844     if (IS_PLAYER(x, y + 1))
6845     {
6846       if (CAN_SMASH_PLAYER(element))
6847       {
6848         KillPlayerUnlessEnemyProtected(x, y + 1);
6849         return;
6850       }
6851     }
6852     else if (smashed == EL_PENGUIN)
6853     {
6854       if (CAN_SMASH_PLAYER(element))
6855       {
6856         Bang(x, y + 1);
6857         return;
6858       }
6859     }
6860     else if (element == EL_BD_DIAMOND)
6861     {
6862       if (IS_CLASSIC_ENEMY(smashed) && IS_BD_ELEMENT(smashed))
6863       {
6864         Bang(x, y + 1);
6865         return;
6866       }
6867     }
6868     else if (((element == EL_SP_INFOTRON ||
6869                element == EL_SP_ZONK) &&
6870               (smashed == EL_SP_SNIKSNAK ||
6871                smashed == EL_SP_ELECTRON ||
6872                smashed == EL_SP_DISK_ORANGE)) ||
6873              (element == EL_SP_INFOTRON &&
6874               smashed == EL_SP_DISK_YELLOW))
6875     {
6876       Bang(x, y + 1);
6877       return;
6878     }
6879     else if (CAN_SMASH_EVERYTHING(element))
6880     {
6881       if (IS_CLASSIC_ENEMY(smashed) ||
6882           CAN_EXPLODE_SMASHED(smashed))
6883       {
6884         Bang(x, y + 1);
6885         return;
6886       }
6887       else if (!IS_MOVING(x, y + 1) && !IS_BLOCKED(x, y + 1))
6888       {
6889         if (smashed == EL_LAMP ||
6890             smashed == EL_LAMP_ACTIVE)
6891         {
6892           Bang(x, y + 1);
6893           return;
6894         }
6895         else if (smashed == EL_NUT)
6896         {
6897           Tile[x][y + 1] = EL_NUT_BREAKING;
6898           PlayLevelSound(x, y, SND_NUT_BREAKING);
6899           RaiseScoreElement(EL_NUT);
6900           return;
6901         }
6902         else if (smashed == EL_PEARL)
6903         {
6904           ResetGfxAnimation(x, y);
6905
6906           Tile[x][y + 1] = EL_PEARL_BREAKING;
6907           PlayLevelSound(x, y, SND_PEARL_BREAKING);
6908           return;
6909         }
6910         else if (smashed == EL_DIAMOND)
6911         {
6912           Tile[x][y + 1] = EL_DIAMOND_BREAKING;
6913           PlayLevelSound(x, y, SND_DIAMOND_BREAKING);
6914           return;
6915         }
6916         else if (IS_BELT_SWITCH(smashed))
6917         {
6918           ToggleBeltSwitch(x, y + 1);
6919         }
6920         else if (smashed == EL_SWITCHGATE_SWITCH_UP ||
6921                  smashed == EL_SWITCHGATE_SWITCH_DOWN ||
6922                  smashed == EL_DC_SWITCHGATE_SWITCH_UP ||
6923                  smashed == EL_DC_SWITCHGATE_SWITCH_DOWN)
6924         {
6925           ToggleSwitchgateSwitch();
6926         }
6927         else if (smashed == EL_LIGHT_SWITCH ||
6928                  smashed == EL_LIGHT_SWITCH_ACTIVE)
6929         {
6930           ToggleLightSwitch(x, y + 1);
6931         }
6932         else
6933         {
6934           CheckElementChange(x, y + 1, smashed, element, CE_SMASHED);
6935
6936           CheckElementChangeBySide(x, y + 1, smashed, element,
6937                                    CE_SWITCHED, CH_SIDE_TOP);
6938           CheckTriggeredElementChangeBySide(x, y + 1, smashed, CE_SWITCH_OF_X,
6939                                             CH_SIDE_TOP);
6940         }
6941       }
6942       else
6943       {
6944         CheckElementChange(x, y + 1, smashed, element, CE_SMASHED);
6945       }
6946     }
6947   }
6948
6949   // play sound of magic wall / mill
6950   if (!last_line &&
6951       (Tile[x][y + 1] == EL_MAGIC_WALL_ACTIVE ||
6952        Tile[x][y + 1] == EL_BD_MAGIC_WALL_ACTIVE ||
6953        Tile[x][y + 1] == EL_DC_MAGIC_WALL_ACTIVE))
6954   {
6955     if (Tile[x][y + 1] == EL_MAGIC_WALL_ACTIVE)
6956       PlayLevelSound(x, y, SND_MAGIC_WALL_FILLING);
6957     else if (Tile[x][y + 1] == EL_BD_MAGIC_WALL_ACTIVE)
6958       PlayLevelSound(x, y, SND_BD_MAGIC_WALL_FILLING);
6959     else if (Tile[x][y + 1] == EL_DC_MAGIC_WALL_ACTIVE)
6960       PlayLevelSound(x, y, SND_DC_MAGIC_WALL_FILLING);
6961
6962     return;
6963   }
6964
6965   // play sound of object that hits the ground
6966   if (last_line || object_hit)
6967     PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
6968 }
6969
6970 static void TurnRoundExt(int x, int y)
6971 {
6972   static struct
6973   {
6974     int dx, dy;
6975   } move_xy[] =
6976   {
6977     {  0,  0 },
6978     { -1,  0 },
6979     { +1,  0 },
6980     {  0,  0 },
6981     {  0, -1 },
6982     {  0,  0 }, { 0, 0 }, { 0, 0 },
6983     {  0, +1 }
6984   };
6985   static struct
6986   {
6987     int left, right, back;
6988   } turn[] =
6989   {
6990     { 0,        0,              0        },
6991     { MV_DOWN,  MV_UP,          MV_RIGHT },
6992     { MV_UP,    MV_DOWN,        MV_LEFT  },
6993     { 0,        0,              0        },
6994     { MV_LEFT,  MV_RIGHT,       MV_DOWN  },
6995     { 0,        0,              0        },
6996     { 0,        0,              0        },
6997     { 0,        0,              0        },
6998     { MV_RIGHT, MV_LEFT,        MV_UP    }
6999   };
7000
7001   int element = Tile[x][y];
7002   int move_pattern = element_info[element].move_pattern;
7003
7004   int old_move_dir = MovDir[x][y];
7005   int left_dir  = turn[old_move_dir].left;
7006   int right_dir = turn[old_move_dir].right;
7007   int back_dir  = turn[old_move_dir].back;
7008
7009   int left_dx  = move_xy[left_dir].dx,     left_dy  = move_xy[left_dir].dy;
7010   int right_dx = move_xy[right_dir].dx,    right_dy = move_xy[right_dir].dy;
7011   int move_dx  = move_xy[old_move_dir].dx, move_dy  = move_xy[old_move_dir].dy;
7012   int back_dx  = move_xy[back_dir].dx,     back_dy  = move_xy[back_dir].dy;
7013
7014   int left_x  = x + left_dx,  left_y  = y + left_dy;
7015   int right_x = x + right_dx, right_y = y + right_dy;
7016   int move_x  = x + move_dx,  move_y  = y + move_dy;
7017
7018   int xx, yy;
7019
7020   if (element == EL_BUG || element == EL_BD_BUTTERFLY)
7021   {
7022     TestIfBadThingTouchesOtherBadThing(x, y);
7023
7024     if (ENEMY_CAN_ENTER_FIELD(element, right_x, right_y))
7025       MovDir[x][y] = right_dir;
7026     else if (!ENEMY_CAN_ENTER_FIELD(element, move_x, move_y))
7027       MovDir[x][y] = left_dir;
7028
7029     if (element == EL_BUG && MovDir[x][y] != old_move_dir)
7030       MovDelay[x][y] = 9;
7031     else if (element == EL_BD_BUTTERFLY)     // && MovDir[x][y] == left_dir)
7032       MovDelay[x][y] = 1;
7033   }
7034   else if (element == EL_SPACESHIP || element == EL_BD_FIREFLY)
7035   {
7036     TestIfBadThingTouchesOtherBadThing(x, y);
7037
7038     if (ENEMY_CAN_ENTER_FIELD(element, left_x, left_y))
7039       MovDir[x][y] = left_dir;
7040     else if (!ENEMY_CAN_ENTER_FIELD(element, move_x, move_y))
7041       MovDir[x][y] = right_dir;
7042
7043     if (element == EL_SPACESHIP && MovDir[x][y] != old_move_dir)
7044       MovDelay[x][y] = 9;
7045     else if (element == EL_BD_FIREFLY)      // && MovDir[x][y] == right_dir)
7046       MovDelay[x][y] = 1;
7047   }
7048   else if (element == EL_SP_SNIKSNAK || element == EL_SP_ELECTRON)
7049   {
7050     TestIfBadThingTouchesOtherBadThing(x, y);
7051
7052     if (ELEMENT_CAN_ENTER_FIELD_BASE_4(element, left_x, left_y, 0))
7053       MovDir[x][y] = left_dir;
7054     else if (!ELEMENT_CAN_ENTER_FIELD_BASE_4(element, move_x, move_y, 0))
7055       MovDir[x][y] = right_dir;
7056
7057     if (MovDir[x][y] != old_move_dir)
7058       MovDelay[x][y] = 9;
7059   }
7060   else if (element == EL_YAMYAM)
7061   {
7062     boolean can_turn_left  = YAMYAM_CAN_ENTER_FIELD(element, left_x, left_y);
7063     boolean can_turn_right = YAMYAM_CAN_ENTER_FIELD(element, right_x, right_y);
7064
7065     if (can_turn_left && can_turn_right)
7066       MovDir[x][y] = (RND(3) ? (RND(2) ? left_dir : right_dir) : back_dir);
7067     else if (can_turn_left)
7068       MovDir[x][y] = (RND(2) ? left_dir : back_dir);
7069     else if (can_turn_right)
7070       MovDir[x][y] = (RND(2) ? right_dir : back_dir);
7071     else
7072       MovDir[x][y] = back_dir;
7073
7074     MovDelay[x][y] = 16 + 16 * RND(3);
7075   }
7076   else if (element == EL_DARK_YAMYAM)
7077   {
7078     boolean can_turn_left  = DARK_YAMYAM_CAN_ENTER_FIELD(element,
7079                                                          left_x, left_y);
7080     boolean can_turn_right = DARK_YAMYAM_CAN_ENTER_FIELD(element,
7081                                                          right_x, right_y);
7082
7083     if (can_turn_left && can_turn_right)
7084       MovDir[x][y] = (RND(3) ? (RND(2) ? left_dir : right_dir) : back_dir);
7085     else if (can_turn_left)
7086       MovDir[x][y] = (RND(2) ? left_dir : back_dir);
7087     else if (can_turn_right)
7088       MovDir[x][y] = (RND(2) ? right_dir : back_dir);
7089     else
7090       MovDir[x][y] = back_dir;
7091
7092     MovDelay[x][y] = 16 + 16 * RND(3);
7093   }
7094   else if (element == EL_PACMAN)
7095   {
7096     boolean can_turn_left  = PACMAN_CAN_ENTER_FIELD(element, left_x, left_y);
7097     boolean can_turn_right = PACMAN_CAN_ENTER_FIELD(element, right_x, right_y);
7098
7099     if (can_turn_left && can_turn_right)
7100       MovDir[x][y] = (RND(3) ? (RND(2) ? left_dir : right_dir) : back_dir);
7101     else if (can_turn_left)
7102       MovDir[x][y] = (RND(2) ? left_dir : back_dir);
7103     else if (can_turn_right)
7104       MovDir[x][y] = (RND(2) ? right_dir : back_dir);
7105     else
7106       MovDir[x][y] = back_dir;
7107
7108     MovDelay[x][y] = 6 + RND(40);
7109   }
7110   else if (element == EL_PIG)
7111   {
7112     boolean can_turn_left  = PIG_CAN_ENTER_FIELD(element, left_x, left_y);
7113     boolean can_turn_right = PIG_CAN_ENTER_FIELD(element, right_x, right_y);
7114     boolean can_move_on    = PIG_CAN_ENTER_FIELD(element, move_x, move_y);
7115     boolean should_turn_left, should_turn_right, should_move_on;
7116     int rnd_value = 24;
7117     int rnd = RND(rnd_value);
7118
7119     should_turn_left = (can_turn_left &&
7120                         (!can_move_on ||
7121                          IN_LEV_FIELD_AND_NOT_FREE(x + back_dx + left_dx,
7122                                                    y + back_dy + left_dy)));
7123     should_turn_right = (can_turn_right &&
7124                          (!can_move_on ||
7125                           IN_LEV_FIELD_AND_NOT_FREE(x + back_dx + right_dx,
7126                                                     y + back_dy + right_dy)));
7127     should_move_on = (can_move_on &&
7128                       (!can_turn_left ||
7129                        !can_turn_right ||
7130                        IN_LEV_FIELD_AND_NOT_FREE(x + move_dx + left_dx,
7131                                                  y + move_dy + left_dy) ||
7132                        IN_LEV_FIELD_AND_NOT_FREE(x + move_dx + right_dx,
7133                                                  y + move_dy + right_dy)));
7134
7135     if (should_turn_left || should_turn_right || should_move_on)
7136     {
7137       if (should_turn_left && should_turn_right && should_move_on)
7138         MovDir[x][y] = (rnd < rnd_value / 3     ? left_dir :
7139                         rnd < 2 * rnd_value / 3 ? right_dir :
7140                         old_move_dir);
7141       else if (should_turn_left && should_turn_right)
7142         MovDir[x][y] = (rnd < rnd_value / 2 ? left_dir : right_dir);
7143       else if (should_turn_left && should_move_on)
7144         MovDir[x][y] = (rnd < rnd_value / 2 ? left_dir : old_move_dir);
7145       else if (should_turn_right && should_move_on)
7146         MovDir[x][y] = (rnd < rnd_value / 2 ? right_dir : old_move_dir);
7147       else if (should_turn_left)
7148         MovDir[x][y] = left_dir;
7149       else if (should_turn_right)
7150         MovDir[x][y] = right_dir;
7151       else if (should_move_on)
7152         MovDir[x][y] = old_move_dir;
7153     }
7154     else if (can_move_on && rnd > rnd_value / 8)
7155       MovDir[x][y] = old_move_dir;
7156     else if (can_turn_left && can_turn_right)
7157       MovDir[x][y] = (rnd < rnd_value / 2 ? left_dir : right_dir);
7158     else if (can_turn_left && rnd > rnd_value / 8)
7159       MovDir[x][y] = left_dir;
7160     else if (can_turn_right && rnd > rnd_value/8)
7161       MovDir[x][y] = right_dir;
7162     else
7163       MovDir[x][y] = back_dir;
7164
7165     xx = x + move_xy[MovDir[x][y]].dx;
7166     yy = y + move_xy[MovDir[x][y]].dy;
7167
7168     if (!IN_LEV_FIELD(xx, yy) ||
7169         (!IS_FREE(xx, yy) && !IS_FOOD_PIG(Tile[xx][yy])))
7170       MovDir[x][y] = old_move_dir;
7171
7172     MovDelay[x][y] = 0;
7173   }
7174   else if (element == EL_DRAGON)
7175   {
7176     boolean can_turn_left  = DRAGON_CAN_ENTER_FIELD(element, left_x, left_y);
7177     boolean can_turn_right = DRAGON_CAN_ENTER_FIELD(element, right_x, right_y);
7178     boolean can_move_on    = DRAGON_CAN_ENTER_FIELD(element, move_x, move_y);
7179     int rnd_value = 24;
7180     int rnd = RND(rnd_value);
7181
7182     if (can_move_on && rnd > rnd_value / 8)
7183       MovDir[x][y] = old_move_dir;
7184     else if (can_turn_left && can_turn_right)
7185       MovDir[x][y] = (rnd < rnd_value / 2 ? left_dir : right_dir);
7186     else if (can_turn_left && rnd > rnd_value / 8)
7187       MovDir[x][y] = left_dir;
7188     else if (can_turn_right && rnd > rnd_value / 8)
7189       MovDir[x][y] = right_dir;
7190     else
7191       MovDir[x][y] = back_dir;
7192
7193     xx = x + move_xy[MovDir[x][y]].dx;
7194     yy = y + move_xy[MovDir[x][y]].dy;
7195
7196     if (!IN_LEV_FIELD_AND_IS_FREE(xx, yy))
7197       MovDir[x][y] = old_move_dir;
7198
7199     MovDelay[x][y] = 0;
7200   }
7201   else if (element == EL_MOLE)
7202   {
7203     boolean can_move_on =
7204       (MOLE_CAN_ENTER_FIELD(element, move_x, move_y,
7205                             IS_AMOEBOID(Tile[move_x][move_y]) ||
7206                             Tile[move_x][move_y] == EL_AMOEBA_SHRINKING));
7207     if (!can_move_on)
7208     {
7209       boolean can_turn_left =
7210         (MOLE_CAN_ENTER_FIELD(element, left_x, left_y,
7211                               IS_AMOEBOID(Tile[left_x][left_y])));
7212
7213       boolean can_turn_right =
7214         (MOLE_CAN_ENTER_FIELD(element, right_x, right_y,
7215                               IS_AMOEBOID(Tile[right_x][right_y])));
7216
7217       if (can_turn_left && can_turn_right)
7218         MovDir[x][y] = (RND(2) ? left_dir : right_dir);
7219       else if (can_turn_left)
7220         MovDir[x][y] = left_dir;
7221       else
7222         MovDir[x][y] = right_dir;
7223     }
7224
7225     if (MovDir[x][y] != old_move_dir)
7226       MovDelay[x][y] = 9;
7227   }
7228   else if (element == EL_BALLOON)
7229   {
7230     MovDir[x][y] = game.wind_direction;
7231     MovDelay[x][y] = 0;
7232   }
7233   else if (element == EL_SPRING)
7234   {
7235     if (MovDir[x][y] & MV_HORIZONTAL)
7236     {
7237       if (SPRING_CAN_BUMP_FROM_FIELD(move_x, move_y) &&
7238           !SPRING_CAN_ENTER_FIELD(element, x, y + 1))
7239       {
7240         Tile[move_x][move_y] = EL_EMC_SPRING_BUMPER_ACTIVE;
7241         ResetGfxAnimation(move_x, move_y);
7242         TEST_DrawLevelField(move_x, move_y);
7243
7244         MovDir[x][y] = back_dir;
7245       }
7246       else if (!SPRING_CAN_ENTER_FIELD(element, move_x, move_y) ||
7247                SPRING_CAN_ENTER_FIELD(element, x, y + 1))
7248         MovDir[x][y] = MV_NONE;
7249     }
7250
7251     MovDelay[x][y] = 0;
7252   }
7253   else if (element == EL_ROBOT ||
7254            element == EL_SATELLITE ||
7255            element == EL_PENGUIN ||
7256            element == EL_EMC_ANDROID)
7257   {
7258     int attr_x = -1, attr_y = -1;
7259
7260     if (game.all_players_gone)
7261     {
7262       attr_x = game.exit_x;
7263       attr_y = game.exit_y;
7264     }
7265     else
7266     {
7267       int i;
7268
7269       for (i = 0; i < MAX_PLAYERS; i++)
7270       {
7271         struct PlayerInfo *player = &stored_player[i];
7272         int jx = player->jx, jy = player->jy;
7273
7274         if (!player->active)
7275           continue;
7276
7277         if (attr_x == -1 ||
7278             ABS(jx - x) + ABS(jy - y) < ABS(attr_x - x) + ABS(attr_y - y))
7279         {
7280           attr_x = jx;
7281           attr_y = jy;
7282         }
7283       }
7284     }
7285
7286     if (element == EL_ROBOT &&
7287         game.robot_wheel_x >= 0 &&
7288         game.robot_wheel_y >= 0 &&
7289         (Tile[game.robot_wheel_x][game.robot_wheel_y] == EL_ROBOT_WHEEL_ACTIVE ||
7290          game.engine_version < VERSION_IDENT(3,1,0,0)))
7291     {
7292       attr_x = game.robot_wheel_x;
7293       attr_y = game.robot_wheel_y;
7294     }
7295
7296     if (element == EL_PENGUIN)
7297     {
7298       int i;
7299       struct XY *xy = xy_topdown;
7300
7301       for (i = 0; i < NUM_DIRECTIONS; i++)
7302       {
7303         int ex = x + xy[i].x;
7304         int ey = y + xy[i].y;
7305
7306         if (IN_LEV_FIELD(ex, ey) && (Tile[ex][ey] == EL_EXIT_OPEN ||
7307                                      Tile[ex][ey] == EL_EM_EXIT_OPEN ||
7308                                      Tile[ex][ey] == EL_STEEL_EXIT_OPEN ||
7309                                      Tile[ex][ey] == EL_EM_STEEL_EXIT_OPEN))
7310         {
7311           attr_x = ex;
7312           attr_y = ey;
7313           break;
7314         }
7315       }
7316     }
7317
7318     MovDir[x][y] = MV_NONE;
7319     if (attr_x < x)
7320       MovDir[x][y] |= (game.all_players_gone ? MV_RIGHT : MV_LEFT);
7321     else if (attr_x > x)
7322       MovDir[x][y] |= (game.all_players_gone ? MV_LEFT : MV_RIGHT);
7323     if (attr_y < y)
7324       MovDir[x][y] |= (game.all_players_gone ? MV_DOWN : MV_UP);
7325     else if (attr_y > y)
7326       MovDir[x][y] |= (game.all_players_gone ? MV_UP : MV_DOWN);
7327
7328     if (element == EL_ROBOT)
7329     {
7330       int newx, newy;
7331
7332       if (MovDir[x][y] & MV_HORIZONTAL && MovDir[x][y] & MV_VERTICAL)
7333         MovDir[x][y] &= (RND(2) ? MV_HORIZONTAL : MV_VERTICAL);
7334       Moving2Blocked(x, y, &newx, &newy);
7335
7336       if (IN_LEV_FIELD(newx, newy) && IS_FREE_OR_PLAYER(newx, newy))
7337         MovDelay[x][y] = 8 + 8 * !RND(3);
7338       else
7339         MovDelay[x][y] = 16;
7340     }
7341     else if (element == EL_PENGUIN)
7342     {
7343       int newx, newy;
7344
7345       MovDelay[x][y] = 1;
7346
7347       if (MovDir[x][y] & MV_HORIZONTAL && MovDir[x][y] & MV_VERTICAL)
7348       {
7349         boolean first_horiz = RND(2);
7350         int new_move_dir = MovDir[x][y];
7351
7352         MovDir[x][y] =
7353           new_move_dir & (first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7354         Moving2Blocked(x, y, &newx, &newy);
7355
7356         if (PENGUIN_CAN_ENTER_FIELD(element, newx, newy))
7357           return;
7358
7359         MovDir[x][y] =
7360           new_move_dir & (!first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7361         Moving2Blocked(x, y, &newx, &newy);
7362
7363         if (PENGUIN_CAN_ENTER_FIELD(element, newx, newy))
7364           return;
7365
7366         MovDir[x][y] = old_move_dir;
7367         return;
7368       }
7369     }
7370     else if (element == EL_SATELLITE)
7371     {
7372       int newx, newy;
7373
7374       MovDelay[x][y] = 1;
7375
7376       if (MovDir[x][y] & MV_HORIZONTAL && MovDir[x][y] & MV_VERTICAL)
7377       {
7378         boolean first_horiz = RND(2);
7379         int new_move_dir = MovDir[x][y];
7380
7381         MovDir[x][y] =
7382           new_move_dir & (first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7383         Moving2Blocked(x, y, &newx, &newy);
7384
7385         if (SATELLITE_CAN_ENTER_FIELD(newx, newy))
7386           return;
7387
7388         MovDir[x][y] =
7389           new_move_dir & (!first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7390         Moving2Blocked(x, y, &newx, &newy);
7391
7392         if (SATELLITE_CAN_ENTER_FIELD(newx, newy))
7393           return;
7394
7395         MovDir[x][y] = old_move_dir;
7396         return;
7397       }
7398     }
7399     else if (element == EL_EMC_ANDROID)
7400     {
7401       static int check_pos[16] =
7402       {
7403         -1,             //  0 => (invalid)
7404         7,              //  1 => MV_LEFT
7405         3,              //  2 => MV_RIGHT
7406         -1,             //  3 => (invalid)
7407         1,              //  4 =>            MV_UP
7408         0,              //  5 => MV_LEFT  | MV_UP
7409         2,              //  6 => MV_RIGHT | MV_UP
7410         -1,             //  7 => (invalid)
7411         5,              //  8 =>            MV_DOWN
7412         6,              //  9 => MV_LEFT  | MV_DOWN
7413         4,              // 10 => MV_RIGHT | MV_DOWN
7414         -1,             // 11 => (invalid)
7415         -1,             // 12 => (invalid)
7416         -1,             // 13 => (invalid)
7417         -1,             // 14 => (invalid)
7418         -1,             // 15 => (invalid)
7419       };
7420       static struct
7421       {
7422         int dx, dy;
7423         int dir;
7424       } check_xy[8] =
7425       {
7426         { -1, -1,       MV_LEFT  | MV_UP   },
7427         {  0, -1,                  MV_UP   },
7428         { +1, -1,       MV_RIGHT | MV_UP   },
7429         { +1,  0,       MV_RIGHT           },
7430         { +1, +1,       MV_RIGHT | MV_DOWN },
7431         {  0, +1,                  MV_DOWN },
7432         { -1, +1,       MV_LEFT  | MV_DOWN },
7433         { -1,  0,       MV_LEFT            },
7434       };
7435       int start_pos, check_order;
7436       boolean can_clone = FALSE;
7437       int i;
7438
7439       // check if there is any free field around current position
7440       for (i = 0; i < 8; i++)
7441       {
7442         int newx = x + check_xy[i].dx;
7443         int newy = y + check_xy[i].dy;
7444
7445         if (IN_LEV_FIELD_AND_IS_FREE(newx, newy))
7446         {
7447           can_clone = TRUE;
7448
7449           break;
7450         }
7451       }
7452
7453       if (can_clone)            // randomly find an element to clone
7454       {
7455         can_clone = FALSE;
7456
7457         start_pos = check_pos[RND(8)];
7458         check_order = (RND(2) ? -1 : +1);
7459
7460         for (i = 0; i < 8; i++)
7461         {
7462           int pos_raw = start_pos + i * check_order;
7463           int pos = (pos_raw + 8) % 8;
7464           int newx = x + check_xy[pos].dx;
7465           int newy = y + check_xy[pos].dy;
7466
7467           if (ANDROID_CAN_CLONE_FIELD(newx, newy))
7468           {
7469             element_info[element].move_leave_type = LEAVE_TYPE_LIMITED;
7470             element_info[element].move_leave_element = EL_TRIGGER_ELEMENT;
7471
7472             Store[x][y] = Tile[newx][newy];
7473
7474             can_clone = TRUE;
7475
7476             break;
7477           }
7478         }
7479       }
7480
7481       if (can_clone)            // randomly find a direction to move
7482       {
7483         can_clone = FALSE;
7484
7485         start_pos = check_pos[RND(8)];
7486         check_order = (RND(2) ? -1 : +1);
7487
7488         for (i = 0; i < 8; i++)
7489         {
7490           int pos_raw = start_pos + i * check_order;
7491           int pos = (pos_raw + 8) % 8;
7492           int newx = x + check_xy[pos].dx;
7493           int newy = y + check_xy[pos].dy;
7494           int new_move_dir = check_xy[pos].dir;
7495
7496           if (IN_LEV_FIELD_AND_IS_FREE(newx, newy))
7497           {
7498             MovDir[x][y] = new_move_dir;
7499             MovDelay[x][y] = level.android_clone_time * 8 + 1;
7500
7501             can_clone = TRUE;
7502
7503             break;
7504           }
7505         }
7506       }
7507
7508       if (can_clone)            // cloning and moving successful
7509         return;
7510
7511       // cannot clone -- try to move towards player
7512
7513       start_pos = check_pos[MovDir[x][y] & 0x0f];
7514       check_order = (RND(2) ? -1 : +1);
7515
7516       for (i = 0; i < 3; i++)
7517       {
7518         // first check start_pos, then previous/next or (next/previous) pos
7519         int pos_raw = start_pos + (i < 2 ? i : -1) * check_order;
7520         int pos = (pos_raw + 8) % 8;
7521         int newx = x + check_xy[pos].dx;
7522         int newy = y + check_xy[pos].dy;
7523         int new_move_dir = check_xy[pos].dir;
7524
7525         if (IS_PLAYER(newx, newy))
7526           break;
7527
7528         if (ANDROID_CAN_ENTER_FIELD(element, newx, newy))
7529         {
7530           MovDir[x][y] = new_move_dir;
7531           MovDelay[x][y] = level.android_move_time * 8 + 1;
7532
7533           break;
7534         }
7535       }
7536     }
7537   }
7538   else if (move_pattern == MV_TURNING_LEFT ||
7539            move_pattern == MV_TURNING_RIGHT ||
7540            move_pattern == MV_TURNING_LEFT_RIGHT ||
7541            move_pattern == MV_TURNING_RIGHT_LEFT ||
7542            move_pattern == MV_TURNING_RANDOM ||
7543            move_pattern == MV_ALL_DIRECTIONS)
7544   {
7545     boolean can_turn_left =
7546       CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, left_x, left_y);
7547     boolean can_turn_right =
7548       CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, right_x, right_y);
7549
7550     if (element_info[element].move_stepsize == 0)       // "not moving"
7551       return;
7552
7553     if (move_pattern == MV_TURNING_LEFT)
7554       MovDir[x][y] = left_dir;
7555     else if (move_pattern == MV_TURNING_RIGHT)
7556       MovDir[x][y] = right_dir;
7557     else if (move_pattern == MV_TURNING_LEFT_RIGHT)
7558       MovDir[x][y] = (can_turn_left || !can_turn_right ? left_dir : right_dir);
7559     else if (move_pattern == MV_TURNING_RIGHT_LEFT)
7560       MovDir[x][y] = (can_turn_right || !can_turn_left ? right_dir : left_dir);
7561     else if (move_pattern == MV_TURNING_RANDOM)
7562       MovDir[x][y] = (can_turn_left && !can_turn_right ? left_dir :
7563                       can_turn_right && !can_turn_left ? right_dir :
7564                       RND(2) ? left_dir : right_dir);
7565     else if (can_turn_left && can_turn_right)
7566       MovDir[x][y] = (RND(3) ? (RND(2) ? left_dir : right_dir) : back_dir);
7567     else if (can_turn_left)
7568       MovDir[x][y] = (RND(2) ? left_dir : back_dir);
7569     else if (can_turn_right)
7570       MovDir[x][y] = (RND(2) ? right_dir : back_dir);
7571     else
7572       MovDir[x][y] = back_dir;
7573
7574     MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7575   }
7576   else if (move_pattern == MV_HORIZONTAL ||
7577            move_pattern == MV_VERTICAL)
7578   {
7579     if (move_pattern & old_move_dir)
7580       MovDir[x][y] = back_dir;
7581     else if (move_pattern == MV_HORIZONTAL)
7582       MovDir[x][y] = (RND(2) ? MV_LEFT : MV_RIGHT);
7583     else if (move_pattern == MV_VERTICAL)
7584       MovDir[x][y] = (RND(2) ? MV_UP : MV_DOWN);
7585
7586     MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7587   }
7588   else if (move_pattern & MV_ANY_DIRECTION)
7589   {
7590     MovDir[x][y] = move_pattern;
7591     MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7592   }
7593   else if (move_pattern & MV_WIND_DIRECTION)
7594   {
7595     MovDir[x][y] = game.wind_direction;
7596     MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7597   }
7598   else if (move_pattern == MV_ALONG_LEFT_SIDE)
7599   {
7600     if (CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, left_x, left_y))
7601       MovDir[x][y] = left_dir;
7602     else if (!CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, move_x, move_y))
7603       MovDir[x][y] = right_dir;
7604
7605     if (MovDir[x][y] != old_move_dir)
7606       MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7607   }
7608   else if (move_pattern == MV_ALONG_RIGHT_SIDE)
7609   {
7610     if (CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, right_x, right_y))
7611       MovDir[x][y] = right_dir;
7612     else if (!CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, move_x, move_y))
7613       MovDir[x][y] = left_dir;
7614
7615     if (MovDir[x][y] != old_move_dir)
7616       MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7617   }
7618   else if (move_pattern == MV_TOWARDS_PLAYER ||
7619            move_pattern == MV_AWAY_FROM_PLAYER)
7620   {
7621     int attr_x = -1, attr_y = -1;
7622     int newx, newy;
7623     boolean move_away = (move_pattern == MV_AWAY_FROM_PLAYER);
7624
7625     if (game.all_players_gone)
7626     {
7627       attr_x = game.exit_x;
7628       attr_y = game.exit_y;
7629     }
7630     else
7631     {
7632       int i;
7633
7634       for (i = 0; i < MAX_PLAYERS; i++)
7635       {
7636         struct PlayerInfo *player = &stored_player[i];
7637         int jx = player->jx, jy = player->jy;
7638
7639         if (!player->active)
7640           continue;
7641
7642         if (attr_x == -1 ||
7643             ABS(jx - x) + ABS(jy - y) < ABS(attr_x - x) + ABS(attr_y - y))
7644         {
7645           attr_x = jx;
7646           attr_y = jy;
7647         }
7648       }
7649     }
7650
7651     MovDir[x][y] = MV_NONE;
7652     if (attr_x < x)
7653       MovDir[x][y] |= (move_away ? MV_RIGHT : MV_LEFT);
7654     else if (attr_x > x)
7655       MovDir[x][y] |= (move_away ? MV_LEFT : MV_RIGHT);
7656     if (attr_y < y)
7657       MovDir[x][y] |= (move_away ? MV_DOWN : MV_UP);
7658     else if (attr_y > y)
7659       MovDir[x][y] |= (move_away ? MV_UP : MV_DOWN);
7660
7661     MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7662
7663     if (MovDir[x][y] & MV_HORIZONTAL && MovDir[x][y] & MV_VERTICAL)
7664     {
7665       boolean first_horiz = RND(2);
7666       int new_move_dir = MovDir[x][y];
7667
7668       if (element_info[element].move_stepsize == 0)     // "not moving"
7669       {
7670         first_horiz = (ABS(attr_x - x) >= ABS(attr_y - y));
7671         MovDir[x][y] &= (first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7672
7673         return;
7674       }
7675
7676       MovDir[x][y] =
7677         new_move_dir & (first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7678       Moving2Blocked(x, y, &newx, &newy);
7679
7680       if (CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, newx, newy))
7681         return;
7682
7683       MovDir[x][y] =
7684         new_move_dir & (!first_horiz ? MV_HORIZONTAL : MV_VERTICAL);
7685       Moving2Blocked(x, y, &newx, &newy);
7686
7687       if (CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, newx, newy))
7688         return;
7689
7690       MovDir[x][y] = old_move_dir;
7691     }
7692   }
7693   else if (move_pattern == MV_WHEN_PUSHED ||
7694            move_pattern == MV_WHEN_DROPPED)
7695   {
7696     if (!CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, move_x, move_y))
7697       MovDir[x][y] = MV_NONE;
7698
7699     MovDelay[x][y] = 0;
7700   }
7701   else if (move_pattern & MV_MAZE_RUNNER_STYLE)
7702   {
7703     struct XY *test_xy = xy_topdown;
7704     static int test_dir[4] =
7705     {
7706       MV_UP,
7707       MV_LEFT,
7708       MV_RIGHT,
7709       MV_DOWN
7710     };
7711     boolean hunter_mode = (move_pattern == MV_MAZE_HUNTER);
7712     int move_preference = -1000000;     // start with very low preference
7713     int new_move_dir = MV_NONE;
7714     int start_test = RND(4);
7715     int i;
7716
7717     for (i = 0; i < NUM_DIRECTIONS; i++)
7718     {
7719       int j = (start_test + i) % 4;
7720       int move_dir = test_dir[j];
7721       int move_dir_preference;
7722
7723       xx = x + test_xy[j].x;
7724       yy = y + test_xy[j].y;
7725
7726       if (hunter_mode && IN_LEV_FIELD(xx, yy) &&
7727           (IS_PLAYER(xx, yy) || Tile[xx][yy] == EL_PLAYER_IS_LEAVING))
7728       {
7729         new_move_dir = move_dir;
7730
7731         break;
7732       }
7733
7734       if (!CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, xx, yy))
7735         continue;
7736
7737       move_dir_preference = -1 * RunnerVisit[xx][yy];
7738       if (hunter_mode && PlayerVisit[xx][yy] > 0)
7739         move_dir_preference = PlayerVisit[xx][yy];
7740
7741       if (move_dir_preference > move_preference)
7742       {
7743         // prefer field that has not been visited for the longest time
7744         move_preference = move_dir_preference;
7745         new_move_dir = move_dir;
7746       }
7747       else if (move_dir_preference == move_preference &&
7748                move_dir == old_move_dir)
7749       {
7750         // prefer last direction when all directions are preferred equally
7751         move_preference = move_dir_preference;
7752         new_move_dir = move_dir;
7753       }
7754     }
7755
7756     MovDir[x][y] = new_move_dir;
7757     if (old_move_dir != new_move_dir)
7758       MovDelay[x][y] = GET_NEW_MOVE_DELAY(element);
7759   }
7760 }
7761
7762 static void TurnRound(int x, int y)
7763 {
7764   int direction = MovDir[x][y];
7765
7766   TurnRoundExt(x, y);
7767
7768   GfxDir[x][y] = MovDir[x][y];
7769
7770   if (direction != MovDir[x][y])
7771     GfxFrame[x][y] = 0;
7772
7773   if (MovDelay[x][y])
7774     GfxAction[x][y] = ACTION_TURNING_FROM_LEFT + MV_DIR_TO_BIT(direction);
7775
7776   ResetGfxFrame(x, y);
7777 }
7778
7779 static boolean JustBeingPushed(int x, int y)
7780 {
7781   int i;
7782
7783   for (i = 0; i < MAX_PLAYERS; i++)
7784   {
7785     struct PlayerInfo *player = &stored_player[i];
7786
7787     if (player->active && player->is_pushing && player->MovPos)
7788     {
7789       int next_jx = player->jx + (player->jx - player->last_jx);
7790       int next_jy = player->jy + (player->jy - player->last_jy);
7791
7792       if (x == next_jx && y == next_jy)
7793         return TRUE;
7794     }
7795   }
7796
7797   return FALSE;
7798 }
7799
7800 static void StartMoving(int x, int y)
7801 {
7802   boolean started_moving = FALSE;       // some elements can fall _and_ move
7803   int element = Tile[x][y];
7804
7805   if (Stop[x][y])
7806     return;
7807
7808   if (MovDelay[x][y] == 0)
7809     GfxAction[x][y] = ACTION_DEFAULT;
7810
7811   if (CAN_FALL(element) && y < lev_fieldy - 1)
7812   {
7813     if ((x > 0              && IS_PLAYER(x - 1, y)) ||
7814         (x < lev_fieldx - 1 && IS_PLAYER(x + 1, y)))
7815       if (JustBeingPushed(x, y))
7816         return;
7817
7818     if (element == EL_QUICKSAND_FULL)
7819     {
7820       if (IS_FREE(x, y + 1))
7821       {
7822         InitMovingField(x, y, MV_DOWN);
7823         started_moving = TRUE;
7824
7825         Tile[x][y] = EL_QUICKSAND_EMPTYING;
7826 #if USE_QUICKSAND_BD_ROCK_BUGFIX
7827         if (Store[x][y] != EL_ROCK && Store[x][y] != EL_BD_ROCK)
7828           Store[x][y] = EL_ROCK;
7829 #else
7830         Store[x][y] = EL_ROCK;
7831 #endif
7832
7833         PlayLevelSoundAction(x, y, ACTION_EMPTYING);
7834       }
7835       else if (Tile[x][y + 1] == EL_QUICKSAND_EMPTY)
7836       {
7837         if (!MovDelay[x][y])
7838         {
7839           MovDelay[x][y] = TILEY + 1;
7840
7841           ResetGfxAnimation(x, y);
7842           ResetGfxAnimation(x, y + 1);
7843         }
7844
7845         if (MovDelay[x][y])
7846         {
7847           DrawLevelElement(x, y, EL_QUICKSAND_EMPTYING);
7848           DrawLevelElement(x, y + 1, EL_QUICKSAND_FILLING);
7849
7850           MovDelay[x][y]--;
7851           if (MovDelay[x][y])
7852             return;
7853         }
7854
7855         Tile[x][y] = EL_QUICKSAND_EMPTY;
7856         Tile[x][y + 1] = EL_QUICKSAND_FULL;
7857         Store[x][y + 1] = Store[x][y];
7858         Store[x][y] = 0;
7859
7860         PlayLevelSoundAction(x, y, ACTION_FILLING);
7861       }
7862       else if (Tile[x][y + 1] == EL_QUICKSAND_FAST_EMPTY)
7863       {
7864         if (!MovDelay[x][y])
7865         {
7866           MovDelay[x][y] = TILEY + 1;
7867
7868           ResetGfxAnimation(x, y);
7869           ResetGfxAnimation(x, y + 1);
7870         }
7871
7872         if (MovDelay[x][y])
7873         {
7874           DrawLevelElement(x, y, EL_QUICKSAND_EMPTYING);
7875           DrawLevelElement(x, y + 1, EL_QUICKSAND_FAST_FILLING);
7876
7877           MovDelay[x][y]--;
7878           if (MovDelay[x][y])
7879             return;
7880         }
7881
7882         Tile[x][y] = EL_QUICKSAND_EMPTY;
7883         Tile[x][y + 1] = EL_QUICKSAND_FAST_FULL;
7884         Store[x][y + 1] = Store[x][y];
7885         Store[x][y] = 0;
7886
7887         PlayLevelSoundAction(x, y, ACTION_FILLING);
7888       }
7889     }
7890     else if (element == EL_QUICKSAND_FAST_FULL)
7891     {
7892       if (IS_FREE(x, y + 1))
7893       {
7894         InitMovingField(x, y, MV_DOWN);
7895         started_moving = TRUE;
7896
7897         Tile[x][y] = EL_QUICKSAND_FAST_EMPTYING;
7898 #if USE_QUICKSAND_BD_ROCK_BUGFIX
7899         if (Store[x][y] != EL_ROCK && Store[x][y] != EL_BD_ROCK)
7900           Store[x][y] = EL_ROCK;
7901 #else
7902         Store[x][y] = EL_ROCK;
7903 #endif
7904
7905         PlayLevelSoundAction(x, y, ACTION_EMPTYING);
7906       }
7907       else if (Tile[x][y + 1] == EL_QUICKSAND_FAST_EMPTY)
7908       {
7909         if (!MovDelay[x][y])
7910         {
7911           MovDelay[x][y] = TILEY + 1;
7912
7913           ResetGfxAnimation(x, y);
7914           ResetGfxAnimation(x, y + 1);
7915         }
7916
7917         if (MovDelay[x][y])
7918         {
7919           DrawLevelElement(x, y, EL_QUICKSAND_FAST_EMPTYING);
7920           DrawLevelElement(x, y + 1, EL_QUICKSAND_FAST_FILLING);
7921
7922           MovDelay[x][y]--;
7923           if (MovDelay[x][y])
7924             return;
7925         }
7926
7927         Tile[x][y] = EL_QUICKSAND_FAST_EMPTY;
7928         Tile[x][y + 1] = EL_QUICKSAND_FAST_FULL;
7929         Store[x][y + 1] = Store[x][y];
7930         Store[x][y] = 0;
7931
7932         PlayLevelSoundAction(x, y, ACTION_FILLING);
7933       }
7934       else if (Tile[x][y + 1] == EL_QUICKSAND_EMPTY)
7935       {
7936         if (!MovDelay[x][y])
7937         {
7938           MovDelay[x][y] = TILEY + 1;
7939
7940           ResetGfxAnimation(x, y);
7941           ResetGfxAnimation(x, y + 1);
7942         }
7943
7944         if (MovDelay[x][y])
7945         {
7946           DrawLevelElement(x, y, EL_QUICKSAND_FAST_EMPTYING);
7947           DrawLevelElement(x, y + 1, EL_QUICKSAND_FILLING);
7948
7949           MovDelay[x][y]--;
7950           if (MovDelay[x][y])
7951             return;
7952         }
7953
7954         Tile[x][y] = EL_QUICKSAND_FAST_EMPTY;
7955         Tile[x][y + 1] = EL_QUICKSAND_FULL;
7956         Store[x][y + 1] = Store[x][y];
7957         Store[x][y] = 0;
7958
7959         PlayLevelSoundAction(x, y, ACTION_FILLING);
7960       }
7961     }
7962     else if ((element == EL_ROCK || element == EL_BD_ROCK) &&
7963              Tile[x][y + 1] == EL_QUICKSAND_EMPTY)
7964     {
7965       InitMovingField(x, y, MV_DOWN);
7966       started_moving = TRUE;
7967
7968       Tile[x][y] = EL_QUICKSAND_FILLING;
7969       Store[x][y] = element;
7970
7971       PlayLevelSoundAction(x, y, ACTION_FILLING);
7972     }
7973     else if ((element == EL_ROCK || element == EL_BD_ROCK) &&
7974              Tile[x][y + 1] == EL_QUICKSAND_FAST_EMPTY)
7975     {
7976       InitMovingField(x, y, MV_DOWN);
7977       started_moving = TRUE;
7978
7979       Tile[x][y] = EL_QUICKSAND_FAST_FILLING;
7980       Store[x][y] = element;
7981
7982       PlayLevelSoundAction(x, y, ACTION_FILLING);
7983     }
7984     else if (element == EL_MAGIC_WALL_FULL)
7985     {
7986       if (IS_FREE(x, y + 1))
7987       {
7988         InitMovingField(x, y, MV_DOWN);
7989         started_moving = TRUE;
7990
7991         Tile[x][y] = EL_MAGIC_WALL_EMPTYING;
7992         Store[x][y] = EL_CHANGED(Store[x][y]);
7993       }
7994       else if (Tile[x][y + 1] == EL_MAGIC_WALL_ACTIVE)
7995       {
7996         if (!MovDelay[x][y])
7997           MovDelay[x][y] = TILEY / 4 + 1;
7998
7999         if (MovDelay[x][y])
8000         {
8001           MovDelay[x][y]--;
8002           if (MovDelay[x][y])
8003             return;
8004         }
8005
8006         Tile[x][y] = EL_MAGIC_WALL_ACTIVE;
8007         Tile[x][y + 1] = EL_MAGIC_WALL_FULL;
8008         Store[x][y + 1] = EL_CHANGED(Store[x][y]);
8009         Store[x][y] = 0;
8010       }
8011     }
8012     else if (element == EL_BD_MAGIC_WALL_FULL)
8013     {
8014       if (IS_FREE(x, y + 1))
8015       {
8016         InitMovingField(x, y, MV_DOWN);
8017         started_moving = TRUE;
8018
8019         Tile[x][y] = EL_BD_MAGIC_WALL_EMPTYING;
8020         Store[x][y] = EL_CHANGED_BD(Store[x][y]);
8021       }
8022       else if (Tile[x][y + 1] == EL_BD_MAGIC_WALL_ACTIVE)
8023       {
8024         if (!MovDelay[x][y])
8025           MovDelay[x][y] = TILEY / 4 + 1;
8026
8027         if (MovDelay[x][y])
8028         {
8029           MovDelay[x][y]--;
8030           if (MovDelay[x][y])
8031             return;
8032         }
8033
8034         Tile[x][y] = EL_BD_MAGIC_WALL_ACTIVE;
8035         Tile[x][y + 1] = EL_BD_MAGIC_WALL_FULL;
8036         Store[x][y + 1] = EL_CHANGED_BD(Store[x][y]);
8037         Store[x][y] = 0;
8038       }
8039     }
8040     else if (element == EL_DC_MAGIC_WALL_FULL)
8041     {
8042       if (IS_FREE(x, y + 1))
8043       {
8044         InitMovingField(x, y, MV_DOWN);
8045         started_moving = TRUE;
8046
8047         Tile[x][y] = EL_DC_MAGIC_WALL_EMPTYING;
8048         Store[x][y] = EL_CHANGED_DC(Store[x][y]);
8049       }
8050       else if (Tile[x][y + 1] == EL_DC_MAGIC_WALL_ACTIVE)
8051       {
8052         if (!MovDelay[x][y])
8053           MovDelay[x][y] = TILEY / 4 + 1;
8054
8055         if (MovDelay[x][y])
8056         {
8057           MovDelay[x][y]--;
8058           if (MovDelay[x][y])
8059             return;
8060         }
8061
8062         Tile[x][y] = EL_DC_MAGIC_WALL_ACTIVE;
8063         Tile[x][y + 1] = EL_DC_MAGIC_WALL_FULL;
8064         Store[x][y + 1] = EL_CHANGED_DC(Store[x][y]);
8065         Store[x][y] = 0;
8066       }
8067     }
8068     else if ((CAN_PASS_MAGIC_WALL(element) &&
8069               (Tile[x][y + 1] == EL_MAGIC_WALL_ACTIVE ||
8070                Tile[x][y + 1] == EL_BD_MAGIC_WALL_ACTIVE)) ||
8071              (CAN_PASS_DC_MAGIC_WALL(element) &&
8072               (Tile[x][y + 1] == EL_DC_MAGIC_WALL_ACTIVE)))
8073
8074     {
8075       InitMovingField(x, y, MV_DOWN);
8076       started_moving = TRUE;
8077
8078       Tile[x][y] =
8079         (Tile[x][y + 1] == EL_MAGIC_WALL_ACTIVE ? EL_MAGIC_WALL_FILLING :
8080          Tile[x][y + 1] == EL_BD_MAGIC_WALL_ACTIVE ? EL_BD_MAGIC_WALL_FILLING :
8081          EL_DC_MAGIC_WALL_FILLING);
8082       Store[x][y] = element;
8083     }
8084     else if (CAN_FALL(element) && Tile[x][y + 1] == EL_ACID)
8085     {
8086       SplashAcid(x, y + 1);
8087
8088       InitMovingField(x, y, MV_DOWN);
8089       started_moving = TRUE;
8090
8091       Store[x][y] = EL_ACID;
8092     }
8093     else if (
8094              (game.engine_version >= VERSION_IDENT(3,1,0,0) &&
8095               CheckImpact[x][y] && !IS_FREE(x, y + 1)) ||
8096              (game.engine_version >= VERSION_IDENT(3,0,7,0) &&
8097               CAN_FALL(element) && WasJustFalling[x][y] &&
8098               (Tile[x][y + 1] == EL_BLOCKED || IS_PLAYER(x, y + 1))) ||
8099
8100              (game.engine_version < VERSION_IDENT(2,2,0,7) &&
8101               CAN_FALL(element) && WasJustMoving[x][y] && !Pushed[x][y + 1] &&
8102               (Tile[x][y + 1] == EL_BLOCKED)))
8103     {
8104       /* this is needed for a special case not covered by calling "Impact()"
8105          from "ContinueMoving()": if an element moves to a tile directly below
8106          another element which was just falling on that tile (which was empty
8107          in the previous frame), the falling element above would just stop
8108          instead of smashing the element below (in previous version, the above
8109          element was just checked for "moving" instead of "falling", resulting
8110          in incorrect smashes caused by horizontal movement of the above
8111          element; also, the case of the player being the element to smash was
8112          simply not covered here... :-/ ) */
8113
8114       CheckCollision[x][y] = 0;
8115       CheckImpact[x][y] = 0;
8116
8117       Impact(x, y);
8118     }
8119     else if (IS_FREE(x, y + 1) && element == EL_SPRING && level.use_spring_bug)
8120     {
8121       if (MovDir[x][y] == MV_NONE)
8122       {
8123         InitMovingField(x, y, MV_DOWN);
8124         started_moving = TRUE;
8125       }
8126     }
8127     else if (IS_FREE(x, y + 1) || Tile[x][y + 1] == EL_DIAMOND_BREAKING)
8128     {
8129       if (WasJustFalling[x][y]) // prevent animation from being restarted
8130         MovDir[x][y] = MV_DOWN;
8131
8132       InitMovingField(x, y, MV_DOWN);
8133       started_moving = TRUE;
8134     }
8135     else if (element == EL_AMOEBA_DROP)
8136     {
8137       Tile[x][y] = EL_AMOEBA_GROWING;
8138       Store[x][y] = EL_AMOEBA_WET;
8139     }
8140     else if (((IS_SLIPPERY(Tile[x][y + 1]) && !IS_PLAYER(x, y + 1)) ||
8141               (IS_EM_SLIPPERY_WALL(Tile[x][y + 1]) && IS_GEM(element))) &&
8142              !IS_FALLING(x, y + 1) && !WasJustMoving[x][y + 1] &&
8143              element != EL_DX_SUPABOMB && element != EL_SP_DISK_ORANGE)
8144     {
8145       boolean can_fall_left  = (x > 0 && IS_FREE(x - 1, y) &&
8146                                 (IS_FREE(x - 1, y + 1) ||
8147                                  Tile[x - 1][y + 1] == EL_ACID));
8148       boolean can_fall_right = (x < lev_fieldx - 1 && IS_FREE(x + 1, y) &&
8149                                 (IS_FREE(x + 1, y + 1) ||
8150                                  Tile[x + 1][y + 1] == EL_ACID));
8151       boolean can_fall_any  = (can_fall_left || can_fall_right);
8152       boolean can_fall_both = (can_fall_left && can_fall_right);
8153       int slippery_type = element_info[Tile[x][y + 1]].slippery_type;
8154
8155       if (can_fall_any && slippery_type != SLIPPERY_ANY_RANDOM)
8156       {
8157         if (slippery_type == SLIPPERY_ANY_LEFT_RIGHT && can_fall_both)
8158           can_fall_right = FALSE;
8159         else if (slippery_type == SLIPPERY_ANY_RIGHT_LEFT && can_fall_both)
8160           can_fall_left = FALSE;
8161         else if (slippery_type == SLIPPERY_ONLY_LEFT)
8162           can_fall_right = FALSE;
8163         else if (slippery_type == SLIPPERY_ONLY_RIGHT)
8164           can_fall_left = FALSE;
8165
8166         can_fall_any  = (can_fall_left || can_fall_right);
8167         can_fall_both = FALSE;
8168       }
8169
8170       if (can_fall_both)
8171       {
8172         if (element == EL_BD_ROCK || element == EL_BD_DIAMOND)
8173           can_fall_right = FALSE;       // slip down on left side
8174         else
8175           can_fall_left = !(can_fall_right = RND(2));
8176
8177         can_fall_both = FALSE;
8178       }
8179
8180       if (can_fall_any)
8181       {
8182         // if not determined otherwise, prefer left side for slipping down
8183         InitMovingField(x, y, can_fall_left ? MV_LEFT : MV_RIGHT);
8184         started_moving = TRUE;
8185       }
8186     }
8187     else if (IS_BELT_ACTIVE(Tile[x][y + 1]))
8188     {
8189       boolean left_is_free  = (x > 0 && IS_FREE(x - 1, y));
8190       boolean right_is_free = (x < lev_fieldx - 1 && IS_FREE(x + 1, y));
8191       int belt_nr = getBeltNrFromBeltActiveElement(Tile[x][y + 1]);
8192       int belt_dir = game.belt_dir[belt_nr];
8193
8194       if ((belt_dir == MV_LEFT  && left_is_free) ||
8195           (belt_dir == MV_RIGHT && right_is_free))
8196       {
8197         int nextx = (belt_dir == MV_LEFT ? x - 1 : x + 1);
8198
8199         InitMovingField(x, y, belt_dir);
8200         started_moving = TRUE;
8201
8202         Pushed[x][y] = TRUE;
8203         Pushed[nextx][y] = TRUE;
8204
8205         GfxAction[x][y] = ACTION_DEFAULT;
8206       }
8207       else
8208       {
8209         MovDir[x][y] = 0;       // if element was moving, stop it
8210       }
8211     }
8212   }
8213
8214   // not "else if" because of elements that can fall and move (EL_SPRING)
8215   if (CAN_MOVE(element) && !started_moving)
8216   {
8217     int move_pattern = element_info[element].move_pattern;
8218     int newx, newy;
8219
8220     Moving2Blocked(x, y, &newx, &newy);
8221
8222     if (IS_PUSHABLE(element) && JustBeingPushed(x, y))
8223       return;
8224
8225     if (game.engine_version >= VERSION_IDENT(3,1,0,0) &&
8226         CheckCollision[x][y] && !IN_LEV_FIELD_AND_IS_FREE(newx, newy))
8227     {
8228       WasJustMoving[x][y] = 0;
8229       CheckCollision[x][y] = 0;
8230
8231       TestIfElementHitsCustomElement(x, y, MovDir[x][y]);
8232
8233       if (Tile[x][y] != element)        // element has changed
8234         return;
8235     }
8236
8237     if (!MovDelay[x][y])        // start new movement phase
8238     {
8239       // all objects that can change their move direction after each step
8240       // (YAMYAM, DARK_YAMYAM and PACMAN go straight until they hit a wall
8241
8242       if (element != EL_YAMYAM &&
8243           element != EL_DARK_YAMYAM &&
8244           element != EL_PACMAN &&
8245           !(move_pattern & MV_ANY_DIRECTION) &&
8246           move_pattern != MV_TURNING_LEFT &&
8247           move_pattern != MV_TURNING_RIGHT &&
8248           move_pattern != MV_TURNING_LEFT_RIGHT &&
8249           move_pattern != MV_TURNING_RIGHT_LEFT &&
8250           move_pattern != MV_TURNING_RANDOM)
8251       {
8252         TurnRound(x, y);
8253
8254         if (MovDelay[x][y] && (element == EL_BUG ||
8255                                element == EL_SPACESHIP ||
8256                                element == EL_SP_SNIKSNAK ||
8257                                element == EL_SP_ELECTRON ||
8258                                element == EL_MOLE))
8259           TEST_DrawLevelField(x, y);
8260       }
8261     }
8262
8263     if (MovDelay[x][y])         // wait some time before next movement
8264     {
8265       MovDelay[x][y]--;
8266
8267       if (element == EL_ROBOT ||
8268           element == EL_YAMYAM ||
8269           element == EL_DARK_YAMYAM)
8270       {
8271         DrawLevelElementAnimationIfNeeded(x, y, element);
8272         PlayLevelSoundAction(x, y, ACTION_WAITING);
8273       }
8274       else if (element == EL_SP_ELECTRON)
8275         DrawLevelElementAnimationIfNeeded(x, y, element);
8276       else if (element == EL_DRAGON)
8277       {
8278         int i;
8279         int dir = MovDir[x][y];
8280         int dx = (dir == MV_LEFT ? -1 : dir == MV_RIGHT ? +1 : 0);
8281         int dy = (dir == MV_UP   ? -1 : dir == MV_DOWN  ? +1 : 0);
8282         int graphic = (dir == MV_LEFT   ? IMG_FLAMES_1_LEFT :
8283                        dir == MV_RIGHT  ? IMG_FLAMES_1_RIGHT :
8284                        dir == MV_UP     ? IMG_FLAMES_1_UP :
8285                        dir == MV_DOWN   ? IMG_FLAMES_1_DOWN : IMG_EMPTY);
8286         int frame = getGraphicAnimationFrameXY(graphic, x, y);
8287
8288         GfxAction[x][y] = ACTION_ATTACKING;
8289
8290         if (IS_PLAYER(x, y))
8291           DrawPlayerField(x, y);
8292         else
8293           TEST_DrawLevelField(x, y);
8294
8295         PlayLevelSoundActionIfLoop(x, y, ACTION_ATTACKING);
8296
8297         for (i = 1; i <= 3; i++)
8298         {
8299           int xx = x + i * dx;
8300           int yy = y + i * dy;
8301           int sx = SCREENX(xx);
8302           int sy = SCREENY(yy);
8303           int flame_graphic = graphic + (i - 1);
8304
8305           if (!IN_LEV_FIELD(xx, yy) || IS_DRAGONFIRE_PROOF(Tile[xx][yy]))
8306             break;
8307
8308           if (MovDelay[x][y])
8309           {
8310             int flamed = MovingOrBlocked2Element(xx, yy);
8311
8312             if (IS_CLASSIC_ENEMY(flamed) || CAN_EXPLODE_BY_DRAGONFIRE(flamed))
8313               Bang(xx, yy);
8314             else
8315               RemoveMovingField(xx, yy);
8316
8317             ChangeDelay[xx][yy] = 0;
8318
8319             Tile[xx][yy] = EL_FLAMES;
8320
8321             if (IN_SCR_FIELD(sx, sy))
8322             {
8323               TEST_DrawLevelFieldCrumbled(xx, yy);
8324               DrawScreenGraphic(sx, sy, flame_graphic, frame);
8325             }
8326           }
8327           else
8328           {
8329             if (Tile[xx][yy] == EL_FLAMES)
8330               Tile[xx][yy] = EL_EMPTY;
8331             TEST_DrawLevelField(xx, yy);
8332           }
8333         }
8334       }
8335
8336       if (MovDelay[x][y])       // element still has to wait some time
8337       {
8338         PlayLevelSoundAction(x, y, ACTION_WAITING);
8339
8340         return;
8341       }
8342     }
8343
8344     // now make next step
8345
8346     Moving2Blocked(x, y, &newx, &newy); // get next screen position
8347
8348     if (DONT_COLLIDE_WITH(element) &&
8349         IN_LEV_FIELD(newx, newy) && IS_PLAYER(newx, newy) &&
8350         !PLAYER_ENEMY_PROTECTED(newx, newy))
8351     {
8352       TestIfBadThingRunsIntoPlayer(x, y, MovDir[x][y]);
8353
8354       return;
8355     }
8356
8357     else if (CAN_MOVE_INTO_ACID(element) &&
8358              IN_LEV_FIELD(newx, newy) && Tile[newx][newy] == EL_ACID &&
8359              !IS_MV_DIAGONAL(MovDir[x][y]) &&
8360              (MovDir[x][y] == MV_DOWN ||
8361               game.engine_version >= VERSION_IDENT(3,1,0,0)))
8362     {
8363       SplashAcid(newx, newy);
8364       Store[x][y] = EL_ACID;
8365     }
8366     else if (element == EL_PENGUIN && IN_LEV_FIELD(newx, newy))
8367     {
8368       if (Tile[newx][newy] == EL_EXIT_OPEN ||
8369           Tile[newx][newy] == EL_EM_EXIT_OPEN ||
8370           Tile[newx][newy] == EL_STEEL_EXIT_OPEN ||
8371           Tile[newx][newy] == EL_EM_STEEL_EXIT_OPEN)
8372       {
8373         RemoveField(x, y);
8374         TEST_DrawLevelField(x, y);
8375
8376         PlayLevelSound(newx, newy, SND_PENGUIN_PASSING);
8377         if (IN_SCR_FIELD(SCREENX(newx), SCREENY(newy)))
8378           DrawGraphicThruMask(SCREENX(newx), SCREENY(newy), el2img(element), 0);
8379
8380         game.friends_still_needed--;
8381         if (!game.friends_still_needed &&
8382             !game.GameOver &&
8383             game.all_players_gone)
8384           LevelSolved();
8385
8386         return;
8387       }
8388       else if (IS_FOOD_PENGUIN(Tile[newx][newy]))
8389       {
8390         if (DigField(local_player, x, y, newx, newy, 0, 0, DF_DIG) == MP_MOVING)
8391           TEST_DrawLevelField(newx, newy);
8392         else
8393           GfxDir[x][y] = MovDir[x][y] = MV_NONE;
8394       }
8395       else if (!IS_FREE(newx, newy))
8396       {
8397         GfxAction[x][y] = ACTION_WAITING;
8398
8399         if (IS_PLAYER(x, y))
8400           DrawPlayerField(x, y);
8401         else
8402           TEST_DrawLevelField(x, y);
8403
8404         return;
8405       }
8406     }
8407     else if (element == EL_PIG && IN_LEV_FIELD(newx, newy))
8408     {
8409       if (IS_FOOD_PIG(Tile[newx][newy]))
8410       {
8411         if (IS_MOVING(newx, newy))
8412           RemoveMovingField(newx, newy);
8413         else
8414         {
8415           Tile[newx][newy] = EL_EMPTY;
8416           TEST_DrawLevelField(newx, newy);
8417         }
8418
8419         PlayLevelSound(x, y, SND_PIG_DIGGING);
8420       }
8421       else if (!IS_FREE(newx, newy))
8422       {
8423         if (IS_PLAYER(x, y))
8424           DrawPlayerField(x, y);
8425         else
8426           TEST_DrawLevelField(x, y);
8427
8428         return;
8429       }
8430     }
8431     else if (element == EL_EMC_ANDROID && IN_LEV_FIELD(newx, newy))
8432     {
8433       if (Store[x][y] != EL_EMPTY)
8434       {
8435         boolean can_clone = FALSE;
8436         int xx, yy;
8437
8438         // check if element to clone is still there
8439         for (yy = y - 1; yy <= y + 1; yy++) for (xx = x - 1; xx <= x + 1; xx++)
8440         {
8441           if (IN_LEV_FIELD(xx, yy) && Tile[xx][yy] == Store[x][y])
8442           {
8443             can_clone = TRUE;
8444
8445             break;
8446           }
8447         }
8448
8449         // cannot clone or target field not free anymore -- do not clone
8450         if (!can_clone || !ANDROID_CAN_ENTER_FIELD(element, newx, newy))
8451           Store[x][y] = EL_EMPTY;
8452       }
8453
8454       if (ANDROID_CAN_ENTER_FIELD(element, newx, newy))
8455       {
8456         if (IS_MV_DIAGONAL(MovDir[x][y]))
8457         {
8458           int diagonal_move_dir = MovDir[x][y];
8459           int stored = Store[x][y];
8460           int change_delay = 8;
8461           int graphic;
8462
8463           // android is moving diagonally
8464
8465           CreateField(x, y, EL_DIAGONAL_SHRINKING);
8466
8467           Store[x][y] = (stored == EL_ACID ? EL_EMPTY : stored);
8468           GfxElement[x][y] = EL_EMC_ANDROID;
8469           GfxAction[x][y] = ACTION_SHRINKING;
8470           GfxDir[x][y] = diagonal_move_dir;
8471           ChangeDelay[x][y] = change_delay;
8472
8473           if (Store[x][y] == EL_EMPTY)
8474             Store[x][y] = GfxElementEmpty[x][y];
8475
8476           graphic = el_act_dir2img(GfxElement[x][y], GfxAction[x][y],
8477                                    GfxDir[x][y]);
8478
8479           DrawLevelGraphicAnimation(x, y, graphic);
8480           PlayLevelSoundAction(x, y, ACTION_SHRINKING);
8481
8482           if (Tile[newx][newy] == EL_ACID)
8483           {
8484             SplashAcid(newx, newy);
8485
8486             return;
8487           }
8488
8489           CreateField(newx, newy, EL_DIAGONAL_GROWING);
8490
8491           Store[newx][newy] = EL_EMC_ANDROID;
8492           GfxElement[newx][newy] = EL_EMC_ANDROID;
8493           GfxAction[newx][newy] = ACTION_GROWING;
8494           GfxDir[newx][newy] = diagonal_move_dir;
8495           ChangeDelay[newx][newy] = change_delay;
8496
8497           graphic = el_act_dir2img(GfxElement[newx][newy],
8498                                    GfxAction[newx][newy], GfxDir[newx][newy]);
8499
8500           DrawLevelGraphicAnimation(newx, newy, graphic);
8501           PlayLevelSoundAction(newx, newy, ACTION_GROWING);
8502
8503           return;
8504         }
8505         else
8506         {
8507           Tile[newx][newy] = EL_EMPTY;
8508           TEST_DrawLevelField(newx, newy);
8509
8510           PlayLevelSoundAction(x, y, ACTION_DIGGING);
8511         }
8512       }
8513       else if (!IS_FREE(newx, newy))
8514       {
8515         return;
8516       }
8517     }
8518     else if (IS_CUSTOM_ELEMENT(element) &&
8519              CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, newx, newy))
8520     {
8521       if (!DigFieldByCE(newx, newy, element))
8522         return;
8523
8524       if (move_pattern & MV_MAZE_RUNNER_STYLE)
8525       {
8526         RunnerVisit[x][y] = FrameCounter;
8527         PlayerVisit[x][y] /= 8;         // expire player visit path
8528       }
8529     }
8530     else if (element == EL_DRAGON && IN_LEV_FIELD(newx, newy))
8531     {
8532       if (!IS_FREE(newx, newy))
8533       {
8534         if (IS_PLAYER(x, y))
8535           DrawPlayerField(x, y);
8536         else
8537           TEST_DrawLevelField(x, y);
8538
8539         return;
8540       }
8541       else
8542       {
8543         boolean wanna_flame = !RND(10);
8544         int dx = newx - x, dy = newy - y;
8545         int newx1 = newx + 1 * dx, newy1 = newy + 1 * dy;
8546         int newx2 = newx + 2 * dx, newy2 = newy + 2 * dy;
8547         int element1 = (IN_LEV_FIELD(newx1, newy1) ?
8548                         MovingOrBlocked2Element(newx1, newy1) : EL_STEELWALL);
8549         int element2 = (IN_LEV_FIELD(newx2, newy2) ?
8550                         MovingOrBlocked2Element(newx2, newy2) : EL_STEELWALL);
8551
8552         if ((wanna_flame ||
8553              IS_CLASSIC_ENEMY(element1) ||
8554              IS_CLASSIC_ENEMY(element2)) &&
8555             element1 != EL_DRAGON && element2 != EL_DRAGON &&
8556             element1 != EL_FLAMES && element2 != EL_FLAMES)
8557         {
8558           ResetGfxAnimation(x, y);
8559           GfxAction[x][y] = ACTION_ATTACKING;
8560
8561           if (IS_PLAYER(x, y))
8562             DrawPlayerField(x, y);
8563           else
8564             TEST_DrawLevelField(x, y);
8565
8566           PlayLevelSound(x, y, SND_DRAGON_ATTACKING);
8567
8568           MovDelay[x][y] = 50;
8569
8570           Tile[newx][newy] = EL_FLAMES;
8571           if (IN_LEV_FIELD(newx1, newy1) && Tile[newx1][newy1] == EL_EMPTY)
8572             Tile[newx1][newy1] = EL_FLAMES;
8573           if (IN_LEV_FIELD(newx2, newy2) && Tile[newx2][newy2] == EL_EMPTY)
8574             Tile[newx2][newy2] = EL_FLAMES;
8575
8576           return;
8577         }
8578       }
8579     }
8580     else if (element == EL_YAMYAM && IN_LEV_FIELD(newx, newy) &&
8581              Tile[newx][newy] == EL_DIAMOND)
8582     {
8583       if (IS_MOVING(newx, newy))
8584         RemoveMovingField(newx, newy);
8585       else
8586       {
8587         Tile[newx][newy] = EL_EMPTY;
8588         TEST_DrawLevelField(newx, newy);
8589       }
8590
8591       PlayLevelSound(x, y, SND_YAMYAM_DIGGING);
8592     }
8593     else if (element == EL_DARK_YAMYAM && IN_LEV_FIELD(newx, newy) &&
8594              IS_FOOD_DARK_YAMYAM(Tile[newx][newy]))
8595     {
8596       if (AmoebaNr[newx][newy])
8597       {
8598         AmoebaCnt2[AmoebaNr[newx][newy]]--;
8599         if (Tile[newx][newy] == EL_AMOEBA_FULL ||
8600             Tile[newx][newy] == EL_BD_AMOEBA)
8601           AmoebaCnt[AmoebaNr[newx][newy]]--;
8602       }
8603
8604       if (IS_MOVING(newx, newy))
8605       {
8606         RemoveMovingField(newx, newy);
8607       }
8608       else
8609       {
8610         Tile[newx][newy] = EL_EMPTY;
8611         TEST_DrawLevelField(newx, newy);
8612       }
8613
8614       PlayLevelSound(x, y, SND_DARK_YAMYAM_DIGGING);
8615     }
8616     else if ((element == EL_PACMAN || element == EL_MOLE)
8617              && IN_LEV_FIELD(newx, newy) && IS_AMOEBOID(Tile[newx][newy]))
8618     {
8619       if (AmoebaNr[newx][newy])
8620       {
8621         AmoebaCnt2[AmoebaNr[newx][newy]]--;
8622         if (Tile[newx][newy] == EL_AMOEBA_FULL ||
8623             Tile[newx][newy] == EL_BD_AMOEBA)
8624           AmoebaCnt[AmoebaNr[newx][newy]]--;
8625       }
8626
8627       if (element == EL_MOLE)
8628       {
8629         Tile[newx][newy] = EL_AMOEBA_SHRINKING;
8630         PlayLevelSound(x, y, SND_MOLE_DIGGING);
8631
8632         ResetGfxAnimation(x, y);
8633         GfxAction[x][y] = ACTION_DIGGING;
8634         TEST_DrawLevelField(x, y);
8635
8636         MovDelay[newx][newy] = 0;       // start amoeba shrinking delay
8637
8638         return;                         // wait for shrinking amoeba
8639       }
8640       else      // element == EL_PACMAN
8641       {
8642         Tile[newx][newy] = EL_EMPTY;
8643         TEST_DrawLevelField(newx, newy);
8644         PlayLevelSound(x, y, SND_PACMAN_DIGGING);
8645       }
8646     }
8647     else if (element == EL_MOLE && IN_LEV_FIELD(newx, newy) &&
8648              (Tile[newx][newy] == EL_AMOEBA_SHRINKING ||
8649               (Tile[newx][newy] == EL_EMPTY && Stop[newx][newy])))
8650     {
8651       // wait for shrinking amoeba to completely disappear
8652       return;
8653     }
8654     else if (!IN_LEV_FIELD(newx, newy) || !IS_FREE(newx, newy))
8655     {
8656       // object was running against a wall
8657
8658       TurnRound(x, y);
8659
8660       if (GFX_ELEMENT(element) != EL_SAND)     // !!! FIX THIS (crumble) !!!
8661         DrawLevelElementAnimation(x, y, element);
8662
8663       if (DONT_TOUCH(element))
8664         TestIfBadThingTouchesPlayer(x, y);
8665
8666       return;
8667     }
8668
8669     InitMovingField(x, y, MovDir[x][y]);
8670
8671     PlayLevelSoundAction(x, y, ACTION_MOVING);
8672   }
8673
8674   if (MovDir[x][y])
8675     ContinueMoving(x, y);
8676 }
8677
8678 void ContinueMoving(int x, int y)
8679 {
8680   int element = Tile[x][y];
8681   struct ElementInfo *ei = &element_info[element];
8682   int direction = MovDir[x][y];
8683   int dx = (direction == MV_LEFT ? -1 : direction == MV_RIGHT ? +1 : 0);
8684   int dy = (direction == MV_UP   ? -1 : direction == MV_DOWN  ? +1 : 0);
8685   int newx = x + dx, newy = y + dy;
8686   int stored = Store[x][y];
8687   int stored_new = Store[newx][newy];
8688   boolean pushed_by_player   = (Pushed[x][y] && IS_PLAYER(x, y));
8689   boolean pushed_by_conveyor = (Pushed[x][y] && !IS_PLAYER(x, y));
8690   boolean last_line = (newy == lev_fieldy - 1);
8691   boolean use_step_delay = (GET_MAX_STEP_DELAY(element) != 0);
8692
8693   if (pushed_by_player)         // special case: moving object pushed by player
8694   {
8695     MovPos[x][y] = SIGN(MovPos[x][y]) * (TILEX - ABS(PLAYERINFO(x, y)->MovPos));
8696   }
8697   else if (use_step_delay)      // special case: moving object has step delay
8698   {
8699     if (!MovDelay[x][y])
8700       MovPos[x][y] += getElementMoveStepsize(x, y);
8701
8702     if (MovDelay[x][y])
8703       MovDelay[x][y]--;
8704     else
8705       MovDelay[x][y] = GET_NEW_STEP_DELAY(element);
8706
8707     if (MovDelay[x][y])
8708     {
8709       TEST_DrawLevelField(x, y);
8710
8711       return;   // element is still waiting
8712     }
8713   }
8714   else                          // normal case: generically moving object
8715   {
8716     MovPos[x][y] += getElementMoveStepsize(x, y);
8717   }
8718
8719   if (ABS(MovPos[x][y]) < TILEX)
8720   {
8721     TEST_DrawLevelField(x, y);
8722
8723     return;     // element is still moving
8724   }
8725
8726   // element reached destination field
8727
8728   Tile[x][y] = EL_EMPTY;
8729   Tile[newx][newy] = element;
8730   MovPos[x][y] = 0;     // force "not moving" for "crumbled sand"
8731
8732   if (Store[x][y] == EL_ACID)   // element is moving into acid pool
8733   {
8734     element = Tile[newx][newy] = EL_ACID;
8735   }
8736   else if (element == EL_MOLE)
8737   {
8738     Tile[x][y] = EL_SAND;
8739
8740     TEST_DrawLevelFieldCrumbledNeighbours(x, y);
8741   }
8742   else if (element == EL_QUICKSAND_FILLING)
8743   {
8744     element = Tile[newx][newy] = get_next_element(element);
8745     Store[newx][newy] = Store[x][y];
8746   }
8747   else if (element == EL_QUICKSAND_EMPTYING)
8748   {
8749     Tile[x][y] = get_next_element(element);
8750     element = Tile[newx][newy] = Store[x][y];
8751   }
8752   else if (element == EL_QUICKSAND_FAST_FILLING)
8753   {
8754     element = Tile[newx][newy] = get_next_element(element);
8755     Store[newx][newy] = Store[x][y];
8756   }
8757   else if (element == EL_QUICKSAND_FAST_EMPTYING)
8758   {
8759     Tile[x][y] = get_next_element(element);
8760     element = Tile[newx][newy] = Store[x][y];
8761   }
8762   else if (element == EL_MAGIC_WALL_FILLING)
8763   {
8764     element = Tile[newx][newy] = get_next_element(element);
8765     if (!game.magic_wall_active)
8766       element = Tile[newx][newy] = EL_MAGIC_WALL_DEAD;
8767     Store[newx][newy] = Store[x][y];
8768   }
8769   else if (element == EL_MAGIC_WALL_EMPTYING)
8770   {
8771     Tile[x][y] = get_next_element(element);
8772     if (!game.magic_wall_active)
8773       Tile[x][y] = EL_MAGIC_WALL_DEAD;
8774     element = Tile[newx][newy] = Store[x][y];
8775
8776     InitField(newx, newy, FALSE);
8777   }
8778   else if (element == EL_BD_MAGIC_WALL_FILLING)
8779   {
8780     element = Tile[newx][newy] = get_next_element(element);
8781     if (!game.magic_wall_active)
8782       element = Tile[newx][newy] = EL_BD_MAGIC_WALL_DEAD;
8783     Store[newx][newy] = Store[x][y];
8784   }
8785   else if (element == EL_BD_MAGIC_WALL_EMPTYING)
8786   {
8787     Tile[x][y] = get_next_element(element);
8788     if (!game.magic_wall_active)
8789       Tile[x][y] = EL_BD_MAGIC_WALL_DEAD;
8790     element = Tile[newx][newy] = Store[x][y];
8791
8792     InitField(newx, newy, FALSE);
8793   }
8794   else if (element == EL_DC_MAGIC_WALL_FILLING)
8795   {
8796     element = Tile[newx][newy] = get_next_element(element);
8797     if (!game.magic_wall_active)
8798       element = Tile[newx][newy] = EL_DC_MAGIC_WALL_DEAD;
8799     Store[newx][newy] = Store[x][y];
8800   }
8801   else if (element == EL_DC_MAGIC_WALL_EMPTYING)
8802   {
8803     Tile[x][y] = get_next_element(element);
8804     if (!game.magic_wall_active)
8805       Tile[x][y] = EL_DC_MAGIC_WALL_DEAD;
8806     element = Tile[newx][newy] = Store[x][y];
8807
8808     InitField(newx, newy, FALSE);
8809   }
8810   else if (element == EL_AMOEBA_DROPPING)
8811   {
8812     Tile[x][y] = get_next_element(element);
8813     element = Tile[newx][newy] = Store[x][y];
8814   }
8815   else if (element == EL_SOKOBAN_OBJECT)
8816   {
8817     if (Back[x][y])
8818       Tile[x][y] = Back[x][y];
8819
8820     if (Back[newx][newy])
8821       Tile[newx][newy] = EL_SOKOBAN_FIELD_FULL;
8822
8823     Back[x][y] = Back[newx][newy] = 0;
8824   }
8825
8826   Store[x][y] = EL_EMPTY;
8827   MovPos[x][y] = 0;
8828   MovDir[x][y] = 0;
8829   MovDelay[x][y] = 0;
8830
8831   MovDelay[newx][newy] = 0;
8832
8833   if (CAN_CHANGE_OR_HAS_ACTION(element))
8834   {
8835     // copy element change control values to new field
8836     ChangeDelay[newx][newy] = ChangeDelay[x][y];
8837     ChangePage[newx][newy]  = ChangePage[x][y];
8838     ChangeCount[newx][newy] = ChangeCount[x][y];
8839     ChangeEvent[newx][newy] = ChangeEvent[x][y];
8840   }
8841
8842   CustomValue[newx][newy] = CustomValue[x][y];
8843
8844   ChangeDelay[x][y] = 0;
8845   ChangePage[x][y] = -1;
8846   ChangeCount[x][y] = 0;
8847   ChangeEvent[x][y] = -1;
8848
8849   CustomValue[x][y] = 0;
8850
8851   // copy animation control values to new field
8852   GfxFrame[newx][newy]  = GfxFrame[x][y];
8853   GfxRandom[newx][newy] = GfxRandom[x][y];      // keep same random value
8854   GfxAction[newx][newy] = GfxAction[x][y];      // keep action one frame
8855   GfxDir[newx][newy]    = GfxDir[x][y];         // keep element direction
8856
8857   Pushed[x][y] = Pushed[newx][newy] = FALSE;
8858
8859   // some elements can leave other elements behind after moving
8860   if (ei->move_leave_element != EL_EMPTY &&
8861       (ei->move_leave_type == LEAVE_TYPE_UNLIMITED || stored != EL_EMPTY) &&
8862       (!IS_PLAYER(x, y) || IS_WALKABLE(ei->move_leave_element)))
8863   {
8864     int move_leave_element = ei->move_leave_element;
8865
8866     // this makes it possible to leave the removed element again
8867     if (ei->move_leave_element == EL_TRIGGER_ELEMENT)
8868       move_leave_element = (stored == EL_ACID ? EL_EMPTY : stored);
8869
8870     Tile[x][y] = move_leave_element;
8871
8872     if (element_info[Tile[x][y]].move_direction_initial == MV_START_PREVIOUS)
8873       MovDir[x][y] = direction;
8874
8875     InitField(x, y, FALSE);
8876
8877     if (GFX_CRUMBLED(Tile[x][y]))
8878       TEST_DrawLevelFieldCrumbledNeighbours(x, y);
8879
8880     if (IS_PLAYER_ELEMENT(move_leave_element))
8881       RelocatePlayer(x, y, move_leave_element);
8882   }
8883
8884   // do this after checking for left-behind element
8885   ResetGfxAnimation(x, y);      // reset animation values for old field
8886
8887   if (!CAN_MOVE(element) ||
8888       (CAN_FALL(element) && direction == MV_DOWN &&
8889        (element == EL_SPRING ||
8890         element_info[element].move_pattern == MV_WHEN_PUSHED ||
8891         element_info[element].move_pattern == MV_WHEN_DROPPED)))
8892     GfxDir[x][y] = MovDir[newx][newy] = 0;
8893
8894   TEST_DrawLevelField(x, y);
8895   TEST_DrawLevelField(newx, newy);
8896
8897   Stop[newx][newy] = TRUE;      // ignore this element until the next frame
8898
8899   // prevent pushed element from moving on in pushed direction
8900   if (pushed_by_player && CAN_MOVE(element) &&
8901       element_info[element].move_pattern & MV_ANY_DIRECTION &&
8902       !(element_info[element].move_pattern & direction))
8903     TurnRound(newx, newy);
8904
8905   // prevent elements on conveyor belt from moving on in last direction
8906   if (pushed_by_conveyor && CAN_FALL(element) &&
8907       direction & MV_HORIZONTAL)
8908     MovDir[newx][newy] = 0;
8909
8910   if (!pushed_by_player)
8911   {
8912     int nextx = newx + dx, nexty = newy + dy;
8913     boolean check_collision_again = IN_LEV_FIELD_AND_IS_FREE(nextx, nexty);
8914
8915     WasJustMoving[newx][newy] = CHECK_DELAY_MOVING;
8916
8917     if (CAN_FALL(element) && direction == MV_DOWN)
8918       WasJustFalling[newx][newy] = CHECK_DELAY_FALLING;
8919
8920     if ((!CAN_FALL(element) || direction == MV_DOWN) && check_collision_again)
8921       CheckCollision[newx][newy] = CHECK_DELAY_COLLISION;
8922
8923     if (CAN_FALL(element) && direction == MV_DOWN && check_collision_again)
8924       CheckImpact[newx][newy] = CHECK_DELAY_IMPACT;
8925   }
8926
8927   if (DONT_TOUCH(element))      // object may be nasty to player or others
8928   {
8929     TestIfBadThingTouchesPlayer(newx, newy);
8930     TestIfBadThingTouchesFriend(newx, newy);
8931
8932     if (!IS_CUSTOM_ELEMENT(element))
8933       TestIfBadThingTouchesOtherBadThing(newx, newy);
8934   }
8935   else if (element == EL_PENGUIN)
8936     TestIfFriendTouchesBadThing(newx, newy);
8937
8938   if (DONT_GET_HIT_BY(element))
8939   {
8940     TestIfGoodThingGetsHitByBadThing(newx, newy, direction);
8941   }
8942
8943   // give the player one last chance (one more frame) to move away
8944   if (CAN_FALL(element) && direction == MV_DOWN &&
8945       (last_line || (!IS_FREE(x, newy + 1) &&
8946                      (!IS_PLAYER(x, newy + 1) ||
8947                       game.engine_version < VERSION_IDENT(3,1,1,0)))))
8948     Impact(x, newy);
8949
8950   if (pushed_by_player && !game.use_change_when_pushing_bug)
8951   {
8952     int push_side = MV_DIR_OPPOSITE(direction);
8953     struct PlayerInfo *player = PLAYERINFO(x, y);
8954
8955     CheckElementChangeByPlayer(newx, newy, element, CE_PUSHED_BY_PLAYER,
8956                                player->index_bit, push_side);
8957     CheckTriggeredElementChangeByPlayer(newx, newy, element, CE_PLAYER_PUSHES_X,
8958                                         player->index_bit, push_side);
8959   }
8960
8961   if (element == EL_EMC_ANDROID && pushed_by_player)    // make another move
8962     MovDelay[newx][newy] = 1;
8963
8964   CheckTriggeredElementChangeBySide(x, y, element, CE_MOVE_OF_X, direction);
8965
8966   TestIfElementTouchesCustomElement(x, y);      // empty or new element
8967   TestIfElementHitsCustomElement(newx, newy, direction);
8968   TestIfPlayerTouchesCustomElement(newx, newy);
8969   TestIfElementTouchesCustomElement(newx, newy);
8970
8971   if (IS_CUSTOM_ELEMENT(element) && ei->move_enter_element != EL_EMPTY &&
8972       IS_EQUAL_OR_IN_GROUP(stored_new, ei->move_enter_element))
8973     CheckElementChangeBySide(newx, newy, element, stored_new, CE_DIGGING_X,
8974                              MV_DIR_OPPOSITE(direction));
8975 }
8976
8977 int AmoebaNeighbourNr(int ax, int ay)
8978 {
8979   int i;
8980   int element = Tile[ax][ay];
8981   int group_nr = 0;
8982   struct XY *xy = xy_topdown;
8983
8984   for (i = 0; i < NUM_DIRECTIONS; i++)
8985   {
8986     int x = ax + xy[i].x;
8987     int y = ay + xy[i].y;
8988
8989     if (!IN_LEV_FIELD(x, y))
8990       continue;
8991
8992     if (Tile[x][y] == element && AmoebaNr[x][y] > 0)
8993       group_nr = AmoebaNr[x][y];
8994   }
8995
8996   return group_nr;
8997 }
8998
8999 static void AmoebaMerge(int ax, int ay)
9000 {
9001   int i, x, y, xx, yy;
9002   int new_group_nr = AmoebaNr[ax][ay];
9003   struct XY *xy = xy_topdown;
9004
9005   if (new_group_nr == 0)
9006     return;
9007
9008   for (i = 0; i < NUM_DIRECTIONS; i++)
9009   {
9010     x = ax + xy[i].x;
9011     y = ay + xy[i].y;
9012
9013     if (!IN_LEV_FIELD(x, y))
9014       continue;
9015
9016     if ((Tile[x][y] == EL_AMOEBA_FULL ||
9017          Tile[x][y] == EL_BD_AMOEBA ||
9018          Tile[x][y] == EL_AMOEBA_DEAD) &&
9019         AmoebaNr[x][y] != new_group_nr)
9020     {
9021       int old_group_nr = AmoebaNr[x][y];
9022
9023       if (old_group_nr == 0)
9024         return;
9025
9026       AmoebaCnt[new_group_nr] += AmoebaCnt[old_group_nr];
9027       AmoebaCnt[old_group_nr] = 0;
9028       AmoebaCnt2[new_group_nr] += AmoebaCnt2[old_group_nr];
9029       AmoebaCnt2[old_group_nr] = 0;
9030
9031       SCAN_PLAYFIELD(xx, yy)
9032       {
9033         if (AmoebaNr[xx][yy] == old_group_nr)
9034           AmoebaNr[xx][yy] = new_group_nr;
9035       }
9036     }
9037   }
9038 }
9039
9040 void AmoebaToDiamond(int ax, int ay)
9041 {
9042   int i, x, y;
9043
9044   if (Tile[ax][ay] == EL_AMOEBA_DEAD)
9045   {
9046     int group_nr = AmoebaNr[ax][ay];
9047
9048 #ifdef DEBUG
9049     if (group_nr == 0)
9050     {
9051       Debug("game:playing:AmoebaToDiamond", "ax = %d, ay = %d", ax, ay);
9052       Debug("game:playing:AmoebaToDiamond", "This should never happen!");
9053
9054       return;
9055     }
9056 #endif
9057
9058     SCAN_PLAYFIELD(x, y)
9059     {
9060       if (Tile[x][y] == EL_AMOEBA_DEAD && AmoebaNr[x][y] == group_nr)
9061       {
9062         AmoebaNr[x][y] = 0;
9063         Tile[x][y] = EL_AMOEBA_TO_DIAMOND;
9064       }
9065     }
9066
9067     PlayLevelSound(ax, ay, (IS_GEM(level.amoeba_content) ?
9068                             SND_AMOEBA_TURNING_TO_GEM :
9069                             SND_AMOEBA_TURNING_TO_ROCK));
9070     Bang(ax, ay);
9071   }
9072   else
9073   {
9074     struct XY *xy = xy_topdown;
9075
9076     for (i = 0; i < NUM_DIRECTIONS; i++)
9077     {
9078       x = ax + xy[i].x;
9079       y = ay + xy[i].y;
9080
9081       if (!IN_LEV_FIELD(x, y))
9082         continue;
9083
9084       if (Tile[x][y] == EL_AMOEBA_TO_DIAMOND)
9085       {
9086         PlayLevelSound(x, y, (IS_GEM(level.amoeba_content) ?
9087                               SND_AMOEBA_TURNING_TO_GEM :
9088                               SND_AMOEBA_TURNING_TO_ROCK));
9089         Bang(x, y);
9090       }
9091     }
9092   }
9093 }
9094
9095 static void AmoebaToDiamondBD(int ax, int ay, int new_element)
9096 {
9097   int x, y;
9098   int group_nr = AmoebaNr[ax][ay];
9099   boolean done = FALSE;
9100
9101 #ifdef DEBUG
9102   if (group_nr == 0)
9103   {
9104     Debug("game:playing:AmoebaToDiamondBD", "ax = %d, ay = %d", ax, ay);
9105     Debug("game:playing:AmoebaToDiamondBD", "This should never happen!");
9106
9107     return;
9108   }
9109 #endif
9110
9111   SCAN_PLAYFIELD(x, y)
9112   {
9113     if (AmoebaNr[x][y] == group_nr &&
9114         (Tile[x][y] == EL_AMOEBA_DEAD ||
9115          Tile[x][y] == EL_BD_AMOEBA ||
9116          Tile[x][y] == EL_AMOEBA_GROWING))
9117     {
9118       AmoebaNr[x][y] = 0;
9119       Tile[x][y] = new_element;
9120       InitField(x, y, FALSE);
9121       TEST_DrawLevelField(x, y);
9122       done = TRUE;
9123     }
9124   }
9125
9126   if (done)
9127     PlayLevelSound(ax, ay, (new_element == EL_BD_ROCK ?
9128                             SND_BD_AMOEBA_TURNING_TO_ROCK :
9129                             SND_BD_AMOEBA_TURNING_TO_GEM));
9130 }
9131
9132 static void AmoebaGrowing(int x, int y)
9133 {
9134   static DelayCounter sound_delay = { 0 };
9135
9136   if (!MovDelay[x][y])          // start new growing cycle
9137   {
9138     MovDelay[x][y] = 7;
9139
9140     if (DelayReached(&sound_delay))
9141     {
9142       PlayLevelSoundElementAction(x, y, Store[x][y], ACTION_GROWING);
9143       sound_delay.value = 30;
9144     }
9145   }
9146
9147   if (MovDelay[x][y])           // wait some time before growing bigger
9148   {
9149     MovDelay[x][y]--;
9150     if (MovDelay[x][y]/2 && IN_SCR_FIELD(SCREENX(x), SCREENY(y)))
9151     {
9152       int frame = getGraphicAnimationFrame(IMG_AMOEBA_GROWING,
9153                                            6 - MovDelay[x][y]);
9154
9155       DrawLevelGraphic(x, y, IMG_AMOEBA_GROWING, frame);
9156     }
9157
9158     if (!MovDelay[x][y])
9159     {
9160       Tile[x][y] = Store[x][y];
9161       Store[x][y] = 0;
9162       TEST_DrawLevelField(x, y);
9163     }
9164   }
9165 }
9166
9167 static void AmoebaShrinking(int x, int y)
9168 {
9169   static DelayCounter sound_delay = { 0 };
9170
9171   if (!MovDelay[x][y])          // start new shrinking cycle
9172   {
9173     MovDelay[x][y] = 7;
9174
9175     if (DelayReached(&sound_delay))
9176       sound_delay.value = 30;
9177   }
9178
9179   if (MovDelay[x][y])           // wait some time before shrinking
9180   {
9181     MovDelay[x][y]--;
9182     if (MovDelay[x][y]/2 && IN_SCR_FIELD(SCREENX(x), SCREENY(y)))
9183     {
9184       int frame = getGraphicAnimationFrame(IMG_AMOEBA_SHRINKING,
9185                                            6 - MovDelay[x][y]);
9186
9187       DrawLevelGraphic(x, y, IMG_AMOEBA_SHRINKING, frame);
9188     }
9189
9190     if (!MovDelay[x][y])
9191     {
9192       Tile[x][y] = EL_EMPTY;
9193       TEST_DrawLevelField(x, y);
9194
9195       // don't let mole enter this field in this cycle;
9196       // (give priority to objects falling to this field from above)
9197       Stop[x][y] = TRUE;
9198     }
9199   }
9200 }
9201
9202 static void AmoebaReproduce(int ax, int ay)
9203 {
9204   int i;
9205   int element = Tile[ax][ay];
9206   int graphic = el2img(element);
9207   int newax = ax, neway = ay;
9208   boolean can_drop = (element == EL_AMOEBA_WET || element == EL_EMC_DRIPPER);
9209   struct XY *xy = xy_topdown;
9210
9211   if (!level.amoeba_speed && element != EL_EMC_DRIPPER)
9212   {
9213     Tile[ax][ay] = EL_AMOEBA_DEAD;
9214     TEST_DrawLevelField(ax, ay);
9215     return;
9216   }
9217
9218   if (IS_ANIMATED(graphic))
9219     DrawLevelGraphicAnimationIfNeeded(ax, ay, graphic);
9220
9221   if (!MovDelay[ax][ay])        // start making new amoeba field
9222     MovDelay[ax][ay] = RND(FRAMES_PER_SECOND * 25 / (1 + level.amoeba_speed));
9223
9224   if (MovDelay[ax][ay])         // wait some time before making new amoeba
9225   {
9226     MovDelay[ax][ay]--;
9227     if (MovDelay[ax][ay])
9228       return;
9229   }
9230
9231   if (can_drop)                 // EL_AMOEBA_WET or EL_EMC_DRIPPER
9232   {
9233     int start = RND(4);
9234     int x = ax + xy[start].x;
9235     int y = ay + xy[start].y;
9236
9237     if (!IN_LEV_FIELD(x, y))
9238       return;
9239
9240     if (IS_FREE(x, y) ||
9241         CAN_GROW_INTO(Tile[x][y]) ||
9242         Tile[x][y] == EL_QUICKSAND_EMPTY ||
9243         Tile[x][y] == EL_QUICKSAND_FAST_EMPTY)
9244     {
9245       newax = x;
9246       neway = y;
9247     }
9248
9249     if (newax == ax && neway == ay)
9250       return;
9251   }
9252   else                          // normal or "filled" (BD style) amoeba
9253   {
9254     int start = RND(4);
9255     boolean waiting_for_player = FALSE;
9256
9257     for (i = 0; i < NUM_DIRECTIONS; i++)
9258     {
9259       int j = (start + i) % 4;
9260       int x = ax + xy[j].x;
9261       int y = ay + xy[j].y;
9262
9263       if (!IN_LEV_FIELD(x, y))
9264         continue;
9265
9266       if (IS_FREE(x, y) ||
9267           CAN_GROW_INTO(Tile[x][y]) ||
9268           Tile[x][y] == EL_QUICKSAND_EMPTY ||
9269           Tile[x][y] == EL_QUICKSAND_FAST_EMPTY)
9270       {
9271         newax = x;
9272         neway = y;
9273         break;
9274       }
9275       else if (IS_PLAYER(x, y))
9276         waiting_for_player = TRUE;
9277     }
9278
9279     if (newax == ax && neway == ay)             // amoeba cannot grow
9280     {
9281       if (i == 4 && (!waiting_for_player || element == EL_BD_AMOEBA))
9282       {
9283         Tile[ax][ay] = EL_AMOEBA_DEAD;
9284         TEST_DrawLevelField(ax, ay);
9285         AmoebaCnt[AmoebaNr[ax][ay]]--;
9286
9287         if (AmoebaCnt[AmoebaNr[ax][ay]] <= 0)   // amoeba is completely dead
9288         {
9289           if (element == EL_AMOEBA_FULL)
9290             AmoebaToDiamond(ax, ay);
9291           else if (element == EL_BD_AMOEBA)
9292             AmoebaToDiamondBD(ax, ay, level.amoeba_content);
9293         }
9294       }
9295       return;
9296     }
9297     else if (element == EL_AMOEBA_FULL || element == EL_BD_AMOEBA)
9298     {
9299       // amoeba gets larger by growing in some direction
9300
9301       int new_group_nr = AmoebaNr[ax][ay];
9302
9303 #ifdef DEBUG
9304   if (new_group_nr == 0)
9305   {
9306     Debug("game:playing:AmoebaReproduce", "newax = %d, neway = %d",
9307           newax, neway);
9308     Debug("game:playing:AmoebaReproduce", "This should never happen!");
9309
9310     return;
9311   }
9312 #endif
9313
9314       AmoebaNr[newax][neway] = new_group_nr;
9315       AmoebaCnt[new_group_nr]++;
9316       AmoebaCnt2[new_group_nr]++;
9317
9318       // if amoeba touches other amoeba(s) after growing, unify them
9319       AmoebaMerge(newax, neway);
9320
9321       if (element == EL_BD_AMOEBA && AmoebaCnt2[new_group_nr] >= 200)
9322       {
9323         AmoebaToDiamondBD(newax, neway, EL_BD_ROCK);
9324         return;
9325       }
9326     }
9327   }
9328
9329   if (!can_drop || neway < ay || !IS_FREE(newax, neway) ||
9330       (neway == lev_fieldy - 1 && newax != ax))
9331   {
9332     Tile[newax][neway] = EL_AMOEBA_GROWING;     // creation of new amoeba
9333     Store[newax][neway] = element;
9334   }
9335   else if (neway == ay || element == EL_EMC_DRIPPER)
9336   {
9337     Tile[newax][neway] = EL_AMOEBA_DROP;        // drop left/right of amoeba
9338
9339     PlayLevelSoundAction(newax, neway, ACTION_GROWING);
9340   }
9341   else
9342   {
9343     InitMovingField(ax, ay, MV_DOWN);           // drop dripping from amoeba
9344     Tile[ax][ay] = EL_AMOEBA_DROPPING;
9345     Store[ax][ay] = EL_AMOEBA_DROP;
9346     ContinueMoving(ax, ay);
9347     return;
9348   }
9349
9350   TEST_DrawLevelField(newax, neway);
9351 }
9352
9353 static void Life(int ax, int ay)
9354 {
9355   int x1, y1, x2, y2;
9356   int life_time = 40;
9357   int element = Tile[ax][ay];
9358   int graphic = el2img(element);
9359   int *life_parameter = (element == EL_GAME_OF_LIFE ? level.game_of_life :
9360                          level.biomaze);
9361   boolean changed = FALSE;
9362
9363   if (IS_ANIMATED(graphic))
9364     DrawLevelGraphicAnimationIfNeeded(ax, ay, graphic);
9365
9366   if (Stop[ax][ay])
9367     return;
9368
9369   if (!MovDelay[ax][ay])        // start new "game of life" cycle
9370     MovDelay[ax][ay] = life_time;
9371
9372   if (MovDelay[ax][ay])         // wait some time before next cycle
9373   {
9374     MovDelay[ax][ay]--;
9375     if (MovDelay[ax][ay])
9376       return;
9377   }
9378
9379   for (y1 = -1; y1 < 2; y1++) for (x1 = -1; x1 < 2; x1++)
9380   {
9381     int xx = ax+x1, yy = ay+y1;
9382     int old_element = Tile[xx][yy];
9383     int num_neighbours = 0;
9384
9385     if (!IN_LEV_FIELD(xx, yy))
9386       continue;
9387
9388     for (y2 = -1; y2 < 2; y2++) for (x2 = -1; x2 < 2; x2++)
9389     {
9390       int x = xx+x2, y = yy+y2;
9391
9392       if (!IN_LEV_FIELD(x, y) || (x == xx && y == yy))
9393         continue;
9394
9395       boolean is_player_cell = (element == EL_GAME_OF_LIFE && IS_PLAYER(x, y));
9396       boolean is_neighbour = FALSE;
9397
9398       if (level.use_life_bugs)
9399         is_neighbour =
9400           (((Tile[x][y] == element || is_player_cell) && !Stop[x][y]) ||
9401            (IS_FREE(x, y)                             &&  Stop[x][y]));
9402       else
9403         is_neighbour =
9404           (Last[x][y] == element || is_player_cell);
9405
9406       if (is_neighbour)
9407         num_neighbours++;
9408     }
9409
9410     boolean is_free = FALSE;
9411
9412     if (level.use_life_bugs)
9413       is_free = (IS_FREE(xx, yy));
9414     else
9415       is_free = (IS_FREE(xx, yy) && Last[xx][yy] == EL_EMPTY);
9416
9417     if (xx == ax && yy == ay)           // field in the middle
9418     {
9419       if (num_neighbours < life_parameter[0] ||
9420           num_neighbours > life_parameter[1])
9421       {
9422         Tile[xx][yy] = EL_EMPTY;
9423         if (Tile[xx][yy] != old_element)
9424           TEST_DrawLevelField(xx, yy);
9425         Stop[xx][yy] = TRUE;
9426         changed = TRUE;
9427       }
9428     }
9429     else if (is_free || CAN_GROW_INTO(Tile[xx][yy]))
9430     {                                   // free border field
9431       if (num_neighbours >= life_parameter[2] &&
9432           num_neighbours <= life_parameter[3])
9433       {
9434         Tile[xx][yy] = element;
9435         MovDelay[xx][yy] = (element == EL_GAME_OF_LIFE ? 0 : life_time - 1);
9436         if (Tile[xx][yy] != old_element)
9437           TEST_DrawLevelField(xx, yy);
9438         Stop[xx][yy] = TRUE;
9439         changed = TRUE;
9440       }
9441     }
9442   }
9443
9444   if (changed)
9445     PlayLevelSound(ax, ay, element == EL_BIOMAZE ? SND_BIOMAZE_GROWING :
9446                    SND_GAME_OF_LIFE_GROWING);
9447 }
9448
9449 static void InitRobotWheel(int x, int y)
9450 {
9451   ChangeDelay[x][y] = level.time_wheel * FRAMES_PER_SECOND;
9452 }
9453
9454 static void RunRobotWheel(int x, int y)
9455 {
9456   PlayLevelSound(x, y, SND_ROBOT_WHEEL_ACTIVE);
9457 }
9458
9459 static void StopRobotWheel(int x, int y)
9460 {
9461   if (game.robot_wheel_x == x &&
9462       game.robot_wheel_y == y)
9463   {
9464     game.robot_wheel_x = -1;
9465     game.robot_wheel_y = -1;
9466     game.robot_wheel_active = FALSE;
9467   }
9468 }
9469
9470 static void InitTimegateWheel(int x, int y)
9471 {
9472   ChangeDelay[x][y] = level.time_timegate * FRAMES_PER_SECOND;
9473 }
9474
9475 static void RunTimegateWheel(int x, int y)
9476 {
9477   PlayLevelSound(x, y, SND_CLASS_TIMEGATE_SWITCH_ACTIVE);
9478 }
9479
9480 static void InitMagicBallDelay(int x, int y)
9481 {
9482   ChangeDelay[x][y] = (level.ball_time + 1) * 8 + 1;
9483 }
9484
9485 static void ActivateMagicBall(int bx, int by)
9486 {
9487   int x, y;
9488
9489   if (level.ball_random)
9490   {
9491     int pos_border = RND(8);    // select one of the eight border elements
9492     int pos_content = (pos_border > 3 ? pos_border + 1 : pos_border);
9493     int xx = pos_content % 3;
9494     int yy = pos_content / 3;
9495
9496     x = bx - 1 + xx;
9497     y = by - 1 + yy;
9498
9499     if (IN_LEV_FIELD(x, y) && Tile[x][y] == EL_EMPTY)
9500       CreateField(x, y, level.ball_content[game.ball_content_nr].e[xx][yy]);
9501   }
9502   else
9503   {
9504     for (y = by - 1; y <= by + 1; y++) for (x = bx - 1; x <= bx + 1; x++)
9505     {
9506       int xx = x - bx + 1;
9507       int yy = y - by + 1;
9508
9509       if (IN_LEV_FIELD(x, y) && Tile[x][y] == EL_EMPTY)
9510         CreateField(x, y, level.ball_content[game.ball_content_nr].e[xx][yy]);
9511     }
9512   }
9513
9514   game.ball_content_nr = (game.ball_content_nr + 1) % level.num_ball_contents;
9515 }
9516
9517 static void CheckExit(int x, int y)
9518 {
9519   if (game.gems_still_needed > 0 ||
9520       game.sokoban_fields_still_needed > 0 ||
9521       game.sokoban_objects_still_needed > 0 ||
9522       game.lights_still_needed > 0)
9523   {
9524     int element = Tile[x][y];
9525     int graphic = el2img(element);
9526
9527     if (IS_ANIMATED(graphic))
9528       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
9529
9530     return;
9531   }
9532
9533   // do not re-open exit door closed after last player
9534   if (game.all_players_gone)
9535     return;
9536
9537   Tile[x][y] = EL_EXIT_OPENING;
9538
9539   PlayLevelSoundNearest(x, y, SND_CLASS_EXIT_OPENING);
9540 }
9541
9542 static void CheckExitEM(int x, int y)
9543 {
9544   if (game.gems_still_needed > 0 ||
9545       game.sokoban_fields_still_needed > 0 ||
9546       game.sokoban_objects_still_needed > 0 ||
9547       game.lights_still_needed > 0)
9548   {
9549     int element = Tile[x][y];
9550     int graphic = el2img(element);
9551
9552     if (IS_ANIMATED(graphic))
9553       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
9554
9555     return;
9556   }
9557
9558   // do not re-open exit door closed after last player
9559   if (game.all_players_gone)
9560     return;
9561
9562   Tile[x][y] = EL_EM_EXIT_OPENING;
9563
9564   PlayLevelSoundNearest(x, y, SND_CLASS_EM_EXIT_OPENING);
9565 }
9566
9567 static void CheckExitSteel(int x, int y)
9568 {
9569   if (game.gems_still_needed > 0 ||
9570       game.sokoban_fields_still_needed > 0 ||
9571       game.sokoban_objects_still_needed > 0 ||
9572       game.lights_still_needed > 0)
9573   {
9574     int element = Tile[x][y];
9575     int graphic = el2img(element);
9576
9577     if (IS_ANIMATED(graphic))
9578       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
9579
9580     return;
9581   }
9582
9583   // do not re-open exit door closed after last player
9584   if (game.all_players_gone)
9585     return;
9586
9587   Tile[x][y] = EL_STEEL_EXIT_OPENING;
9588
9589   PlayLevelSoundNearest(x, y, SND_CLASS_STEEL_EXIT_OPENING);
9590 }
9591
9592 static void CheckExitSteelEM(int x, int y)
9593 {
9594   if (game.gems_still_needed > 0 ||
9595       game.sokoban_fields_still_needed > 0 ||
9596       game.sokoban_objects_still_needed > 0 ||
9597       game.lights_still_needed > 0)
9598   {
9599     int element = Tile[x][y];
9600     int graphic = el2img(element);
9601
9602     if (IS_ANIMATED(graphic))
9603       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
9604
9605     return;
9606   }
9607
9608   // do not re-open exit door closed after last player
9609   if (game.all_players_gone)
9610     return;
9611
9612   Tile[x][y] = EL_EM_STEEL_EXIT_OPENING;
9613
9614   PlayLevelSoundNearest(x, y, SND_CLASS_EM_STEEL_EXIT_OPENING);
9615 }
9616
9617 static void CheckExitSP(int x, int y)
9618 {
9619   if (game.gems_still_needed > 0)
9620   {
9621     int element = Tile[x][y];
9622     int graphic = el2img(element);
9623
9624     if (IS_ANIMATED(graphic))
9625       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
9626
9627     return;
9628   }
9629
9630   // do not re-open exit door closed after last player
9631   if (game.all_players_gone)
9632     return;
9633
9634   Tile[x][y] = EL_SP_EXIT_OPENING;
9635
9636   PlayLevelSoundNearest(x, y, SND_CLASS_SP_EXIT_OPENING);
9637 }
9638
9639 static void CloseAllOpenTimegates(void)
9640 {
9641   int x, y;
9642
9643   SCAN_PLAYFIELD(x, y)
9644   {
9645     int element = Tile[x][y];
9646
9647     if (element == EL_TIMEGATE_OPEN || element == EL_TIMEGATE_OPENING)
9648     {
9649       Tile[x][y] = EL_TIMEGATE_CLOSING;
9650
9651       PlayLevelSoundAction(x, y, ACTION_CLOSING);
9652     }
9653   }
9654 }
9655
9656 static void DrawTwinkleOnField(int x, int y)
9657 {
9658   if (!IN_SCR_FIELD(SCREENX(x), SCREENY(y)) || IS_MOVING(x, y))
9659     return;
9660
9661   if (Tile[x][y] == EL_BD_DIAMOND)
9662     return;
9663
9664   if (MovDelay[x][y] == 0)      // next animation frame
9665     MovDelay[x][y] = 11 * !GetSimpleRandom(500);
9666
9667   if (MovDelay[x][y] != 0)      // wait some time before next frame
9668   {
9669     MovDelay[x][y]--;
9670
9671     DrawLevelElementAnimation(x, y, Tile[x][y]);
9672
9673     if (MovDelay[x][y] != 0)
9674     {
9675       int frame = getGraphicAnimationFrame(IMG_TWINKLE_WHITE,
9676                                            10 - MovDelay[x][y]);
9677
9678       DrawGraphicThruMask(SCREENX(x), SCREENY(y), IMG_TWINKLE_WHITE, frame);
9679     }
9680   }
9681 }
9682
9683 static void WallGrowing(int x, int y)
9684 {
9685   int delay = 6;
9686
9687   if (!MovDelay[x][y])          // next animation frame
9688     MovDelay[x][y] = 3 * delay;
9689
9690   if (MovDelay[x][y])           // wait some time before next frame
9691   {
9692     MovDelay[x][y]--;
9693
9694     if (IN_SCR_FIELD(SCREENX(x), SCREENY(y)))
9695     {
9696       int graphic = el_dir2img(Tile[x][y], GfxDir[x][y]);
9697       int frame = getGraphicAnimationFrame(graphic, 17 - MovDelay[x][y]);
9698
9699       DrawLevelGraphic(x, y, graphic, frame);
9700     }
9701
9702     if (!MovDelay[x][y])
9703     {
9704       if (MovDir[x][y] == MV_LEFT)
9705       {
9706         if (IN_LEV_FIELD(x - 1, y) && IS_WALL(Tile[x - 1][y]))
9707           TEST_DrawLevelField(x - 1, y);
9708       }
9709       else if (MovDir[x][y] == MV_RIGHT)
9710       {
9711         if (IN_LEV_FIELD(x + 1, y) && IS_WALL(Tile[x + 1][y]))
9712           TEST_DrawLevelField(x + 1, y);
9713       }
9714       else if (MovDir[x][y] == MV_UP)
9715       {
9716         if (IN_LEV_FIELD(x, y - 1) && IS_WALL(Tile[x][y - 1]))
9717           TEST_DrawLevelField(x, y - 1);
9718       }
9719       else
9720       {
9721         if (IN_LEV_FIELD(x, y + 1) && IS_WALL(Tile[x][y + 1]))
9722           TEST_DrawLevelField(x, y + 1);
9723       }
9724
9725       Tile[x][y] = Store[x][y];
9726       Store[x][y] = 0;
9727       GfxDir[x][y] = MovDir[x][y] = MV_NONE;
9728       TEST_DrawLevelField(x, y);
9729     }
9730   }
9731 }
9732
9733 static void CheckWallGrowing(int ax, int ay)
9734 {
9735   int element = Tile[ax][ay];
9736   int graphic = el2img(element);
9737   boolean free_top    = FALSE;
9738   boolean free_bottom = FALSE;
9739   boolean free_left   = FALSE;
9740   boolean free_right  = FALSE;
9741   boolean stop_top    = FALSE;
9742   boolean stop_bottom = FALSE;
9743   boolean stop_left   = FALSE;
9744   boolean stop_right  = FALSE;
9745   boolean new_wall    = FALSE;
9746
9747   boolean is_steelwall  = (element == EL_EXPANDABLE_STEELWALL_HORIZONTAL ||
9748                            element == EL_EXPANDABLE_STEELWALL_VERTICAL ||
9749                            element == EL_EXPANDABLE_STEELWALL_ANY);
9750
9751   boolean grow_vertical   = (element == EL_EXPANDABLE_WALL_VERTICAL ||
9752                              element == EL_EXPANDABLE_WALL_ANY ||
9753                              element == EL_EXPANDABLE_STEELWALL_VERTICAL ||
9754                              element == EL_EXPANDABLE_STEELWALL_ANY);
9755
9756   boolean grow_horizontal = (element == EL_EXPANDABLE_WALL_HORIZONTAL ||
9757                              element == EL_EXPANDABLE_WALL_ANY ||
9758                              element == EL_EXPANDABLE_WALL ||
9759                              element == EL_BD_EXPANDABLE_WALL ||
9760                              element == EL_EXPANDABLE_STEELWALL_HORIZONTAL ||
9761                              element == EL_EXPANDABLE_STEELWALL_ANY);
9762
9763   boolean stop_vertical   = (element == EL_EXPANDABLE_WALL_VERTICAL ||
9764                              element == EL_EXPANDABLE_STEELWALL_VERTICAL);
9765
9766   boolean stop_horizontal = (element == EL_EXPANDABLE_WALL_HORIZONTAL ||
9767                              element == EL_EXPANDABLE_WALL ||
9768                              element == EL_EXPANDABLE_STEELWALL_HORIZONTAL);
9769
9770   int wall_growing = (is_steelwall ?
9771                       EL_EXPANDABLE_STEELWALL_GROWING :
9772                       EL_EXPANDABLE_WALL_GROWING);
9773
9774   int gfx_wall_growing_up    = (is_steelwall ?
9775                                 IMG_EXPANDABLE_STEELWALL_GROWING_UP :
9776                                 IMG_EXPANDABLE_WALL_GROWING_UP);
9777   int gfx_wall_growing_down  = (is_steelwall ?
9778                                 IMG_EXPANDABLE_STEELWALL_GROWING_DOWN :
9779                                 IMG_EXPANDABLE_WALL_GROWING_DOWN);
9780   int gfx_wall_growing_left  = (is_steelwall ?
9781                                 IMG_EXPANDABLE_STEELWALL_GROWING_LEFT :
9782                                 IMG_EXPANDABLE_WALL_GROWING_LEFT);
9783   int gfx_wall_growing_right = (is_steelwall ?
9784                                 IMG_EXPANDABLE_STEELWALL_GROWING_RIGHT :
9785                                 IMG_EXPANDABLE_WALL_GROWING_RIGHT);
9786
9787   if (IS_ANIMATED(graphic))
9788     DrawLevelGraphicAnimationIfNeeded(ax, ay, graphic);
9789
9790   if (!MovDelay[ax][ay])        // start building new wall
9791     MovDelay[ax][ay] = 6;
9792
9793   if (MovDelay[ax][ay])         // wait some time before building new wall
9794   {
9795     MovDelay[ax][ay]--;
9796     if (MovDelay[ax][ay])
9797       return;
9798   }
9799
9800   if (IN_LEV_FIELD(ax, ay - 1) && IS_FREE(ax, ay - 1))
9801     free_top = TRUE;
9802   if (IN_LEV_FIELD(ax, ay + 1) && IS_FREE(ax, ay + 1))
9803     free_bottom = TRUE;
9804   if (IN_LEV_FIELD(ax - 1, ay) && IS_FREE(ax - 1, ay))
9805     free_left = TRUE;
9806   if (IN_LEV_FIELD(ax + 1, ay) && IS_FREE(ax + 1, ay))
9807     free_right = TRUE;
9808
9809   if (grow_vertical)
9810   {
9811     if (free_top)
9812     {
9813       Tile[ax][ay - 1] = wall_growing;
9814       Store[ax][ay - 1] = element;
9815       GfxDir[ax][ay - 1] = MovDir[ax][ay - 1] = MV_UP;
9816
9817       if (IN_SCR_FIELD(SCREENX(ax), SCREENY(ay - 1)))
9818         DrawLevelGraphic(ax, ay - 1, gfx_wall_growing_up, 0);
9819
9820       new_wall = TRUE;
9821     }
9822
9823     if (free_bottom)
9824     {
9825       Tile[ax][ay + 1] = wall_growing;
9826       Store[ax][ay + 1] = element;
9827       GfxDir[ax][ay + 1] = MovDir[ax][ay + 1] = MV_DOWN;
9828
9829       if (IN_SCR_FIELD(SCREENX(ax), SCREENY(ay + 1)))
9830         DrawLevelGraphic(ax, ay + 1, gfx_wall_growing_down, 0);
9831
9832       new_wall = TRUE;
9833     }
9834   }
9835
9836   if (grow_horizontal)
9837   {
9838     if (free_left)
9839     {
9840       Tile[ax - 1][ay] = wall_growing;
9841       Store[ax - 1][ay] = element;
9842       GfxDir[ax - 1][ay] = MovDir[ax - 1][ay] = MV_LEFT;
9843
9844       if (IN_SCR_FIELD(SCREENX(ax - 1), SCREENY(ay)))
9845         DrawLevelGraphic(ax - 1, ay, gfx_wall_growing_left, 0);
9846
9847       new_wall = TRUE;
9848     }
9849
9850     if (free_right)
9851     {
9852       Tile[ax + 1][ay] = wall_growing;
9853       Store[ax + 1][ay] = element;
9854       GfxDir[ax + 1][ay] = MovDir[ax + 1][ay] = MV_RIGHT;
9855
9856       if (IN_SCR_FIELD(SCREENX(ax + 1), SCREENY(ay)))
9857         DrawLevelGraphic(ax + 1, ay, gfx_wall_growing_right, 0);
9858
9859       new_wall = TRUE;
9860     }
9861   }
9862
9863   if (element == EL_EXPANDABLE_WALL && (free_left || free_right))
9864     TEST_DrawLevelField(ax, ay);
9865
9866   if (!IN_LEV_FIELD(ax, ay - 1) || IS_WALL(Tile[ax][ay - 1]))
9867     stop_top = TRUE;
9868   if (!IN_LEV_FIELD(ax, ay + 1) || IS_WALL(Tile[ax][ay + 1]))
9869     stop_bottom = TRUE;
9870   if (!IN_LEV_FIELD(ax - 1, ay) || IS_WALL(Tile[ax - 1][ay]))
9871     stop_left = TRUE;
9872   if (!IN_LEV_FIELD(ax + 1, ay) || IS_WALL(Tile[ax + 1][ay]))
9873     stop_right = TRUE;
9874
9875   if (((stop_top && stop_bottom) || stop_horizontal) &&
9876       ((stop_left && stop_right) || stop_vertical))
9877     Tile[ax][ay] = (is_steelwall ? EL_STEELWALL : EL_WALL);
9878
9879   if (new_wall)
9880     PlayLevelSoundAction(ax, ay, ACTION_GROWING);
9881 }
9882
9883 static void CheckForDragon(int x, int y)
9884 {
9885   int i, j;
9886   boolean dragon_found = FALSE;
9887   struct XY *xy = xy_topdown;
9888
9889   for (i = 0; i < NUM_DIRECTIONS; i++)
9890   {
9891     for (j = 0; j < 4; j++)
9892     {
9893       int xx = x + j * xy[i].x;
9894       int yy = y + j * xy[i].y;
9895
9896       if (IN_LEV_FIELD(xx, yy) &&
9897           (Tile[xx][yy] == EL_FLAMES || Tile[xx][yy] == EL_DRAGON))
9898       {
9899         if (Tile[xx][yy] == EL_DRAGON)
9900           dragon_found = TRUE;
9901       }
9902       else
9903         break;
9904     }
9905   }
9906
9907   if (!dragon_found)
9908   {
9909     for (i = 0; i < NUM_DIRECTIONS; i++)
9910     {
9911       for (j = 0; j < 3; j++)
9912       {
9913         int xx = x + j * xy[i].x;
9914         int yy = y + j * xy[i].y;
9915
9916         if (IN_LEV_FIELD(xx, yy) && Tile[xx][yy] == EL_FLAMES)
9917         {
9918           Tile[xx][yy] = EL_EMPTY;
9919           TEST_DrawLevelField(xx, yy);
9920         }
9921         else
9922           break;
9923       }
9924     }
9925   }
9926 }
9927
9928 static void InitBuggyBase(int x, int y)
9929 {
9930   int element = Tile[x][y];
9931   int activating_delay = FRAMES_PER_SECOND / 4;
9932
9933   ChangeDelay[x][y] =
9934     (element == EL_SP_BUGGY_BASE ?
9935      2 * FRAMES_PER_SECOND + RND(5 * FRAMES_PER_SECOND) - activating_delay :
9936      element == EL_SP_BUGGY_BASE_ACTIVATING ?
9937      activating_delay :
9938      element == EL_SP_BUGGY_BASE_ACTIVE ?
9939      1 * FRAMES_PER_SECOND + RND(1 * FRAMES_PER_SECOND) : 1);
9940 }
9941
9942 static void WarnBuggyBase(int x, int y)
9943 {
9944   int i;
9945   struct XY *xy = xy_topdown;
9946
9947   for (i = 0; i < NUM_DIRECTIONS; i++)
9948   {
9949     int xx = x + xy[i].x;
9950     int yy = y + xy[i].y;
9951
9952     if (IN_LEV_FIELD(xx, yy) && IS_PLAYER(xx, yy))
9953     {
9954       PlayLevelSound(x, y, SND_SP_BUGGY_BASE_ACTIVE);
9955
9956       break;
9957     }
9958   }
9959 }
9960
9961 static void InitTrap(int x, int y)
9962 {
9963   ChangeDelay[x][y] = 2 * FRAMES_PER_SECOND + RND(5 * FRAMES_PER_SECOND);
9964 }
9965
9966 static void ActivateTrap(int x, int y)
9967 {
9968   PlayLevelSound(x, y, SND_TRAP_ACTIVATING);
9969 }
9970
9971 static void ChangeActiveTrap(int x, int y)
9972 {
9973   int graphic = IMG_TRAP_ACTIVE;
9974
9975   // if new animation frame was drawn, correct crumbled sand border
9976   if (IS_NEW_FRAME(GfxFrame[x][y], graphic))
9977     TEST_DrawLevelFieldCrumbled(x, y);
9978 }
9979
9980 static int getSpecialActionElement(int element, int number, int base_element)
9981 {
9982   return (element != EL_EMPTY ? element :
9983           number != -1 ? base_element + number - 1 :
9984           EL_EMPTY);
9985 }
9986
9987 static int getModifiedActionNumber(int value_old, int operator, int operand,
9988                                    int value_min, int value_max)
9989 {
9990   int value_new = (operator == CA_MODE_SET      ? operand :
9991                    operator == CA_MODE_ADD      ? value_old + operand :
9992                    operator == CA_MODE_SUBTRACT ? value_old - operand :
9993                    operator == CA_MODE_MULTIPLY ? value_old * operand :
9994                    operator == CA_MODE_DIVIDE   ? value_old / MAX(1, operand) :
9995                    operator == CA_MODE_MODULO   ? value_old % MAX(1, operand) :
9996                    value_old);
9997
9998   return (value_new < value_min ? value_min :
9999           value_new > value_max ? value_max :
10000           value_new);
10001 }
10002
10003 static void ExecuteCustomElementAction(int x, int y, int element, int page)
10004 {
10005   struct ElementInfo *ei = &element_info[element];
10006   struct ElementChangeInfo *change = &ei->change_page[page];
10007   int target_element = change->target_element;
10008   int action_type = change->action_type;
10009   int action_mode = change->action_mode;
10010   int action_arg = change->action_arg;
10011   int action_element = change->action_element;
10012   int i;
10013
10014   if (!change->has_action)
10015     return;
10016
10017   // ---------- determine action paramater values -----------------------------
10018
10019   int level_time_value =
10020     (level.time > 0 ? TimeLeft :
10021      TimePlayed);
10022
10023   int action_arg_element_raw =
10024     (action_arg == CA_ARG_PLAYER_TRIGGER  ? change->actual_trigger_player :
10025      action_arg == CA_ARG_ELEMENT_TRIGGER ? change->actual_trigger_element :
10026      action_arg == CA_ARG_ELEMENT_TARGET  ? change->target_element :
10027      action_arg == CA_ARG_ELEMENT_ACTION  ? change->action_element :
10028      action_arg == CA_ARG_INVENTORY_RM_TRIGGER ? change->actual_trigger_element:
10029      action_arg == CA_ARG_INVENTORY_RM_TARGET  ? change->target_element :
10030      action_arg == CA_ARG_INVENTORY_RM_ACTION  ? change->action_element :
10031      EL_EMPTY);
10032   int action_arg_element = GetElementFromGroupElement(action_arg_element_raw);
10033
10034   int action_arg_direction =
10035     (action_arg >= CA_ARG_DIRECTION_LEFT &&
10036      action_arg <= CA_ARG_DIRECTION_DOWN ? action_arg - CA_ARG_DIRECTION :
10037      action_arg == CA_ARG_DIRECTION_TRIGGER ?
10038      change->actual_trigger_side :
10039      action_arg == CA_ARG_DIRECTION_TRIGGER_BACK ?
10040      MV_DIR_OPPOSITE(change->actual_trigger_side) :
10041      MV_NONE);
10042
10043   int action_arg_number_min =
10044     (action_type == CA_SET_PLAYER_SPEED ? STEPSIZE_NOT_MOVING :
10045      CA_ARG_MIN);
10046
10047   int action_arg_number_max =
10048     (action_type == CA_SET_PLAYER_SPEED ? STEPSIZE_EVEN_FASTER :
10049      action_type == CA_SET_LEVEL_GEMS ? 999 :
10050      action_type == CA_SET_LEVEL_TIME ? 9999 :
10051      action_type == CA_SET_LEVEL_SCORE ? 99999 :
10052      action_type == CA_SET_CE_VALUE ? 9999 :
10053      action_type == CA_SET_CE_SCORE ? 9999 :
10054      CA_ARG_MAX);
10055
10056   int action_arg_number_reset =
10057     (action_type == CA_SET_PLAYER_SPEED ? level.initial_player_stepsize[0] :
10058      action_type == CA_SET_LEVEL_GEMS ? level.gems_needed :
10059      action_type == CA_SET_LEVEL_TIME ? level.time :
10060      action_type == CA_SET_LEVEL_SCORE ? 0 :
10061      action_type == CA_SET_CE_VALUE ? GET_NEW_CE_VALUE(element) :
10062      action_type == CA_SET_CE_SCORE ? 0 :
10063      0);
10064
10065   int action_arg_number =
10066     (action_arg <= CA_ARG_MAX ? action_arg :
10067      action_arg >= CA_ARG_SPEED_NOT_MOVING &&
10068      action_arg <= CA_ARG_SPEED_EVEN_FASTER ? (action_arg - CA_ARG_SPEED) :
10069      action_arg == CA_ARG_SPEED_RESET ? action_arg_number_reset :
10070      action_arg == CA_ARG_NUMBER_MIN ? action_arg_number_min :
10071      action_arg == CA_ARG_NUMBER_MAX ? action_arg_number_max :
10072      action_arg == CA_ARG_NUMBER_RESET ? action_arg_number_reset :
10073      action_arg == CA_ARG_NUMBER_CE_VALUE ? CustomValue[x][y] :
10074      action_arg == CA_ARG_NUMBER_CE_SCORE ? ei->collect_score :
10075      action_arg == CA_ARG_NUMBER_CE_DELAY ? GET_CE_DELAY_VALUE(change) :
10076      action_arg == CA_ARG_NUMBER_LEVEL_TIME ? level_time_value :
10077      action_arg == CA_ARG_NUMBER_LEVEL_GEMS ? game.gems_still_needed :
10078      action_arg == CA_ARG_NUMBER_LEVEL_SCORE ? game.score :
10079      action_arg == CA_ARG_ELEMENT_CV_TARGET ? GET_NEW_CE_VALUE(target_element):
10080      action_arg == CA_ARG_ELEMENT_CV_TRIGGER ? change->actual_trigger_ce_value:
10081      action_arg == CA_ARG_ELEMENT_CV_ACTION ? GET_NEW_CE_VALUE(action_element):
10082      action_arg == CA_ARG_ELEMENT_CS_TARGET ? GET_CE_SCORE(target_element) :
10083      action_arg == CA_ARG_ELEMENT_CS_TRIGGER ? change->actual_trigger_ce_score:
10084      action_arg == CA_ARG_ELEMENT_CS_ACTION ? GET_CE_SCORE(action_element) :
10085      action_arg == CA_ARG_ELEMENT_NR_TARGET  ? change->target_element :
10086      action_arg == CA_ARG_ELEMENT_NR_TRIGGER ? change->actual_trigger_element :
10087      action_arg == CA_ARG_ELEMENT_NR_ACTION  ? change->action_element :
10088      -1);
10089
10090   int action_arg_number_old =
10091     (action_type == CA_SET_LEVEL_GEMS ? game.gems_still_needed :
10092      action_type == CA_SET_LEVEL_TIME ? TimeLeft :
10093      action_type == CA_SET_LEVEL_SCORE ? game.score :
10094      action_type == CA_SET_CE_VALUE ? CustomValue[x][y] :
10095      action_type == CA_SET_CE_SCORE ? ei->collect_score :
10096      0);
10097
10098   int action_arg_number_new =
10099     getModifiedActionNumber(action_arg_number_old,
10100                             action_mode, action_arg_number,
10101                             action_arg_number_min, action_arg_number_max);
10102
10103   int trigger_player_bits =
10104     (change->actual_trigger_player_bits != CH_PLAYER_NONE ?
10105      change->actual_trigger_player_bits : change->trigger_player);
10106
10107   int action_arg_player_bits =
10108     (action_arg >= CA_ARG_PLAYER_1 &&
10109      action_arg <= CA_ARG_PLAYER_4 ? action_arg - CA_ARG_PLAYER :
10110      action_arg == CA_ARG_PLAYER_TRIGGER ? trigger_player_bits :
10111      action_arg == CA_ARG_PLAYER_ACTION ? 1 << GET_PLAYER_NR(action_element) :
10112      PLAYER_BITS_ANY);
10113
10114   // ---------- execute action  -----------------------------------------------
10115
10116   switch (action_type)
10117   {
10118     case CA_NO_ACTION:
10119     {
10120       return;
10121     }
10122
10123     // ---------- level actions  ----------------------------------------------
10124
10125     case CA_RESTART_LEVEL:
10126     {
10127       game.restart_level = TRUE;
10128
10129       break;
10130     }
10131
10132     case CA_SHOW_ENVELOPE:
10133     {
10134       int element = getSpecialActionElement(action_arg_element,
10135                                             action_arg_number, EL_ENVELOPE_1);
10136
10137       if (IS_ENVELOPE(element))
10138         local_player->show_envelope = element;
10139
10140       break;
10141     }
10142
10143     case CA_SET_LEVEL_TIME:
10144     {
10145       if (level.time > 0)       // only modify limited time value
10146       {
10147         TimeLeft = action_arg_number_new;
10148
10149         game_panel_controls[GAME_PANEL_TIME].value = TimeLeft;
10150
10151         DisplayGameControlValues();
10152
10153         if (!TimeLeft && game.time_limit)
10154           for (i = 0; i < MAX_PLAYERS; i++)
10155             KillPlayer(&stored_player[i]);
10156       }
10157
10158       break;
10159     }
10160
10161     case CA_SET_LEVEL_SCORE:
10162     {
10163       game.score = action_arg_number_new;
10164
10165       game_panel_controls[GAME_PANEL_SCORE].value = game.score;
10166
10167       DisplayGameControlValues();
10168
10169       break;
10170     }
10171
10172     case CA_SET_LEVEL_GEMS:
10173     {
10174       game.gems_still_needed = action_arg_number_new;
10175
10176       game.snapshot.collected_item = TRUE;
10177
10178       game_panel_controls[GAME_PANEL_GEMS].value = game.gems_still_needed;
10179
10180       DisplayGameControlValues();
10181
10182       break;
10183     }
10184
10185     case CA_SET_LEVEL_WIND:
10186     {
10187       game.wind_direction = action_arg_direction;
10188
10189       break;
10190     }
10191
10192     case CA_SET_LEVEL_RANDOM_SEED:
10193     {
10194       // ensure that setting a new random seed while playing is predictable
10195       InitRND(action_arg_number_new ? action_arg_number_new : RND(1000000) + 1);
10196
10197       break;
10198     }
10199
10200     // ---------- player actions  ---------------------------------------------
10201
10202     case CA_MOVE_PLAYER:
10203     case CA_MOVE_PLAYER_NEW:
10204     {
10205       // automatically move to the next field in specified direction
10206       for (i = 0; i < MAX_PLAYERS; i++)
10207         if (trigger_player_bits & (1 << i))
10208           if (action_type == CA_MOVE_PLAYER ||
10209               stored_player[i].MovPos == 0)
10210             stored_player[i].programmed_action = action_arg_direction;
10211
10212       break;
10213     }
10214
10215     case CA_EXIT_PLAYER:
10216     {
10217       for (i = 0; i < MAX_PLAYERS; i++)
10218         if (action_arg_player_bits & (1 << i))
10219           ExitPlayer(&stored_player[i]);
10220
10221       if (game.players_still_needed == 0)
10222         LevelSolved();
10223
10224       break;
10225     }
10226
10227     case CA_KILL_PLAYER:
10228     {
10229       for (i = 0; i < MAX_PLAYERS; i++)
10230         if (action_arg_player_bits & (1 << i))
10231           KillPlayer(&stored_player[i]);
10232
10233       break;
10234     }
10235
10236     case CA_SET_PLAYER_KEYS:
10237     {
10238       int key_state = (action_mode == CA_MODE_ADD ? TRUE : FALSE);
10239       int element = getSpecialActionElement(action_arg_element,
10240                                             action_arg_number, EL_KEY_1);
10241
10242       if (IS_KEY(element))
10243       {
10244         for (i = 0; i < MAX_PLAYERS; i++)
10245         {
10246           if (trigger_player_bits & (1 << i))
10247           {
10248             stored_player[i].key[KEY_NR(element)] = key_state;
10249
10250             DrawGameDoorValues();
10251           }
10252         }
10253       }
10254
10255       break;
10256     }
10257
10258     case CA_SET_PLAYER_SPEED:
10259     {
10260       for (i = 0; i < MAX_PLAYERS; i++)
10261       {
10262         if (trigger_player_bits & (1 << i))
10263         {
10264           int move_stepsize = TILEX / stored_player[i].move_delay_value;
10265
10266           if (action_arg == CA_ARG_SPEED_FASTER &&
10267               stored_player[i].cannot_move)
10268           {
10269             action_arg_number = STEPSIZE_VERY_SLOW;
10270           }
10271           else if (action_arg == CA_ARG_SPEED_SLOWER ||
10272                    action_arg == CA_ARG_SPEED_FASTER)
10273           {
10274             action_arg_number = 2;
10275             action_mode = (action_arg == CA_ARG_SPEED_SLOWER ? CA_MODE_DIVIDE :
10276                            CA_MODE_MULTIPLY);
10277           }
10278           else if (action_arg == CA_ARG_NUMBER_RESET)
10279           {
10280             action_arg_number = level.initial_player_stepsize[i];
10281           }
10282
10283           move_stepsize =
10284             getModifiedActionNumber(move_stepsize,
10285                                     action_mode,
10286                                     action_arg_number,
10287                                     action_arg_number_min,
10288                                     action_arg_number_max);
10289
10290           SetPlayerMoveSpeed(&stored_player[i], move_stepsize, FALSE);
10291         }
10292       }
10293
10294       break;
10295     }
10296
10297     case CA_SET_PLAYER_SHIELD:
10298     {
10299       for (i = 0; i < MAX_PLAYERS; i++)
10300       {
10301         if (trigger_player_bits & (1 << i))
10302         {
10303           if (action_arg == CA_ARG_SHIELD_OFF)
10304           {
10305             stored_player[i].shield_normal_time_left = 0;
10306             stored_player[i].shield_deadly_time_left = 0;
10307           }
10308           else if (action_arg == CA_ARG_SHIELD_NORMAL)
10309           {
10310             stored_player[i].shield_normal_time_left = 999999;
10311           }
10312           else if (action_arg == CA_ARG_SHIELD_DEADLY)
10313           {
10314             stored_player[i].shield_normal_time_left = 999999;
10315             stored_player[i].shield_deadly_time_left = 999999;
10316           }
10317         }
10318       }
10319
10320       break;
10321     }
10322
10323     case CA_SET_PLAYER_GRAVITY:
10324     {
10325       for (i = 0; i < MAX_PLAYERS; i++)
10326       {
10327         if (trigger_player_bits & (1 << i))
10328         {
10329           stored_player[i].gravity =
10330             (action_arg == CA_ARG_GRAVITY_OFF    ? FALSE                     :
10331              action_arg == CA_ARG_GRAVITY_ON     ? TRUE                      :
10332              action_arg == CA_ARG_GRAVITY_TOGGLE ? !stored_player[i].gravity :
10333              stored_player[i].gravity);
10334         }
10335       }
10336
10337       break;
10338     }
10339
10340     case CA_SET_PLAYER_ARTWORK:
10341     {
10342       for (i = 0; i < MAX_PLAYERS; i++)
10343       {
10344         if (trigger_player_bits & (1 << i))
10345         {
10346           int artwork_element = action_arg_element;
10347
10348           if (action_arg == CA_ARG_ELEMENT_RESET)
10349             artwork_element =
10350               (level.use_artwork_element[i] ? level.artwork_element[i] :
10351                stored_player[i].element_nr);
10352
10353           if (stored_player[i].artwork_element != artwork_element)
10354             stored_player[i].Frame = 0;
10355
10356           stored_player[i].artwork_element = artwork_element;
10357
10358           SetPlayerWaiting(&stored_player[i], FALSE);
10359
10360           // set number of special actions for bored and sleeping animation
10361           stored_player[i].num_special_action_bored =
10362             get_num_special_action(artwork_element,
10363                                    ACTION_BORING_1, ACTION_BORING_LAST);
10364           stored_player[i].num_special_action_sleeping =
10365             get_num_special_action(artwork_element,
10366                                    ACTION_SLEEPING_1, ACTION_SLEEPING_LAST);
10367         }
10368       }
10369
10370       break;
10371     }
10372
10373     case CA_SET_PLAYER_INVENTORY:
10374     {
10375       for (i = 0; i < MAX_PLAYERS; i++)
10376       {
10377         struct PlayerInfo *player = &stored_player[i];
10378         int j, k;
10379
10380         if (trigger_player_bits & (1 << i))
10381         {
10382           int inventory_element = action_arg_element;
10383
10384           if (action_arg == CA_ARG_ELEMENT_TARGET ||
10385               action_arg == CA_ARG_ELEMENT_TRIGGER ||
10386               action_arg == CA_ARG_ELEMENT_ACTION)
10387           {
10388             int element = inventory_element;
10389             int collect_count = element_info[element].collect_count_initial;
10390
10391             if (!IS_CUSTOM_ELEMENT(element))
10392               collect_count = 1;
10393
10394             if (collect_count == 0)
10395               player->inventory_infinite_element = element;
10396             else
10397               for (k = 0; k < collect_count; k++)
10398                 if (player->inventory_size < MAX_INVENTORY_SIZE)
10399                   player->inventory_element[player->inventory_size++] =
10400                     element;
10401           }
10402           else if (action_arg == CA_ARG_INVENTORY_RM_TARGET ||
10403                    action_arg == CA_ARG_INVENTORY_RM_TRIGGER ||
10404                    action_arg == CA_ARG_INVENTORY_RM_ACTION)
10405           {
10406             if (player->inventory_infinite_element != EL_UNDEFINED &&
10407                 IS_EQUAL_OR_IN_GROUP(player->inventory_infinite_element,
10408                                      action_arg_element_raw))
10409               player->inventory_infinite_element = EL_UNDEFINED;
10410
10411             for (k = 0, j = 0; j < player->inventory_size; j++)
10412             {
10413               if (!IS_EQUAL_OR_IN_GROUP(player->inventory_element[j],
10414                                         action_arg_element_raw))
10415                 player->inventory_element[k++] = player->inventory_element[j];
10416             }
10417
10418             player->inventory_size = k;
10419           }
10420           else if (action_arg == CA_ARG_INVENTORY_RM_FIRST)
10421           {
10422             if (player->inventory_size > 0)
10423             {
10424               for (j = 0; j < player->inventory_size - 1; j++)
10425                 player->inventory_element[j] = player->inventory_element[j + 1];
10426
10427               player->inventory_size--;
10428             }
10429           }
10430           else if (action_arg == CA_ARG_INVENTORY_RM_LAST)
10431           {
10432             if (player->inventory_size > 0)
10433               player->inventory_size--;
10434           }
10435           else if (action_arg == CA_ARG_INVENTORY_RM_ALL)
10436           {
10437             player->inventory_infinite_element = EL_UNDEFINED;
10438             player->inventory_size = 0;
10439           }
10440           else if (action_arg == CA_ARG_INVENTORY_RESET)
10441           {
10442             player->inventory_infinite_element = EL_UNDEFINED;
10443             player->inventory_size = 0;
10444
10445             if (level.use_initial_inventory[i])
10446             {
10447               for (j = 0; j < level.initial_inventory_size[i]; j++)
10448               {
10449                 int element = level.initial_inventory_content[i][j];
10450                 int collect_count = element_info[element].collect_count_initial;
10451
10452                 if (!IS_CUSTOM_ELEMENT(element))
10453                   collect_count = 1;
10454
10455                 if (collect_count == 0)
10456                   player->inventory_infinite_element = element;
10457                 else
10458                   for (k = 0; k < collect_count; k++)
10459                     if (player->inventory_size < MAX_INVENTORY_SIZE)
10460                       player->inventory_element[player->inventory_size++] =
10461                         element;
10462               }
10463             }
10464           }
10465         }
10466       }
10467
10468       break;
10469     }
10470
10471     // ---------- CE actions  -------------------------------------------------
10472
10473     case CA_SET_CE_VALUE:
10474     {
10475       int last_ce_value = CustomValue[x][y];
10476
10477       CustomValue[x][y] = action_arg_number_new;
10478
10479       if (CustomValue[x][y] != last_ce_value)
10480       {
10481         CheckElementChange(x, y, element, EL_UNDEFINED, CE_VALUE_CHANGES);
10482         CheckTriggeredElementChange(x, y, element, CE_VALUE_CHANGES_OF_X);
10483
10484         if (CustomValue[x][y] == 0)
10485         {
10486           // reset change counter (else CE_VALUE_GETS_ZERO would not work)
10487           ChangeCount[x][y] = 0;        // allow at least one more change
10488
10489           CheckElementChange(x, y, element, EL_UNDEFINED, CE_VALUE_GETS_ZERO);
10490           CheckTriggeredElementChange(x, y, element, CE_VALUE_GETS_ZERO_OF_X);
10491         }
10492       }
10493
10494       break;
10495     }
10496
10497     case CA_SET_CE_SCORE:
10498     {
10499       int last_ce_score = ei->collect_score;
10500
10501       ei->collect_score = action_arg_number_new;
10502
10503       if (ei->collect_score != last_ce_score)
10504       {
10505         CheckElementChange(x, y, element, EL_UNDEFINED, CE_SCORE_CHANGES);
10506         CheckTriggeredElementChange(x, y, element, CE_SCORE_CHANGES_OF_X);
10507
10508         if (ei->collect_score == 0)
10509         {
10510           int xx, yy;
10511
10512           // reset change counter (else CE_SCORE_GETS_ZERO would not work)
10513           ChangeCount[x][y] = 0;        // allow at least one more change
10514
10515           CheckElementChange(x, y, element, EL_UNDEFINED, CE_SCORE_GETS_ZERO);
10516           CheckTriggeredElementChange(x, y, element, CE_SCORE_GETS_ZERO_OF_X);
10517
10518           /*
10519             This is a very special case that seems to be a mixture between
10520             CheckElementChange() and CheckTriggeredElementChange(): while
10521             the first one only affects single elements that are triggered
10522             directly, the second one affects multiple elements in the playfield
10523             that are triggered indirectly by another element. This is a third
10524             case: Changing the CE score always affects multiple identical CEs,
10525             so every affected CE must be checked, not only the single CE for
10526             which the CE score was changed in the first place (as every instance
10527             of that CE shares the same CE score, and therefore also can change)!
10528           */
10529           SCAN_PLAYFIELD(xx, yy)
10530           {
10531             if (Tile[xx][yy] == element)
10532               CheckElementChange(xx, yy, element, EL_UNDEFINED,
10533                                  CE_SCORE_GETS_ZERO);
10534           }
10535         }
10536       }
10537
10538       break;
10539     }
10540
10541     case CA_SET_CE_ARTWORK:
10542     {
10543       int artwork_element = action_arg_element;
10544       boolean reset_frame = FALSE;
10545       int xx, yy;
10546
10547       if (action_arg == CA_ARG_ELEMENT_RESET)
10548         artwork_element = (ei->use_gfx_element ? ei->gfx_element_initial :
10549                            element);
10550
10551       if (ei->gfx_element != artwork_element)
10552         reset_frame = TRUE;
10553
10554       ei->gfx_element = artwork_element;
10555
10556       SCAN_PLAYFIELD(xx, yy)
10557       {
10558         if (Tile[xx][yy] == element)
10559         {
10560           if (reset_frame)
10561           {
10562             ResetGfxAnimation(xx, yy);
10563             ResetRandomAnimationValue(xx, yy);
10564           }
10565
10566           TEST_DrawLevelField(xx, yy);
10567         }
10568       }
10569
10570       break;
10571     }
10572
10573     // ---------- engine actions  ---------------------------------------------
10574
10575     case CA_SET_ENGINE_SCAN_MODE:
10576     {
10577       InitPlayfieldScanMode(action_arg);
10578
10579       break;
10580     }
10581
10582     default:
10583       break;
10584   }
10585 }
10586
10587 static void CreateFieldExt(int x, int y, int element, boolean is_change)
10588 {
10589   int old_element = Tile[x][y];
10590   int new_element = GetElementFromGroupElement(element);
10591   int previous_move_direction = MovDir[x][y];
10592   int last_ce_value = CustomValue[x][y];
10593   boolean player_explosion_protected = PLAYER_EXPLOSION_PROTECTED(x, y);
10594   boolean new_element_is_player = IS_PLAYER_ELEMENT(new_element);
10595   boolean add_player_onto_element = (new_element_is_player &&
10596                                      new_element != EL_SOKOBAN_FIELD_PLAYER &&
10597                                      IS_WALKABLE(old_element));
10598
10599   if (!add_player_onto_element)
10600   {
10601     if (IS_MOVING(x, y) || IS_BLOCKED(x, y))
10602       RemoveMovingField(x, y);
10603     else
10604       RemoveField(x, y);
10605
10606     Tile[x][y] = new_element;
10607
10608     if (element_info[new_element].move_direction_initial == MV_START_PREVIOUS)
10609       MovDir[x][y] = previous_move_direction;
10610
10611     if (element_info[new_element].use_last_ce_value)
10612       CustomValue[x][y] = last_ce_value;
10613
10614     InitField_WithBug1(x, y, FALSE);
10615
10616     new_element = Tile[x][y];   // element may have changed
10617
10618     ResetGfxAnimation(x, y);
10619     ResetRandomAnimationValue(x, y);
10620
10621     TEST_DrawLevelField(x, y);
10622
10623     if (GFX_CRUMBLED(new_element))
10624       TEST_DrawLevelFieldCrumbledNeighbours(x, y);
10625   }
10626
10627   // check if element under the player changes from accessible to unaccessible
10628   // (needed for special case of dropping element which then changes)
10629   // (must be checked after creating new element for walkable group elements)
10630   if (IS_PLAYER(x, y) && !player_explosion_protected &&
10631       IS_ACCESSIBLE(old_element) && !IS_ACCESSIBLE(new_element))
10632   {
10633     Bang(x, y);
10634
10635     return;
10636   }
10637
10638   // "ChangeCount" not set yet to allow "entered by player" change one time
10639   if (new_element_is_player)
10640     RelocatePlayer(x, y, new_element);
10641
10642   if (is_change)
10643     ChangeCount[x][y]++;        // count number of changes in the same frame
10644
10645   TestIfBadThingTouchesPlayer(x, y);
10646   TestIfPlayerTouchesCustomElement(x, y);
10647   TestIfElementTouchesCustomElement(x, y);
10648 }
10649
10650 static void CreateField(int x, int y, int element)
10651 {
10652   CreateFieldExt(x, y, element, FALSE);
10653 }
10654
10655 static void CreateElementFromChange(int x, int y, int element)
10656 {
10657   element = GET_VALID_RUNTIME_ELEMENT(element);
10658
10659   if (game.engine_version >= VERSION_IDENT(3,2,0,7))
10660   {
10661     int old_element = Tile[x][y];
10662
10663     // prevent changed element from moving in same engine frame
10664     // unless both old and new element can either fall or move
10665     if ((!CAN_FALL(old_element) || !CAN_FALL(element)) &&
10666         (!CAN_MOVE(old_element) || !CAN_MOVE(element)))
10667       Stop[x][y] = TRUE;
10668   }
10669
10670   CreateFieldExt(x, y, element, TRUE);
10671 }
10672
10673 static boolean ChangeElement(int x, int y, int element, int page)
10674 {
10675   struct ElementInfo *ei = &element_info[element];
10676   struct ElementChangeInfo *change = &ei->change_page[page];
10677   int ce_value = CustomValue[x][y];
10678   int ce_score = ei->collect_score;
10679   int target_element;
10680   int old_element = Tile[x][y];
10681
10682   // always use default change event to prevent running into a loop
10683   if (ChangeEvent[x][y] == -1)
10684     ChangeEvent[x][y] = CE_DELAY;
10685
10686   if (ChangeEvent[x][y] == CE_DELAY)
10687   {
10688     // reset actual trigger element, trigger player and action element
10689     change->actual_trigger_element = EL_EMPTY;
10690     change->actual_trigger_player = EL_EMPTY;
10691     change->actual_trigger_player_bits = CH_PLAYER_NONE;
10692     change->actual_trigger_side = CH_SIDE_NONE;
10693     change->actual_trigger_ce_value = 0;
10694     change->actual_trigger_ce_score = 0;
10695   }
10696
10697   // do not change elements more than a specified maximum number of changes
10698   if (ChangeCount[x][y] >= game.max_num_changes_per_frame)
10699     return FALSE;
10700
10701   ChangeCount[x][y]++;          // count number of changes in the same frame
10702
10703   if (change->explode)
10704   {
10705     Bang(x, y);
10706
10707     return TRUE;
10708   }
10709
10710   if (change->use_target_content)
10711   {
10712     boolean complete_replace = TRUE;
10713     boolean can_replace[3][3];
10714     int xx, yy;
10715
10716     for (yy = 0; yy < 3; yy++) for (xx = 0; xx < 3 ; xx++)
10717     {
10718       boolean is_empty;
10719       boolean is_walkable;
10720       boolean is_diggable;
10721       boolean is_collectible;
10722       boolean is_removable;
10723       boolean is_destructible;
10724       int ex = x + xx - 1;
10725       int ey = y + yy - 1;
10726       int content_element = change->target_content.e[xx][yy];
10727       int e;
10728
10729       can_replace[xx][yy] = TRUE;
10730
10731       if (ex == x && ey == y)   // do not check changing element itself
10732         continue;
10733
10734       if (content_element == EL_EMPTY_SPACE)
10735       {
10736         can_replace[xx][yy] = FALSE;    // do not replace border with space
10737
10738         continue;
10739       }
10740
10741       if (!IN_LEV_FIELD(ex, ey))
10742       {
10743         can_replace[xx][yy] = FALSE;
10744         complete_replace = FALSE;
10745
10746         continue;
10747       }
10748
10749       e = Tile[ex][ey];
10750
10751       if (IS_MOVING(ex, ey) || IS_BLOCKED(ex, ey))
10752         e = MovingOrBlocked2Element(ex, ey);
10753
10754       is_empty = (IS_FREE(ex, ey) ||
10755                   (IS_FREE_OR_PLAYER(ex, ey) && IS_WALKABLE(content_element)));
10756
10757       is_walkable     = (is_empty || IS_WALKABLE(e));
10758       is_diggable     = (is_empty || IS_DIGGABLE(e));
10759       is_collectible  = (is_empty || IS_COLLECTIBLE(e));
10760       is_destructible = (is_empty || !IS_INDESTRUCTIBLE(e));
10761       is_removable    = (is_diggable || is_collectible);
10762
10763       can_replace[xx][yy] =
10764         (((change->replace_when == CP_WHEN_EMPTY        && is_empty) ||
10765           (change->replace_when == CP_WHEN_WALKABLE     && is_walkable) ||
10766           (change->replace_when == CP_WHEN_DIGGABLE     && is_diggable) ||
10767           (change->replace_when == CP_WHEN_COLLECTIBLE  && is_collectible) ||
10768           (change->replace_when == CP_WHEN_REMOVABLE    && is_removable) ||
10769           (change->replace_when == CP_WHEN_DESTRUCTIBLE && is_destructible)) &&
10770          !(IS_PLAYER(ex, ey) && IS_PLAYER_ELEMENT(content_element)));
10771
10772       if (!can_replace[xx][yy])
10773         complete_replace = FALSE;
10774     }
10775
10776     if (!change->only_if_complete || complete_replace)
10777     {
10778       boolean something_has_changed = FALSE;
10779
10780       if (change->only_if_complete && change->use_random_replace &&
10781           RND(100) < change->random_percentage)
10782         return FALSE;
10783
10784       for (yy = 0; yy < 3; yy++) for (xx = 0; xx < 3 ; xx++)
10785       {
10786         int ex = x + xx - 1;
10787         int ey = y + yy - 1;
10788         int content_element;
10789
10790         if (can_replace[xx][yy] && (!change->use_random_replace ||
10791                                     RND(100) < change->random_percentage))
10792         {
10793           if (IS_MOVING(ex, ey) || IS_BLOCKED(ex, ey))
10794             RemoveMovingField(ex, ey);
10795
10796           ChangeEvent[ex][ey] = ChangeEvent[x][y];
10797
10798           content_element = change->target_content.e[xx][yy];
10799           target_element = GET_TARGET_ELEMENT(element, content_element, change,
10800                                               ce_value, ce_score);
10801
10802           CreateElementFromChange(ex, ey, target_element);
10803
10804           something_has_changed = TRUE;
10805
10806           // for symmetry reasons, freeze newly created border elements
10807           if (ex != x || ey != y)
10808             Stop[ex][ey] = TRUE;        // no more moving in this frame
10809         }
10810       }
10811
10812       if (something_has_changed)
10813       {
10814         PlayLevelSoundElementAction(x, y, element, ACTION_CHANGING);
10815         PlayLevelSoundElementAction(x, y, element, ACTION_PAGE_1 + page);
10816       }
10817     }
10818   }
10819   else
10820   {
10821     target_element = GET_TARGET_ELEMENT(element, change->target_element, change,
10822                                         ce_value, ce_score);
10823
10824     if (element == EL_DIAGONAL_GROWING ||
10825         element == EL_DIAGONAL_SHRINKING)
10826     {
10827       target_element = Store[x][y];
10828
10829       Store[x][y] = EL_EMPTY;
10830     }
10831
10832     // special case: element changes to player (and may be kept if walkable)
10833     if (IS_PLAYER_ELEMENT(target_element) && !level.keep_walkable_ce)
10834       CreateElementFromChange(x, y, EL_EMPTY);
10835
10836     CreateElementFromChange(x, y, target_element);
10837
10838     PlayLevelSoundElementAction(x, y, element, ACTION_CHANGING);
10839     PlayLevelSoundElementAction(x, y, element, ACTION_PAGE_1 + page);
10840   }
10841
10842   // this uses direct change before indirect change
10843   CheckTriggeredElementChangeByPage(x, y, old_element, CE_CHANGE_OF_X, page);
10844
10845   return TRUE;
10846 }
10847
10848 static void HandleElementChange(int x, int y, int page)
10849 {
10850   int element = MovingOrBlocked2Element(x, y);
10851   struct ElementInfo *ei = &element_info[element];
10852   struct ElementChangeInfo *change = &ei->change_page[page];
10853   boolean handle_action_before_change = FALSE;
10854
10855 #ifdef DEBUG
10856   if (!CAN_CHANGE_OR_HAS_ACTION(element) &&
10857       !CAN_CHANGE_OR_HAS_ACTION(Back[x][y]))
10858   {
10859     Debug("game:playing:HandleElementChange", "%d,%d: element = %d ('%s')",
10860           x, y, element, element_info[element].token_name);
10861     Debug("game:playing:HandleElementChange", "This should never happen!");
10862   }
10863 #endif
10864
10865   // this can happen with classic bombs on walkable, changing elements
10866   if (!CAN_CHANGE_OR_HAS_ACTION(element))
10867   {
10868     return;
10869   }
10870
10871   if (ChangeDelay[x][y] == 0)           // initialize element change
10872   {
10873     ChangeDelay[x][y] = GET_CHANGE_DELAY(change) + 1;
10874
10875     if (change->can_change)
10876     {
10877       // !!! not clear why graphic animation should be reset at all here !!!
10878       // !!! UPDATE: but is needed for correct Snake Bite tail animation !!!
10879       // !!! SOLUTION: do not reset if graphics engine set to 4 or above !!!
10880
10881       /*
10882         GRAPHICAL BUG ADDRESSED BY CHECKING GRAPHICS ENGINE VERSION:
10883
10884         When using an animation frame delay of 1 (this only happens with
10885         "sp_zonk.moving.left/right" in the classic graphics), the default
10886         (non-moving) animation shows wrong animation frames (while the
10887         moving animation, like "sp_zonk.moving.left/right", is correct,
10888         so this graphical bug never shows up with the classic graphics).
10889         For an animation with 4 frames, this causes wrong frames 0,0,1,2
10890         be drawn instead of the correct frames 0,1,2,3. This is caused by
10891         "GfxFrame[][]" being reset *twice* (in two successive frames) after
10892         an element change: First when the change delay ("ChangeDelay[][]")
10893         counter has reached zero after decrementing, then a second time in
10894         the next frame (after "GfxFrame[][]" was already incremented) when
10895         "ChangeDelay[][]" is reset to the initial delay value again.
10896
10897         This causes frame 0 to be drawn twice, while the last frame won't
10898         be drawn anymore, resulting in the wrong frame sequence 0,0,1,2.
10899
10900         As some animations may already be cleverly designed around this bug
10901         (at least the "Snake Bite" snake tail animation does this), it cannot
10902         simply be fixed here without breaking such existing animations.
10903         Unfortunately, it cannot easily be detected if a graphics set was
10904         designed "before" or "after" the bug was fixed. As a workaround,
10905         a new graphics set option "game.graphics_engine_version" was added
10906         to be able to specify the game's major release version for which the
10907         graphics set was designed, which can then be used to decide if the
10908         bugfix should be used (version 4 and above) or not (version 3 or
10909         below, or if no version was specified at all, as with old sets).
10910
10911         (The wrong/fixed animation frames can be tested with the test level set
10912         "test_gfxframe" and level "000", which contains a specially prepared
10913         custom element at level position (x/y) == (11/9) which uses the zonk
10914         animation mentioned above. Using "game.graphics_engine_version: 4"
10915         fixes the wrong animation frames, showing the correct frames 0,1,2,3.
10916         This can also be seen from the debug output for this test element.)
10917       */
10918
10919       // when a custom element is about to change (for example by change delay),
10920       // do not reset graphic animation when the custom element is moving
10921       if (game.graphics_engine_version < 4 &&
10922           !IS_MOVING(x, y))
10923       {
10924         ResetGfxAnimation(x, y);
10925         ResetRandomAnimationValue(x, y);
10926       }
10927
10928       if (change->pre_change_function)
10929         change->pre_change_function(x, y);
10930     }
10931   }
10932
10933   ChangeDelay[x][y]--;
10934
10935   if (ChangeDelay[x][y] != 0)           // continue element change
10936   {
10937     if (change->can_change)
10938     {
10939       int graphic = el_act_dir2img(element, GfxAction[x][y], GfxDir[x][y]);
10940
10941       if (IS_ANIMATED(graphic))
10942         DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
10943
10944       if (change->change_function)
10945         change->change_function(x, y);
10946     }
10947   }
10948   else                                  // finish element change
10949   {
10950     if (ChangePage[x][y] != -1)         // remember page from delayed change
10951     {
10952       page = ChangePage[x][y];
10953       ChangePage[x][y] = -1;
10954
10955       change = &ei->change_page[page];
10956     }
10957
10958     if (IS_MOVING(x, y))                // never change a running system ;-)
10959     {
10960       ChangeDelay[x][y] = 1;            // try change after next move step
10961       ChangePage[x][y] = page;          // remember page to use for change
10962
10963       return;
10964     }
10965
10966     // special case: set new level random seed before changing element
10967     if (change->has_action && change->action_type == CA_SET_LEVEL_RANDOM_SEED)
10968       handle_action_before_change = TRUE;
10969
10970     if (change->has_action && handle_action_before_change)
10971       ExecuteCustomElementAction(x, y, element, page);
10972
10973     if (change->can_change)
10974     {
10975       if (ChangeElement(x, y, element, page))
10976       {
10977         if (change->post_change_function)
10978           change->post_change_function(x, y);
10979       }
10980     }
10981
10982     if (change->has_action && !handle_action_before_change)
10983       ExecuteCustomElementAction(x, y, element, page);
10984   }
10985 }
10986
10987 static boolean CheckTriggeredElementChangeExt(int trigger_x, int trigger_y,
10988                                               int trigger_element,
10989                                               int trigger_event,
10990                                               int trigger_player,
10991                                               int trigger_side,
10992                                               int trigger_page)
10993 {
10994   boolean change_done_any = FALSE;
10995   int trigger_page_bits = (trigger_page < 0 ? CH_PAGE_ANY : 1 << trigger_page);
10996   int i;
10997
10998   if (!(trigger_events[trigger_element][trigger_event]))
10999     return FALSE;
11000
11001   RECURSION_LOOP_DETECTION_START(trigger_element, FALSE);
11002
11003   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
11004   {
11005     int element = EL_CUSTOM_START + i;
11006     boolean change_done = FALSE;
11007     int p;
11008
11009     if (!CAN_CHANGE_OR_HAS_ACTION(element) ||
11010         !HAS_ANY_CHANGE_EVENT(element, trigger_event))
11011       continue;
11012
11013     for (p = 0; p < element_info[element].num_change_pages; p++)
11014     {
11015       struct ElementChangeInfo *change = &element_info[element].change_page[p];
11016
11017       if (change->can_change_or_has_action &&
11018           change->has_event[trigger_event] &&
11019           change->trigger_side & trigger_side &&
11020           change->trigger_player & trigger_player &&
11021           change->trigger_page & trigger_page_bits &&
11022           IS_EQUAL_OR_IN_GROUP(trigger_element, change->trigger_element))
11023       {
11024         change->actual_trigger_element = trigger_element;
11025         change->actual_trigger_player = GET_PLAYER_FROM_BITS(trigger_player);
11026         change->actual_trigger_player_bits = trigger_player;
11027         change->actual_trigger_side = trigger_side;
11028         change->actual_trigger_ce_value = CustomValue[trigger_x][trigger_y];
11029         change->actual_trigger_ce_score = GET_CE_SCORE(trigger_element);
11030
11031         if ((change->can_change && !change_done) || change->has_action)
11032         {
11033           int x, y;
11034
11035           SCAN_PLAYFIELD(x, y)
11036           {
11037             if (Tile[x][y] == element)
11038             {
11039               if (change->can_change && !change_done)
11040               {
11041                 // if element already changed in this frame, not only prevent
11042                 // another element change (checked in ChangeElement()), but
11043                 // also prevent additional element actions for this element
11044
11045                 if (ChangeCount[x][y] >= game.max_num_changes_per_frame &&
11046                     !level.use_action_after_change_bug)
11047                   continue;
11048
11049                 ChangeDelay[x][y] = 1;
11050                 ChangeEvent[x][y] = trigger_event;
11051
11052                 HandleElementChange(x, y, p);
11053               }
11054               else if (change->has_action)
11055               {
11056                 // if element already changed in this frame, not only prevent
11057                 // another element change (checked in ChangeElement()), but
11058                 // also prevent additional element actions for this element
11059
11060                 if (ChangeCount[x][y] >= game.max_num_changes_per_frame &&
11061                     !level.use_action_after_change_bug)
11062                   continue;
11063
11064                 ExecuteCustomElementAction(x, y, element, p);
11065                 PlayLevelSoundElementAction(x, y, element, ACTION_PAGE_1 + p);
11066               }
11067             }
11068           }
11069
11070           if (change->can_change)
11071           {
11072             change_done = TRUE;
11073             change_done_any = TRUE;
11074           }
11075         }
11076       }
11077     }
11078   }
11079
11080   RECURSION_LOOP_DETECTION_END();
11081
11082   return change_done_any;
11083 }
11084
11085 static boolean CheckElementChangeExt(int x, int y,
11086                                      int element,
11087                                      int trigger_element,
11088                                      int trigger_event,
11089                                      int trigger_player,
11090                                      int trigger_side)
11091 {
11092   boolean change_done = FALSE;
11093   int p;
11094
11095   if (!CAN_CHANGE_OR_HAS_ACTION(element) ||
11096       !HAS_ANY_CHANGE_EVENT(element, trigger_event))
11097     return FALSE;
11098
11099   if (Tile[x][y] == EL_BLOCKED)
11100   {
11101     Blocked2Moving(x, y, &x, &y);
11102     element = Tile[x][y];
11103   }
11104
11105   // check if element has already changed or is about to change after moving
11106   if ((game.engine_version < VERSION_IDENT(3,2,0,7) &&
11107        Tile[x][y] != element) ||
11108
11109       (game.engine_version >= VERSION_IDENT(3,2,0,7) &&
11110        (ChangeCount[x][y] >= game.max_num_changes_per_frame ||
11111         ChangePage[x][y] != -1)))
11112     return FALSE;
11113
11114   RECURSION_LOOP_DETECTION_START(trigger_element, FALSE);
11115
11116   for (p = 0; p < element_info[element].num_change_pages; p++)
11117   {
11118     struct ElementChangeInfo *change = &element_info[element].change_page[p];
11119
11120     /* check trigger element for all events where the element that is checked
11121        for changing interacts with a directly adjacent element -- this is
11122        different to element changes that affect other elements to change on the
11123        whole playfield (which is handeld by CheckTriggeredElementChangeExt()) */
11124     boolean check_trigger_element =
11125       (trigger_event == CE_NEXT_TO_X ||
11126        trigger_event == CE_TOUCHING_X ||
11127        trigger_event == CE_HITTING_X ||
11128        trigger_event == CE_HIT_BY_X ||
11129        trigger_event == CE_DIGGING_X); // this one was forgotten until 3.2.3
11130
11131     if (change->can_change_or_has_action &&
11132         change->has_event[trigger_event] &&
11133         change->trigger_side & trigger_side &&
11134         change->trigger_player & trigger_player &&
11135         (!check_trigger_element ||
11136          IS_EQUAL_OR_IN_GROUP(trigger_element, change->trigger_element)))
11137     {
11138       change->actual_trigger_element = trigger_element;
11139       change->actual_trigger_player = GET_PLAYER_FROM_BITS(trigger_player);
11140       change->actual_trigger_player_bits = trigger_player;
11141       change->actual_trigger_side = trigger_side;
11142       change->actual_trigger_ce_value = CustomValue[x][y];
11143       change->actual_trigger_ce_score = GET_CE_SCORE(trigger_element);
11144
11145       // special case: trigger element not at (x,y) position for some events
11146       if (check_trigger_element)
11147       {
11148         static struct
11149         {
11150           int dx, dy;
11151         } move_xy[] =
11152           {
11153             {  0,  0 },
11154             { -1,  0 },
11155             { +1,  0 },
11156             {  0,  0 },
11157             {  0, -1 },
11158             {  0,  0 }, { 0, 0 }, { 0, 0 },
11159             {  0, +1 }
11160           };
11161
11162         int xx = x + move_xy[MV_DIR_OPPOSITE(trigger_side)].dx;
11163         int yy = y + move_xy[MV_DIR_OPPOSITE(trigger_side)].dy;
11164
11165         change->actual_trigger_ce_value = CustomValue[xx][yy];
11166         change->actual_trigger_ce_score = GET_CE_SCORE(trigger_element);
11167       }
11168
11169       if (change->can_change && !change_done)
11170       {
11171         ChangeDelay[x][y] = 1;
11172         ChangeEvent[x][y] = trigger_event;
11173
11174         HandleElementChange(x, y, p);
11175
11176         change_done = TRUE;
11177       }
11178       else if (change->has_action)
11179       {
11180         ExecuteCustomElementAction(x, y, element, p);
11181         PlayLevelSoundElementAction(x, y, element, ACTION_PAGE_1 + p);
11182       }
11183     }
11184   }
11185
11186   RECURSION_LOOP_DETECTION_END();
11187
11188   return change_done;
11189 }
11190
11191 static void PlayPlayerSound(struct PlayerInfo *player)
11192 {
11193   int jx = player->jx, jy = player->jy;
11194   int sound_element = player->artwork_element;
11195   int last_action = player->last_action_waiting;
11196   int action = player->action_waiting;
11197
11198   if (player->is_waiting)
11199   {
11200     if (action != last_action)
11201       PlayLevelSoundElementAction(jx, jy, sound_element, action);
11202     else
11203       PlayLevelSoundElementActionIfLoop(jx, jy, sound_element, action);
11204   }
11205   else
11206   {
11207     if (action != last_action)
11208       StopSound(element_info[sound_element].sound[last_action]);
11209
11210     if (last_action == ACTION_SLEEPING)
11211       PlayLevelSoundElementAction(jx, jy, sound_element, ACTION_AWAKENING);
11212   }
11213 }
11214
11215 static void PlayAllPlayersSound(void)
11216 {
11217   int i;
11218
11219   for (i = 0; i < MAX_PLAYERS; i++)
11220     if (stored_player[i].active)
11221       PlayPlayerSound(&stored_player[i]);
11222 }
11223
11224 static void SetPlayerWaiting(struct PlayerInfo *player, boolean is_waiting)
11225 {
11226   boolean last_waiting = player->is_waiting;
11227   int move_dir = player->MovDir;
11228
11229   player->dir_waiting = move_dir;
11230   player->last_action_waiting = player->action_waiting;
11231
11232   if (is_waiting)
11233   {
11234     if (!last_waiting)          // not waiting -> waiting
11235     {
11236       player->is_waiting = TRUE;
11237
11238       player->frame_counter_bored =
11239         FrameCounter +
11240         game.player_boring_delay_fixed +
11241         GetSimpleRandom(game.player_boring_delay_random);
11242       player->frame_counter_sleeping =
11243         FrameCounter +
11244         game.player_sleeping_delay_fixed +
11245         GetSimpleRandom(game.player_sleeping_delay_random);
11246
11247       InitPlayerGfxAnimation(player, ACTION_WAITING, move_dir);
11248     }
11249
11250     if (game.player_sleeping_delay_fixed +
11251         game.player_sleeping_delay_random > 0 &&
11252         player->anim_delay_counter == 0 &&
11253         player->post_delay_counter == 0 &&
11254         FrameCounter >= player->frame_counter_sleeping)
11255       player->is_sleeping = TRUE;
11256     else if (game.player_boring_delay_fixed +
11257              game.player_boring_delay_random > 0 &&
11258              FrameCounter >= player->frame_counter_bored)
11259       player->is_bored = TRUE;
11260
11261     player->action_waiting = (player->is_sleeping ? ACTION_SLEEPING :
11262                               player->is_bored ? ACTION_BORING :
11263                               ACTION_WAITING);
11264
11265     if (player->is_sleeping && player->use_murphy)
11266     {
11267       // special case for sleeping Murphy when leaning against non-free tile
11268
11269       if (!IN_LEV_FIELD(player->jx - 1, player->jy) ||
11270           (Tile[player->jx - 1][player->jy] != EL_EMPTY &&
11271            !IS_MOVING(player->jx - 1, player->jy)))
11272         move_dir = MV_LEFT;
11273       else if (!IN_LEV_FIELD(player->jx + 1, player->jy) ||
11274                (Tile[player->jx + 1][player->jy] != EL_EMPTY &&
11275                 !IS_MOVING(player->jx + 1, player->jy)))
11276         move_dir = MV_RIGHT;
11277       else
11278         player->is_sleeping = FALSE;
11279
11280       player->dir_waiting = move_dir;
11281     }
11282
11283     if (player->is_sleeping)
11284     {
11285       if (player->num_special_action_sleeping > 0)
11286       {
11287         if (player->anim_delay_counter == 0 && player->post_delay_counter == 0)
11288         {
11289           int last_special_action = player->special_action_sleeping;
11290           int num_special_action = player->num_special_action_sleeping;
11291           int special_action =
11292             (last_special_action == ACTION_DEFAULT ? ACTION_SLEEPING_1 :
11293              last_special_action == ACTION_SLEEPING ? ACTION_SLEEPING :
11294              last_special_action < ACTION_SLEEPING_1 + num_special_action - 1 ?
11295              last_special_action + 1 : ACTION_SLEEPING);
11296           int special_graphic =
11297             el_act_dir2img(player->artwork_element, special_action, move_dir);
11298
11299           player->anim_delay_counter =
11300             graphic_info[special_graphic].anim_delay_fixed +
11301             GetSimpleRandom(graphic_info[special_graphic].anim_delay_random);
11302           player->post_delay_counter =
11303             graphic_info[special_graphic].post_delay_fixed +
11304             GetSimpleRandom(graphic_info[special_graphic].post_delay_random);
11305
11306           player->special_action_sleeping = special_action;
11307         }
11308
11309         if (player->anim_delay_counter > 0)
11310         {
11311           player->action_waiting = player->special_action_sleeping;
11312           player->anim_delay_counter--;
11313         }
11314         else if (player->post_delay_counter > 0)
11315         {
11316           player->post_delay_counter--;
11317         }
11318       }
11319     }
11320     else if (player->is_bored)
11321     {
11322       if (player->num_special_action_bored > 0)
11323       {
11324         if (player->anim_delay_counter == 0 && player->post_delay_counter == 0)
11325         {
11326           int special_action =
11327             ACTION_BORING_1 + GetSimpleRandom(player->num_special_action_bored);
11328           int special_graphic =
11329             el_act_dir2img(player->artwork_element, special_action, move_dir);
11330
11331           player->anim_delay_counter =
11332             graphic_info[special_graphic].anim_delay_fixed +
11333             GetSimpleRandom(graphic_info[special_graphic].anim_delay_random);
11334           player->post_delay_counter =
11335             graphic_info[special_graphic].post_delay_fixed +
11336             GetSimpleRandom(graphic_info[special_graphic].post_delay_random);
11337
11338           player->special_action_bored = special_action;
11339         }
11340
11341         if (player->anim_delay_counter > 0)
11342         {
11343           player->action_waiting = player->special_action_bored;
11344           player->anim_delay_counter--;
11345         }
11346         else if (player->post_delay_counter > 0)
11347         {
11348           player->post_delay_counter--;
11349         }
11350       }
11351     }
11352   }
11353   else if (last_waiting)        // waiting -> not waiting
11354   {
11355     player->is_waiting = FALSE;
11356     player->is_bored = FALSE;
11357     player->is_sleeping = FALSE;
11358
11359     player->frame_counter_bored = -1;
11360     player->frame_counter_sleeping = -1;
11361
11362     player->anim_delay_counter = 0;
11363     player->post_delay_counter = 0;
11364
11365     player->dir_waiting = player->MovDir;
11366     player->action_waiting = ACTION_DEFAULT;
11367
11368     player->special_action_bored = ACTION_DEFAULT;
11369     player->special_action_sleeping = ACTION_DEFAULT;
11370   }
11371 }
11372
11373 static void CheckSaveEngineSnapshot(struct PlayerInfo *player)
11374 {
11375   if ((!player->is_moving  && player->was_moving) ||
11376       (player->MovPos == 0 && player->was_moving) ||
11377       (player->is_snapping && !player->was_snapping) ||
11378       (player->is_dropping && !player->was_dropping))
11379   {
11380     if (!CheckSaveEngineSnapshotToList())
11381       return;
11382
11383     player->was_moving = FALSE;
11384     player->was_snapping = TRUE;
11385     player->was_dropping = TRUE;
11386   }
11387   else
11388   {
11389     if (player->is_moving)
11390       player->was_moving = TRUE;
11391
11392     if (!player->is_snapping)
11393       player->was_snapping = FALSE;
11394
11395     if (!player->is_dropping)
11396       player->was_dropping = FALSE;
11397   }
11398
11399   static struct MouseActionInfo mouse_action_last = { 0 };
11400   struct MouseActionInfo mouse_action = player->effective_mouse_action;
11401   boolean new_released = (!mouse_action.button && mouse_action_last.button);
11402
11403   if (new_released)
11404     CheckSaveEngineSnapshotToList();
11405
11406   mouse_action_last = mouse_action;
11407 }
11408
11409 static void CheckSingleStepMode(struct PlayerInfo *player)
11410 {
11411   if (tape.single_step && tape.recording && !tape.pausing)
11412   {
11413     // as it is called "single step mode", just return to pause mode when the
11414     // player stopped moving after one tile (or never starts moving at all)
11415     // (reverse logic needed here in case single step mode used in team mode)
11416     if (player->is_moving ||
11417         player->is_pushing ||
11418         player->is_dropping_pressed ||
11419         player->effective_mouse_action.button)
11420       game.enter_single_step_mode = FALSE;
11421   }
11422
11423   CheckSaveEngineSnapshot(player);
11424 }
11425
11426 static byte PlayerActions(struct PlayerInfo *player, byte player_action)
11427 {
11428   int left      = player_action & JOY_LEFT;
11429   int right     = player_action & JOY_RIGHT;
11430   int up        = player_action & JOY_UP;
11431   int down      = player_action & JOY_DOWN;
11432   int button1   = player_action & JOY_BUTTON_1;
11433   int button2   = player_action & JOY_BUTTON_2;
11434   int dx        = (left ? -1 : right ? 1 : 0);
11435   int dy        = (up   ? -1 : down  ? 1 : 0);
11436
11437   if (!player->active || tape.pausing)
11438     return 0;
11439
11440   if (player_action)
11441   {
11442     if (button1)
11443       SnapField(player, dx, dy);
11444     else
11445     {
11446       if (button2)
11447         DropElement(player);
11448
11449       MovePlayer(player, dx, dy);
11450     }
11451
11452     CheckSingleStepMode(player);
11453
11454     SetPlayerWaiting(player, FALSE);
11455
11456     return player_action;
11457   }
11458   else
11459   {
11460     // no actions for this player (no input at player's configured device)
11461
11462     DigField(player, 0, 0, 0, 0, 0, 0, DF_NO_PUSH);
11463     SnapField(player, 0, 0);
11464     CheckGravityMovementWhenNotMoving(player);
11465
11466     if (player->MovPos == 0)
11467       SetPlayerWaiting(player, TRUE);
11468
11469     if (player->MovPos == 0)    // needed for tape.playing
11470       player->is_moving = FALSE;
11471
11472     player->is_dropping = FALSE;
11473     player->is_dropping_pressed = FALSE;
11474     player->drop_pressed_delay = 0;
11475
11476     CheckSingleStepMode(player);
11477
11478     return 0;
11479   }
11480 }
11481
11482 static void SetMouseActionFromTapeAction(struct MouseActionInfo *mouse_action,
11483                                          byte *tape_action)
11484 {
11485   if (!tape.use_mouse_actions)
11486     return;
11487
11488   mouse_action->lx     = tape_action[TAPE_ACTION_LX];
11489   mouse_action->ly     = tape_action[TAPE_ACTION_LY];
11490   mouse_action->button = tape_action[TAPE_ACTION_BUTTON];
11491 }
11492
11493 static void SetTapeActionFromMouseAction(byte *tape_action,
11494                                          struct MouseActionInfo *mouse_action)
11495 {
11496   if (!tape.use_mouse_actions)
11497     return;
11498
11499   tape_action[TAPE_ACTION_LX]     = mouse_action->lx;
11500   tape_action[TAPE_ACTION_LY]     = mouse_action->ly;
11501   tape_action[TAPE_ACTION_BUTTON] = mouse_action->button;
11502 }
11503
11504 static void CheckLevelSolved(void)
11505 {
11506   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
11507   {
11508     if (game_em.level_solved &&
11509         !game_em.game_over)                             // game won
11510     {
11511       LevelSolved();
11512
11513       game_em.game_over = TRUE;
11514
11515       game.all_players_gone = TRUE;
11516     }
11517
11518     if (game_em.game_over)                              // game lost
11519       game.all_players_gone = TRUE;
11520   }
11521   else if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
11522   {
11523     if (game_sp.level_solved &&
11524         !game_sp.game_over)                             // game won
11525     {
11526       LevelSolved();
11527
11528       game_sp.game_over = TRUE;
11529
11530       game.all_players_gone = TRUE;
11531     }
11532
11533     if (game_sp.game_over)                              // game lost
11534       game.all_players_gone = TRUE;
11535   }
11536   else if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
11537   {
11538     if (game_mm.level_solved &&
11539         !game_mm.game_over)                             // game won
11540     {
11541       LevelSolved();
11542
11543       game_mm.game_over = TRUE;
11544
11545       game.all_players_gone = TRUE;
11546     }
11547
11548     if (game_mm.game_over)                              // game lost
11549       game.all_players_gone = TRUE;
11550   }
11551 }
11552
11553 static void CheckLevelTime_StepCounter(void)
11554 {
11555   int i;
11556
11557   TimePlayed++;
11558
11559   if (TimeLeft > 0)
11560   {
11561     TimeLeft--;
11562
11563     if (TimeLeft <= 10 && game.time_limit && !game.LevelSolved)
11564       PlaySound(SND_GAME_RUNNING_OUT_OF_TIME);
11565
11566     game_panel_controls[GAME_PANEL_TIME].value = TimeLeft;
11567
11568     DisplayGameControlValues();
11569
11570     if (!TimeLeft && game.time_limit && !game.LevelSolved)
11571       for (i = 0; i < MAX_PLAYERS; i++)
11572         KillPlayer(&stored_player[i]);
11573   }
11574   else if (game.no_level_time_limit && !game.all_players_gone)
11575   {
11576     game_panel_controls[GAME_PANEL_TIME].value = TimePlayed;
11577
11578     DisplayGameControlValues();
11579   }
11580 }
11581
11582 static void CheckLevelTime(void)
11583 {
11584   int i;
11585
11586   if (TimeFrames >= FRAMES_PER_SECOND)
11587   {
11588     TimeFrames = 0;
11589     TapeTime++;
11590
11591     for (i = 0; i < MAX_PLAYERS; i++)
11592     {
11593       struct PlayerInfo *player = &stored_player[i];
11594
11595       if (SHIELD_ON(player))
11596       {
11597         player->shield_normal_time_left--;
11598
11599         if (player->shield_deadly_time_left > 0)
11600           player->shield_deadly_time_left--;
11601       }
11602     }
11603
11604     if (!game.LevelSolved && !level.use_step_counter)
11605     {
11606       TimePlayed++;
11607
11608       if (TimeLeft > 0)
11609       {
11610         TimeLeft--;
11611
11612         if (TimeLeft <= 10 && game.time_limit)
11613           PlaySound(SND_GAME_RUNNING_OUT_OF_TIME);
11614
11615         /* this does not make sense: game_panel_controls[GAME_PANEL_TIME].value
11616            is reset from other values in UpdateGameDoorValues() -- FIX THIS */
11617
11618         game_panel_controls[GAME_PANEL_TIME].value = TimeLeft;
11619
11620         if (!TimeLeft && game.time_limit)
11621         {
11622           if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
11623             game_em.lev->killed_out_of_time = TRUE;
11624           else
11625             for (i = 0; i < MAX_PLAYERS; i++)
11626               KillPlayer(&stored_player[i]);
11627         }
11628       }
11629       else if (game.no_level_time_limit && !game.all_players_gone)
11630       {
11631         game_panel_controls[GAME_PANEL_TIME].value = TimePlayed;
11632       }
11633
11634       game_em.lev->time = (game.no_level_time_limit ? TimePlayed : TimeLeft);
11635     }
11636
11637     if (tape.recording || tape.playing)
11638       DrawVideoDisplay(VIDEO_STATE_TIME_ON, TapeTime);
11639   }
11640
11641   if (tape.recording || tape.playing)
11642     DrawVideoDisplay(VIDEO_STATE_FRAME_ON, FrameCounter);
11643
11644   UpdateAndDisplayGameControlValues();
11645 }
11646
11647 void AdvanceFrameAndPlayerCounters(int player_nr)
11648 {
11649   int i;
11650
11651   // advance frame counters (global frame counter and time frame counter)
11652   FrameCounter++;
11653   TimeFrames++;
11654
11655   // advance player counters (counters for move delay, move animation etc.)
11656   for (i = 0; i < MAX_PLAYERS; i++)
11657   {
11658     boolean advance_player_counters = (player_nr == -1 || player_nr == i);
11659     int move_delay_value = stored_player[i].move_delay_value;
11660     int move_frames = MOVE_DELAY_NORMAL_SPEED / move_delay_value;
11661
11662     if (!advance_player_counters)       // not all players may be affected
11663       continue;
11664
11665     if (move_frames == 0)       // less than one move per game frame
11666     {
11667       int stepsize = TILEX / move_delay_value;
11668       int delay = move_delay_value / MOVE_DELAY_NORMAL_SPEED;
11669       int count = (stored_player[i].is_moving ?
11670                    ABS(stored_player[i].MovPos) / stepsize : FrameCounter);
11671
11672       if (count % delay == 0)
11673         move_frames = 1;
11674     }
11675
11676     stored_player[i].Frame += move_frames;
11677
11678     if (stored_player[i].MovPos != 0)
11679       stored_player[i].StepFrame += move_frames;
11680
11681     if (stored_player[i].move_delay > 0)
11682       stored_player[i].move_delay--;
11683
11684     // due to bugs in previous versions, counter must count up, not down
11685     if (stored_player[i].push_delay != -1)
11686       stored_player[i].push_delay++;
11687
11688     if (stored_player[i].drop_delay > 0)
11689       stored_player[i].drop_delay--;
11690
11691     if (stored_player[i].is_dropping_pressed)
11692       stored_player[i].drop_pressed_delay++;
11693   }
11694 }
11695
11696 void AdvanceFrameCounter(void)
11697 {
11698   FrameCounter++;
11699 }
11700
11701 void AdvanceGfxFrame(void)
11702 {
11703   int x, y;
11704
11705   SCAN_PLAYFIELD(x, y)
11706   {
11707     GfxFrame[x][y]++;
11708   }
11709 }
11710
11711 void StartGameActions(boolean init_network_game, boolean record_tape,
11712                       int random_seed)
11713 {
11714   unsigned int new_random_seed = InitRND(random_seed);
11715
11716   if (record_tape)
11717     TapeStartRecording(new_random_seed);
11718
11719   if (setup.auto_pause_on_start && !tape.pausing)
11720     TapeTogglePause(TAPE_TOGGLE_MANUAL);
11721
11722   if (init_network_game)
11723   {
11724     SendToServer_LevelFile();
11725     SendToServer_StartPlaying();
11726
11727     return;
11728   }
11729
11730   InitGame();
11731 }
11732
11733 static void GameActionsExt(void)
11734 {
11735 #if 0
11736   static unsigned int game_frame_delay = 0;
11737 #endif
11738   unsigned int game_frame_delay_value;
11739   byte *recorded_player_action;
11740   byte summarized_player_action = 0;
11741   byte tape_action[MAX_TAPE_ACTIONS] = { 0 };
11742   int i;
11743
11744   // detect endless loops, caused by custom element programming
11745   if (recursion_loop_detected && recursion_loop_depth == 0)
11746   {
11747     char *message = getStringCat3("Internal Error! Element ",
11748                                   EL_NAME(recursion_loop_element),
11749                                   " caused endless loop! Quit the game?");
11750
11751     Warn("element '%s' caused endless loop in game engine",
11752          EL_NAME(recursion_loop_element));
11753
11754     RequestQuitGameExt(program.headless, level_editor_test_game, message);
11755
11756     recursion_loop_detected = FALSE;    // if game should be continued
11757
11758     free(message);
11759
11760     return;
11761   }
11762
11763   if (game.restart_level)
11764     StartGameActions(network.enabled, setup.autorecord, level.random_seed);
11765
11766   CheckLevelSolved();
11767
11768   if (game.LevelSolved && !game.LevelSolved_GameEnd)
11769     GameWon();
11770
11771   if (game.all_players_gone && !TAPE_IS_STOPPED(tape))
11772     TapeStop();
11773
11774   if (game_status != GAME_MODE_PLAYING)         // status might have changed
11775     return;
11776
11777   game_frame_delay_value =
11778     (tape.playing && tape.fast_forward ? FfwdFrameDelay : GameFrameDelay);
11779
11780   if (tape.playing && tape.warp_forward && !tape.pausing)
11781     game_frame_delay_value = 0;
11782
11783   SetVideoFrameDelay(game_frame_delay_value);
11784
11785   // (de)activate virtual buttons depending on current game status
11786   if (strEqual(setup.touch.control_type, TOUCH_CONTROL_VIRTUAL_BUTTONS))
11787   {
11788     if (game.all_players_gone)  // if no players there to be controlled anymore
11789       SetOverlayActive(FALSE);
11790     else if (!tape.playing)     // if game continues after tape stopped playing
11791       SetOverlayActive(TRUE);
11792   }
11793
11794 #if 0
11795 #if 0
11796   // ---------- main game synchronization point ----------
11797
11798   int skip = WaitUntilDelayReached(&game_frame_delay, game_frame_delay_value);
11799
11800   Debug("game:playing:skip", "skip == %d", skip);
11801
11802 #else
11803   // ---------- main game synchronization point ----------
11804
11805   WaitUntilDelayReached(&game_frame_delay, game_frame_delay_value);
11806 #endif
11807 #endif
11808
11809   if (network_playing && !network_player_action_received)
11810   {
11811     // try to get network player actions in time
11812
11813     // last chance to get network player actions without main loop delay
11814     HandleNetworking();
11815
11816     // game was quit by network peer
11817     if (game_status != GAME_MODE_PLAYING)
11818       return;
11819
11820     // check if network player actions still missing and game still running
11821     if (!network_player_action_received && !checkGameEnded())
11822       return;           // failed to get network player actions in time
11823
11824     // do not yet reset "network_player_action_received" (for tape.pausing)
11825   }
11826
11827   if (tape.pausing)
11828     return;
11829
11830   // at this point we know that we really continue executing the game
11831
11832   network_player_action_received = FALSE;
11833
11834   // when playing tape, read previously recorded player input from tape data
11835   recorded_player_action = (tape.playing ? TapePlayAction() : NULL);
11836
11837   local_player->effective_mouse_action = local_player->mouse_action;
11838
11839   if (recorded_player_action != NULL)
11840     SetMouseActionFromTapeAction(&local_player->effective_mouse_action,
11841                                  recorded_player_action);
11842
11843   // TapePlayAction() may return NULL when toggling to "pause before death"
11844   if (tape.pausing)
11845     return;
11846
11847   if (tape.set_centered_player)
11848   {
11849     game.centered_player_nr_next = tape.centered_player_nr_next;
11850     game.set_centered_player = TRUE;
11851   }
11852
11853   for (i = 0; i < MAX_PLAYERS; i++)
11854   {
11855     summarized_player_action |= stored_player[i].action;
11856
11857     if (!network_playing && (game.team_mode || tape.playing))
11858       stored_player[i].effective_action = stored_player[i].action;
11859   }
11860
11861   if (network_playing && !checkGameEnded())
11862     SendToServer_MovePlayer(summarized_player_action);
11863
11864   // summarize all actions at local players mapped input device position
11865   // (this allows using different input devices in single player mode)
11866   if (!network.enabled && !game.team_mode)
11867     stored_player[map_player_action[local_player->index_nr]].effective_action =
11868       summarized_player_action;
11869
11870   // summarize all actions at centered player in local team mode
11871   if (tape.recording &&
11872       setup.team_mode && !network.enabled &&
11873       setup.input_on_focus &&
11874       game.centered_player_nr != -1)
11875   {
11876     for (i = 0; i < MAX_PLAYERS; i++)
11877       stored_player[map_player_action[i]].effective_action =
11878         (i == game.centered_player_nr ? summarized_player_action : 0);
11879   }
11880
11881   if (recorded_player_action != NULL)
11882     for (i = 0; i < MAX_PLAYERS; i++)
11883       stored_player[i].effective_action = recorded_player_action[i];
11884
11885   for (i = 0; i < MAX_PLAYERS; i++)
11886   {
11887     tape_action[i] = stored_player[i].effective_action;
11888
11889     /* (this may happen in the RND game engine if a player was not present on
11890        the playfield on level start, but appeared later from a custom element */
11891     if (setup.team_mode &&
11892         tape.recording &&
11893         tape_action[i] &&
11894         !tape.player_participates[i])
11895       tape.player_participates[i] = TRUE;
11896   }
11897
11898   SetTapeActionFromMouseAction(tape_action,
11899                                &local_player->effective_mouse_action);
11900
11901   // only record actions from input devices, but not programmed actions
11902   if (tape.recording)
11903     TapeRecordAction(tape_action);
11904
11905   // remember if game was played (especially after tape stopped playing)
11906   if (!tape.playing && summarized_player_action && !checkGameFailed())
11907     game.GamePlayed = TRUE;
11908
11909 #if USE_NEW_PLAYER_ASSIGNMENTS
11910   // !!! also map player actions in single player mode !!!
11911   // if (game.team_mode)
11912   if (1)
11913   {
11914     byte mapped_action[MAX_PLAYERS];
11915
11916 #if DEBUG_PLAYER_ACTIONS
11917     for (i = 0; i < MAX_PLAYERS; i++)
11918       DebugContinued("", "%d, ", stored_player[i].effective_action);
11919 #endif
11920
11921     for (i = 0; i < MAX_PLAYERS; i++)
11922       mapped_action[i] = stored_player[map_player_action[i]].effective_action;
11923
11924     for (i = 0; i < MAX_PLAYERS; i++)
11925       stored_player[i].effective_action = mapped_action[i];
11926
11927 #if DEBUG_PLAYER_ACTIONS
11928     DebugContinued("", "=> ");
11929     for (i = 0; i < MAX_PLAYERS; i++)
11930       DebugContinued("", "%d, ", stored_player[i].effective_action);
11931     DebugContinued("game:playing:player", "\n");
11932 #endif
11933   }
11934 #if DEBUG_PLAYER_ACTIONS
11935   else
11936   {
11937     for (i = 0; i < MAX_PLAYERS; i++)
11938       DebugContinued("", "%d, ", stored_player[i].effective_action);
11939     DebugContinued("game:playing:player", "\n");
11940   }
11941 #endif
11942 #endif
11943
11944   for (i = 0; i < MAX_PLAYERS; i++)
11945   {
11946     // allow engine snapshot in case of changed movement attempt
11947     if ((game.snapshot.last_action[i] & KEY_MOTION) !=
11948         (stored_player[i].effective_action & KEY_MOTION))
11949       game.snapshot.changed_action = TRUE;
11950
11951     // allow engine snapshot in case of snapping/dropping attempt
11952     if ((game.snapshot.last_action[i] & KEY_BUTTON) == 0 &&
11953         (stored_player[i].effective_action & KEY_BUTTON) != 0)
11954       game.snapshot.changed_action = TRUE;
11955
11956     game.snapshot.last_action[i] = stored_player[i].effective_action;
11957   }
11958
11959   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
11960   {
11961     GameActions_EM_Main();
11962   }
11963   else if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
11964   {
11965     GameActions_SP_Main();
11966   }
11967   else if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
11968   {
11969     GameActions_MM_Main();
11970   }
11971   else
11972   {
11973     GameActions_RND_Main();
11974   }
11975
11976   BlitScreenToBitmap(backbuffer);
11977
11978   CheckLevelSolved();
11979   CheckLevelTime();
11980
11981   AdvanceFrameAndPlayerCounters(-1);    // advance counters for all players
11982
11983   if (global.show_frames_per_second)
11984   {
11985     static unsigned int fps_counter = 0;
11986     static int fps_frames = 0;
11987     unsigned int fps_delay_ms = Counter() - fps_counter;
11988
11989     fps_frames++;
11990
11991     if (fps_delay_ms >= 500)    // calculate FPS every 0.5 seconds
11992     {
11993       global.frames_per_second = 1000 * (float)fps_frames / fps_delay_ms;
11994
11995       fps_frames = 0;
11996       fps_counter = Counter();
11997
11998       // always draw FPS to screen after FPS value was updated
11999       redraw_mask |= REDRAW_FPS;
12000     }
12001
12002     // only draw FPS if no screen areas are deactivated (invisible warp mode)
12003     if (GetDrawDeactivationMask() == REDRAW_NONE)
12004       redraw_mask |= REDRAW_FPS;
12005   }
12006 }
12007
12008 static void GameActions_CheckSaveEngineSnapshot(void)
12009 {
12010   if (!game.snapshot.save_snapshot)
12011     return;
12012
12013   // clear flag for saving snapshot _before_ saving snapshot
12014   game.snapshot.save_snapshot = FALSE;
12015
12016   SaveEngineSnapshotToList();
12017 }
12018
12019 void GameActions(void)
12020 {
12021   GameActionsExt();
12022
12023   GameActions_CheckSaveEngineSnapshot();
12024 }
12025
12026 void GameActions_EM_Main(void)
12027 {
12028   byte effective_action[MAX_PLAYERS];
12029   int i;
12030
12031   for (i = 0; i < MAX_PLAYERS; i++)
12032     effective_action[i] = stored_player[i].effective_action;
12033
12034   GameActions_EM(effective_action);
12035 }
12036
12037 void GameActions_SP_Main(void)
12038 {
12039   byte effective_action[MAX_PLAYERS];
12040   int i;
12041
12042   for (i = 0; i < MAX_PLAYERS; i++)
12043     effective_action[i] = stored_player[i].effective_action;
12044
12045   GameActions_SP(effective_action);
12046
12047   for (i = 0; i < MAX_PLAYERS; i++)
12048   {
12049     if (stored_player[i].force_dropping)
12050       stored_player[i].action |= KEY_BUTTON_DROP;
12051
12052     stored_player[i].force_dropping = FALSE;
12053   }
12054 }
12055
12056 void GameActions_MM_Main(void)
12057 {
12058   AdvanceGfxFrame();
12059
12060   GameActions_MM(local_player->effective_mouse_action);
12061 }
12062
12063 void GameActions_RND_Main(void)
12064 {
12065   GameActions_RND();
12066 }
12067
12068 void GameActions_RND(void)
12069 {
12070   static struct MouseActionInfo mouse_action_last = { 0 };
12071   struct MouseActionInfo mouse_action = local_player->effective_mouse_action;
12072   int magic_wall_x = 0, magic_wall_y = 0;
12073   int i, x, y, element, graphic, last_gfx_frame;
12074
12075   InitPlayfieldScanModeVars();
12076
12077   if (game.engine_version >= VERSION_IDENT(3,2,0,7))
12078   {
12079     SCAN_PLAYFIELD(x, y)
12080     {
12081       ChangeCount[x][y] = 0;
12082       ChangeEvent[x][y] = -1;
12083     }
12084   }
12085
12086   if (game.set_centered_player)
12087   {
12088     boolean all_players_fit_to_screen = checkIfAllPlayersFitToScreen_RND();
12089
12090     // switching to "all players" only possible if all players fit to screen
12091     if (game.centered_player_nr_next == -1 && !all_players_fit_to_screen)
12092     {
12093       game.centered_player_nr_next = game.centered_player_nr;
12094       game.set_centered_player = FALSE;
12095     }
12096
12097     // do not switch focus to non-existing (or non-active) player
12098     if (game.centered_player_nr_next >= 0 &&
12099         !stored_player[game.centered_player_nr_next].active)
12100     {
12101       game.centered_player_nr_next = game.centered_player_nr;
12102       game.set_centered_player = FALSE;
12103     }
12104   }
12105
12106   if (game.set_centered_player &&
12107       ScreenMovPos == 0)        // screen currently aligned at tile position
12108   {
12109     int sx, sy;
12110
12111     if (game.centered_player_nr_next == -1)
12112     {
12113       setScreenCenteredToAllPlayers(&sx, &sy);
12114     }
12115     else
12116     {
12117       sx = stored_player[game.centered_player_nr_next].jx;
12118       sy = stored_player[game.centered_player_nr_next].jy;
12119     }
12120
12121     game.centered_player_nr = game.centered_player_nr_next;
12122     game.set_centered_player = FALSE;
12123
12124     DrawRelocateScreen(0, 0, sx, sy, TRUE, setup.quick_switch);
12125     DrawGameDoorValues();
12126   }
12127
12128   // check single step mode (set flag and clear again if any player is active)
12129   game.enter_single_step_mode =
12130     (tape.single_step && tape.recording && !tape.pausing);
12131
12132   for (i = 0; i < MAX_PLAYERS; i++)
12133   {
12134     int actual_player_action = stored_player[i].effective_action;
12135
12136 #if 1
12137     /* !!! THIS BREAKS THE FOLLOWING TAPES: !!!
12138        - rnd_equinox_tetrachloride 048
12139        - rnd_equinox_tetrachloride_ii 096
12140        - rnd_emanuel_schmieg 002
12141        - doctor_sloan_ww 001, 020
12142     */
12143     if (stored_player[i].MovPos == 0)
12144       CheckGravityMovement(&stored_player[i]);
12145 #endif
12146
12147     // overwrite programmed action with tape action
12148     if (stored_player[i].programmed_action)
12149       actual_player_action = stored_player[i].programmed_action;
12150
12151     PlayerActions(&stored_player[i], actual_player_action);
12152
12153     ScrollPlayer(&stored_player[i], SCROLL_GO_ON);
12154   }
12155
12156   // single step pause mode may already have been toggled by "ScrollPlayer()"
12157   if (game.enter_single_step_mode && !tape.pausing)
12158     TapeTogglePause(TAPE_TOGGLE_AUTOMATIC);
12159
12160   ScrollScreen(NULL, SCROLL_GO_ON);
12161
12162   /* for backwards compatibility, the following code emulates a fixed bug that
12163      occured when pushing elements (causing elements that just made their last
12164      pushing step to already (if possible) make their first falling step in the
12165      same game frame, which is bad); this code is also needed to use the famous
12166      "spring push bug" which is used in older levels and might be wanted to be
12167      used also in newer levels, but in this case the buggy pushing code is only
12168      affecting the "spring" element and no other elements */
12169
12170   if (game.engine_version < VERSION_IDENT(2,2,0,7) || level.use_spring_bug)
12171   {
12172     for (i = 0; i < MAX_PLAYERS; i++)
12173     {
12174       struct PlayerInfo *player = &stored_player[i];
12175       int x = player->jx;
12176       int y = player->jy;
12177
12178       if (player->active && player->is_pushing && player->is_moving &&
12179           IS_MOVING(x, y) &&
12180           (game.engine_version < VERSION_IDENT(2,2,0,7) ||
12181            Tile[x][y] == EL_SPRING))
12182       {
12183         ContinueMoving(x, y);
12184
12185         // continue moving after pushing (this is actually a bug)
12186         if (!IS_MOVING(x, y))
12187           Stop[x][y] = FALSE;
12188       }
12189     }
12190   }
12191
12192   SCAN_PLAYFIELD(x, y)
12193   {
12194     Last[x][y] = Tile[x][y];
12195
12196     ChangeCount[x][y] = 0;
12197     ChangeEvent[x][y] = -1;
12198
12199     // this must be handled before main playfield loop
12200     if (Tile[x][y] == EL_PLAYER_IS_LEAVING)
12201     {
12202       MovDelay[x][y]--;
12203       if (MovDelay[x][y] <= 0)
12204         RemoveField(x, y);
12205     }
12206
12207     if (Tile[x][y] == EL_ELEMENT_SNAPPING)
12208     {
12209       MovDelay[x][y]--;
12210       if (MovDelay[x][y] <= 0)
12211       {
12212         int element = Store[x][y];
12213         int move_direction = MovDir[x][y];
12214         int player_index_bit = Store2[x][y];
12215
12216         Store[x][y] = 0;
12217         Store2[x][y] = 0;
12218
12219         RemoveField(x, y);
12220         TEST_DrawLevelField(x, y);
12221
12222         TestFieldAfterSnapping(x, y, element, move_direction, player_index_bit);
12223
12224         if (IS_ENVELOPE(element))
12225           local_player->show_envelope = element;
12226       }
12227     }
12228
12229 #if DEBUG
12230     if (ChangePage[x][y] != -1 && ChangeDelay[x][y] != 1)
12231     {
12232       Debug("game:playing:GameActions_RND", "x = %d, y = %d: ChangePage != -1",
12233             x, y);
12234       Debug("game:playing:GameActions_RND", "This should never happen!");
12235
12236       ChangePage[x][y] = -1;
12237     }
12238 #endif
12239
12240     Stop[x][y] = FALSE;
12241     if (WasJustMoving[x][y] > 0)
12242       WasJustMoving[x][y]--;
12243     if (WasJustFalling[x][y] > 0)
12244       WasJustFalling[x][y]--;
12245     if (CheckCollision[x][y] > 0)
12246       CheckCollision[x][y]--;
12247     if (CheckImpact[x][y] > 0)
12248       CheckImpact[x][y]--;
12249
12250     GfxFrame[x][y]++;
12251
12252     /* reset finished pushing action (not done in ContinueMoving() to allow
12253        continuous pushing animation for elements with zero push delay) */
12254     if (GfxAction[x][y] == ACTION_PUSHING && !IS_MOVING(x, y))
12255     {
12256       ResetGfxAnimation(x, y);
12257       TEST_DrawLevelField(x, y);
12258     }
12259
12260 #if DEBUG
12261     if (IS_BLOCKED(x, y))
12262     {
12263       int oldx, oldy;
12264
12265       Blocked2Moving(x, y, &oldx, &oldy);
12266       if (!IS_MOVING(oldx, oldy))
12267       {
12268         Debug("game:playing:GameActions_RND", "(BLOCKED => MOVING) context corrupted!");
12269         Debug("game:playing:GameActions_RND", "BLOCKED: x = %d, y = %d", x, y);
12270         Debug("game:playing:GameActions_RND", "!MOVING: oldx = %d, oldy = %d", oldx, oldy);
12271         Debug("game:playing:GameActions_RND", "This should never happen!");
12272       }
12273     }
12274 #endif
12275   }
12276
12277   if (mouse_action.button)
12278   {
12279     int new_button = (mouse_action.button && mouse_action_last.button == 0);
12280     int ch_button = CH_SIDE_FROM_BUTTON(mouse_action.button);
12281
12282     x = mouse_action.lx;
12283     y = mouse_action.ly;
12284     element = Tile[x][y];
12285
12286     if (new_button)
12287     {
12288       CheckElementChangeByMouse(x, y, element, CE_CLICKED_BY_MOUSE, ch_button);
12289       CheckTriggeredElementChangeByMouse(x, y, element, CE_MOUSE_CLICKED_ON_X,
12290                                          ch_button);
12291     }
12292
12293     CheckElementChangeByMouse(x, y, element, CE_PRESSED_BY_MOUSE, ch_button);
12294     CheckTriggeredElementChangeByMouse(x, y, element, CE_MOUSE_PRESSED_ON_X,
12295                                        ch_button);
12296
12297     if (level.use_step_counter)
12298     {
12299       boolean counted_click = FALSE;
12300
12301       // element clicked that can change when clicked/pressed
12302       if (CAN_CHANGE_OR_HAS_ACTION(element) &&
12303           (HAS_ANY_CHANGE_EVENT(element, CE_CLICKED_BY_MOUSE) ||
12304            HAS_ANY_CHANGE_EVENT(element, CE_PRESSED_BY_MOUSE)))
12305         counted_click = TRUE;
12306
12307       // element clicked that can trigger change when clicked/pressed
12308       if (trigger_events[element][CE_MOUSE_CLICKED_ON_X] ||
12309           trigger_events[element][CE_MOUSE_PRESSED_ON_X])
12310         counted_click = TRUE;
12311
12312       if (new_button && counted_click)
12313         CheckLevelTime_StepCounter();
12314     }
12315   }
12316
12317   SCAN_PLAYFIELD(x, y)
12318   {
12319     element = Tile[x][y];
12320     graphic = el_act_dir2img(element, GfxAction[x][y], GfxDir[x][y]);
12321     last_gfx_frame = GfxFrame[x][y];
12322
12323     if (element == EL_EMPTY)
12324       graphic = el2img(GfxElementEmpty[x][y]);
12325
12326     ResetGfxFrame(x, y);
12327
12328     if (GfxFrame[x][y] != last_gfx_frame && !Stop[x][y])
12329       DrawLevelGraphicAnimation(x, y, graphic);
12330
12331     if (ANIM_MODE(graphic) == ANIM_RANDOM &&
12332         IS_NEXT_FRAME(GfxFrame[x][y], graphic))
12333       ResetRandomAnimationValue(x, y);
12334
12335     SetRandomAnimationValue(x, y);
12336
12337     PlayLevelSoundActionIfLoop(x, y, GfxAction[x][y]);
12338
12339     if (IS_INACTIVE(element))
12340     {
12341       if (IS_ANIMATED(graphic))
12342         DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
12343
12344       continue;
12345     }
12346
12347     // this may take place after moving, so 'element' may have changed
12348     if (IS_CHANGING(x, y) &&
12349         (game.engine_version < VERSION_IDENT(3,0,7,1) || !Stop[x][y]))
12350     {
12351       int page = element_info[element].event_page_nr[CE_DELAY];
12352
12353       HandleElementChange(x, y, page);
12354
12355       element = Tile[x][y];
12356       graphic = el_act_dir2img(element, GfxAction[x][y], GfxDir[x][y]);
12357     }
12358
12359     CheckNextToConditions(x, y);
12360
12361     if (!IS_MOVING(x, y) && (CAN_FALL(element) || CAN_MOVE(element)))
12362     {
12363       StartMoving(x, y);
12364
12365       element = Tile[x][y];
12366       graphic = el_act_dir2img(element, GfxAction[x][y], GfxDir[x][y]);
12367
12368       if (IS_ANIMATED(graphic) &&
12369           !IS_MOVING(x, y) &&
12370           !Stop[x][y])
12371         DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
12372
12373       if (IS_GEM(element) || element == EL_SP_INFOTRON)
12374         TEST_DrawTwinkleOnField(x, y);
12375     }
12376     else if (element == EL_ACID)
12377     {
12378       if (!Stop[x][y])
12379         DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
12380     }
12381     else if ((element == EL_EXIT_OPEN ||
12382               element == EL_EM_EXIT_OPEN ||
12383               element == EL_SP_EXIT_OPEN ||
12384               element == EL_STEEL_EXIT_OPEN ||
12385               element == EL_EM_STEEL_EXIT_OPEN ||
12386               element == EL_SP_TERMINAL ||
12387               element == EL_SP_TERMINAL_ACTIVE ||
12388               element == EL_EXTRA_TIME ||
12389               element == EL_SHIELD_NORMAL ||
12390               element == EL_SHIELD_DEADLY) &&
12391              IS_ANIMATED(graphic))
12392       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
12393     else if (IS_MOVING(x, y))
12394       ContinueMoving(x, y);
12395     else if (IS_ACTIVE_BOMB(element))
12396       CheckDynamite(x, y);
12397     else if (element == EL_AMOEBA_GROWING)
12398       AmoebaGrowing(x, y);
12399     else if (element == EL_AMOEBA_SHRINKING)
12400       AmoebaShrinking(x, y);
12401
12402 #if !USE_NEW_AMOEBA_CODE
12403     else if (IS_AMOEBALIVE(element))
12404       AmoebaReproduce(x, y);
12405 #endif
12406
12407     else if (element == EL_GAME_OF_LIFE || element == EL_BIOMAZE)
12408       Life(x, y);
12409     else if (element == EL_EXIT_CLOSED)
12410       CheckExit(x, y);
12411     else if (element == EL_EM_EXIT_CLOSED)
12412       CheckExitEM(x, y);
12413     else if (element == EL_STEEL_EXIT_CLOSED)
12414       CheckExitSteel(x, y);
12415     else if (element == EL_EM_STEEL_EXIT_CLOSED)
12416       CheckExitSteelEM(x, y);
12417     else if (element == EL_SP_EXIT_CLOSED)
12418       CheckExitSP(x, y);
12419     else if (element == EL_EXPANDABLE_WALL_GROWING ||
12420              element == EL_EXPANDABLE_STEELWALL_GROWING)
12421       WallGrowing(x, y);
12422     else if (element == EL_EXPANDABLE_WALL ||
12423              element == EL_EXPANDABLE_WALL_HORIZONTAL ||
12424              element == EL_EXPANDABLE_WALL_VERTICAL ||
12425              element == EL_EXPANDABLE_WALL_ANY ||
12426              element == EL_BD_EXPANDABLE_WALL ||
12427              element == EL_EXPANDABLE_STEELWALL_HORIZONTAL ||
12428              element == EL_EXPANDABLE_STEELWALL_VERTICAL ||
12429              element == EL_EXPANDABLE_STEELWALL_ANY)
12430       CheckWallGrowing(x, y);
12431     else if (element == EL_FLAMES)
12432       CheckForDragon(x, y);
12433     else if (element == EL_EXPLOSION)
12434       ; // drawing of correct explosion animation is handled separately
12435     else if (element == EL_ELEMENT_SNAPPING ||
12436              element == EL_DIAGONAL_SHRINKING ||
12437              element == EL_DIAGONAL_GROWING)
12438     {
12439       graphic = el_act_dir2img(GfxElement[x][y], GfxAction[x][y], GfxDir[x][y]);
12440
12441       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
12442     }
12443     else if (IS_ANIMATED(graphic) && !IS_CHANGING(x, y))
12444       DrawLevelGraphicAnimationIfNeeded(x, y, graphic);
12445
12446     if (IS_BELT_ACTIVE(element))
12447       PlayLevelSoundAction(x, y, ACTION_ACTIVE);
12448
12449     if (game.magic_wall_active)
12450     {
12451       int jx = local_player->jx, jy = local_player->jy;
12452
12453       // play the element sound at the position nearest to the player
12454       if ((element == EL_MAGIC_WALL_FULL ||
12455            element == EL_MAGIC_WALL_ACTIVE ||
12456            element == EL_MAGIC_WALL_EMPTYING ||
12457            element == EL_BD_MAGIC_WALL_FULL ||
12458            element == EL_BD_MAGIC_WALL_ACTIVE ||
12459            element == EL_BD_MAGIC_WALL_EMPTYING ||
12460            element == EL_DC_MAGIC_WALL_FULL ||
12461            element == EL_DC_MAGIC_WALL_ACTIVE ||
12462            element == EL_DC_MAGIC_WALL_EMPTYING) &&
12463           ABS(x - jx) + ABS(y - jy) <
12464           ABS(magic_wall_x - jx) + ABS(magic_wall_y - jy))
12465       {
12466         magic_wall_x = x;
12467         magic_wall_y = y;
12468       }
12469     }
12470   }
12471
12472 #if USE_NEW_AMOEBA_CODE
12473   // new experimental amoeba growth stuff
12474   if (!(FrameCounter % 8))
12475   {
12476     static unsigned int random = 1684108901;
12477
12478     for (i = 0; i < level.amoeba_speed * 28 / 8; i++)
12479     {
12480       x = RND(lev_fieldx);
12481       y = RND(lev_fieldy);
12482       element = Tile[x][y];
12483
12484       if (!IS_PLAYER(x, y) &&
12485           (element == EL_EMPTY ||
12486            CAN_GROW_INTO(element) ||
12487            element == EL_QUICKSAND_EMPTY ||
12488            element == EL_QUICKSAND_FAST_EMPTY ||
12489            element == EL_ACID_SPLASH_LEFT ||
12490            element == EL_ACID_SPLASH_RIGHT))
12491       {
12492         if ((IN_LEV_FIELD(x, y - 1) && Tile[x][y - 1] == EL_AMOEBA_WET) ||
12493             (IN_LEV_FIELD(x - 1, y) && Tile[x - 1][y] == EL_AMOEBA_WET) ||
12494             (IN_LEV_FIELD(x + 1, y) && Tile[x + 1][y] == EL_AMOEBA_WET) ||
12495             (IN_LEV_FIELD(x, y + 1) && Tile[x][y + 1] == EL_AMOEBA_WET))
12496           Tile[x][y] = EL_AMOEBA_DROP;
12497       }
12498
12499       random = random * 129 + 1;
12500     }
12501   }
12502 #endif
12503
12504   game.explosions_delayed = FALSE;
12505
12506   SCAN_PLAYFIELD(x, y)
12507   {
12508     element = Tile[x][y];
12509
12510     if (ExplodeField[x][y])
12511       Explode(x, y, EX_PHASE_START, ExplodeField[x][y]);
12512     else if (element == EL_EXPLOSION)
12513       Explode(x, y, ExplodePhase[x][y], EX_TYPE_NORMAL);
12514
12515     ExplodeField[x][y] = EX_TYPE_NONE;
12516   }
12517
12518   game.explosions_delayed = TRUE;
12519
12520   if (game.magic_wall_active)
12521   {
12522     if (!(game.magic_wall_time_left % 4))
12523     {
12524       int element = Tile[magic_wall_x][magic_wall_y];
12525
12526       if (element == EL_BD_MAGIC_WALL_FULL ||
12527           element == EL_BD_MAGIC_WALL_ACTIVE ||
12528           element == EL_BD_MAGIC_WALL_EMPTYING)
12529         PlayLevelSound(magic_wall_x, magic_wall_y, SND_BD_MAGIC_WALL_ACTIVE);
12530       else if (element == EL_DC_MAGIC_WALL_FULL ||
12531                element == EL_DC_MAGIC_WALL_ACTIVE ||
12532                element == EL_DC_MAGIC_WALL_EMPTYING)
12533         PlayLevelSound(magic_wall_x, magic_wall_y, SND_DC_MAGIC_WALL_ACTIVE);
12534       else
12535         PlayLevelSound(magic_wall_x, magic_wall_y, SND_MAGIC_WALL_ACTIVE);
12536     }
12537
12538     if (game.magic_wall_time_left > 0)
12539     {
12540       game.magic_wall_time_left--;
12541
12542       if (!game.magic_wall_time_left)
12543       {
12544         SCAN_PLAYFIELD(x, y)
12545         {
12546           element = Tile[x][y];
12547
12548           if (element == EL_MAGIC_WALL_ACTIVE ||
12549               element == EL_MAGIC_WALL_FULL)
12550           {
12551             Tile[x][y] = EL_MAGIC_WALL_DEAD;
12552             TEST_DrawLevelField(x, y);
12553           }
12554           else if (element == EL_BD_MAGIC_WALL_ACTIVE ||
12555                    element == EL_BD_MAGIC_WALL_FULL)
12556           {
12557             Tile[x][y] = EL_BD_MAGIC_WALL_DEAD;
12558             TEST_DrawLevelField(x, y);
12559           }
12560           else if (element == EL_DC_MAGIC_WALL_ACTIVE ||
12561                    element == EL_DC_MAGIC_WALL_FULL)
12562           {
12563             Tile[x][y] = EL_DC_MAGIC_WALL_DEAD;
12564             TEST_DrawLevelField(x, y);
12565           }
12566         }
12567
12568         game.magic_wall_active = FALSE;
12569       }
12570     }
12571   }
12572
12573   if (game.light_time_left > 0)
12574   {
12575     game.light_time_left--;
12576
12577     if (game.light_time_left == 0)
12578       RedrawAllLightSwitchesAndInvisibleElements();
12579   }
12580
12581   if (game.timegate_time_left > 0)
12582   {
12583     game.timegate_time_left--;
12584
12585     if (game.timegate_time_left == 0)
12586       CloseAllOpenTimegates();
12587   }
12588
12589   if (game.lenses_time_left > 0)
12590   {
12591     game.lenses_time_left--;
12592
12593     if (game.lenses_time_left == 0)
12594       RedrawAllInvisibleElementsForLenses();
12595   }
12596
12597   if (game.magnify_time_left > 0)
12598   {
12599     game.magnify_time_left--;
12600
12601     if (game.magnify_time_left == 0)
12602       RedrawAllInvisibleElementsForMagnifier();
12603   }
12604
12605   for (i = 0; i < MAX_PLAYERS; i++)
12606   {
12607     struct PlayerInfo *player = &stored_player[i];
12608
12609     if (SHIELD_ON(player))
12610     {
12611       if (player->shield_deadly_time_left)
12612         PlayLevelSound(player->jx, player->jy, SND_SHIELD_DEADLY_ACTIVE);
12613       else if (player->shield_normal_time_left)
12614         PlayLevelSound(player->jx, player->jy, SND_SHIELD_NORMAL_ACTIVE);
12615     }
12616   }
12617
12618 #if USE_DELAYED_GFX_REDRAW
12619   SCAN_PLAYFIELD(x, y)
12620   {
12621     if (GfxRedraw[x][y] != GFX_REDRAW_NONE)
12622     {
12623       /* !!! PROBLEM: THIS REDRAWS THE PLAYFIELD _AFTER_ THE SCAN, BUT TILES
12624          !!! MAY HAVE CHANGED AFTER BEING DRAWN DURING PLAYFIELD SCAN !!! */
12625
12626       if (GfxRedraw[x][y] & GFX_REDRAW_TILE)
12627         DrawLevelField(x, y);
12628
12629       if (GfxRedraw[x][y] & GFX_REDRAW_TILE_CRUMBLED)
12630         DrawLevelFieldCrumbled(x, y);
12631
12632       if (GfxRedraw[x][y] & GFX_REDRAW_TILE_CRUMBLED_NEIGHBOURS)
12633         DrawLevelFieldCrumbledNeighbours(x, y);
12634
12635       if (GfxRedraw[x][y] & GFX_REDRAW_TILE_TWINKLED)
12636         DrawTwinkleOnField(x, y);
12637     }
12638
12639     GfxRedraw[x][y] = GFX_REDRAW_NONE;
12640   }
12641 #endif
12642
12643   DrawAllPlayers();
12644   PlayAllPlayersSound();
12645
12646   for (i = 0; i < MAX_PLAYERS; i++)
12647   {
12648     struct PlayerInfo *player = &stored_player[i];
12649
12650     if (player->show_envelope != 0 && (!player->active ||
12651                                        player->MovPos == 0))
12652     {
12653       ShowEnvelope(player->show_envelope - EL_ENVELOPE_1);
12654
12655       player->show_envelope = 0;
12656     }
12657   }
12658
12659   // use random number generator in every frame to make it less predictable
12660   if (game.engine_version >= VERSION_IDENT(3,1,1,0))
12661     RND(1);
12662
12663   mouse_action_last = mouse_action;
12664 }
12665
12666 static boolean AllPlayersInSight(struct PlayerInfo *player, int x, int y)
12667 {
12668   int min_x = x, min_y = y, max_x = x, max_y = y;
12669   int scr_fieldx = getScreenFieldSizeX();
12670   int scr_fieldy = getScreenFieldSizeY();
12671   int i;
12672
12673   for (i = 0; i < MAX_PLAYERS; i++)
12674   {
12675     int jx = stored_player[i].jx, jy = stored_player[i].jy;
12676
12677     if (!stored_player[i].active || &stored_player[i] == player)
12678       continue;
12679
12680     min_x = MIN(min_x, jx);
12681     min_y = MIN(min_y, jy);
12682     max_x = MAX(max_x, jx);
12683     max_y = MAX(max_y, jy);
12684   }
12685
12686   return (max_x - min_x < scr_fieldx && max_y - min_y < scr_fieldy);
12687 }
12688
12689 static boolean AllPlayersInVisibleScreen(void)
12690 {
12691   int i;
12692
12693   for (i = 0; i < MAX_PLAYERS; i++)
12694   {
12695     int jx = stored_player[i].jx, jy = stored_player[i].jy;
12696
12697     if (!stored_player[i].active)
12698       continue;
12699
12700     if (!IN_VIS_FIELD(SCREENX(jx), SCREENY(jy)))
12701       return FALSE;
12702   }
12703
12704   return TRUE;
12705 }
12706
12707 void ScrollLevel(int dx, int dy)
12708 {
12709   int scroll_offset = 2 * TILEX_VAR;
12710   int x, y;
12711
12712   BlitBitmap(drawto_field, drawto_field,
12713              FX + TILEX_VAR * (dx == -1) - scroll_offset,
12714              FY + TILEY_VAR * (dy == -1) - scroll_offset,
12715              SXSIZE - TILEX_VAR * (dx != 0) + 2 * scroll_offset,
12716              SYSIZE - TILEY_VAR * (dy != 0) + 2 * scroll_offset,
12717              FX + TILEX_VAR * (dx == 1) - scroll_offset,
12718              FY + TILEY_VAR * (dy == 1) - scroll_offset);
12719
12720   if (dx != 0)
12721   {
12722     x = (dx == 1 ? BX1 : BX2);
12723     for (y = BY1; y <= BY2; y++)
12724       DrawScreenField(x, y);
12725   }
12726
12727   if (dy != 0)
12728   {
12729     y = (dy == 1 ? BY1 : BY2);
12730     for (x = BX1; x <= BX2; x++)
12731       DrawScreenField(x, y);
12732   }
12733
12734   redraw_mask |= REDRAW_FIELD;
12735 }
12736
12737 static boolean canFallDown(struct PlayerInfo *player)
12738 {
12739   int jx = player->jx, jy = player->jy;
12740
12741   return (IN_LEV_FIELD(jx, jy + 1) &&
12742           (IS_FREE(jx, jy + 1) ||
12743            (Tile[jx][jy + 1] == EL_ACID && player->can_fall_into_acid)) &&
12744           IS_WALKABLE_FROM(Tile[jx][jy], MV_DOWN) &&
12745           !IS_WALKABLE_INSIDE(Tile[jx][jy]));
12746 }
12747
12748 static boolean canPassField(int x, int y, int move_dir)
12749 {
12750   int opposite_dir = MV_DIR_OPPOSITE(move_dir);
12751   int dx = (move_dir & MV_LEFT ? -1 : move_dir & MV_RIGHT ? +1 : 0);
12752   int dy = (move_dir & MV_UP   ? -1 : move_dir & MV_DOWN  ? +1 : 0);
12753   int nextx = x + dx;
12754   int nexty = y + dy;
12755   int element = Tile[x][y];
12756
12757   return (IS_PASSABLE_FROM(element, opposite_dir) &&
12758           !CAN_MOVE(element) &&
12759           IN_LEV_FIELD(nextx, nexty) && !IS_PLAYER(nextx, nexty) &&
12760           IS_WALKABLE_FROM(Tile[nextx][nexty], move_dir) &&
12761           (level.can_pass_to_walkable || IS_FREE(nextx, nexty)));
12762 }
12763
12764 static boolean canMoveToValidFieldWithGravity(int x, int y, int move_dir)
12765 {
12766   int opposite_dir = MV_DIR_OPPOSITE(move_dir);
12767   int dx = (move_dir & MV_LEFT ? -1 : move_dir & MV_RIGHT ? +1 : 0);
12768   int dy = (move_dir & MV_UP   ? -1 : move_dir & MV_DOWN  ? +1 : 0);
12769   int newx = x + dx;
12770   int newy = y + dy;
12771
12772   return (IN_LEV_FIELD(newx, newy) && !IS_FREE_OR_PLAYER(newx, newy) &&
12773           IS_GRAVITY_REACHABLE(Tile[newx][newy]) &&
12774           (IS_DIGGABLE(Tile[newx][newy]) ||
12775            IS_WALKABLE_FROM(Tile[newx][newy], opposite_dir) ||
12776            canPassField(newx, newy, move_dir)));
12777 }
12778
12779 static void CheckGravityMovement(struct PlayerInfo *player)
12780 {
12781   if (player->gravity && !player->programmed_action)
12782   {
12783     int move_dir_horizontal = player->effective_action & MV_HORIZONTAL;
12784     int move_dir_vertical   = player->effective_action & MV_VERTICAL;
12785     boolean player_is_snapping = (player->effective_action & JOY_BUTTON_1);
12786     int jx = player->jx, jy = player->jy;
12787     boolean player_is_moving_to_valid_field =
12788       (!player_is_snapping &&
12789        (canMoveToValidFieldWithGravity(jx, jy, move_dir_horizontal) ||
12790         canMoveToValidFieldWithGravity(jx, jy, move_dir_vertical)));
12791     boolean player_can_fall_down = canFallDown(player);
12792
12793     if (player_can_fall_down &&
12794         !player_is_moving_to_valid_field)
12795       player->programmed_action = MV_DOWN;
12796   }
12797 }
12798
12799 static void CheckGravityMovementWhenNotMoving(struct PlayerInfo *player)
12800 {
12801   return CheckGravityMovement(player);
12802
12803   if (player->gravity && !player->programmed_action)
12804   {
12805     int jx = player->jx, jy = player->jy;
12806     boolean field_under_player_is_free =
12807       (IN_LEV_FIELD(jx, jy + 1) && IS_FREE(jx, jy + 1));
12808     boolean player_is_standing_on_valid_field =
12809       (IS_WALKABLE_INSIDE(Tile[jx][jy]) ||
12810        (IS_WALKABLE(Tile[jx][jy]) &&
12811         !(element_info[Tile[jx][jy]].access_direction & MV_DOWN)));
12812
12813     if (field_under_player_is_free && !player_is_standing_on_valid_field)
12814       player->programmed_action = MV_DOWN;
12815   }
12816 }
12817
12818 /*
12819   MovePlayerOneStep()
12820   -----------------------------------------------------------------------------
12821   dx, dy:               direction (non-diagonal) to try to move the player to
12822   real_dx, real_dy:     direction as read from input device (can be diagonal)
12823 */
12824
12825 boolean MovePlayerOneStep(struct PlayerInfo *player,
12826                           int dx, int dy, int real_dx, int real_dy)
12827 {
12828   int jx = player->jx, jy = player->jy;
12829   int new_jx = jx + dx, new_jy = jy + dy;
12830   int can_move;
12831   boolean player_can_move = !player->cannot_move;
12832
12833   if (!player->active || (!dx && !dy))
12834     return MP_NO_ACTION;
12835
12836   player->MovDir = (dx < 0 ? MV_LEFT :
12837                     dx > 0 ? MV_RIGHT :
12838                     dy < 0 ? MV_UP :
12839                     dy > 0 ? MV_DOWN :  MV_NONE);
12840
12841   if (!IN_LEV_FIELD(new_jx, new_jy))
12842     return MP_NO_ACTION;
12843
12844   if (!player_can_move)
12845   {
12846     if (player->MovPos == 0)
12847     {
12848       player->is_moving = FALSE;
12849       player->is_digging = FALSE;
12850       player->is_collecting = FALSE;
12851       player->is_snapping = FALSE;
12852       player->is_pushing = FALSE;
12853     }
12854   }
12855
12856   if (!network.enabled && game.centered_player_nr == -1 &&
12857       !AllPlayersInSight(player, new_jx, new_jy))
12858     return MP_NO_ACTION;
12859
12860   can_move = DigField(player, jx, jy, new_jx, new_jy, real_dx, real_dy, DF_DIG);
12861   if (can_move != MP_MOVING)
12862     return can_move;
12863
12864   // check if DigField() has caused relocation of the player
12865   if (player->jx != jx || player->jy != jy)
12866     return MP_NO_ACTION;        // <-- !!! CHECK THIS [-> MP_ACTION ?] !!!
12867
12868   StorePlayer[jx][jy] = 0;
12869   player->last_jx = jx;
12870   player->last_jy = jy;
12871   player->jx = new_jx;
12872   player->jy = new_jy;
12873   StorePlayer[new_jx][new_jy] = player->element_nr;
12874
12875   if (player->move_delay_value_next != -1)
12876   {
12877     player->move_delay_value = player->move_delay_value_next;
12878     player->move_delay_value_next = -1;
12879   }
12880
12881   player->MovPos =
12882     (dx > 0 || dy > 0 ? -1 : 1) * (TILEX - TILEX / player->move_delay_value);
12883
12884   player->step_counter++;
12885
12886   PlayerVisit[jx][jy] = FrameCounter;
12887
12888   player->is_moving = TRUE;
12889
12890 #if 1
12891   // should better be called in MovePlayer(), but this breaks some tapes
12892   ScrollPlayer(player, SCROLL_INIT);
12893 #endif
12894
12895   return MP_MOVING;
12896 }
12897
12898 boolean MovePlayer(struct PlayerInfo *player, int dx, int dy)
12899 {
12900   int jx = player->jx, jy = player->jy;
12901   int old_jx = jx, old_jy = jy;
12902   int moved = MP_NO_ACTION;
12903
12904   if (!player->active)
12905     return FALSE;
12906
12907   if (!dx && !dy)
12908   {
12909     if (player->MovPos == 0)
12910     {
12911       player->is_moving = FALSE;
12912       player->is_digging = FALSE;
12913       player->is_collecting = FALSE;
12914       player->is_snapping = FALSE;
12915       player->is_pushing = FALSE;
12916     }
12917
12918     return FALSE;
12919   }
12920
12921   if (player->move_delay > 0)
12922     return FALSE;
12923
12924   player->move_delay = -1;              // set to "uninitialized" value
12925
12926   // store if player is automatically moved to next field
12927   player->is_auto_moving = (player->programmed_action != MV_NONE);
12928
12929   // remove the last programmed player action
12930   player->programmed_action = 0;
12931
12932   if (player->MovPos)
12933   {
12934     // should only happen if pre-1.2 tape recordings are played
12935     // this is only for backward compatibility
12936
12937     int original_move_delay_value = player->move_delay_value;
12938
12939 #if DEBUG
12940     Debug("game:playing:MovePlayer",
12941           "THIS SHOULD ONLY HAPPEN WITH PRE-1.2 LEVEL TAPES. [%d]",
12942           tape.counter);
12943 #endif
12944
12945     // scroll remaining steps with finest movement resolution
12946     player->move_delay_value = MOVE_DELAY_NORMAL_SPEED;
12947
12948     while (player->MovPos)
12949     {
12950       ScrollPlayer(player, SCROLL_GO_ON);
12951       ScrollScreen(NULL, SCROLL_GO_ON);
12952
12953       AdvanceFrameAndPlayerCounters(player->index_nr);
12954
12955       DrawAllPlayers();
12956       BackToFront_WithFrameDelay(0);
12957     }
12958
12959     player->move_delay_value = original_move_delay_value;
12960   }
12961
12962   player->is_active = FALSE;
12963
12964   if (player->last_move_dir & MV_HORIZONTAL)
12965   {
12966     if (!(moved |= MovePlayerOneStep(player, 0, dy, dx, dy)))
12967       moved |= MovePlayerOneStep(player, dx, 0, dx, dy);
12968   }
12969   else
12970   {
12971     if (!(moved |= MovePlayerOneStep(player, dx, 0, dx, dy)))
12972       moved |= MovePlayerOneStep(player, 0, dy, dx, dy);
12973   }
12974
12975   if (!moved && !player->is_active)
12976   {
12977     player->is_moving = FALSE;
12978     player->is_digging = FALSE;
12979     player->is_collecting = FALSE;
12980     player->is_snapping = FALSE;
12981     player->is_pushing = FALSE;
12982   }
12983
12984   jx = player->jx;
12985   jy = player->jy;
12986
12987   if (moved & MP_MOVING && !ScreenMovPos &&
12988       (player->index_nr == game.centered_player_nr ||
12989        game.centered_player_nr == -1))
12990   {
12991     int old_scroll_x = scroll_x, old_scroll_y = scroll_y;
12992
12993     if (!IN_VIS_FIELD(SCREENX(jx), SCREENY(jy)))
12994     {
12995       // actual player has left the screen -- scroll in that direction
12996       if (jx != old_jx)         // player has moved horizontally
12997         scroll_x += (jx - old_jx);
12998       else                      // player has moved vertically
12999         scroll_y += (jy - old_jy);
13000     }
13001     else
13002     {
13003       int offset_raw = game.scroll_delay_value;
13004
13005       if (jx != old_jx)         // player has moved horizontally
13006       {
13007         int offset = MIN(offset_raw, (SCR_FIELDX - 2) / 2);
13008         int offset_x = offset * (player->MovDir == MV_LEFT ? +1 : -1);
13009         int new_scroll_x = jx - MIDPOSX + offset_x;
13010
13011         if ((player->MovDir == MV_LEFT  && scroll_x > new_scroll_x) ||
13012             (player->MovDir == MV_RIGHT && scroll_x < new_scroll_x))
13013           scroll_x = new_scroll_x;
13014
13015         // don't scroll over playfield boundaries
13016         scroll_x = MIN(MAX(SBX_Left, scroll_x), SBX_Right);
13017
13018         // don't scroll more than one field at a time
13019         scroll_x = old_scroll_x + SIGN(scroll_x - old_scroll_x);
13020
13021         // don't scroll against the player's moving direction
13022         if ((player->MovDir == MV_LEFT  && scroll_x > old_scroll_x) ||
13023             (player->MovDir == MV_RIGHT && scroll_x < old_scroll_x))
13024           scroll_x = old_scroll_x;
13025       }
13026       else                      // player has moved vertically
13027       {
13028         int offset = MIN(offset_raw, (SCR_FIELDY - 2) / 2);
13029         int offset_y = offset * (player->MovDir == MV_UP ? +1 : -1);
13030         int new_scroll_y = jy - MIDPOSY + offset_y;
13031
13032         if ((player->MovDir == MV_UP   && scroll_y > new_scroll_y) ||
13033             (player->MovDir == MV_DOWN && scroll_y < new_scroll_y))
13034           scroll_y = new_scroll_y;
13035
13036         // don't scroll over playfield boundaries
13037         scroll_y = MIN(MAX(SBY_Upper, scroll_y), SBY_Lower);
13038
13039         // don't scroll more than one field at a time
13040         scroll_y = old_scroll_y + SIGN(scroll_y - old_scroll_y);
13041
13042         // don't scroll against the player's moving direction
13043         if ((player->MovDir == MV_UP   && scroll_y > old_scroll_y) ||
13044             (player->MovDir == MV_DOWN && scroll_y < old_scroll_y))
13045           scroll_y = old_scroll_y;
13046       }
13047     }
13048
13049     if (scroll_x != old_scroll_x || scroll_y != old_scroll_y)
13050     {
13051       if (!network.enabled && game.centered_player_nr == -1 &&
13052           !AllPlayersInVisibleScreen())
13053       {
13054         scroll_x = old_scroll_x;
13055         scroll_y = old_scroll_y;
13056       }
13057       else
13058       {
13059         ScrollScreen(player, SCROLL_INIT);
13060         ScrollLevel(old_scroll_x - scroll_x, old_scroll_y - scroll_y);
13061       }
13062     }
13063   }
13064
13065   player->StepFrame = 0;
13066
13067   if (moved & MP_MOVING)
13068   {
13069     if (old_jx != jx && old_jy == jy)
13070       player->MovDir = (old_jx < jx ? MV_RIGHT : MV_LEFT);
13071     else if (old_jx == jx && old_jy != jy)
13072       player->MovDir = (old_jy < jy ? MV_DOWN : MV_UP);
13073
13074     TEST_DrawLevelField(jx, jy);        // for "crumbled sand"
13075
13076     player->last_move_dir = player->MovDir;
13077     player->is_moving = TRUE;
13078     player->is_snapping = FALSE;
13079     player->is_switching = FALSE;
13080     player->is_dropping = FALSE;
13081     player->is_dropping_pressed = FALSE;
13082     player->drop_pressed_delay = 0;
13083
13084 #if 0
13085     // should better be called here than above, but this breaks some tapes
13086     ScrollPlayer(player, SCROLL_INIT);
13087 #endif
13088   }
13089   else
13090   {
13091     CheckGravityMovementWhenNotMoving(player);
13092
13093     player->is_moving = FALSE;
13094
13095     /* at this point, the player is allowed to move, but cannot move right now
13096        (e.g. because of something blocking the way) -- ensure that the player
13097        is also allowed to move in the next frame (in old versions before 3.1.1,
13098        the player was forced to wait again for eight frames before next try) */
13099
13100     if (game.engine_version >= VERSION_IDENT(3,1,1,0))
13101       player->move_delay = 0;   // allow direct movement in the next frame
13102   }
13103
13104   if (player->move_delay == -1)         // not yet initialized by DigField()
13105     player->move_delay = player->move_delay_value;
13106
13107   if (game.engine_version < VERSION_IDENT(3,0,7,0))
13108   {
13109     TestIfPlayerTouchesBadThing(jx, jy);
13110     TestIfPlayerTouchesCustomElement(jx, jy);
13111   }
13112
13113   if (!player->active)
13114     RemovePlayer(player);
13115
13116   return moved;
13117 }
13118
13119 void ScrollPlayer(struct PlayerInfo *player, int mode)
13120 {
13121   int jx = player->jx, jy = player->jy;
13122   int last_jx = player->last_jx, last_jy = player->last_jy;
13123   int move_stepsize = TILEX / player->move_delay_value;
13124
13125   if (!player->active)
13126     return;
13127
13128   if (player->MovPos == 0 && mode == SCROLL_GO_ON)      // player not moving
13129     return;
13130
13131   if (mode == SCROLL_INIT)
13132   {
13133     player->actual_frame_counter.count = FrameCounter;
13134     player->GfxPos = move_stepsize * (player->MovPos / move_stepsize);
13135
13136     if ((player->block_last_field || player->block_delay_adjustment > 0) &&
13137         Tile[last_jx][last_jy] == EL_EMPTY)
13138     {
13139       int last_field_block_delay = 0;   // start with no blocking at all
13140       int block_delay_adjustment = player->block_delay_adjustment;
13141
13142       // if player blocks last field, add delay for exactly one move
13143       if (player->block_last_field)
13144       {
13145         last_field_block_delay += player->move_delay_value;
13146
13147         // when blocking enabled, prevent moving up despite gravity
13148         if (player->gravity && player->MovDir == MV_UP)
13149           block_delay_adjustment = -1;
13150       }
13151
13152       // add block delay adjustment (also possible when not blocking)
13153       last_field_block_delay += block_delay_adjustment;
13154
13155       Tile[last_jx][last_jy] = EL_PLAYER_IS_LEAVING;
13156       MovDelay[last_jx][last_jy] = last_field_block_delay + 1;
13157     }
13158
13159     if (player->MovPos != 0)    // player has not yet reached destination
13160       return;
13161   }
13162   else if (!FrameReached(&player->actual_frame_counter))
13163     return;
13164
13165   if (player->MovPos != 0)
13166   {
13167     player->MovPos += (player->MovPos > 0 ? -1 : 1) * move_stepsize;
13168     player->GfxPos = move_stepsize * (player->MovPos / move_stepsize);
13169
13170     // before DrawPlayer() to draw correct player graphic for this case
13171     if (player->MovPos == 0)
13172       CheckGravityMovement(player);
13173   }
13174
13175   if (player->MovPos == 0)      // player reached destination field
13176   {
13177     if (player->move_delay_reset_counter > 0)
13178     {
13179       player->move_delay_reset_counter--;
13180
13181       if (player->move_delay_reset_counter == 0)
13182       {
13183         // continue with normal speed after quickly moving through gate
13184         HALVE_PLAYER_SPEED(player);
13185
13186         // be able to make the next move without delay
13187         player->move_delay = 0;
13188       }
13189     }
13190
13191     if (Tile[jx][jy] == EL_EXIT_OPEN ||
13192         Tile[jx][jy] == EL_EM_EXIT_OPEN ||
13193         Tile[jx][jy] == EL_EM_EXIT_OPENING ||
13194         Tile[jx][jy] == EL_STEEL_EXIT_OPEN ||
13195         Tile[jx][jy] == EL_EM_STEEL_EXIT_OPEN ||
13196         Tile[jx][jy] == EL_EM_STEEL_EXIT_OPENING ||
13197         Tile[jx][jy] == EL_SP_EXIT_OPEN ||
13198         Tile[jx][jy] == EL_SP_EXIT_OPENING)     // <-- special case
13199     {
13200       ExitPlayer(player);
13201
13202       if (game.players_still_needed == 0 &&
13203           (game.friends_still_needed == 0 ||
13204            IS_SP_ELEMENT(Tile[jx][jy])))
13205         LevelSolved();
13206     }
13207
13208     player->last_jx = jx;
13209     player->last_jy = jy;
13210
13211     // this breaks one level: "machine", level 000
13212     {
13213       int move_direction = player->MovDir;
13214       int enter_side = MV_DIR_OPPOSITE(move_direction);
13215       int leave_side = move_direction;
13216       int old_jx = last_jx;
13217       int old_jy = last_jy;
13218       int old_element = Tile[old_jx][old_jy];
13219       int new_element = Tile[jx][jy];
13220
13221       if (IS_CUSTOM_ELEMENT(old_element))
13222         CheckElementChangeByPlayer(old_jx, old_jy, old_element,
13223                                    CE_LEFT_BY_PLAYER,
13224                                    player->index_bit, leave_side);
13225
13226       CheckTriggeredElementChangeByPlayer(old_jx, old_jy, old_element,
13227                                           CE_PLAYER_LEAVES_X,
13228                                           player->index_bit, leave_side);
13229
13230       // needed because pushed element has not yet reached its destination,
13231       // so it would trigger a change event at its previous field location
13232       if (!player->is_pushing)
13233       {
13234         if (IS_CUSTOM_ELEMENT(new_element))
13235           CheckElementChangeByPlayer(jx, jy, new_element, CE_ENTERED_BY_PLAYER,
13236                                      player->index_bit, enter_side);
13237
13238         CheckTriggeredElementChangeByPlayer(jx, jy, new_element,
13239                                             CE_PLAYER_ENTERS_X,
13240                                             player->index_bit, enter_side);
13241       }
13242
13243       CheckTriggeredElementChangeBySide(jx, jy, player->initial_element,
13244                                         CE_MOVE_OF_X, move_direction);
13245     }
13246
13247     if (game.engine_version >= VERSION_IDENT(3,0,7,0))
13248     {
13249       TestIfPlayerTouchesBadThing(jx, jy);
13250       TestIfPlayerTouchesCustomElement(jx, jy);
13251
13252       // needed because pushed element has not yet reached its destination,
13253       // so it would trigger a change event at its previous field location
13254       if (!player->is_pushing)
13255         TestIfElementTouchesCustomElement(jx, jy);      // for empty space
13256
13257       if (level.finish_dig_collect &&
13258           (player->is_digging || player->is_collecting))
13259       {
13260         int last_element = player->last_removed_element;
13261         int move_direction = player->MovDir;
13262         int enter_side = MV_DIR_OPPOSITE(move_direction);
13263         int change_event = (player->is_digging ? CE_PLAYER_DIGS_X :
13264                             CE_PLAYER_COLLECTS_X);
13265
13266         CheckTriggeredElementChangeByPlayer(jx, jy, last_element, change_event,
13267                                             player->index_bit, enter_side);
13268
13269         player->last_removed_element = EL_UNDEFINED;
13270       }
13271
13272       if (!player->active)
13273         RemovePlayer(player);
13274     }
13275
13276     if (level.use_step_counter)
13277       CheckLevelTime_StepCounter();
13278
13279     if (tape.single_step && tape.recording && !tape.pausing &&
13280         !player->programmed_action)
13281       TapeTogglePause(TAPE_TOGGLE_AUTOMATIC);
13282
13283     if (!player->programmed_action)
13284       CheckSaveEngineSnapshot(player);
13285   }
13286 }
13287
13288 void ScrollScreen(struct PlayerInfo *player, int mode)
13289 {
13290   static DelayCounter screen_frame_counter = { 0 };
13291
13292   if (mode == SCROLL_INIT)
13293   {
13294     // set scrolling step size according to actual player's moving speed
13295     ScrollStepSize = TILEX / player->move_delay_value;
13296
13297     screen_frame_counter.count = FrameCounter;
13298     screen_frame_counter.value = 1;
13299
13300     ScreenMovDir = player->MovDir;
13301     ScreenMovPos = player->MovPos;
13302     ScreenGfxPos = ScrollStepSize * (ScreenMovPos / ScrollStepSize);
13303     return;
13304   }
13305   else if (!FrameReached(&screen_frame_counter))
13306     return;
13307
13308   if (ScreenMovPos)
13309   {
13310     ScreenMovPos += (ScreenMovPos > 0 ? -1 : 1) * ScrollStepSize;
13311     ScreenGfxPos = ScrollStepSize * (ScreenMovPos / ScrollStepSize);
13312     redraw_mask |= REDRAW_FIELD;
13313   }
13314   else
13315     ScreenMovDir = MV_NONE;
13316 }
13317
13318 void CheckNextToConditions(int x, int y)
13319 {
13320   int element = Tile[x][y];
13321
13322   if (IS_PLAYER(x, y))
13323     TestIfPlayerNextToCustomElement(x, y);
13324
13325   if (CAN_CHANGE_OR_HAS_ACTION(element) &&
13326       HAS_ANY_CHANGE_EVENT(element, CE_NEXT_TO_X))
13327     TestIfElementNextToCustomElement(x, y);
13328 }
13329
13330 void TestIfPlayerNextToCustomElement(int x, int y)
13331 {
13332   struct XY *xy = xy_topdown;
13333   static int trigger_sides[4][2] =
13334   {
13335     // center side       border side
13336     { CH_SIDE_TOP,      CH_SIDE_BOTTOM  },      // check top
13337     { CH_SIDE_LEFT,     CH_SIDE_RIGHT   },      // check left
13338     { CH_SIDE_RIGHT,    CH_SIDE_LEFT    },      // check right
13339     { CH_SIDE_BOTTOM,   CH_SIDE_TOP     }       // check bottom
13340   };
13341   int i;
13342
13343   if (!IS_PLAYER(x, y))
13344     return;
13345
13346   struct PlayerInfo *player = PLAYERINFO(x, y);
13347
13348   if (player->is_moving)
13349     return;
13350
13351   for (i = 0; i < NUM_DIRECTIONS; i++)
13352   {
13353     int xx = x + xy[i].x;
13354     int yy = y + xy[i].y;
13355     int border_side = trigger_sides[i][1];
13356     int border_element;
13357
13358     if (!IN_LEV_FIELD(xx, yy))
13359       continue;
13360
13361     if (IS_MOVING(xx, yy) || IS_BLOCKED(xx, yy))
13362       continue;         // center and border element not connected
13363
13364     border_element = Tile[xx][yy];
13365
13366     CheckElementChangeByPlayer(xx, yy, border_element, CE_NEXT_TO_PLAYER,
13367                                player->index_bit, border_side);
13368     CheckTriggeredElementChangeByPlayer(xx, yy, border_element,
13369                                         CE_PLAYER_NEXT_TO_X,
13370                                         player->index_bit, border_side);
13371
13372     /* use player element that is initially defined in the level playfield,
13373        not the player element that corresponds to the runtime player number
13374        (example: a level that contains EL_PLAYER_3 as the only player would
13375        incorrectly give EL_PLAYER_1 for "player->element_nr") */
13376
13377     CheckElementChangeBySide(xx, yy, border_element, player->initial_element,
13378                              CE_NEXT_TO_X, border_side);
13379   }
13380 }
13381
13382 void TestIfPlayerTouchesCustomElement(int x, int y)
13383 {
13384   struct XY *xy = xy_topdown;
13385   static int trigger_sides[4][2] =
13386   {
13387     // center side       border side
13388     { CH_SIDE_TOP,      CH_SIDE_BOTTOM  },      // check top
13389     { CH_SIDE_LEFT,     CH_SIDE_RIGHT   },      // check left
13390     { CH_SIDE_RIGHT,    CH_SIDE_LEFT    },      // check right
13391     { CH_SIDE_BOTTOM,   CH_SIDE_TOP     }       // check bottom
13392   };
13393   static int touch_dir[4] =
13394   {
13395     MV_LEFT | MV_RIGHT,
13396     MV_UP   | MV_DOWN,
13397     MV_UP   | MV_DOWN,
13398     MV_LEFT | MV_RIGHT
13399   };
13400   int center_element = Tile[x][y];      // should always be non-moving!
13401   int i;
13402
13403   for (i = 0; i < NUM_DIRECTIONS; i++)
13404   {
13405     int xx = x + xy[i].x;
13406     int yy = y + xy[i].y;
13407     int center_side = trigger_sides[i][0];
13408     int border_side = trigger_sides[i][1];
13409     int border_element;
13410
13411     if (!IN_LEV_FIELD(xx, yy))
13412       continue;
13413
13414     if (IS_PLAYER(x, y))                // player found at center element
13415     {
13416       struct PlayerInfo *player = PLAYERINFO(x, y);
13417
13418       if (game.engine_version < VERSION_IDENT(3,0,7,0))
13419         border_element = Tile[xx][yy];          // may be moving!
13420       else if (!IS_MOVING(xx, yy) && !IS_BLOCKED(xx, yy))
13421         border_element = Tile[xx][yy];
13422       else if (MovDir[xx][yy] & touch_dir[i])   // elements are touching
13423         border_element = MovingOrBlocked2Element(xx, yy);
13424       else
13425         continue;               // center and border element do not touch
13426
13427       CheckElementChangeByPlayer(xx, yy, border_element, CE_TOUCHED_BY_PLAYER,
13428                                  player->index_bit, border_side);
13429       CheckTriggeredElementChangeByPlayer(xx, yy, border_element,
13430                                           CE_PLAYER_TOUCHES_X,
13431                                           player->index_bit, border_side);
13432
13433       {
13434         /* use player element that is initially defined in the level playfield,
13435            not the player element that corresponds to the runtime player number
13436            (example: a level that contains EL_PLAYER_3 as the only player would
13437            incorrectly give EL_PLAYER_1 for "player->element_nr") */
13438         int player_element = PLAYERINFO(x, y)->initial_element;
13439
13440         CheckElementChangeBySide(xx, yy, border_element, player_element,
13441                                  CE_TOUCHING_X, border_side);
13442       }
13443     }
13444     else if (IS_PLAYER(xx, yy))         // player found at border element
13445     {
13446       struct PlayerInfo *player = PLAYERINFO(xx, yy);
13447
13448       if (game.engine_version >= VERSION_IDENT(3,0,7,0))
13449       {
13450         if (player->MovPos != 0 && !(player->MovDir & touch_dir[i]))
13451           continue;             // center and border element do not touch
13452       }
13453
13454       CheckElementChangeByPlayer(x, y, center_element, CE_TOUCHED_BY_PLAYER,
13455                                  player->index_bit, center_side);
13456       CheckTriggeredElementChangeByPlayer(x, y, center_element,
13457                                           CE_PLAYER_TOUCHES_X,
13458                                           player->index_bit, center_side);
13459
13460       {
13461         /* use player element that is initially defined in the level playfield,
13462            not the player element that corresponds to the runtime player number
13463            (example: a level that contains EL_PLAYER_3 as the only player would
13464            incorrectly give EL_PLAYER_1 for "player->element_nr") */
13465         int player_element = PLAYERINFO(xx, yy)->initial_element;
13466
13467         CheckElementChangeBySide(x, y, center_element, player_element,
13468                                  CE_TOUCHING_X, center_side);
13469       }
13470
13471       break;
13472     }
13473   }
13474 }
13475
13476 void TestIfElementNextToCustomElement(int x, int y)
13477 {
13478   struct XY *xy = xy_topdown;
13479   static int trigger_sides[4][2] =
13480   {
13481     // center side      border side
13482     { CH_SIDE_TOP,      CH_SIDE_BOTTOM  },      // check top
13483     { CH_SIDE_LEFT,     CH_SIDE_RIGHT   },      // check left
13484     { CH_SIDE_RIGHT,    CH_SIDE_LEFT    },      // check right
13485     { CH_SIDE_BOTTOM,   CH_SIDE_TOP     }       // check bottom
13486   };
13487   int center_element = Tile[x][y];      // should always be non-moving!
13488   int i;
13489
13490   if (IS_MOVING(x, y) || IS_BLOCKED(x, y))
13491     return;
13492
13493   for (i = 0; i < NUM_DIRECTIONS; i++)
13494   {
13495     int xx = x + xy[i].x;
13496     int yy = y + xy[i].y;
13497     int border_side = trigger_sides[i][1];
13498     int border_element;
13499
13500     if (!IN_LEV_FIELD(xx, yy))
13501       continue;
13502
13503     if (IS_MOVING(xx, yy) || IS_BLOCKED(xx, yy))
13504       continue;                 // center and border element not connected
13505
13506     border_element = Tile[xx][yy];
13507
13508     // check for change of center element (but change it only once)
13509     if (CheckElementChangeBySide(x, y, center_element, border_element,
13510                                  CE_NEXT_TO_X, border_side))
13511       break;
13512   }
13513 }
13514
13515 void TestIfElementTouchesCustomElement(int x, int y)
13516 {
13517   struct XY *xy = xy_topdown;
13518   static int trigger_sides[4][2] =
13519   {
13520     // center side      border side
13521     { CH_SIDE_TOP,      CH_SIDE_BOTTOM  },      // check top
13522     { CH_SIDE_LEFT,     CH_SIDE_RIGHT   },      // check left
13523     { CH_SIDE_RIGHT,    CH_SIDE_LEFT    },      // check right
13524     { CH_SIDE_BOTTOM,   CH_SIDE_TOP     }       // check bottom
13525   };
13526   static int touch_dir[4] =
13527   {
13528     MV_LEFT | MV_RIGHT,
13529     MV_UP   | MV_DOWN,
13530     MV_UP   | MV_DOWN,
13531     MV_LEFT | MV_RIGHT
13532   };
13533   boolean change_center_element = FALSE;
13534   int center_element = Tile[x][y];      // should always be non-moving!
13535   int border_element_old[NUM_DIRECTIONS];
13536   int i;
13537
13538   for (i = 0; i < NUM_DIRECTIONS; i++)
13539   {
13540     int xx = x + xy[i].x;
13541     int yy = y + xy[i].y;
13542     int border_element;
13543
13544     border_element_old[i] = -1;
13545
13546     if (!IN_LEV_FIELD(xx, yy))
13547       continue;
13548
13549     if (game.engine_version < VERSION_IDENT(3,0,7,0))
13550       border_element = Tile[xx][yy];    // may be moving!
13551     else if (!IS_MOVING(xx, yy) && !IS_BLOCKED(xx, yy))
13552       border_element = Tile[xx][yy];
13553     else if (MovDir[xx][yy] & touch_dir[i])     // elements are touching
13554       border_element = MovingOrBlocked2Element(xx, yy);
13555     else
13556       continue;                 // center and border element do not touch
13557
13558     border_element_old[i] = border_element;
13559   }
13560
13561   for (i = 0; i < NUM_DIRECTIONS; i++)
13562   {
13563     int xx = x + xy[i].x;
13564     int yy = y + xy[i].y;
13565     int center_side = trigger_sides[i][0];
13566     int border_element = border_element_old[i];
13567
13568     if (border_element == -1)
13569       continue;
13570
13571     // check for change of border element
13572     CheckElementChangeBySide(xx, yy, border_element, center_element,
13573                              CE_TOUCHING_X, center_side);
13574
13575     // (center element cannot be player, so we dont have to check this here)
13576   }
13577
13578   for (i = 0; i < NUM_DIRECTIONS; i++)
13579   {
13580     int xx = x + xy[i].x;
13581     int yy = y + xy[i].y;
13582     int border_side = trigger_sides[i][1];
13583     int border_element = border_element_old[i];
13584
13585     if (border_element == -1)
13586       continue;
13587
13588     // check for change of center element (but change it only once)
13589     if (!change_center_element)
13590       change_center_element =
13591         CheckElementChangeBySide(x, y, center_element, border_element,
13592                                  CE_TOUCHING_X, border_side);
13593
13594     if (IS_PLAYER(xx, yy))
13595     {
13596       /* use player element that is initially defined in the level playfield,
13597          not the player element that corresponds to the runtime player number
13598          (example: a level that contains EL_PLAYER_3 as the only player would
13599          incorrectly give EL_PLAYER_1 for "player->element_nr") */
13600       int player_element = PLAYERINFO(xx, yy)->initial_element;
13601
13602       CheckElementChangeBySide(x, y, center_element, player_element,
13603                                CE_TOUCHING_X, border_side);
13604     }
13605   }
13606 }
13607
13608 void TestIfElementHitsCustomElement(int x, int y, int direction)
13609 {
13610   int dx = (direction == MV_LEFT ? -1 : direction == MV_RIGHT ? +1 : 0);
13611   int dy = (direction == MV_UP   ? -1 : direction == MV_DOWN  ? +1 : 0);
13612   int hitx = x + dx, hity = y + dy;
13613   int hitting_element = Tile[x][y];
13614   int touched_element;
13615
13616   if (IN_LEV_FIELD(hitx, hity) && IS_FREE(hitx, hity))
13617     return;
13618
13619   touched_element = (IN_LEV_FIELD(hitx, hity) ?
13620                      MovingOrBlocked2Element(hitx, hity) : EL_STEELWALL);
13621
13622   if (IN_LEV_FIELD(hitx, hity))
13623   {
13624     int opposite_direction = MV_DIR_OPPOSITE(direction);
13625     int hitting_side = direction;
13626     int touched_side = opposite_direction;
13627     boolean object_hit = (!IS_MOVING(hitx, hity) ||
13628                           MovDir[hitx][hity] != direction ||
13629                           ABS(MovPos[hitx][hity]) <= TILEY / 2);
13630
13631     object_hit = TRUE;
13632
13633     if (object_hit)
13634     {
13635       CheckElementChangeBySide(x, y, hitting_element, touched_element,
13636                                CE_HITTING_X, touched_side);
13637
13638       CheckElementChangeBySide(hitx, hity, touched_element, hitting_element,
13639                                CE_HIT_BY_X, hitting_side);
13640
13641       CheckElementChangeBySide(hitx, hity, touched_element, hitting_element,
13642                                CE_HIT_BY_SOMETHING, opposite_direction);
13643
13644       if (IS_PLAYER(hitx, hity))
13645       {
13646         /* use player element that is initially defined in the level playfield,
13647            not the player element that corresponds to the runtime player number
13648            (example: a level that contains EL_PLAYER_3 as the only player would
13649            incorrectly give EL_PLAYER_1 for "player->element_nr") */
13650         int player_element = PLAYERINFO(hitx, hity)->initial_element;
13651
13652         CheckElementChangeBySide(x, y, hitting_element, player_element,
13653                                  CE_HITTING_X, touched_side);
13654       }
13655     }
13656   }
13657
13658   // "hitting something" is also true when hitting the playfield border
13659   CheckElementChangeBySide(x, y, hitting_element, touched_element,
13660                            CE_HITTING_SOMETHING, direction);
13661 }
13662
13663 void TestIfGoodThingHitsBadThing(int good_x, int good_y, int good_move_dir)
13664 {
13665   int i, kill_x = -1, kill_y = -1;
13666
13667   int bad_element = -1;
13668   struct XY *test_xy = xy_topdown;
13669   static int test_dir[4] =
13670   {
13671     MV_UP,
13672     MV_LEFT,
13673     MV_RIGHT,
13674     MV_DOWN
13675   };
13676
13677   for (i = 0; i < NUM_DIRECTIONS; i++)
13678   {
13679     int test_x, test_y, test_move_dir, test_element;
13680
13681     test_x = good_x + test_xy[i].x;
13682     test_y = good_y + test_xy[i].y;
13683
13684     if (!IN_LEV_FIELD(test_x, test_y))
13685       continue;
13686
13687     test_move_dir =
13688       (IS_MOVING(test_x, test_y) ? MovDir[test_x][test_y] : MV_NONE);
13689
13690     test_element = MovingOrBlocked2ElementIfNotLeaving(test_x, test_y);
13691
13692     /* 1st case: good thing is moving towards DONT_RUN_INTO style bad thing;
13693        2nd case: DONT_TOUCH style bad thing does not move away from good thing
13694     */
13695     if ((DONT_RUN_INTO(test_element) && good_move_dir == test_dir[i]) ||
13696         (DONT_TOUCH(test_element)    && test_move_dir != test_dir[i]))
13697     {
13698       kill_x = test_x;
13699       kill_y = test_y;
13700       bad_element = test_element;
13701
13702       break;
13703     }
13704   }
13705
13706   if (kill_x != -1 || kill_y != -1)
13707   {
13708     if (IS_PLAYER(good_x, good_y))
13709     {
13710       struct PlayerInfo *player = PLAYERINFO(good_x, good_y);
13711
13712       if (player->shield_deadly_time_left > 0 &&
13713           !IS_INDESTRUCTIBLE(bad_element))
13714         Bang(kill_x, kill_y);
13715       else if (!PLAYER_ENEMY_PROTECTED(good_x, good_y))
13716         KillPlayer(player);
13717     }
13718     else
13719       Bang(good_x, good_y);
13720   }
13721 }
13722
13723 void TestIfBadThingHitsGoodThing(int bad_x, int bad_y, int bad_move_dir)
13724 {
13725   int i, kill_x = -1, kill_y = -1;
13726   int bad_element = Tile[bad_x][bad_y];
13727   struct XY *test_xy = xy_topdown;
13728   static int touch_dir[4] =
13729   {
13730     MV_LEFT | MV_RIGHT,
13731     MV_UP   | MV_DOWN,
13732     MV_UP   | MV_DOWN,
13733     MV_LEFT | MV_RIGHT
13734   };
13735   static int test_dir[4] =
13736   {
13737     MV_UP,
13738     MV_LEFT,
13739     MV_RIGHT,
13740     MV_DOWN
13741   };
13742
13743   if (bad_element == EL_EXPLOSION)      // skip just exploding bad things
13744     return;
13745
13746   for (i = 0; i < NUM_DIRECTIONS; i++)
13747   {
13748     int test_x, test_y, test_move_dir, test_element;
13749
13750     test_x = bad_x + test_xy[i].x;
13751     test_y = bad_y + test_xy[i].y;
13752
13753     if (!IN_LEV_FIELD(test_x, test_y))
13754       continue;
13755
13756     test_move_dir =
13757       (IS_MOVING(test_x, test_y) ? MovDir[test_x][test_y] : MV_NONE);
13758
13759     test_element = Tile[test_x][test_y];
13760
13761     /* 1st case: good thing is moving towards DONT_RUN_INTO style bad thing;
13762        2nd case: DONT_TOUCH style bad thing does not move away from good thing
13763     */
13764     if ((DONT_RUN_INTO(bad_element) &&  bad_move_dir == test_dir[i]) ||
13765         (DONT_TOUCH(bad_element)    && test_move_dir != test_dir[i]))
13766     {
13767       // good thing is player or penguin that does not move away
13768       if (IS_PLAYER(test_x, test_y))
13769       {
13770         struct PlayerInfo *player = PLAYERINFO(test_x, test_y);
13771
13772         if (bad_element == EL_ROBOT && player->is_moving)
13773           continue;     // robot does not kill player if he is moving
13774
13775         if (game.engine_version >= VERSION_IDENT(3,0,7,0))
13776         {
13777           if (player->MovPos != 0 && !(player->MovDir & touch_dir[i]))
13778             continue;           // center and border element do not touch
13779         }
13780
13781         kill_x = test_x;
13782         kill_y = test_y;
13783
13784         break;
13785       }
13786       else if (test_element == EL_PENGUIN)
13787       {
13788         kill_x = test_x;
13789         kill_y = test_y;
13790
13791         break;
13792       }
13793     }
13794   }
13795
13796   if (kill_x != -1 || kill_y != -1)
13797   {
13798     if (IS_PLAYER(kill_x, kill_y))
13799     {
13800       struct PlayerInfo *player = PLAYERINFO(kill_x, kill_y);
13801
13802       if (player->shield_deadly_time_left > 0 &&
13803           !IS_INDESTRUCTIBLE(bad_element))
13804         Bang(bad_x, bad_y);
13805       else if (!PLAYER_ENEMY_PROTECTED(kill_x, kill_y))
13806         KillPlayer(player);
13807     }
13808     else
13809       Bang(kill_x, kill_y);
13810   }
13811 }
13812
13813 void TestIfGoodThingGetsHitByBadThing(int bad_x, int bad_y, int bad_move_dir)
13814 {
13815   int bad_element = Tile[bad_x][bad_y];
13816   int dx = (bad_move_dir == MV_LEFT ? -1 : bad_move_dir == MV_RIGHT ? +1 : 0);
13817   int dy = (bad_move_dir == MV_UP   ? -1 : bad_move_dir == MV_DOWN  ? +1 : 0);
13818   int test_x = bad_x + dx, test_y = bad_y + dy;
13819   int test_move_dir, test_element;
13820   int kill_x = -1, kill_y = -1;
13821
13822   if (!IN_LEV_FIELD(test_x, test_y))
13823     return;
13824
13825   test_move_dir =
13826     (IS_MOVING(test_x, test_y) ? MovDir[test_x][test_y] : MV_NONE);
13827
13828   test_element = Tile[test_x][test_y];
13829
13830   if (test_move_dir != bad_move_dir)
13831   {
13832     // good thing can be player or penguin that does not move away
13833     if (IS_PLAYER(test_x, test_y))
13834     {
13835       struct PlayerInfo *player = PLAYERINFO(test_x, test_y);
13836
13837       /* (note: in comparison to DONT_RUN_TO and DONT_TOUCH, also handle the
13838          player as being hit when he is moving towards the bad thing, because
13839          the "get hit by" condition would be lost after the player stops) */
13840       if (player->MovPos != 0 && player->MovDir == bad_move_dir)
13841         return;         // player moves away from bad thing
13842
13843       kill_x = test_x;
13844       kill_y = test_y;
13845     }
13846     else if (test_element == EL_PENGUIN)
13847     {
13848       kill_x = test_x;
13849       kill_y = test_y;
13850     }
13851   }
13852
13853   if (kill_x != -1 || kill_y != -1)
13854   {
13855     if (IS_PLAYER(kill_x, kill_y))
13856     {
13857       struct PlayerInfo *player = PLAYERINFO(kill_x, kill_y);
13858
13859       if (player->shield_deadly_time_left > 0 &&
13860           !IS_INDESTRUCTIBLE(bad_element))
13861         Bang(bad_x, bad_y);
13862       else if (!PLAYER_ENEMY_PROTECTED(kill_x, kill_y))
13863         KillPlayer(player);
13864     }
13865     else
13866       Bang(kill_x, kill_y);
13867   }
13868 }
13869
13870 void TestIfPlayerTouchesBadThing(int x, int y)
13871 {
13872   TestIfGoodThingHitsBadThing(x, y, MV_NONE);
13873 }
13874
13875 void TestIfPlayerRunsIntoBadThing(int x, int y, int move_dir)
13876 {
13877   TestIfGoodThingHitsBadThing(x, y, move_dir);
13878 }
13879
13880 void TestIfBadThingTouchesPlayer(int x, int y)
13881 {
13882   TestIfBadThingHitsGoodThing(x, y, MV_NONE);
13883 }
13884
13885 void TestIfBadThingRunsIntoPlayer(int x, int y, int move_dir)
13886 {
13887   TestIfBadThingHitsGoodThing(x, y, move_dir);
13888 }
13889
13890 void TestIfFriendTouchesBadThing(int x, int y)
13891 {
13892   TestIfGoodThingHitsBadThing(x, y, MV_NONE);
13893 }
13894
13895 void TestIfBadThingTouchesFriend(int x, int y)
13896 {
13897   TestIfBadThingHitsGoodThing(x, y, MV_NONE);
13898 }
13899
13900 void TestIfBadThingTouchesOtherBadThing(int bad_x, int bad_y)
13901 {
13902   int i, kill_x = bad_x, kill_y = bad_y;
13903   struct XY *xy = xy_topdown;
13904
13905   for (i = 0; i < NUM_DIRECTIONS; i++)
13906   {
13907     int x, y, element;
13908
13909     x = bad_x + xy[i].x;
13910     y = bad_y + xy[i].y;
13911     if (!IN_LEV_FIELD(x, y))
13912       continue;
13913
13914     element = Tile[x][y];
13915     if (IS_AMOEBOID(element) || element == EL_GAME_OF_LIFE ||
13916         element == EL_AMOEBA_GROWING || element == EL_AMOEBA_DROP)
13917     {
13918       kill_x = x;
13919       kill_y = y;
13920       break;
13921     }
13922   }
13923
13924   if (kill_x != bad_x || kill_y != bad_y)
13925     Bang(bad_x, bad_y);
13926 }
13927
13928 void KillPlayer(struct PlayerInfo *player)
13929 {
13930   int jx = player->jx, jy = player->jy;
13931
13932   if (!player->active)
13933     return;
13934
13935 #if 0
13936   Debug("game:playing:KillPlayer",
13937         "0: killed == %d, active == %d, reanimated == %d",
13938         player->killed, player->active, player->reanimated);
13939 #endif
13940
13941   /* the following code was introduced to prevent an infinite loop when calling
13942      -> Bang()
13943      -> CheckTriggeredElementChangeExt()
13944      -> ExecuteCustomElementAction()
13945      -> KillPlayer()
13946      -> (infinitely repeating the above sequence of function calls)
13947      which occurs when killing the player while having a CE with the setting
13948      "kill player X when explosion of <player X>"; the solution using a new
13949      field "player->killed" was chosen for backwards compatibility, although
13950      clever use of the fields "player->active" etc. would probably also work */
13951 #if 1
13952   if (player->killed)
13953     return;
13954 #endif
13955
13956   player->killed = TRUE;
13957
13958   // remove accessible field at the player's position
13959   RemoveField(jx, jy);
13960
13961   // deactivate shield (else Bang()/Explode() would not work right)
13962   player->shield_normal_time_left = 0;
13963   player->shield_deadly_time_left = 0;
13964
13965 #if 0
13966   Debug("game:playing:KillPlayer",
13967         "1: killed == %d, active == %d, reanimated == %d",
13968         player->killed, player->active, player->reanimated);
13969 #endif
13970
13971   Bang(jx, jy);
13972
13973 #if 0
13974   Debug("game:playing:KillPlayer",
13975         "2: killed == %d, active == %d, reanimated == %d",
13976         player->killed, player->active, player->reanimated);
13977 #endif
13978
13979   if (player->reanimated)       // killed player may have been reanimated
13980     player->killed = player->reanimated = FALSE;
13981   else
13982     BuryPlayer(player);
13983 }
13984
13985 static void KillPlayerUnlessEnemyProtected(int x, int y)
13986 {
13987   if (!PLAYER_ENEMY_PROTECTED(x, y))
13988     KillPlayer(PLAYERINFO(x, y));
13989 }
13990
13991 static void KillPlayerUnlessExplosionProtected(int x, int y)
13992 {
13993   if (!PLAYER_EXPLOSION_PROTECTED(x, y))
13994     KillPlayer(PLAYERINFO(x, y));
13995 }
13996
13997 void BuryPlayer(struct PlayerInfo *player)
13998 {
13999   int jx = player->jx, jy = player->jy;
14000
14001   if (!player->active)
14002     return;
14003
14004   PlayLevelSoundElementAction(jx, jy, player->artwork_element, ACTION_DYING);
14005
14006   RemovePlayer(player);
14007
14008   player->buried = TRUE;
14009
14010   if (game.all_players_gone)
14011     game.GameOver = TRUE;
14012 }
14013
14014 void RemovePlayer(struct PlayerInfo *player)
14015 {
14016   int jx = player->jx, jy = player->jy;
14017   int i, found = FALSE;
14018
14019   player->present = FALSE;
14020   player->active = FALSE;
14021
14022   // required for some CE actions (even if the player is not active anymore)
14023   player->MovPos = 0;
14024
14025   if (!ExplodeField[jx][jy])
14026     StorePlayer[jx][jy] = 0;
14027
14028   if (player->is_moving)
14029     TEST_DrawLevelField(player->last_jx, player->last_jy);
14030
14031   for (i = 0; i < MAX_PLAYERS; i++)
14032     if (stored_player[i].active)
14033       found = TRUE;
14034
14035   if (!found)
14036   {
14037     game.all_players_gone = TRUE;
14038     game.GameOver = TRUE;
14039   }
14040
14041   game.exit_x = game.robot_wheel_x = jx;
14042   game.exit_y = game.robot_wheel_y = jy;
14043 }
14044
14045 void ExitPlayer(struct PlayerInfo *player)
14046 {
14047   DrawPlayer(player);   // needed here only to cleanup last field
14048   RemovePlayer(player);
14049
14050   if (game.players_still_needed > 0)
14051     game.players_still_needed--;
14052 }
14053
14054 static void SetFieldForSnapping(int x, int y, int element, int direction,
14055                                 int player_index_bit)
14056 {
14057   struct ElementInfo *ei = &element_info[element];
14058   int direction_bit = MV_DIR_TO_BIT(direction);
14059   int graphic_snapping = ei->direction_graphic[ACTION_SNAPPING][direction_bit];
14060   int action = (graphic_snapping != IMG_EMPTY_SPACE ? ACTION_SNAPPING :
14061                 IS_DIGGABLE(element) ? ACTION_DIGGING : ACTION_COLLECTING);
14062
14063   Tile[x][y] = EL_ELEMENT_SNAPPING;
14064   MovDelay[x][y] = MOVE_DELAY_NORMAL_SPEED + 1 - 1;
14065   MovDir[x][y] = direction;
14066   Store[x][y] = element;
14067   Store2[x][y] = player_index_bit;
14068
14069   ResetGfxAnimation(x, y);
14070
14071   GfxElement[x][y] = element;
14072   GfxAction[x][y] = action;
14073   GfxDir[x][y] = direction;
14074   GfxFrame[x][y] = -1;
14075 }
14076
14077 static void TestFieldAfterSnapping(int x, int y, int element, int direction,
14078                                    int player_index_bit)
14079 {
14080   TestIfElementTouchesCustomElement(x, y);      // for empty space
14081
14082   if (level.finish_dig_collect)
14083   {
14084     int dig_side = MV_DIR_OPPOSITE(direction);
14085     int change_event = (IS_DIGGABLE(element) ? CE_PLAYER_DIGS_X :
14086                         CE_PLAYER_COLLECTS_X);
14087
14088     CheckTriggeredElementChangeByPlayer(x, y, element, change_event,
14089                                         player_index_bit, dig_side);
14090     CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_SNAPS_X,
14091                                         player_index_bit, dig_side);
14092   }
14093 }
14094
14095 /*
14096   =============================================================================
14097   checkDiagonalPushing()
14098   -----------------------------------------------------------------------------
14099   check if diagonal input device direction results in pushing of object
14100   (by checking if the alternative direction is walkable, diggable, ...)
14101   =============================================================================
14102 */
14103
14104 static boolean checkDiagonalPushing(struct PlayerInfo *player,
14105                                     int x, int y, int real_dx, int real_dy)
14106 {
14107   int jx, jy, dx, dy, xx, yy;
14108
14109   if (real_dx == 0 || real_dy == 0)     // no diagonal direction => push
14110     return TRUE;
14111
14112   // diagonal direction: check alternative direction
14113   jx = player->jx;
14114   jy = player->jy;
14115   dx = x - jx;
14116   dy = y - jy;
14117   xx = jx + (dx == 0 ? real_dx : 0);
14118   yy = jy + (dy == 0 ? real_dy : 0);
14119
14120   return (!IN_LEV_FIELD(xx, yy) || IS_SOLID_FOR_PUSHING(Tile[xx][yy]));
14121 }
14122
14123 /*
14124   =============================================================================
14125   DigField()
14126   -----------------------------------------------------------------------------
14127   x, y:                 field next to player (non-diagonal) to try to dig to
14128   real_dx, real_dy:     direction as read from input device (can be diagonal)
14129   =============================================================================
14130 */
14131
14132 static int DigField(struct PlayerInfo *player,
14133                     int oldx, int oldy, int x, int y,
14134                     int real_dx, int real_dy, int mode)
14135 {
14136   boolean is_player = (IS_PLAYER(oldx, oldy) || mode != DF_DIG);
14137   boolean player_was_pushing = player->is_pushing;
14138   boolean player_can_move = (!player->cannot_move && mode != DF_SNAP);
14139   boolean player_can_move_or_snap = (!player->cannot_move || mode == DF_SNAP);
14140   int jx = oldx, jy = oldy;
14141   int dx = x - jx, dy = y - jy;
14142   int nextx = x + dx, nexty = y + dy;
14143   int move_direction = (dx == -1 ? MV_LEFT  :
14144                         dx == +1 ? MV_RIGHT :
14145                         dy == -1 ? MV_UP    :
14146                         dy == +1 ? MV_DOWN  : MV_NONE);
14147   int opposite_direction = MV_DIR_OPPOSITE(move_direction);
14148   int dig_side = MV_DIR_OPPOSITE(move_direction);
14149   int old_element = Tile[jx][jy];
14150   int element = MovingOrBlocked2ElementIfNotLeaving(x, y);
14151   int collect_count;
14152
14153   if (is_player)                // function can also be called by EL_PENGUIN
14154   {
14155     if (player->MovPos == 0)
14156     {
14157       player->is_digging = FALSE;
14158       player->is_collecting = FALSE;
14159     }
14160
14161     if (player->MovPos == 0)    // last pushing move finished
14162       player->is_pushing = FALSE;
14163
14164     if (mode == DF_NO_PUSH)     // player just stopped pushing
14165     {
14166       player->is_switching = FALSE;
14167       player->push_delay = -1;
14168
14169       return MP_NO_ACTION;
14170     }
14171   }
14172   if (IS_TUBE(Back[jx][jy]) && game.engine_version >= VERSION_IDENT(2,2,0,0))
14173     old_element = Back[jx][jy];
14174
14175   // in case of element dropped at player position, check background
14176   else if (Back[jx][jy] != EL_EMPTY &&
14177            game.engine_version >= VERSION_IDENT(2,2,0,0))
14178     old_element = Back[jx][jy];
14179
14180   if (IS_WALKABLE(old_element) && !ACCESS_FROM(old_element, move_direction))
14181     return MP_NO_ACTION;        // field has no opening in this direction
14182
14183   if (IS_PASSABLE(old_element) && !ACCESS_FROM(old_element, opposite_direction))
14184     return MP_NO_ACTION;        // field has no opening in this direction
14185
14186   if (player_can_move && element == EL_ACID && move_direction == MV_DOWN)
14187   {
14188     SplashAcid(x, y);
14189
14190     Tile[jx][jy] = player->artwork_element;
14191     InitMovingField(jx, jy, MV_DOWN);
14192     Store[jx][jy] = EL_ACID;
14193     ContinueMoving(jx, jy);
14194     BuryPlayer(player);
14195
14196     return MP_DONT_RUN_INTO;
14197   }
14198
14199   if (player_can_move && DONT_RUN_INTO(element))
14200   {
14201     TestIfPlayerRunsIntoBadThing(jx, jy, player->MovDir);
14202
14203     return MP_DONT_RUN_INTO;
14204   }
14205
14206   if (IS_MOVING(x, y) || IS_PLAYER(x, y))
14207     return MP_NO_ACTION;
14208
14209   collect_count = element_info[element].collect_count_initial;
14210
14211   if (!is_player && !IS_COLLECTIBLE(element))   // penguin cannot collect it
14212     return MP_NO_ACTION;
14213
14214   if (game.engine_version < VERSION_IDENT(2,2,0,0))
14215     player_can_move = player_can_move_or_snap;
14216
14217   if (mode == DF_SNAP && !IS_SNAPPABLE(element) &&
14218       game.engine_version >= VERSION_IDENT(2,2,0,0))
14219   {
14220     CheckElementChangeByPlayer(x, y, element, CE_SNAPPED_BY_PLAYER,
14221                                player->index_bit, dig_side);
14222     CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_SNAPS_X,
14223                                         player->index_bit, dig_side);
14224
14225     if (element == EL_DC_LANDMINE)
14226       Bang(x, y);
14227
14228     if (Tile[x][y] != element)          // field changed by snapping
14229       return MP_ACTION;
14230
14231     return MP_NO_ACTION;
14232   }
14233
14234   if (player->gravity && is_player && !player->is_auto_moving &&
14235       canFallDown(player) && move_direction != MV_DOWN &&
14236       !canMoveToValidFieldWithGravity(jx, jy, move_direction))
14237     return MP_NO_ACTION;        // player cannot walk here due to gravity
14238
14239   if (player_can_move &&
14240       IS_WALKABLE(element) && ACCESS_FROM(element, opposite_direction))
14241   {
14242     int sound_element = SND_ELEMENT(element);
14243     int sound_action = ACTION_WALKING;
14244
14245     if (IS_RND_GATE(element))
14246     {
14247       if (!player->key[RND_GATE_NR(element)])
14248         return MP_NO_ACTION;
14249     }
14250     else if (IS_RND_GATE_GRAY(element))
14251     {
14252       if (!player->key[RND_GATE_GRAY_NR(element)])
14253         return MP_NO_ACTION;
14254     }
14255     else if (IS_RND_GATE_GRAY_ACTIVE(element))
14256     {
14257       if (!player->key[RND_GATE_GRAY_ACTIVE_NR(element)])
14258         return MP_NO_ACTION;
14259     }
14260     else if (element == EL_EXIT_OPEN ||
14261              element == EL_EM_EXIT_OPEN ||
14262              element == EL_EM_EXIT_OPENING ||
14263              element == EL_STEEL_EXIT_OPEN ||
14264              element == EL_EM_STEEL_EXIT_OPEN ||
14265              element == EL_EM_STEEL_EXIT_OPENING ||
14266              element == EL_SP_EXIT_OPEN ||
14267              element == EL_SP_EXIT_OPENING)
14268     {
14269       sound_action = ACTION_PASSING;    // player is passing exit
14270     }
14271     else if (element == EL_EMPTY)
14272     {
14273       sound_action = ACTION_MOVING;             // nothing to walk on
14274     }
14275
14276     // play sound from background or player, whatever is available
14277     if (element_info[sound_element].sound[sound_action] != SND_UNDEFINED)
14278       PlayLevelSoundElementAction(x, y, sound_element, sound_action);
14279     else
14280       PlayLevelSoundElementAction(x, y, player->artwork_element, sound_action);
14281   }
14282   else if (player_can_move &&
14283            IS_PASSABLE(element) && canPassField(x, y, move_direction))
14284   {
14285     if (!ACCESS_FROM(element, opposite_direction))
14286       return MP_NO_ACTION;      // field not accessible from this direction
14287
14288     if (CAN_MOVE(element))      // only fixed elements can be passed!
14289       return MP_NO_ACTION;
14290
14291     if (IS_EM_GATE(element))
14292     {
14293       if (!player->key[EM_GATE_NR(element)])
14294         return MP_NO_ACTION;
14295     }
14296     else if (IS_EM_GATE_GRAY(element))
14297     {
14298       if (!player->key[EM_GATE_GRAY_NR(element)])
14299         return MP_NO_ACTION;
14300     }
14301     else if (IS_EM_GATE_GRAY_ACTIVE(element))
14302     {
14303       if (!player->key[EM_GATE_GRAY_ACTIVE_NR(element)])
14304         return MP_NO_ACTION;
14305     }
14306     else if (IS_EMC_GATE(element))
14307     {
14308       if (!player->key[EMC_GATE_NR(element)])
14309         return MP_NO_ACTION;
14310     }
14311     else if (IS_EMC_GATE_GRAY(element))
14312     {
14313       if (!player->key[EMC_GATE_GRAY_NR(element)])
14314         return MP_NO_ACTION;
14315     }
14316     else if (IS_EMC_GATE_GRAY_ACTIVE(element))
14317     {
14318       if (!player->key[EMC_GATE_GRAY_ACTIVE_NR(element)])
14319         return MP_NO_ACTION;
14320     }
14321     else if (element == EL_DC_GATE_WHITE ||
14322              element == EL_DC_GATE_WHITE_GRAY ||
14323              element == EL_DC_GATE_WHITE_GRAY_ACTIVE)
14324     {
14325       if (player->num_white_keys == 0)
14326         return MP_NO_ACTION;
14327
14328       player->num_white_keys--;
14329     }
14330     else if (IS_SP_PORT(element))
14331     {
14332       if (element == EL_SP_GRAVITY_PORT_LEFT ||
14333           element == EL_SP_GRAVITY_PORT_RIGHT ||
14334           element == EL_SP_GRAVITY_PORT_UP ||
14335           element == EL_SP_GRAVITY_PORT_DOWN)
14336         player->gravity = !player->gravity;
14337       else if (element == EL_SP_GRAVITY_ON_PORT_LEFT ||
14338                element == EL_SP_GRAVITY_ON_PORT_RIGHT ||
14339                element == EL_SP_GRAVITY_ON_PORT_UP ||
14340                element == EL_SP_GRAVITY_ON_PORT_DOWN)
14341         player->gravity = TRUE;
14342       else if (element == EL_SP_GRAVITY_OFF_PORT_LEFT ||
14343                element == EL_SP_GRAVITY_OFF_PORT_RIGHT ||
14344                element == EL_SP_GRAVITY_OFF_PORT_UP ||
14345                element == EL_SP_GRAVITY_OFF_PORT_DOWN)
14346         player->gravity = FALSE;
14347     }
14348
14349     // automatically move to the next field with double speed
14350     player->programmed_action = move_direction;
14351
14352     if (player->move_delay_reset_counter == 0)
14353     {
14354       player->move_delay_reset_counter = 2;     // two double speed steps
14355
14356       DOUBLE_PLAYER_SPEED(player);
14357     }
14358
14359     PlayLevelSoundAction(x, y, ACTION_PASSING);
14360   }
14361   else if (player_can_move_or_snap && IS_DIGGABLE(element))
14362   {
14363     RemoveField(x, y);
14364
14365     if (mode != DF_SNAP)
14366     {
14367       GfxElement[x][y] = GFX_ELEMENT(element);
14368       player->is_digging = TRUE;
14369     }
14370
14371     PlayLevelSoundElementAction(x, y, element, ACTION_DIGGING);
14372
14373     // use old behaviour for old levels (digging)
14374     if (!level.finish_dig_collect)
14375     {
14376       CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_DIGS_X,
14377                                           player->index_bit, dig_side);
14378
14379       // if digging triggered player relocation, finish digging tile
14380       if (mode == DF_DIG && (player->jx != jx || player->jy != jy))
14381         SetFieldForSnapping(x, y, element, move_direction, player->index_bit);
14382     }
14383
14384     if (mode == DF_SNAP)
14385     {
14386       if (level.block_snap_field)
14387         SetFieldForSnapping(x, y, element, move_direction, player->index_bit);
14388       else
14389         TestFieldAfterSnapping(x, y, element, move_direction, player->index_bit);
14390
14391       // use old behaviour for old levels (snapping)
14392       if (!level.finish_dig_collect)
14393         CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_SNAPS_X,
14394                                             player->index_bit, dig_side);
14395     }
14396   }
14397   else if (player_can_move_or_snap && IS_COLLECTIBLE(element))
14398   {
14399     RemoveField(x, y);
14400
14401     if (is_player && mode != DF_SNAP)
14402     {
14403       GfxElement[x][y] = element;
14404       player->is_collecting = TRUE;
14405     }
14406
14407     if (element == EL_SPEED_PILL)
14408     {
14409       player->move_delay_value = MOVE_DELAY_HIGH_SPEED;
14410     }
14411     else if (element == EL_EXTRA_TIME && level.time > 0)
14412     {
14413       TimeLeft += level.extra_time;
14414
14415       game_panel_controls[GAME_PANEL_TIME].value = TimeLeft;
14416
14417       DisplayGameControlValues();
14418     }
14419     else if (element == EL_SHIELD_NORMAL || element == EL_SHIELD_DEADLY)
14420     {
14421       int shield_time = (element == EL_SHIELD_DEADLY ?
14422                          level.shield_deadly_time :
14423                          level.shield_normal_time);
14424
14425       player->shield_normal_time_left += shield_time;
14426       if (element == EL_SHIELD_DEADLY)
14427         player->shield_deadly_time_left += shield_time;
14428     }
14429     else if (element == EL_DYNAMITE ||
14430              element == EL_EM_DYNAMITE ||
14431              element == EL_SP_DISK_RED)
14432     {
14433       if (player->inventory_size < MAX_INVENTORY_SIZE)
14434         player->inventory_element[player->inventory_size++] = element;
14435
14436       DrawGameDoorValues();
14437     }
14438     else if (element == EL_DYNABOMB_INCREASE_NUMBER)
14439     {
14440       player->dynabomb_count++;
14441       player->dynabombs_left++;
14442     }
14443     else if (element == EL_DYNABOMB_INCREASE_SIZE)
14444     {
14445       player->dynabomb_size++;
14446     }
14447     else if (element == EL_DYNABOMB_INCREASE_POWER)
14448     {
14449       player->dynabomb_xl = TRUE;
14450     }
14451     else if (IS_KEY(element))
14452     {
14453       player->key[KEY_NR(element)] = TRUE;
14454
14455       DrawGameDoorValues();
14456     }
14457     else if (element == EL_DC_KEY_WHITE)
14458     {
14459       player->num_white_keys++;
14460
14461       // display white keys?
14462       // DrawGameDoorValues();
14463     }
14464     else if (IS_ENVELOPE(element))
14465     {
14466       boolean wait_for_snapping = (mode == DF_SNAP && level.block_snap_field);
14467
14468       if (!wait_for_snapping)
14469         player->show_envelope = element;
14470     }
14471     else if (element == EL_EMC_LENSES)
14472     {
14473       game.lenses_time_left = level.lenses_time * FRAMES_PER_SECOND;
14474
14475       RedrawAllInvisibleElementsForLenses();
14476     }
14477     else if (element == EL_EMC_MAGNIFIER)
14478     {
14479       game.magnify_time_left = level.magnify_time * FRAMES_PER_SECOND;
14480
14481       RedrawAllInvisibleElementsForMagnifier();
14482     }
14483     else if (IS_DROPPABLE(element) ||
14484              IS_THROWABLE(element))     // can be collected and dropped
14485     {
14486       int i;
14487
14488       if (collect_count == 0)
14489         player->inventory_infinite_element = element;
14490       else
14491         for (i = 0; i < collect_count; i++)
14492           if (player->inventory_size < MAX_INVENTORY_SIZE)
14493             player->inventory_element[player->inventory_size++] = element;
14494
14495       DrawGameDoorValues();
14496     }
14497     else if (collect_count > 0)
14498     {
14499       game.gems_still_needed -= collect_count;
14500       if (game.gems_still_needed < 0)
14501         game.gems_still_needed = 0;
14502
14503       game.snapshot.collected_item = TRUE;
14504
14505       game_panel_controls[GAME_PANEL_GEMS].value = game.gems_still_needed;
14506
14507       DisplayGameControlValues();
14508     }
14509
14510     RaiseScoreElement(element);
14511     PlayLevelSoundElementAction(x, y, element, ACTION_COLLECTING);
14512
14513     // use old behaviour for old levels (collecting)
14514     if (!level.finish_dig_collect && is_player)
14515     {
14516       CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_COLLECTS_X,
14517                                           player->index_bit, dig_side);
14518
14519       // if collecting triggered player relocation, finish collecting tile
14520       if (mode == DF_DIG && (player->jx != jx || player->jy != jy))
14521         SetFieldForSnapping(x, y, element, move_direction, player->index_bit);
14522     }
14523
14524     if (mode == DF_SNAP)
14525     {
14526       if (level.block_snap_field)
14527         SetFieldForSnapping(x, y, element, move_direction, player->index_bit);
14528       else
14529         TestFieldAfterSnapping(x, y, element, move_direction, player->index_bit);
14530
14531       // use old behaviour for old levels (snapping)
14532       if (!level.finish_dig_collect)
14533         CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_SNAPS_X,
14534                                             player->index_bit, dig_side);
14535     }
14536   }
14537   else if (player_can_move_or_snap && IS_PUSHABLE(element))
14538   {
14539     if (mode == DF_SNAP && element != EL_BD_ROCK)
14540       return MP_NO_ACTION;
14541
14542     if (CAN_FALL(element) && dy)
14543       return MP_NO_ACTION;
14544
14545     if (CAN_FALL(element) && IN_LEV_FIELD(x, y + 1) && IS_FREE(x, y + 1) &&
14546         !(element == EL_SPRING && level.use_spring_bug))
14547       return MP_NO_ACTION;
14548
14549     if (CAN_MOVE(element) && GET_MAX_MOVE_DELAY(element) == 0 &&
14550         ((move_direction & MV_VERTICAL &&
14551           ((element_info[element].move_pattern & MV_LEFT &&
14552             IN_LEV_FIELD(x - 1, y) && IS_FREE(x - 1, y)) ||
14553            (element_info[element].move_pattern & MV_RIGHT &&
14554             IN_LEV_FIELD(x + 1, y) && IS_FREE(x + 1, y)))) ||
14555          (move_direction & MV_HORIZONTAL &&
14556           ((element_info[element].move_pattern & MV_UP &&
14557             IN_LEV_FIELD(x, y - 1) && IS_FREE(x, y - 1)) ||
14558            (element_info[element].move_pattern & MV_DOWN &&
14559             IN_LEV_FIELD(x, y + 1) && IS_FREE(x, y + 1))))))
14560       return MP_NO_ACTION;
14561
14562     // do not push elements already moving away faster than player
14563     if (CAN_MOVE(element) && MovDir[x][y] == move_direction &&
14564         ABS(getElementMoveStepsize(x, y)) > MOVE_STEPSIZE_NORMAL)
14565       return MP_NO_ACTION;
14566
14567     if (game.engine_version >= VERSION_IDENT(3,1,0,0))
14568     {
14569       if (player->push_delay_value == -1 || !player_was_pushing)
14570         player->push_delay_value = GET_NEW_PUSH_DELAY(element);
14571     }
14572     else if (game.engine_version >= VERSION_IDENT(3,0,7,1))
14573     {
14574       if (player->push_delay_value == -1)
14575         player->push_delay_value = GET_NEW_PUSH_DELAY(element);
14576     }
14577     else if (game.engine_version >= VERSION_IDENT(2,2,0,7))
14578     {
14579       if (!player->is_pushing)
14580         player->push_delay_value = GET_NEW_PUSH_DELAY(element);
14581     }
14582
14583     player->is_pushing = TRUE;
14584     player->is_active = TRUE;
14585
14586     if (!(IN_LEV_FIELD(nextx, nexty) &&
14587           (IS_FREE(nextx, nexty) ||
14588            (IS_SB_ELEMENT(element) &&
14589             Tile[nextx][nexty] == EL_SOKOBAN_FIELD_EMPTY) ||
14590            (IS_CUSTOM_ELEMENT(element) &&
14591             CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, nextx, nexty)))))
14592       return MP_NO_ACTION;
14593
14594     if (!checkDiagonalPushing(player, x, y, real_dx, real_dy))
14595       return MP_NO_ACTION;
14596
14597     if (player->push_delay == -1)       // new pushing; restart delay
14598       player->push_delay = 0;
14599
14600     if (player->push_delay < player->push_delay_value &&
14601         !(tape.playing && tape.file_version < FILE_VERSION_2_0) &&
14602         element != EL_SPRING && element != EL_BALLOON)
14603     {
14604       // make sure that there is no move delay before next try to push
14605       if (game.engine_version >= VERSION_IDENT(3,0,7,1))
14606         player->move_delay = 0;
14607
14608       return MP_NO_ACTION;
14609     }
14610
14611     if (IS_CUSTOM_ELEMENT(element) &&
14612         CUSTOM_ELEMENT_CAN_ENTER_FIELD(element, nextx, nexty))
14613     {
14614       if (!DigFieldByCE(nextx, nexty, element))
14615         return MP_NO_ACTION;
14616     }
14617
14618     if (IS_SB_ELEMENT(element))
14619     {
14620       boolean sokoban_task_solved = FALSE;
14621
14622       if (element == EL_SOKOBAN_FIELD_FULL)
14623       {
14624         Back[x][y] = EL_SOKOBAN_FIELD_EMPTY;
14625
14626         IncrementSokobanFieldsNeeded();
14627         IncrementSokobanObjectsNeeded();
14628       }
14629
14630       if (Tile[nextx][nexty] == EL_SOKOBAN_FIELD_EMPTY)
14631       {
14632         Back[nextx][nexty] = EL_SOKOBAN_FIELD_EMPTY;
14633
14634         DecrementSokobanFieldsNeeded();
14635         DecrementSokobanObjectsNeeded();
14636
14637         // sokoban object was pushed from empty field to sokoban field
14638         if (Back[x][y] == EL_EMPTY)
14639           sokoban_task_solved = TRUE;
14640       }
14641
14642       Tile[x][y] = EL_SOKOBAN_OBJECT;
14643
14644       if (Back[x][y] == Back[nextx][nexty])
14645         PlayLevelSoundAction(x, y, ACTION_PUSHING);
14646       else if (Back[x][y] != 0)
14647         PlayLevelSoundElementAction(x, y, EL_SOKOBAN_FIELD_FULL,
14648                                     ACTION_EMPTYING);
14649       else
14650         PlayLevelSoundElementAction(nextx, nexty, EL_SOKOBAN_FIELD_EMPTY,
14651                                     ACTION_FILLING);
14652
14653       if (sokoban_task_solved &&
14654           game.sokoban_fields_still_needed == 0 &&
14655           game.sokoban_objects_still_needed == 0 &&
14656           level.auto_exit_sokoban)
14657       {
14658         game.players_still_needed = 0;
14659
14660         LevelSolved();
14661
14662         PlaySound(SND_GAME_SOKOBAN_SOLVING);
14663       }
14664     }
14665     else
14666       PlayLevelSoundElementAction(x, y, element, ACTION_PUSHING);
14667
14668     InitMovingField(x, y, move_direction);
14669     GfxAction[x][y] = ACTION_PUSHING;
14670
14671     if (mode == DF_SNAP)
14672       ContinueMoving(x, y);
14673     else
14674       MovPos[x][y] = (dx != 0 ? dx : dy);
14675
14676     Pushed[x][y] = TRUE;
14677     Pushed[nextx][nexty] = TRUE;
14678
14679     if (game.engine_version < VERSION_IDENT(2,2,0,7))
14680       player->push_delay_value = GET_NEW_PUSH_DELAY(element);
14681     else
14682       player->push_delay_value = -1;    // get new value later
14683
14684     // check for element change _after_ element has been pushed
14685     if (game.use_change_when_pushing_bug)
14686     {
14687       CheckElementChangeByPlayer(x, y, element, CE_PUSHED_BY_PLAYER,
14688                                  player->index_bit, dig_side);
14689       CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_PUSHES_X,
14690                                           player->index_bit, dig_side);
14691     }
14692   }
14693   else if (IS_SWITCHABLE(element))
14694   {
14695     if (PLAYER_SWITCHING(player, x, y))
14696     {
14697       CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_PRESSES_X,
14698                                           player->index_bit, dig_side);
14699
14700       return MP_ACTION;
14701     }
14702
14703     player->is_switching = TRUE;
14704     player->switch_x = x;
14705     player->switch_y = y;
14706
14707     PlayLevelSoundElementAction(x, y, element, ACTION_ACTIVATING);
14708
14709     if (element == EL_ROBOT_WHEEL)
14710     {
14711       Tile[x][y] = EL_ROBOT_WHEEL_ACTIVE;
14712
14713       game.robot_wheel_x = x;
14714       game.robot_wheel_y = y;
14715       game.robot_wheel_active = TRUE;
14716
14717       TEST_DrawLevelField(x, y);
14718     }
14719     else if (element == EL_SP_TERMINAL)
14720     {
14721       int xx, yy;
14722
14723       SCAN_PLAYFIELD(xx, yy)
14724       {
14725         if (Tile[xx][yy] == EL_SP_DISK_YELLOW)
14726         {
14727           Bang(xx, yy);
14728         }
14729         else if (Tile[xx][yy] == EL_SP_TERMINAL)
14730         {
14731           Tile[xx][yy] = EL_SP_TERMINAL_ACTIVE;
14732
14733           ResetGfxAnimation(xx, yy);
14734           TEST_DrawLevelField(xx, yy);
14735         }
14736       }
14737     }
14738     else if (IS_BELT_SWITCH(element))
14739     {
14740       ToggleBeltSwitch(x, y);
14741     }
14742     else if (element == EL_SWITCHGATE_SWITCH_UP ||
14743              element == EL_SWITCHGATE_SWITCH_DOWN ||
14744              element == EL_DC_SWITCHGATE_SWITCH_UP ||
14745              element == EL_DC_SWITCHGATE_SWITCH_DOWN)
14746     {
14747       ToggleSwitchgateSwitch();
14748     }
14749     else if (element == EL_LIGHT_SWITCH ||
14750              element == EL_LIGHT_SWITCH_ACTIVE)
14751     {
14752       ToggleLightSwitch(x, y);
14753     }
14754     else if (element == EL_TIMEGATE_SWITCH ||
14755              element == EL_DC_TIMEGATE_SWITCH)
14756     {
14757       ActivateTimegateSwitch(x, y);
14758     }
14759     else if (element == EL_BALLOON_SWITCH_LEFT  ||
14760              element == EL_BALLOON_SWITCH_RIGHT ||
14761              element == EL_BALLOON_SWITCH_UP    ||
14762              element == EL_BALLOON_SWITCH_DOWN  ||
14763              element == EL_BALLOON_SWITCH_NONE  ||
14764              element == EL_BALLOON_SWITCH_ANY)
14765     {
14766       game.wind_direction = (element == EL_BALLOON_SWITCH_LEFT  ? MV_LEFT  :
14767                              element == EL_BALLOON_SWITCH_RIGHT ? MV_RIGHT :
14768                              element == EL_BALLOON_SWITCH_UP    ? MV_UP    :
14769                              element == EL_BALLOON_SWITCH_DOWN  ? MV_DOWN  :
14770                              element == EL_BALLOON_SWITCH_NONE  ? MV_NONE  :
14771                              move_direction);
14772     }
14773     else if (element == EL_LAMP)
14774     {
14775       Tile[x][y] = EL_LAMP_ACTIVE;
14776       game.lights_still_needed--;
14777
14778       ResetGfxAnimation(x, y);
14779       TEST_DrawLevelField(x, y);
14780     }
14781     else if (element == EL_TIME_ORB_FULL)
14782     {
14783       Tile[x][y] = EL_TIME_ORB_EMPTY;
14784
14785       if (level.time > 0 || level.use_time_orb_bug)
14786       {
14787         TimeLeft += level.time_orb_time;
14788         game.no_level_time_limit = FALSE;
14789
14790         game_panel_controls[GAME_PANEL_TIME].value = TimeLeft;
14791
14792         DisplayGameControlValues();
14793       }
14794
14795       ResetGfxAnimation(x, y);
14796       TEST_DrawLevelField(x, y);
14797     }
14798     else if (element == EL_EMC_MAGIC_BALL_SWITCH ||
14799              element == EL_EMC_MAGIC_BALL_SWITCH_ACTIVE)
14800     {
14801       int xx, yy;
14802
14803       game.ball_active = !game.ball_active;
14804
14805       SCAN_PLAYFIELD(xx, yy)
14806       {
14807         int e = Tile[xx][yy];
14808
14809         if (game.ball_active)
14810         {
14811           if (e == EL_EMC_MAGIC_BALL)
14812             CreateField(xx, yy, EL_EMC_MAGIC_BALL_ACTIVE);
14813           else if (e == EL_EMC_MAGIC_BALL_SWITCH)
14814             CreateField(xx, yy, EL_EMC_MAGIC_BALL_SWITCH_ACTIVE);
14815         }
14816         else
14817         {
14818           if (e == EL_EMC_MAGIC_BALL_ACTIVE)
14819             CreateField(xx, yy, EL_EMC_MAGIC_BALL);
14820           else if (e == EL_EMC_MAGIC_BALL_SWITCH_ACTIVE)
14821             CreateField(xx, yy, EL_EMC_MAGIC_BALL_SWITCH);
14822         }
14823       }
14824     }
14825
14826     CheckTriggeredElementChangeByPlayer(x, y, element, CE_SWITCH_OF_X,
14827                                         player->index_bit, dig_side);
14828
14829     CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_SWITCHES_X,
14830                                         player->index_bit, dig_side);
14831
14832     CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_PRESSES_X,
14833                                         player->index_bit, dig_side);
14834
14835     return MP_ACTION;
14836   }
14837   else
14838   {
14839     if (!PLAYER_SWITCHING(player, x, y))
14840     {
14841       player->is_switching = TRUE;
14842       player->switch_x = x;
14843       player->switch_y = y;
14844
14845       CheckElementChangeByPlayer(x, y, element, CE_SWITCHED,
14846                                  player->index_bit, dig_side);
14847       CheckTriggeredElementChangeByPlayer(x, y, element, CE_SWITCH_OF_X,
14848                                           player->index_bit, dig_side);
14849
14850       CheckElementChangeByPlayer(x, y, element, CE_SWITCHED_BY_PLAYER,
14851                                  player->index_bit, dig_side);
14852       CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_SWITCHES_X,
14853                                           player->index_bit, dig_side);
14854     }
14855
14856     CheckElementChangeByPlayer(x, y, element, CE_PRESSED_BY_PLAYER,
14857                                player->index_bit, dig_side);
14858     CheckTriggeredElementChangeByPlayer(x, y, element, CE_PLAYER_PRESSES_X,
14859                                         player->index_bit, dig_side);
14860
14861     return MP_NO_ACTION;
14862   }
14863
14864   player->push_delay = -1;
14865
14866   if (is_player)                // function can also be called by EL_PENGUIN
14867   {
14868     if (Tile[x][y] != element)          // really digged/collected something
14869     {
14870       player->is_collecting = !player->is_digging;
14871       player->is_active = TRUE;
14872
14873       player->last_removed_element = element;
14874     }
14875   }
14876
14877   return MP_MOVING;
14878 }
14879
14880 static boolean DigFieldByCE(int x, int y, int digging_element)
14881 {
14882   int element = Tile[x][y];
14883
14884   if (!IS_FREE(x, y))
14885   {
14886     int action = (IS_DIGGABLE(element) ? ACTION_DIGGING :
14887                   IS_COLLECTIBLE(element) ? ACTION_COLLECTING :
14888                   ACTION_BREAKING);
14889
14890     // no element can dig solid indestructible elements
14891     if (IS_INDESTRUCTIBLE(element) &&
14892         !IS_DIGGABLE(element) &&
14893         !IS_COLLECTIBLE(element))
14894       return FALSE;
14895
14896     if (AmoebaNr[x][y] &&
14897         (element == EL_AMOEBA_FULL ||
14898          element == EL_BD_AMOEBA ||
14899          element == EL_AMOEBA_GROWING))
14900     {
14901       AmoebaCnt[AmoebaNr[x][y]]--;
14902       AmoebaCnt2[AmoebaNr[x][y]]--;
14903     }
14904
14905     if (IS_MOVING(x, y))
14906       RemoveMovingField(x, y);
14907     else
14908     {
14909       RemoveField(x, y);
14910       TEST_DrawLevelField(x, y);
14911     }
14912
14913     // if digged element was about to explode, prevent the explosion
14914     ExplodeField[x][y] = EX_TYPE_NONE;
14915
14916     PlayLevelSoundAction(x, y, action);
14917   }
14918
14919   Store[x][y] = EL_EMPTY;
14920
14921   // this makes it possible to leave the removed element again
14922   if (IS_EQUAL_OR_IN_GROUP(element, MOVE_ENTER_EL(digging_element)))
14923     Store[x][y] = element;
14924
14925   return TRUE;
14926 }
14927
14928 static boolean SnapField(struct PlayerInfo *player, int dx, int dy)
14929 {
14930   int jx = player->jx, jy = player->jy;
14931   int x = jx + dx, y = jy + dy;
14932   int snap_direction = (dx == -1 ? MV_LEFT  :
14933                         dx == +1 ? MV_RIGHT :
14934                         dy == -1 ? MV_UP    :
14935                         dy == +1 ? MV_DOWN  : MV_NONE);
14936   boolean can_continue_snapping = (level.continuous_snapping &&
14937                                    WasJustFalling[x][y] < CHECK_DELAY_FALLING);
14938
14939   if (player->MovPos != 0 && game.engine_version >= VERSION_IDENT(2,2,0,0))
14940     return FALSE;
14941
14942   if (!player->active || !IN_LEV_FIELD(x, y))
14943     return FALSE;
14944
14945   if (dx && dy)
14946     return FALSE;
14947
14948   if (!dx && !dy)
14949   {
14950     if (player->MovPos == 0)
14951       player->is_pushing = FALSE;
14952
14953     player->is_snapping = FALSE;
14954
14955     if (player->MovPos == 0)
14956     {
14957       player->is_moving = FALSE;
14958       player->is_digging = FALSE;
14959       player->is_collecting = FALSE;
14960     }
14961
14962     return FALSE;
14963   }
14964
14965   // prevent snapping with already pressed snap key when not allowed
14966   if (player->is_snapping && !can_continue_snapping)
14967     return FALSE;
14968
14969   player->MovDir = snap_direction;
14970
14971   if (player->MovPos == 0)
14972   {
14973     player->is_moving = FALSE;
14974     player->is_digging = FALSE;
14975     player->is_collecting = FALSE;
14976   }
14977
14978   player->is_dropping = FALSE;
14979   player->is_dropping_pressed = FALSE;
14980   player->drop_pressed_delay = 0;
14981
14982   if (DigField(player, jx, jy, x, y, 0, 0, DF_SNAP) == MP_NO_ACTION)
14983     return FALSE;
14984
14985   player->is_snapping = TRUE;
14986   player->is_active = TRUE;
14987
14988   if (player->MovPos == 0)
14989   {
14990     player->is_moving = FALSE;
14991     player->is_digging = FALSE;
14992     player->is_collecting = FALSE;
14993   }
14994
14995   if (player->MovPos != 0)      // prevent graphic bugs in versions < 2.2.0
14996     TEST_DrawLevelField(player->last_jx, player->last_jy);
14997
14998   TEST_DrawLevelField(x, y);
14999
15000   return TRUE;
15001 }
15002
15003 static boolean DropElement(struct PlayerInfo *player)
15004 {
15005   int old_element, new_element;
15006   int dropx = player->jx, dropy = player->jy;
15007   int drop_direction = player->MovDir;
15008   int drop_side = drop_direction;
15009   int drop_element = get_next_dropped_element(player);
15010
15011   /* do not drop an element on top of another element; when holding drop key
15012      pressed without moving, dropped element must move away before the next
15013      element can be dropped (this is especially important if the next element
15014      is dynamite, which can be placed on background for historical reasons) */
15015   if (PLAYER_DROPPING(player, dropx, dropy) && Tile[dropx][dropy] != EL_EMPTY)
15016     return MP_ACTION;
15017
15018   if (IS_THROWABLE(drop_element))
15019   {
15020     dropx += GET_DX_FROM_DIR(drop_direction);
15021     dropy += GET_DY_FROM_DIR(drop_direction);
15022
15023     if (!IN_LEV_FIELD(dropx, dropy))
15024       return FALSE;
15025   }
15026
15027   old_element = Tile[dropx][dropy];     // old element at dropping position
15028   new_element = drop_element;           // default: no change when dropping
15029
15030   // check if player is active, not moving and ready to drop
15031   if (!player->active || player->MovPos || player->drop_delay > 0)
15032     return FALSE;
15033
15034   // check if player has anything that can be dropped
15035   if (new_element == EL_UNDEFINED)
15036     return FALSE;
15037
15038   // only set if player has anything that can be dropped
15039   player->is_dropping_pressed = TRUE;
15040
15041   // check if drop key was pressed long enough for EM style dynamite
15042   if (new_element == EL_EM_DYNAMITE && player->drop_pressed_delay < 40)
15043     return FALSE;
15044
15045   // check if anything can be dropped at the current position
15046   if (IS_ACTIVE_BOMB(old_element) || old_element == EL_EXPLOSION)
15047     return FALSE;
15048
15049   // collected custom elements can only be dropped on empty fields
15050   if (IS_CUSTOM_ELEMENT(new_element) && old_element != EL_EMPTY)
15051     return FALSE;
15052
15053   if (old_element != EL_EMPTY)
15054     Back[dropx][dropy] = old_element;   // store old element on this field
15055
15056   ResetGfxAnimation(dropx, dropy);
15057   ResetRandomAnimationValue(dropx, dropy);
15058
15059   if (player->inventory_size > 0 ||
15060       player->inventory_infinite_element != EL_UNDEFINED)
15061   {
15062     if (player->inventory_size > 0)
15063     {
15064       player->inventory_size--;
15065
15066       DrawGameDoorValues();
15067
15068       if (new_element == EL_DYNAMITE)
15069         new_element = EL_DYNAMITE_ACTIVE;
15070       else if (new_element == EL_EM_DYNAMITE)
15071         new_element = EL_EM_DYNAMITE_ACTIVE;
15072       else if (new_element == EL_SP_DISK_RED)
15073         new_element = EL_SP_DISK_RED_ACTIVE;
15074     }
15075
15076     Tile[dropx][dropy] = new_element;
15077
15078     if (IN_SCR_FIELD(SCREENX(dropx), SCREENY(dropy)))
15079       DrawGraphicThruMask(SCREENX(dropx), SCREENY(dropy),
15080                           el2img(Tile[dropx][dropy]), 0);
15081
15082     PlayLevelSoundAction(dropx, dropy, ACTION_DROPPING);
15083
15084     // needed if previous element just changed to "empty" in the last frame
15085     ChangeCount[dropx][dropy] = 0;      // allow at least one more change
15086
15087     CheckElementChangeByPlayer(dropx, dropy, new_element, CE_DROPPED_BY_PLAYER,
15088                                player->index_bit, drop_side);
15089     CheckTriggeredElementChangeByPlayer(dropx, dropy, new_element,
15090                                         CE_PLAYER_DROPS_X,
15091                                         player->index_bit, drop_side);
15092
15093     TestIfElementTouchesCustomElement(dropx, dropy);
15094   }
15095   else          // player is dropping a dyna bomb
15096   {
15097     player->dynabombs_left--;
15098
15099     Tile[dropx][dropy] = new_element;
15100
15101     if (IN_SCR_FIELD(SCREENX(dropx), SCREENY(dropy)))
15102       DrawGraphicThruMask(SCREENX(dropx), SCREENY(dropy),
15103                           el2img(Tile[dropx][dropy]), 0);
15104
15105     PlayLevelSoundAction(dropx, dropy, ACTION_DROPPING);
15106   }
15107
15108   if (Tile[dropx][dropy] == new_element) // uninitialized unless CE change
15109     InitField_WithBug1(dropx, dropy, FALSE);
15110
15111   new_element = Tile[dropx][dropy];     // element might have changed
15112
15113   if (IS_CUSTOM_ELEMENT(new_element) && CAN_MOVE(new_element) &&
15114       element_info[new_element].move_pattern == MV_WHEN_DROPPED)
15115   {
15116     if (element_info[new_element].move_direction_initial == MV_START_AUTOMATIC)
15117       MovDir[dropx][dropy] = drop_direction;
15118
15119     ChangeCount[dropx][dropy] = 0;      // allow at least one more change
15120
15121     // do not cause impact style collision by dropping elements that can fall
15122     CheckCollision[dropx][dropy] = CHECK_DELAY_COLLISION;
15123   }
15124
15125   player->drop_delay = GET_NEW_DROP_DELAY(drop_element);
15126   player->is_dropping = TRUE;
15127
15128   player->drop_pressed_delay = 0;
15129   player->is_dropping_pressed = FALSE;
15130
15131   player->drop_x = dropx;
15132   player->drop_y = dropy;
15133
15134   return TRUE;
15135 }
15136
15137 // ----------------------------------------------------------------------------
15138 // game sound playing functions
15139 // ----------------------------------------------------------------------------
15140
15141 static int *loop_sound_frame = NULL;
15142 static int *loop_sound_volume = NULL;
15143
15144 void InitPlayLevelSound(void)
15145 {
15146   int num_sounds = getSoundListSize();
15147
15148   checked_free(loop_sound_frame);
15149   checked_free(loop_sound_volume);
15150
15151   loop_sound_frame  = checked_calloc(num_sounds * sizeof(int));
15152   loop_sound_volume = checked_calloc(num_sounds * sizeof(int));
15153 }
15154
15155 static void PlayLevelSound(int x, int y, int nr)
15156 {
15157   int sx = SCREENX(x), sy = SCREENY(y);
15158   int volume, stereo_position;
15159   int max_distance = 8;
15160   int type = (IS_LOOP_SOUND(nr) ? SND_CTRL_PLAY_LOOP : SND_CTRL_PLAY_SOUND);
15161
15162   if ((!setup.sound_simple && !IS_LOOP_SOUND(nr)) ||
15163       (!setup.sound_loops && IS_LOOP_SOUND(nr)))
15164     return;
15165
15166   if (!IN_LEV_FIELD(x, y) ||
15167       sx < -max_distance || sx >= SCR_FIELDX + max_distance ||
15168       sy < -max_distance || sy >= SCR_FIELDY + max_distance)
15169     return;
15170
15171   volume = SOUND_MAX_VOLUME;
15172
15173   if (!IN_SCR_FIELD(sx, sy))
15174   {
15175     int dx = ABS(sx - SCR_FIELDX / 2) - SCR_FIELDX / 2;
15176     int dy = ABS(sy - SCR_FIELDY / 2) - SCR_FIELDY / 2;
15177
15178     volume -= volume * (dx > dy ? dx : dy) / max_distance;
15179   }
15180
15181   stereo_position = (SOUND_MAX_LEFT +
15182                      (sx + max_distance) * SOUND_MAX_LEFT2RIGHT /
15183                      (SCR_FIELDX + 2 * max_distance));
15184
15185   if (IS_LOOP_SOUND(nr))
15186   {
15187     /* This assures that quieter loop sounds do not overwrite louder ones,
15188        while restarting sound volume comparison with each new game frame. */
15189
15190     if (loop_sound_volume[nr] > volume && loop_sound_frame[nr] == FrameCounter)
15191       return;
15192
15193     loop_sound_volume[nr] = volume;
15194     loop_sound_frame[nr] = FrameCounter;
15195   }
15196
15197   PlaySoundExt(nr, volume, stereo_position, type);
15198 }
15199
15200 static void PlayLevelSoundNearest(int x, int y, int sound_action)
15201 {
15202   PlayLevelSound(x < LEVELX(BX1) ? LEVELX(BX1) :
15203                  x > LEVELX(BX2) ? LEVELX(BX2) : x,
15204                  y < LEVELY(BY1) ? LEVELY(BY1) :
15205                  y > LEVELY(BY2) ? LEVELY(BY2) : y,
15206                  sound_action);
15207 }
15208
15209 static void PlayLevelSoundAction(int x, int y, int action)
15210 {
15211   PlayLevelSoundElementAction(x, y, Tile[x][y], action);
15212 }
15213
15214 static void PlayLevelSoundElementAction(int x, int y, int element, int action)
15215 {
15216   int sound_effect = element_info[SND_ELEMENT(element)].sound[action];
15217
15218   if (sound_effect != SND_UNDEFINED)
15219     PlayLevelSound(x, y, sound_effect);
15220 }
15221
15222 static void PlayLevelSoundElementActionIfLoop(int x, int y, int element,
15223                                               int action)
15224 {
15225   int sound_effect = element_info[SND_ELEMENT(element)].sound[action];
15226
15227   if (sound_effect != SND_UNDEFINED && IS_LOOP_SOUND(sound_effect))
15228     PlayLevelSound(x, y, sound_effect);
15229 }
15230
15231 static void PlayLevelSoundActionIfLoop(int x, int y, int action)
15232 {
15233   int sound_effect = element_info[SND_ELEMENT(Tile[x][y])].sound[action];
15234
15235   if (sound_effect != SND_UNDEFINED && IS_LOOP_SOUND(sound_effect))
15236     PlayLevelSound(x, y, sound_effect);
15237 }
15238
15239 static void StopLevelSoundActionIfLoop(int x, int y, int action)
15240 {
15241   int sound_effect = element_info[SND_ELEMENT(Tile[x][y])].sound[action];
15242
15243   if (sound_effect != SND_UNDEFINED && IS_LOOP_SOUND(sound_effect))
15244     StopSound(sound_effect);
15245 }
15246
15247 static int getLevelMusicNr(void)
15248 {
15249   int level_pos = level_nr - leveldir_current->first_level;
15250
15251   if (levelset.music[level_nr] != MUS_UNDEFINED)
15252     return levelset.music[level_nr];            // from config file
15253   else
15254     return MAP_NOCONF_MUSIC(level_pos);         // from music dir
15255 }
15256
15257 static void FadeLevelSounds(void)
15258 {
15259   FadeSounds();
15260 }
15261
15262 static void FadeLevelMusic(void)
15263 {
15264   int music_nr = getLevelMusicNr();
15265   char *curr_music = getCurrentlyPlayingMusicFilename();
15266   char *next_music = getMusicInfoEntryFilename(music_nr);
15267
15268   if (!strEqual(curr_music, next_music))
15269     FadeMusic();
15270 }
15271
15272 void FadeLevelSoundsAndMusic(void)
15273 {
15274   FadeLevelSounds();
15275   FadeLevelMusic();
15276 }
15277
15278 static void PlayLevelMusic(void)
15279 {
15280   int music_nr = getLevelMusicNr();
15281   char *curr_music = getCurrentlyPlayingMusicFilename();
15282   char *next_music = getMusicInfoEntryFilename(music_nr);
15283
15284   if (!strEqual(curr_music, next_music))
15285     PlayMusicLoop(music_nr);
15286 }
15287
15288 void PlayLevelSound_EM(int xx, int yy, int element_em, int sample)
15289 {
15290   int element = (element_em > -1 ? map_element_EM_to_RND_game(element_em) : 0);
15291   int offset = 0;
15292   int x = xx - offset;
15293   int y = yy - offset;
15294
15295   switch (sample)
15296   {
15297     case SOUND_blank:
15298       PlayLevelSoundElementAction(x, y, element, ACTION_WALKING);
15299       break;
15300
15301     case SOUND_roll:
15302       PlayLevelSoundElementAction(x, y, element, ACTION_PUSHING);
15303       break;
15304
15305     case SOUND_stone:
15306       PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
15307       break;
15308
15309     case SOUND_nut:
15310       PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
15311       break;
15312
15313     case SOUND_crack:
15314       PlayLevelSoundElementAction(x, y, element, ACTION_BREAKING);
15315       break;
15316
15317     case SOUND_bug:
15318       PlayLevelSoundElementAction(x, y, element, ACTION_MOVING);
15319       break;
15320
15321     case SOUND_tank:
15322       PlayLevelSoundElementAction(x, y, element, ACTION_MOVING);
15323       break;
15324
15325     case SOUND_android_clone:
15326       PlayLevelSoundElementAction(x, y, element, ACTION_DROPPING);
15327       break;
15328
15329     case SOUND_android_move:
15330       PlayLevelSoundElementAction(x, y, element, ACTION_MOVING);
15331       break;
15332
15333     case SOUND_spring:
15334       PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
15335       break;
15336
15337     case SOUND_slurp:
15338       PlayLevelSoundElementAction(x, y, element, ACTION_EATING);
15339       break;
15340
15341     case SOUND_eater:
15342       PlayLevelSoundElementAction(x, y, element, ACTION_WAITING);
15343       break;
15344
15345     case SOUND_eater_eat:
15346       PlayLevelSoundElementAction(x, y, element, ACTION_DIGGING);
15347       break;
15348
15349     case SOUND_alien:
15350       PlayLevelSoundElementAction(x, y, element, ACTION_MOVING);
15351       break;
15352
15353     case SOUND_collect:
15354       PlayLevelSoundElementAction(x, y, element, ACTION_COLLECTING);
15355       break;
15356
15357     case SOUND_diamond:
15358       PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
15359       break;
15360
15361     case SOUND_squash:
15362       // !!! CHECK THIS !!!
15363 #if 1
15364       PlayLevelSoundElementAction(x, y, element, ACTION_BREAKING);
15365 #else
15366       PlayLevelSoundElementAction(x, y, element, ACTION_SMASHED_BY_ROCK);
15367 #endif
15368       break;
15369
15370     case SOUND_wonderfall:
15371       PlayLevelSoundElementAction(x, y, element, ACTION_FILLING);
15372       break;
15373
15374     case SOUND_drip:
15375       PlayLevelSoundElementAction(x, y, element, ACTION_IMPACT);
15376       break;
15377
15378     case SOUND_push:
15379       PlayLevelSoundElementAction(x, y, element, ACTION_PUSHING);
15380       break;
15381
15382     case SOUND_dirt:
15383       PlayLevelSoundElementAction(x, y, element, ACTION_DIGGING);
15384       break;
15385
15386     case SOUND_acid:
15387       PlayLevelSoundElementAction(x, y, element, ACTION_SPLASHING);
15388       break;
15389
15390     case SOUND_ball:
15391       PlayLevelSoundElementAction(x, y, element, ACTION_DROPPING);
15392       break;
15393
15394     case SOUND_slide:
15395       PlayLevelSoundElementAction(x, y, element, ACTION_GROWING);
15396       break;
15397
15398     case SOUND_wonder:
15399       PlayLevelSoundElementAction(x, y, element, ACTION_ACTIVE);
15400       break;
15401
15402     case SOUND_door:
15403       PlayLevelSoundElementAction(x, y, element, ACTION_PASSING);
15404       break;
15405
15406     case SOUND_exit_open:
15407       PlayLevelSoundElementAction(x, y, element, ACTION_OPENING);
15408       break;
15409
15410     case SOUND_exit_leave:
15411       PlayLevelSoundElementAction(x, y, element, ACTION_PASSING);
15412       break;
15413
15414     case SOUND_dynamite:
15415       PlayLevelSoundElementAction(x, y, element, ACTION_DROPPING);
15416       break;
15417
15418     case SOUND_tick:
15419       PlayLevelSoundElementAction(x, y, element, ACTION_ACTIVE);
15420       break;
15421
15422     case SOUND_press:
15423       PlayLevelSoundElementAction(x, y, element, ACTION_ACTIVATING);
15424       break;
15425
15426     case SOUND_wheel:
15427       PlayLevelSoundElementAction(x, y, element, ACTION_ACTIVE);
15428       break;
15429
15430     case SOUND_boom:
15431       PlayLevelSoundElementAction(x, y, element, ACTION_EXPLODING);
15432       break;
15433
15434     case SOUND_die:
15435       PlayLevelSoundElementAction(x, y, element, ACTION_DYING);
15436       break;
15437
15438     case SOUND_time:
15439       PlaySound(SND_GAME_RUNNING_OUT_OF_TIME);
15440       break;
15441
15442     default:
15443       PlayLevelSoundElementAction(x, y, element, ACTION_DEFAULT);
15444       break;
15445   }
15446 }
15447
15448 void PlayLevelSound_SP(int xx, int yy, int element_sp, int action_sp)
15449 {
15450   int element = map_element_SP_to_RND(element_sp);
15451   int action = map_action_SP_to_RND(action_sp);
15452   int offset = (setup.sp_show_border_elements ? 0 : 1);
15453   int x = xx - offset;
15454   int y = yy - offset;
15455
15456   PlayLevelSoundElementAction(x, y, element, action);
15457 }
15458
15459 void PlayLevelSound_MM(int xx, int yy, int element_mm, int action_mm)
15460 {
15461   int element = map_element_MM_to_RND(element_mm);
15462   int action = map_action_MM_to_RND(action_mm);
15463   int offset = 0;
15464   int x = xx - offset;
15465   int y = yy - offset;
15466
15467   if (!IS_MM_ELEMENT(element))
15468     element = EL_MM_DEFAULT;
15469
15470   PlayLevelSoundElementAction(x, y, element, action);
15471 }
15472
15473 void PlaySound_MM(int sound_mm)
15474 {
15475   int sound = map_sound_MM_to_RND(sound_mm);
15476
15477   if (sound == SND_UNDEFINED)
15478     return;
15479
15480   PlaySound(sound);
15481 }
15482
15483 void PlaySoundLoop_MM(int sound_mm)
15484 {
15485   int sound = map_sound_MM_to_RND(sound_mm);
15486
15487   if (sound == SND_UNDEFINED)
15488     return;
15489
15490   PlaySoundLoop(sound);
15491 }
15492
15493 void StopSound_MM(int sound_mm)
15494 {
15495   int sound = map_sound_MM_to_RND(sound_mm);
15496
15497   if (sound == SND_UNDEFINED)
15498     return;
15499
15500   StopSound(sound);
15501 }
15502
15503 void RaiseScore(int value)
15504 {
15505   game.score += value;
15506
15507   game_panel_controls[GAME_PANEL_SCORE].value = game.score;
15508
15509   DisplayGameControlValues();
15510 }
15511
15512 void RaiseScoreElement(int element)
15513 {
15514   switch (element)
15515   {
15516     case EL_EMERALD:
15517     case EL_BD_DIAMOND:
15518     case EL_EMERALD_YELLOW:
15519     case EL_EMERALD_RED:
15520     case EL_EMERALD_PURPLE:
15521     case EL_SP_INFOTRON:
15522       RaiseScore(level.score[SC_EMERALD]);
15523       break;
15524     case EL_DIAMOND:
15525       RaiseScore(level.score[SC_DIAMOND]);
15526       break;
15527     case EL_CRYSTAL:
15528       RaiseScore(level.score[SC_CRYSTAL]);
15529       break;
15530     case EL_PEARL:
15531       RaiseScore(level.score[SC_PEARL]);
15532       break;
15533     case EL_BUG:
15534     case EL_BD_BUTTERFLY:
15535     case EL_SP_ELECTRON:
15536       RaiseScore(level.score[SC_BUG]);
15537       break;
15538     case EL_SPACESHIP:
15539     case EL_BD_FIREFLY:
15540     case EL_SP_SNIKSNAK:
15541       RaiseScore(level.score[SC_SPACESHIP]);
15542       break;
15543     case EL_YAMYAM:
15544     case EL_DARK_YAMYAM:
15545       RaiseScore(level.score[SC_YAMYAM]);
15546       break;
15547     case EL_ROBOT:
15548       RaiseScore(level.score[SC_ROBOT]);
15549       break;
15550     case EL_PACMAN:
15551       RaiseScore(level.score[SC_PACMAN]);
15552       break;
15553     case EL_NUT:
15554       RaiseScore(level.score[SC_NUT]);
15555       break;
15556     case EL_DYNAMITE:
15557     case EL_EM_DYNAMITE:
15558     case EL_SP_DISK_RED:
15559     case EL_DYNABOMB_INCREASE_NUMBER:
15560     case EL_DYNABOMB_INCREASE_SIZE:
15561     case EL_DYNABOMB_INCREASE_POWER:
15562       RaiseScore(level.score[SC_DYNAMITE]);
15563       break;
15564     case EL_SHIELD_NORMAL:
15565     case EL_SHIELD_DEADLY:
15566       RaiseScore(level.score[SC_SHIELD]);
15567       break;
15568     case EL_EXTRA_TIME:
15569       RaiseScore(level.extra_time_score);
15570       break;
15571     case EL_KEY_1:
15572     case EL_KEY_2:
15573     case EL_KEY_3:
15574     case EL_KEY_4:
15575     case EL_EM_KEY_1:
15576     case EL_EM_KEY_2:
15577     case EL_EM_KEY_3:
15578     case EL_EM_KEY_4:
15579     case EL_EMC_KEY_5:
15580     case EL_EMC_KEY_6:
15581     case EL_EMC_KEY_7:
15582     case EL_EMC_KEY_8:
15583     case EL_DC_KEY_WHITE:
15584       RaiseScore(level.score[SC_KEY]);
15585       break;
15586     default:
15587       RaiseScore(element_info[element].collect_score);
15588       break;
15589   }
15590 }
15591
15592 void RequestQuitGameExt(boolean skip_request, boolean quick_quit, char *message)
15593 {
15594   if (skip_request || Request(message, REQ_ASK | REQ_STAY_CLOSED))
15595   {
15596     if (!quick_quit)
15597     {
15598       // prevent short reactivation of overlay buttons while closing door
15599       SetOverlayActive(FALSE);
15600       UnmapGameButtons();
15601
15602       // door may still be open due to skipped or envelope style request
15603       CloseDoor(score_info_tape_play ? DOOR_CLOSE_ALL : DOOR_CLOSE_1);
15604     }
15605
15606     if (network.enabled)
15607       SendToServer_StopPlaying(NETWORK_STOP_BY_PLAYER);
15608     else
15609     {
15610       if (quick_quit)
15611         FadeSkipNextFadeIn();
15612
15613       SetGameStatus(GAME_MODE_MAIN);
15614
15615       DrawMainMenu();
15616     }
15617   }
15618   else          // continue playing the game
15619   {
15620     if (tape.playing && tape.deactivate_display)
15621       TapeDeactivateDisplayOff(TRUE);
15622
15623     OpenDoor(DOOR_OPEN_1 | DOOR_COPY_BACK);
15624
15625     if (tape.playing && tape.deactivate_display)
15626       TapeDeactivateDisplayOn();
15627   }
15628 }
15629
15630 void RequestQuitGame(boolean escape_key_pressed)
15631 {
15632   boolean ask_on_escape = (setup.ask_on_escape && setup.ask_on_quit_game);
15633   boolean quick_quit = ((escape_key_pressed && !ask_on_escape) ||
15634                         level_editor_test_game);
15635   boolean skip_request = (game.all_players_gone || !setup.ask_on_quit_game ||
15636                           quick_quit || score_info_tape_play);
15637
15638   RequestQuitGameExt(skip_request, quick_quit,
15639                      "Do you really want to quit the game?");
15640 }
15641
15642 static char *getRestartGameMessage(void)
15643 {
15644   boolean play_again = hasStartedNetworkGame();
15645   static char message[MAX_OUTPUT_LINESIZE];
15646   char *game_over_text = "Game over!";
15647   char *play_again_text = " Play it again?";
15648
15649   if (level.game_engine_type == GAME_ENGINE_TYPE_MM &&
15650       game_mm.game_over_message != NULL)
15651     game_over_text = game_mm.game_over_message;
15652
15653   snprintf(message, MAX_OUTPUT_LINESIZE, "%s%s", game_over_text,
15654            (play_again ? play_again_text : ""));
15655
15656   return message;
15657 }
15658
15659 static void RequestRestartGame(void)
15660 {
15661   char *message = getRestartGameMessage();
15662   boolean has_started_game = hasStartedNetworkGame();
15663   int request_mode = (has_started_game ? REQ_ASK : REQ_CONFIRM);
15664   int door_state = DOOR_CLOSE_1;
15665
15666   if (Request(message, request_mode | REQ_STAY_OPEN) && has_started_game)
15667   {
15668     CloseDoor(door_state);
15669
15670     StartGameActions(network.enabled, setup.autorecord, level.random_seed);
15671   }
15672   else
15673   {
15674     // if game was invoked from level editor, also close tape recorder door
15675     if (level_editor_test_game)
15676       door_state = DOOR_CLOSE_ALL;
15677
15678     CloseDoor(door_state);
15679
15680     SetGameStatus(GAME_MODE_MAIN);
15681
15682     DrawMainMenu();
15683   }
15684 }
15685
15686 boolean CheckRestartGame(void)
15687 {
15688   static int game_over_delay = 0;
15689   int game_over_delay_value = 50;
15690   boolean game_over = checkGameFailed();
15691
15692   if (!game_over)
15693   {
15694     game_over_delay = game_over_delay_value;
15695
15696     return FALSE;
15697   }
15698
15699   if (game_over_delay > 0)
15700   {
15701     if (game_over_delay == game_over_delay_value / 2)
15702       PlaySound(SND_GAME_LOSING);
15703
15704     game_over_delay--;
15705
15706     return FALSE;
15707   }
15708
15709   // do not handle game over if request dialog is already active
15710   if (game.request_active)
15711     return FALSE;
15712
15713   // do not ask to play again if game was never actually played
15714   if (!game.GamePlayed)
15715     return FALSE;
15716
15717   // do not ask to play again if this was disabled in setup menu
15718   if (!setup.ask_on_game_over)
15719     return FALSE;
15720
15721   RequestRestartGame();
15722
15723   return TRUE;
15724 }
15725
15726 boolean checkGameSolved(void)
15727 {
15728   // set for all game engines if level was solved
15729   return game.LevelSolved_GameEnd;
15730 }
15731
15732 boolean checkGameFailed(void)
15733 {
15734   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
15735     return (game_em.game_over && !game_em.level_solved);
15736   else if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
15737     return (game_sp.game_over && !game_sp.level_solved);
15738   else if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
15739     return (game_mm.game_over && !game_mm.level_solved);
15740   else                          // GAME_ENGINE_TYPE_RND
15741     return (game.GameOver && !game.LevelSolved);
15742 }
15743
15744 boolean checkGameEnded(void)
15745 {
15746   return (checkGameSolved() || checkGameFailed());
15747 }
15748
15749
15750 // ----------------------------------------------------------------------------
15751 // random generator functions
15752 // ----------------------------------------------------------------------------
15753
15754 unsigned int InitEngineRandom_RND(int seed)
15755 {
15756   game.num_random_calls = 0;
15757
15758   return InitEngineRandom(seed);
15759 }
15760
15761 unsigned int RND(int max)
15762 {
15763   if (max > 0)
15764   {
15765     game.num_random_calls++;
15766
15767     return GetEngineRandom(max);
15768   }
15769
15770   return 0;
15771 }
15772
15773
15774 // ----------------------------------------------------------------------------
15775 // game engine snapshot handling functions
15776 // ----------------------------------------------------------------------------
15777
15778 struct EngineSnapshotInfo
15779 {
15780   // runtime values for custom element collect score
15781   int collect_score[NUM_CUSTOM_ELEMENTS];
15782
15783   // runtime values for group element choice position
15784   int choice_pos[NUM_GROUP_ELEMENTS];
15785
15786   // runtime values for belt position animations
15787   int belt_graphic[4][NUM_BELT_PARTS];
15788   int belt_anim_mode[4][NUM_BELT_PARTS];
15789 };
15790
15791 static struct EngineSnapshotInfo engine_snapshot_rnd;
15792 static char *snapshot_level_identifier = NULL;
15793 static int snapshot_level_nr = -1;
15794
15795 static void SaveEngineSnapshotValues_RND(void)
15796 {
15797   static int belt_base_active_element[4] =
15798   {
15799     EL_CONVEYOR_BELT_1_LEFT_ACTIVE,
15800     EL_CONVEYOR_BELT_2_LEFT_ACTIVE,
15801     EL_CONVEYOR_BELT_3_LEFT_ACTIVE,
15802     EL_CONVEYOR_BELT_4_LEFT_ACTIVE
15803   };
15804   int i, j;
15805
15806   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
15807   {
15808     int element = EL_CUSTOM_START + i;
15809
15810     engine_snapshot_rnd.collect_score[i] = element_info[element].collect_score;
15811   }
15812
15813   for (i = 0; i < NUM_GROUP_ELEMENTS; i++)
15814   {
15815     int element = EL_GROUP_START + i;
15816
15817     engine_snapshot_rnd.choice_pos[i] = element_info[element].group->choice_pos;
15818   }
15819
15820   for (i = 0; i < 4; i++)
15821   {
15822     for (j = 0; j < NUM_BELT_PARTS; j++)
15823     {
15824       int element = belt_base_active_element[i] + j;
15825       int graphic = el2img(element);
15826       int anim_mode = graphic_info[graphic].anim_mode;
15827
15828       engine_snapshot_rnd.belt_graphic[i][j] = graphic;
15829       engine_snapshot_rnd.belt_anim_mode[i][j] = anim_mode;
15830     }
15831   }
15832 }
15833
15834 static void LoadEngineSnapshotValues_RND(void)
15835 {
15836   unsigned int num_random_calls = game.num_random_calls;
15837   int i, j;
15838
15839   for (i = 0; i < NUM_CUSTOM_ELEMENTS; i++)
15840   {
15841     int element = EL_CUSTOM_START + i;
15842
15843     element_info[element].collect_score = engine_snapshot_rnd.collect_score[i];
15844   }
15845
15846   for (i = 0; i < NUM_GROUP_ELEMENTS; i++)
15847   {
15848     int element = EL_GROUP_START + i;
15849
15850     element_info[element].group->choice_pos = engine_snapshot_rnd.choice_pos[i];
15851   }
15852
15853   for (i = 0; i < 4; i++)
15854   {
15855     for (j = 0; j < NUM_BELT_PARTS; j++)
15856     {
15857       int graphic = engine_snapshot_rnd.belt_graphic[i][j];
15858       int anim_mode = engine_snapshot_rnd.belt_anim_mode[i][j];
15859
15860       graphic_info[graphic].anim_mode = anim_mode;
15861     }
15862   }
15863
15864   if (level.game_engine_type == GAME_ENGINE_TYPE_RND)
15865   {
15866     InitRND(tape.random_seed);
15867     for (i = 0; i < num_random_calls; i++)
15868       RND(1);
15869   }
15870
15871   if (game.num_random_calls != num_random_calls)
15872   {
15873     Error("number of random calls out of sync");
15874     Error("number of random calls should be %d", num_random_calls);
15875     Error("number of random calls is %d", game.num_random_calls);
15876
15877     Fail("this should not happen -- please debug");
15878   }
15879 }
15880
15881 void FreeEngineSnapshotSingle(void)
15882 {
15883   FreeSnapshotSingle();
15884
15885   setString(&snapshot_level_identifier, NULL);
15886   snapshot_level_nr = -1;
15887 }
15888
15889 void FreeEngineSnapshotList(void)
15890 {
15891   FreeSnapshotList();
15892 }
15893
15894 static ListNode *SaveEngineSnapshotBuffers(void)
15895 {
15896   ListNode *buffers = NULL;
15897
15898   // copy some special values to a structure better suited for the snapshot
15899
15900   if (level.game_engine_type == GAME_ENGINE_TYPE_RND)
15901     SaveEngineSnapshotValues_RND();
15902   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
15903     SaveEngineSnapshotValues_EM();
15904   if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
15905     SaveEngineSnapshotValues_SP(&buffers);
15906   if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
15907     SaveEngineSnapshotValues_MM();
15908
15909   // save values stored in special snapshot structure
15910
15911   if (level.game_engine_type == GAME_ENGINE_TYPE_RND)
15912     SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(engine_snapshot_rnd));
15913   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
15914     SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(engine_snapshot_em));
15915   if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
15916     SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(engine_snapshot_sp));
15917   if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
15918     SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(engine_snapshot_mm));
15919
15920   // save further RND engine values
15921
15922   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(stored_player));
15923   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(game));
15924   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(tape));
15925
15926   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(FrameCounter));
15927   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(TimeFrames));
15928   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(TimePlayed));
15929   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(TimeLeft));
15930   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(TapeTime));
15931
15932   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ScreenMovDir));
15933   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ScreenMovPos));
15934   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ScreenGfxPos));
15935
15936   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ScrollStepSize));
15937
15938   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(AmoebaCnt));
15939   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(AmoebaCnt2));
15940
15941   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(Tile));
15942   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(MovPos));
15943   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(MovDir));
15944   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(MovDelay));
15945   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ChangeDelay));
15946   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ChangePage));
15947   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(CustomValue));
15948   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(Store));
15949   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(Store2));
15950   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(StorePlayer));
15951   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(Back));
15952   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(AmoebaNr));
15953   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(WasJustMoving));
15954   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(WasJustFalling));
15955   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(CheckCollision));
15956   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(CheckImpact));
15957   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(Stop));
15958   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(Pushed));
15959
15960   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ChangeCount));
15961   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ChangeEvent));
15962
15963   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ExplodePhase));
15964   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ExplodeDelay));
15965   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(ExplodeField));
15966
15967   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(RunnerVisit));
15968   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(PlayerVisit));
15969
15970   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(GfxFrame));
15971   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(GfxRandom));
15972   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(GfxRandomStatic));
15973   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(GfxElement));
15974   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(GfxAction));
15975   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(GfxDir));
15976
15977   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(scroll_x));
15978   SaveSnapshotBuffer(&buffers, ARGS_ADDRESS_AND_SIZEOF(scroll_y));
15979
15980 #if 0
15981   ListNode *node = engine_snapshot_list_rnd;
15982   int num_bytes = 0;
15983
15984   while (node != NULL)
15985   {
15986     num_bytes += ((struct EngineSnapshotNodeInfo *)node->content)->size;
15987
15988     node = node->next;
15989   }
15990
15991   Debug("game:playing:SaveEngineSnapshotBuffers",
15992         "size of engine snapshot: %d bytes", num_bytes);
15993 #endif
15994
15995   return buffers;
15996 }
15997
15998 void SaveEngineSnapshotSingle(void)
15999 {
16000   ListNode *buffers = SaveEngineSnapshotBuffers();
16001
16002   // finally save all snapshot buffers to single snapshot
16003   SaveSnapshotSingle(buffers);
16004
16005   // save level identification information
16006   setString(&snapshot_level_identifier, leveldir_current->identifier);
16007   snapshot_level_nr = level_nr;
16008 }
16009
16010 boolean CheckSaveEngineSnapshotToList(void)
16011 {
16012   boolean save_snapshot =
16013     ((game.snapshot.mode == SNAPSHOT_MODE_EVERY_STEP) ||
16014      (game.snapshot.mode == SNAPSHOT_MODE_EVERY_MOVE &&
16015       game.snapshot.changed_action) ||
16016      (game.snapshot.mode == SNAPSHOT_MODE_EVERY_COLLECT &&
16017       game.snapshot.collected_item));
16018
16019   game.snapshot.changed_action = FALSE;
16020   game.snapshot.collected_item = FALSE;
16021   game.snapshot.save_snapshot = save_snapshot;
16022
16023   return save_snapshot;
16024 }
16025
16026 void SaveEngineSnapshotToList(void)
16027 {
16028   if (game.snapshot.mode == SNAPSHOT_MODE_OFF ||
16029       tape.quick_resume)
16030     return;
16031
16032   ListNode *buffers = SaveEngineSnapshotBuffers();
16033
16034   // finally save all snapshot buffers to snapshot list
16035   SaveSnapshotToList(buffers);
16036 }
16037
16038 void SaveEngineSnapshotToListInitial(void)
16039 {
16040   FreeEngineSnapshotList();
16041
16042   SaveEngineSnapshotToList();
16043 }
16044
16045 static void LoadEngineSnapshotValues(void)
16046 {
16047   // restore special values from snapshot structure
16048
16049   if (level.game_engine_type == GAME_ENGINE_TYPE_RND)
16050     LoadEngineSnapshotValues_RND();
16051   if (level.game_engine_type == GAME_ENGINE_TYPE_EM)
16052     LoadEngineSnapshotValues_EM();
16053   if (level.game_engine_type == GAME_ENGINE_TYPE_SP)
16054     LoadEngineSnapshotValues_SP();
16055   if (level.game_engine_type == GAME_ENGINE_TYPE_MM)
16056     LoadEngineSnapshotValues_MM();
16057 }
16058
16059 void LoadEngineSnapshotSingle(void)
16060 {
16061   LoadSnapshotSingle();
16062
16063   LoadEngineSnapshotValues();
16064 }
16065
16066 static void LoadEngineSnapshot_Undo(int steps)
16067 {
16068   LoadSnapshotFromList_Older(steps);
16069
16070   LoadEngineSnapshotValues();
16071 }
16072
16073 static void LoadEngineSnapshot_Redo(int steps)
16074 {
16075   LoadSnapshotFromList_Newer(steps);
16076
16077   LoadEngineSnapshotValues();
16078 }
16079
16080 boolean CheckEngineSnapshotSingle(void)
16081 {
16082   return (strEqual(snapshot_level_identifier, leveldir_current->identifier) &&
16083           snapshot_level_nr == level_nr);
16084 }
16085
16086 boolean CheckEngineSnapshotList(void)
16087 {
16088   return CheckSnapshotList();
16089 }
16090
16091
16092 // ---------- new game button stuff -------------------------------------------
16093
16094 static struct
16095 {
16096   int graphic;
16097   struct XY *pos;
16098   int gadget_id;
16099   boolean *setup_value;
16100   boolean allowed_on_tape;
16101   boolean is_touch_button;
16102   char *infotext;
16103 } gamebutton_info[NUM_GAME_BUTTONS] =
16104 {
16105   {
16106     IMG_GFX_GAME_BUTTON_STOP,                   &game.button.stop,
16107     GAME_CTRL_ID_STOP,                          NULL,
16108     TRUE, FALSE,                                "stop game"
16109   },
16110   {
16111     IMG_GFX_GAME_BUTTON_PAUSE,                  &game.button.pause,
16112     GAME_CTRL_ID_PAUSE,                         NULL,
16113     TRUE, FALSE,                                "pause game"
16114   },
16115   {
16116     IMG_GFX_GAME_BUTTON_PLAY,                   &game.button.play,
16117     GAME_CTRL_ID_PLAY,                          NULL,
16118     TRUE, FALSE,                                "play game"
16119   },
16120   {
16121     IMG_GFX_GAME_BUTTON_UNDO,                   &game.button.undo,
16122     GAME_CTRL_ID_UNDO,                          NULL,
16123     TRUE, FALSE,                                "undo step"
16124   },
16125   {
16126     IMG_GFX_GAME_BUTTON_REDO,                   &game.button.redo,
16127     GAME_CTRL_ID_REDO,                          NULL,
16128     TRUE, FALSE,                                "redo step"
16129   },
16130   {
16131     IMG_GFX_GAME_BUTTON_SAVE,                   &game.button.save,
16132     GAME_CTRL_ID_SAVE,                          NULL,
16133     TRUE, FALSE,                                "save game"
16134   },
16135   {
16136     IMG_GFX_GAME_BUTTON_PAUSE2,                 &game.button.pause2,
16137     GAME_CTRL_ID_PAUSE2,                        NULL,
16138     TRUE, FALSE,                                "pause game"
16139   },
16140   {
16141     IMG_GFX_GAME_BUTTON_LOAD,                   &game.button.load,
16142     GAME_CTRL_ID_LOAD,                          NULL,
16143     TRUE, FALSE,                                "load game"
16144   },
16145   {
16146     IMG_GFX_GAME_BUTTON_PANEL_STOP,             &game.button.panel_stop,
16147     GAME_CTRL_ID_PANEL_STOP,                    NULL,
16148     FALSE, FALSE,                               "stop game"
16149   },
16150   {
16151     IMG_GFX_GAME_BUTTON_PANEL_PAUSE,            &game.button.panel_pause,
16152     GAME_CTRL_ID_PANEL_PAUSE,                   NULL,
16153     FALSE, FALSE,                               "pause game"
16154   },
16155   {
16156     IMG_GFX_GAME_BUTTON_PANEL_PLAY,             &game.button.panel_play,
16157     GAME_CTRL_ID_PANEL_PLAY,                    NULL,
16158     FALSE, FALSE,                               "play game"
16159   },
16160   {
16161     IMG_GFX_GAME_BUTTON_TOUCH_STOP,             &game.button.touch_stop,
16162     GAME_CTRL_ID_TOUCH_STOP,                    NULL,
16163     FALSE, TRUE,                                "stop game"
16164   },
16165   {
16166     IMG_GFX_GAME_BUTTON_TOUCH_PAUSE,            &game.button.touch_pause,
16167     GAME_CTRL_ID_TOUCH_PAUSE,                   NULL,
16168     FALSE, TRUE,                                "pause game"
16169   },
16170   {
16171     IMG_GFX_GAME_BUTTON_SOUND_MUSIC,            &game.button.sound_music,
16172     SOUND_CTRL_ID_MUSIC,                        &setup.sound_music,
16173     TRUE, FALSE,                                "background music on/off"
16174   },
16175   {
16176     IMG_GFX_GAME_BUTTON_SOUND_LOOPS,            &game.button.sound_loops,
16177     SOUND_CTRL_ID_LOOPS,                        &setup.sound_loops,
16178     TRUE, FALSE,                                "sound loops on/off"
16179   },
16180   {
16181     IMG_GFX_GAME_BUTTON_SOUND_SIMPLE,           &game.button.sound_simple,
16182     SOUND_CTRL_ID_SIMPLE,                       &setup.sound_simple,
16183     TRUE, FALSE,                                "normal sounds on/off"
16184   },
16185   {
16186     IMG_GFX_GAME_BUTTON_PANEL_SOUND_MUSIC,      &game.button.panel_sound_music,
16187     SOUND_CTRL_ID_PANEL_MUSIC,                  &setup.sound_music,
16188     FALSE, FALSE,                               "background music on/off"
16189   },
16190   {
16191     IMG_GFX_GAME_BUTTON_PANEL_SOUND_LOOPS,      &game.button.panel_sound_loops,
16192     SOUND_CTRL_ID_PANEL_LOOPS,                  &setup.sound_loops,
16193     FALSE, FALSE,                               "sound loops on/off"
16194   },
16195   {
16196     IMG_GFX_GAME_BUTTON_PANEL_SOUND_SIMPLE,     &game.button.panel_sound_simple,
16197     SOUND_CTRL_ID_PANEL_SIMPLE,                 &setup.sound_simple,
16198     FALSE, FALSE,                               "normal sounds on/off"
16199   }
16200 };
16201
16202 void CreateGameButtons(void)
16203 {
16204   int i;
16205
16206   for (i = 0; i < NUM_GAME_BUTTONS; i++)
16207   {
16208     int graphic = gamebutton_info[i].graphic;
16209     struct GraphicInfo *gfx = &graphic_info[graphic];
16210     struct XY *pos = gamebutton_info[i].pos;
16211     struct GadgetInfo *gi;
16212     int button_type;
16213     boolean checked;
16214     unsigned int event_mask;
16215     boolean is_touch_button = gamebutton_info[i].is_touch_button;
16216     boolean allowed_on_tape = gamebutton_info[i].allowed_on_tape;
16217     boolean on_tape = (tape.show_game_buttons && allowed_on_tape);
16218     int base_x = (is_touch_button ? 0 : on_tape ? VX : DX);
16219     int base_y = (is_touch_button ? 0 : on_tape ? VY : DY);
16220     int gd_x   = gfx->src_x;
16221     int gd_y   = gfx->src_y;
16222     int gd_xp  = gfx->src_x + gfx->pressed_xoffset;
16223     int gd_yp  = gfx->src_y + gfx->pressed_yoffset;
16224     int gd_xa  = gfx->src_x + gfx->active_xoffset;
16225     int gd_ya  = gfx->src_y + gfx->active_yoffset;
16226     int gd_xap = gfx->src_x + gfx->active_xoffset + gfx->pressed_xoffset;
16227     int gd_yap = gfx->src_y + gfx->active_yoffset + gfx->pressed_yoffset;
16228     int x = (is_touch_button ? pos->x : GDI_ACTIVE_POS(pos->x));
16229     int y = (is_touch_button ? pos->y : GDI_ACTIVE_POS(pos->y));
16230     int id = i;
16231
16232     // do not use touch buttons if overlay touch buttons are disabled
16233     if (is_touch_button && !setup.touch.overlay_buttons)
16234       continue;
16235
16236     if (gfx->bitmap == NULL)
16237     {
16238       game_gadget[id] = NULL;
16239
16240       continue;
16241     }
16242
16243     if (id == GAME_CTRL_ID_STOP ||
16244         id == GAME_CTRL_ID_PANEL_STOP ||
16245         id == GAME_CTRL_ID_TOUCH_STOP ||
16246         id == GAME_CTRL_ID_PLAY ||
16247         id == GAME_CTRL_ID_PANEL_PLAY ||
16248         id == GAME_CTRL_ID_SAVE ||
16249         id == GAME_CTRL_ID_LOAD)
16250     {
16251       button_type = GD_TYPE_NORMAL_BUTTON;
16252       checked = FALSE;
16253       event_mask = GD_EVENT_RELEASED;
16254     }
16255     else if (id == GAME_CTRL_ID_UNDO ||
16256              id == GAME_CTRL_ID_REDO)
16257     {
16258       button_type = GD_TYPE_NORMAL_BUTTON;
16259       checked = FALSE;
16260       event_mask = GD_EVENT_PRESSED | GD_EVENT_REPEATED;
16261     }
16262     else
16263     {
16264       button_type = GD_TYPE_CHECK_BUTTON;
16265       checked = (gamebutton_info[i].setup_value != NULL ?
16266                  *gamebutton_info[i].setup_value : FALSE);
16267       event_mask = GD_EVENT_PRESSED;
16268     }
16269
16270     gi = CreateGadget(GDI_CUSTOM_ID, id,
16271                       GDI_IMAGE_ID, graphic,
16272                       GDI_INFO_TEXT, gamebutton_info[i].infotext,
16273                       GDI_X, base_x + x,
16274                       GDI_Y, base_y + y,
16275                       GDI_WIDTH, gfx->width,
16276                       GDI_HEIGHT, gfx->height,
16277                       GDI_TYPE, button_type,
16278                       GDI_STATE, GD_BUTTON_UNPRESSED,
16279                       GDI_CHECKED, checked,
16280                       GDI_DESIGN_UNPRESSED, gfx->bitmap, gd_x, gd_y,
16281                       GDI_DESIGN_PRESSED, gfx->bitmap, gd_xp, gd_yp,
16282                       GDI_ALT_DESIGN_UNPRESSED, gfx->bitmap, gd_xa, gd_ya,
16283                       GDI_ALT_DESIGN_PRESSED, gfx->bitmap, gd_xap, gd_yap,
16284                       GDI_DIRECT_DRAW, FALSE,
16285                       GDI_OVERLAY_TOUCH_BUTTON, is_touch_button,
16286                       GDI_EVENT_MASK, event_mask,
16287                       GDI_CALLBACK_ACTION, HandleGameButtons,
16288                       GDI_END);
16289
16290     if (gi == NULL)
16291       Fail("cannot create gadget");
16292
16293     game_gadget[id] = gi;
16294   }
16295 }
16296
16297 void FreeGameButtons(void)
16298 {
16299   int i;
16300
16301   for (i = 0; i < NUM_GAME_BUTTONS; i++)
16302     FreeGadget(game_gadget[i]);
16303 }
16304
16305 static void UnmapGameButtonsAtSamePosition(int id)
16306 {
16307   int i;
16308
16309   for (i = 0; i < NUM_GAME_BUTTONS; i++)
16310     if (i != id &&
16311         gamebutton_info[i].pos->x == gamebutton_info[id].pos->x &&
16312         gamebutton_info[i].pos->y == gamebutton_info[id].pos->y)
16313       UnmapGadget(game_gadget[i]);
16314 }
16315
16316 static void UnmapGameButtonsAtSamePosition_All(void)
16317 {
16318   if (setup.show_load_save_buttons)
16319   {
16320     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_SAVE);
16321     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PAUSE2);
16322     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_LOAD);
16323   }
16324   else if (setup.show_undo_redo_buttons)
16325   {
16326     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_UNDO);
16327     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PAUSE2);
16328     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_REDO);
16329   }
16330   else
16331   {
16332     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_STOP);
16333     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PAUSE);
16334     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PLAY);
16335
16336     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PANEL_STOP);
16337     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PANEL_PAUSE);
16338     UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_PANEL_PLAY);
16339   }
16340 }
16341
16342 void MapLoadSaveButtons(void)
16343 {
16344   UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_LOAD);
16345   UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_SAVE);
16346
16347   MapGadget(game_gadget[GAME_CTRL_ID_LOAD]);
16348   MapGadget(game_gadget[GAME_CTRL_ID_SAVE]);
16349 }
16350
16351 void MapUndoRedoButtons(void)
16352 {
16353   UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_UNDO);
16354   UnmapGameButtonsAtSamePosition(GAME_CTRL_ID_REDO);
16355
16356   MapGadget(game_gadget[GAME_CTRL_ID_UNDO]);
16357   MapGadget(game_gadget[GAME_CTRL_ID_REDO]);
16358 }
16359
16360 void ModifyPauseButtons(void)
16361 {
16362   static int ids[] =
16363   {
16364     GAME_CTRL_ID_PAUSE,
16365     GAME_CTRL_ID_PAUSE2,
16366     GAME_CTRL_ID_PANEL_PAUSE,
16367     GAME_CTRL_ID_TOUCH_PAUSE,
16368     -1
16369   };
16370   int i;
16371
16372   for (i = 0; ids[i] > -1; i++)
16373     ModifyGadget(game_gadget[ids[i]], GDI_CHECKED, tape.pausing, GDI_END);
16374 }
16375
16376 static void MapGameButtonsExt(boolean on_tape)
16377 {
16378   int i;
16379
16380   for (i = 0; i < NUM_GAME_BUTTONS; i++)
16381   {
16382     if ((i == GAME_CTRL_ID_UNDO ||
16383          i == GAME_CTRL_ID_REDO) &&
16384         game_status != GAME_MODE_PLAYING)
16385       continue;
16386
16387     if (!on_tape || gamebutton_info[i].allowed_on_tape)
16388       MapGadget(game_gadget[i]);
16389   }
16390
16391   UnmapGameButtonsAtSamePosition_All();
16392
16393   RedrawGameButtons();
16394 }
16395
16396 static void UnmapGameButtonsExt(boolean on_tape)
16397 {
16398   int i;
16399
16400   for (i = 0; i < NUM_GAME_BUTTONS; i++)
16401     if (!on_tape || gamebutton_info[i].allowed_on_tape)
16402       UnmapGadget(game_gadget[i]);
16403 }
16404
16405 static void RedrawGameButtonsExt(boolean on_tape)
16406 {
16407   int i;
16408
16409   for (i = 0; i < NUM_GAME_BUTTONS; i++)
16410     if (!on_tape || gamebutton_info[i].allowed_on_tape)
16411       RedrawGadget(game_gadget[i]);
16412 }
16413
16414 static void SetGadgetState(struct GadgetInfo *gi, boolean state)
16415 {
16416   if (gi == NULL)
16417     return;
16418
16419   gi->checked = state;
16420 }
16421
16422 static void RedrawSoundButtonGadget(int id)
16423 {
16424   int id2 = (id == SOUND_CTRL_ID_MUSIC        ? SOUND_CTRL_ID_PANEL_MUSIC :
16425              id == SOUND_CTRL_ID_LOOPS        ? SOUND_CTRL_ID_PANEL_LOOPS :
16426              id == SOUND_CTRL_ID_SIMPLE       ? SOUND_CTRL_ID_PANEL_SIMPLE :
16427              id == SOUND_CTRL_ID_PANEL_MUSIC  ? SOUND_CTRL_ID_MUSIC :
16428              id == SOUND_CTRL_ID_PANEL_LOOPS  ? SOUND_CTRL_ID_LOOPS :
16429              id == SOUND_CTRL_ID_PANEL_SIMPLE ? SOUND_CTRL_ID_SIMPLE :
16430              id);
16431
16432   SetGadgetState(game_gadget[id2], *gamebutton_info[id2].setup_value);
16433   RedrawGadget(game_gadget[id2]);
16434 }
16435
16436 void MapGameButtons(void)
16437 {
16438   MapGameButtonsExt(FALSE);
16439 }
16440
16441 void UnmapGameButtons(void)
16442 {
16443   UnmapGameButtonsExt(FALSE);
16444 }
16445
16446 void RedrawGameButtons(void)
16447 {
16448   RedrawGameButtonsExt(FALSE);
16449 }
16450
16451 void MapGameButtonsOnTape(void)
16452 {
16453   MapGameButtonsExt(TRUE);
16454 }
16455
16456 void UnmapGameButtonsOnTape(void)
16457 {
16458   UnmapGameButtonsExt(TRUE);
16459 }
16460
16461 void RedrawGameButtonsOnTape(void)
16462 {
16463   RedrawGameButtonsExt(TRUE);
16464 }
16465
16466 static void GameUndoRedoExt(void)
16467 {
16468   ClearPlayerAction();
16469
16470   tape.pausing = TRUE;
16471
16472   RedrawPlayfield();
16473   UpdateAndDisplayGameControlValues();
16474
16475   DrawCompleteVideoDisplay();
16476   DrawVideoDisplay(VIDEO_STATE_TIME_ON, TapeTime);
16477   DrawVideoDisplay(VIDEO_STATE_FRAME_ON, FrameCounter);
16478   DrawVideoDisplay(VIDEO_STATE_1STEP(tape.single_step), 0);
16479
16480   ModifyPauseButtons();
16481
16482   BackToFront();
16483 }
16484
16485 static void GameUndo(int steps)
16486 {
16487   if (!CheckEngineSnapshotList())
16488     return;
16489
16490   int tape_property_bits = tape.property_bits;
16491
16492   LoadEngineSnapshot_Undo(steps);
16493
16494   tape.property_bits |= tape_property_bits | TAPE_PROPERTY_SNAPSHOT;
16495
16496   GameUndoRedoExt();
16497 }
16498
16499 static void GameRedo(int steps)
16500 {
16501   if (!CheckEngineSnapshotList())
16502     return;
16503
16504   int tape_property_bits = tape.property_bits;
16505
16506   LoadEngineSnapshot_Redo(steps);
16507
16508   tape.property_bits |= tape_property_bits | TAPE_PROPERTY_SNAPSHOT;
16509
16510   GameUndoRedoExt();
16511 }
16512
16513 static void HandleGameButtonsExt(int id, int button)
16514 {
16515   static boolean game_undo_executed = FALSE;
16516   int steps = BUTTON_STEPSIZE(button);
16517   boolean handle_game_buttons =
16518     (game_status == GAME_MODE_PLAYING ||
16519      (game_status == GAME_MODE_MAIN && tape.show_game_buttons));
16520
16521   if (!handle_game_buttons)
16522     return;
16523
16524   switch (id)
16525   {
16526     case GAME_CTRL_ID_STOP:
16527     case GAME_CTRL_ID_PANEL_STOP:
16528     case GAME_CTRL_ID_TOUCH_STOP:
16529       TapeStopGame();
16530
16531       break;
16532
16533     case GAME_CTRL_ID_PAUSE:
16534     case GAME_CTRL_ID_PAUSE2:
16535     case GAME_CTRL_ID_PANEL_PAUSE:
16536     case GAME_CTRL_ID_TOUCH_PAUSE:
16537       if (network.enabled && game_status == GAME_MODE_PLAYING)
16538       {
16539         if (tape.pausing)
16540           SendToServer_ContinuePlaying();
16541         else
16542           SendToServer_PausePlaying();
16543       }
16544       else
16545         TapeTogglePause(TAPE_TOGGLE_MANUAL);
16546
16547       game_undo_executed = FALSE;
16548
16549       break;
16550
16551     case GAME_CTRL_ID_PLAY:
16552     case GAME_CTRL_ID_PANEL_PLAY:
16553       if (game_status == GAME_MODE_MAIN)
16554       {
16555         StartGameActions(network.enabled, setup.autorecord, level.random_seed);
16556       }
16557       else if (tape.pausing)
16558       {
16559         if (network.enabled)
16560           SendToServer_ContinuePlaying();
16561         else
16562           TapeTogglePause(TAPE_TOGGLE_MANUAL | TAPE_TOGGLE_PLAY_PAUSE);
16563       }
16564       break;
16565
16566     case GAME_CTRL_ID_UNDO:
16567       // Important: When using "save snapshot when collecting an item" mode,
16568       // load last (current) snapshot for first "undo" after pressing "pause"
16569       // (else the last-but-one snapshot would be loaded, because the snapshot
16570       // pointer already points to the last snapshot when pressing "pause",
16571       // which is fine for "every step/move" mode, but not for "every collect")
16572       if (game.snapshot.mode == SNAPSHOT_MODE_EVERY_COLLECT &&
16573           !game_undo_executed)
16574         steps--;
16575
16576       game_undo_executed = TRUE;
16577
16578       GameUndo(steps);
16579       break;
16580
16581     case GAME_CTRL_ID_REDO:
16582       GameRedo(steps);
16583       break;
16584
16585     case GAME_CTRL_ID_SAVE:
16586       TapeQuickSave();
16587       break;
16588
16589     case GAME_CTRL_ID_LOAD:
16590       TapeQuickLoad();
16591       break;
16592
16593     case SOUND_CTRL_ID_MUSIC:
16594     case SOUND_CTRL_ID_PANEL_MUSIC:
16595       if (setup.sound_music)
16596       {
16597         setup.sound_music = FALSE;
16598
16599         FadeMusic();
16600       }
16601       else if (audio.music_available)
16602       {
16603         setup.sound = setup.sound_music = TRUE;
16604
16605         SetAudioMode(setup.sound);
16606
16607         if (game_status == GAME_MODE_PLAYING)
16608           PlayLevelMusic();
16609       }
16610
16611       RedrawSoundButtonGadget(id);
16612
16613       break;
16614
16615     case SOUND_CTRL_ID_LOOPS:
16616     case SOUND_CTRL_ID_PANEL_LOOPS:
16617       if (setup.sound_loops)
16618         setup.sound_loops = FALSE;
16619       else if (audio.loops_available)
16620       {
16621         setup.sound = setup.sound_loops = TRUE;
16622
16623         SetAudioMode(setup.sound);
16624       }
16625
16626       RedrawSoundButtonGadget(id);
16627
16628       break;
16629
16630     case SOUND_CTRL_ID_SIMPLE:
16631     case SOUND_CTRL_ID_PANEL_SIMPLE:
16632       if (setup.sound_simple)
16633         setup.sound_simple = FALSE;
16634       else if (audio.sound_available)
16635       {
16636         setup.sound = setup.sound_simple = TRUE;
16637
16638         SetAudioMode(setup.sound);
16639       }
16640
16641       RedrawSoundButtonGadget(id);
16642
16643       break;
16644
16645     default:
16646       break;
16647   }
16648 }
16649
16650 static void HandleGameButtons(struct GadgetInfo *gi)
16651 {
16652   HandleGameButtonsExt(gi->custom_id, gi->event.button);
16653 }
16654
16655 void HandleSoundButtonKeys(Key key)
16656 {
16657   if (key == setup.shortcut.sound_simple)
16658     ClickOnGadget(game_gadget[SOUND_CTRL_ID_SIMPLE], MB_LEFTBUTTON);
16659   else if (key == setup.shortcut.sound_loops)
16660     ClickOnGadget(game_gadget[SOUND_CTRL_ID_LOOPS], MB_LEFTBUTTON);
16661   else if (key == setup.shortcut.sound_music)
16662     ClickOnGadget(game_gadget[SOUND_CTRL_ID_MUSIC], MB_LEFTBUTTON);
16663 }