improved readability of some condition checks in EM engine

[rocksndiamonds.git] / src / game_em / synchro_2.c

diff --git a/src/game_em/synchro_2.c b/src/game_em/synchro_2.c
index eb202c7c302baecbabacb5b46310ee359079f2df..687747350d4a4f750192c92245743fba8dbc5ccd 100644 (file)
--- a/src/game_em/synchro_2.c
+++ b/src/game_em/synchro_2.c
@@ -13,9 +13,10 @@
 
 #define SPRING_ROLL    /* spring rolling off round things continues to roll */
 
-#define RANDOM (random_em = random_em << 31 | random_em >> 1)
+#define RANDOM_RAW     (seed = seed << 31 | seed >> 1)
+#define RANDOM(x)      (RANDOM_RAW & (x - 1))
 
-static unsigned int random_em;
+static unsigned int seed;
 static int score;
 
 static void set_nearest_player_xy(int x, int y, int *dx, int *dy)
@@ -95,7 +96,7 @@ static void Landroid(int x, int y)
        Cave[y+1][x+1] != Xblank)
       goto android_move;
 
-    switch (RANDOM & 7)
+    switch (RANDOM(8))
     {
       /* randomly find an object to clone */
 
@@ -191,7 +192,7 @@ static void Landroid(int x, int y)
     Next[y][x] = temp; /* the item we chose to clone */
     play_element_sound(x, y, SOUND_android_clone, temp);
 
-    switch (RANDOM & 7)
+    switch (RANDOM(8))
     {
       /* randomly find a direction to move */
 
@@ -303,7 +304,7 @@ static void Landroid(int x, int y)
     Next[y][x] = Xblank;       /* assume we will move */
     temp = ((x < dx) + 1 - (x > dx)) + ((y < dy) + 1 - (y > dy)) * 3;
 
-    if (RANDOM & 1)
+    if (RANDOM(2))
     {
       switch (temp)
       {
@@ -844,7 +845,7 @@ static void Leater_n(int x, int y)
       return;
 
     default:
-      Next[y][x] = RANDOM & 1 ? Xeater_e : Xeater_w;
+      Next[y][x] = RANDOM(2) ? Xeater_e : Xeater_w;
       play_element_sound(x, y, SOUND_eater, Xeater_n);
       return;
   }
@@ -916,7 +917,7 @@ static void Leater_e(int x, int y)
       return;
 
     default:
-      Next[y][x] = RANDOM & 1 ? Xeater_n : Xeater_s;
+      Next[y][x] = RANDOM(2) ? Xeater_n : Xeater_s;
       play_element_sound(x, y, SOUND_eater, Xeater_e);
       return;
   }
@@ -988,7 +989,7 @@ static void Leater_s(int x, int y)
       return;
 
     default:
-      Next[y][x] = RANDOM & 1 ? Xeater_e : Xeater_w;
+      Next[y][x] = RANDOM(2) ? Xeater_e : Xeater_w;
       play_element_sound(x, y, SOUND_eater, Xeater_s);
       return;
   }
@@ -1060,7 +1061,7 @@ static void Leater_w(int x, int y)
       return;
 
     default:
-      Next[y][x] = RANDOM & 1 ? Xeater_n : Xeater_s;
+      Next[y][x] = RANDOM(2) ? Xeater_n : Xeater_s;
       play_element_sound(x, y, SOUND_eater, Xeater_w);
       return;
   }
@@ -1080,7 +1081,7 @@ static void Lalien(int x, int y)
     set_nearest_player_xy(x, y, &dx, &dy);
   }
 
-  if (RANDOM & 1)
+  if (RANDOM(2))
   {
     if (y > dy)
     {
@@ -2084,7 +2085,7 @@ static void Lemerald(int x, int y)
     case Xroundwall_2:
     case Xroundwall_3:
     case Xroundwall_4:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        if (tab_blank[Cave[y][x+1]] && tab_acid[Cave[y+1][x+1]])
        {
@@ -2128,7 +2129,7 @@ static void Lemerald(int x, int y)
     default:
       if (++lev.shine_cnt > 50)
       {
-       lev.shine_cnt = RANDOM & 7;
+       lev.shine_cnt = RANDOM(8);
        Cave[y][x] = Xemerald_shine;
       }
 
@@ -2311,7 +2312,7 @@ static void Ldiamond(int x, int y)
     case Xroundwall_2:
     case Xroundwall_3:
     case Xroundwall_4:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        if (tab_blank[Cave[y][x+1]] && tab_acid[Cave[y+1][x+1]])
        {
@@ -2355,7 +2356,7 @@ static void Ldiamond(int x, int y)
     default:
       if (++lev.shine_cnt > 50)
       {
-       lev.shine_cnt = RANDOM & 7;
+       lev.shine_cnt = RANDOM(8);
        Cave[y][x] = Xdiamond_shine;
       }
 
@@ -2481,7 +2482,7 @@ static void Lstone(int x, int y)
     case Xacid_splash_w:
     case Xplant:
     case Yplant:
-#if 1
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
     case Xfake_acid_1:
     case Xfake_acid_2:
     case Xfake_acid_3:
@@ -2550,7 +2551,7 @@ static void Lstone(int x, int y)
     case Xroundwall_2:
     case Xroundwall_3:
     case Xroundwall_4:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        if (tab_blank[Cave[y][x+1]] && tab_acid[Cave[y+1][x+1]])
        {
@@ -2617,7 +2618,7 @@ static void Lstone_pause(int x, int y)
     case Xblank:
     case Xacid_splash_e:
     case Xacid_splash_w:
-#if 1
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
     case Xfake_acid_1:
     case Xfake_acid_2:
     case Xfake_acid_3:
@@ -2665,7 +2666,7 @@ static void Lstone_fall(int x, int y)
     case Xacid_splash_e:
     case Xacid_splash_w:
     case Zplayer:
-#if 1
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
     case Xfake_acid_1:
     case Xfake_acid_2:
     case Xfake_acid_3:
@@ -2743,7 +2744,7 @@ static void Lstone_fall(int x, int y)
       return;
 
     case Xspring:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        switch (Cave[y+1][x+1])
        {
@@ -3002,7 +3003,7 @@ static void Lbomb(int x, int y)
     case Xroundwall_2:
     case Xroundwall_3:
     case Xroundwall_4:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        if (tab_blank[Cave[y][x+1]] && tab_acid[Cave[y+1][x+1]])
        {
@@ -3205,7 +3206,7 @@ static void Lnut(int x, int y)
     case Xroundwall_2:
     case Xroundwall_3:
     case Xroundwall_4:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        if (tab_blank[Cave[y][x+1]] && tab_acid[Cave[y+1][x+1]])
        {
@@ -3400,7 +3401,7 @@ static void Lspring(int x, int y)
     case Xroundwall_2:
     case Xroundwall_3:
     case Xroundwall_4:
-      if (RANDOM & 1)
+      if (RANDOM(2))
       {
        if (tab_blank[Cave[y][x+1]] && tab_acid[Cave[y+1][x+1]])
        {
@@ -4289,7 +4290,7 @@ static void Lball_common(int x, int y)
 
   if (lev.ball_random)
   {
-    switch (RANDOM & 7)
+    switch (RANDOM(8))
     {
       case 0:
        if (lev.ball_array[lev.ball_pos][0] != Xblank &&
@@ -4493,39 +4494,16 @@ static void Ldrip_fall(int x, int y)
       return;
 
     default:
-      switch (RANDOM & 7)
+      switch (RANDOM(8))
       {
-       case 0:
-         temp = Xamoeba_1;
-         break;
-
-       case 1:
-         temp = Xamoeba_2;
-         break;
-
-       case 2:
-         temp = Xamoeba_3;
-         break;
-
-       case 3:
-         temp = Xamoeba_4;
-         break;
-
-       case 4:
-         temp = Xamoeba_5;
-         break;
-
-       case 5:
-         temp = Xamoeba_6;
-         break;
-
-       case 6:
-         temp = Xamoeba_7;
-         break;
-
-       case 7:
-         temp = Xamoeba_8;
-         break;
+       case 0: temp = Xamoeba_1; break;
+       case 1: temp = Xamoeba_2; break;
+       case 2: temp = Xamoeba_3; break;
+       case 3: temp = Xamoeba_4; break;
+       case 4: temp = Xamoeba_5; break;
+       case 5: temp = Xamoeba_6; break;
+       case 6: temp = Xamoeba_7; break;
+       case 7: temp = Xamoeba_8; break;
       }
 
       Cave[y][x] = temp;
@@ -4635,7 +4613,7 @@ static void Lsand_stonesand_4(int x, int y)
   Next[y][x] = Xsand;
 }
 
-#if 1
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
 static void Lsand_stonesand_quickout_1(int x, int y)
 {
   Next[y][x] = Xsand_stonesand_quickout_2;
@@ -4716,22 +4694,22 @@ static void Lexit(int x, int y)
   if (lev.required > 0)
     return;
 
-  int temp = RANDOM & 63;
-
-  if (temp < 21)
-  {
-    Cave[y][x] = Xexit_1;
-    Next[y][x] = Xexit_2;
-  }
-  else if (temp < 42)
-  {
-    Cave[y][x] = Xexit_2;
-    Next[y][x] = Xexit_3;
-  }
-  else
+  switch (RANDOM(64) / 21)
   {
-    Cave[y][x] = Xexit_3;
-    Next[y][x] = Xexit_1;
+    case 0:
+      Cave[y][x] = Xexit_1;
+      Next[y][x] = Xexit_2;
+      break;
+
+    case 1:
+      Cave[y][x] = Xexit_2;
+      Next[y][x] = Xexit_3;
+      break;
+
+    default:
+      Cave[y][x] = Xexit_3;
+      Next[y][x] = Xexit_1;
+      break;
   }
 
   play_element_sound(x, y, SOUND_exit_open, Xexit);
@@ -4792,6 +4770,7 @@ static void Lacid_8(int x, int y)
   Next[y][x] = Xacid_1;
 }
 
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
 static void Lfake_acid_1(int x, int y)
 {
   Next[y][x] = Xfake_acid_2;
@@ -4831,6 +4810,7 @@ static void Lfake_acid_8(int x, int y)
 {
   Next[y][x] = Xfake_acid_1;
 }
+#endif
 
 static void Lpause(int x, int y)
 {
@@ -4980,7 +4960,7 @@ void synchro_2(void)
   short *cave_cache = Cave[y]; /* might be a win */
   int element;
 
-  random_em = RandomEM;
+  seed = RandomEM;
   score = 0;
 
  loop:
@@ -4998,6 +4978,7 @@ void synchro_2(void)
     case Xacid_7:              Lacid_7(x, y);                  goto loop;
     case Xacid_8:              Lacid_8(x, y);                  goto loop;
 
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
     case Xfake_acid_1:         Lfake_acid_1(x, y);             goto loop;
     case Xfake_acid_2:         Lfake_acid_2(x, y);             goto loop;
     case Xfake_acid_3:         Lfake_acid_3(x, y);             goto loop;
@@ -5006,6 +4987,7 @@ void synchro_2(void)
     case Xfake_acid_6:         Lfake_acid_6(x, y);             goto loop;
     case Xfake_acid_7:         Lfake_acid_7(x, y);             goto loop;
     case Xfake_acid_8:         Lfake_acid_8(x, y);             goto loop;
+#endif
 
     case Xandroid:             Landroid(x, y);                 goto loop;
     case Xandroid_1_n:         Landroid_1_n(x, y);             goto loop;
@@ -5131,7 +5113,7 @@ void synchro_2(void)
     case Xsand_stonesand_4:    Lsand_stonesand_4(x, y);        goto loop;
     case Xsand_stoneout_1:     Lsand_stoneout_1(x, y);         goto loop;
     case Xsand_stoneout_2:     Lsand_stoneout_2(x, y);         goto loop;
-#if 1
+#ifdef EM_ENGINE_USE_ADDITIONAL_ELEMENTS
     case Xsand_stonesand_quickout_1:Lsand_stonesand_quickout_1(x, y);goto loop;
     case Xsand_stonesand_quickout_2:Lsand_stonesand_quickout_2(x, y);goto loop;
 #endif
@@ -5166,10 +5148,6 @@ void synchro_2(void)
       goto loop;
   }
 
-#undef RANDOM
-#undef PLAY
-#undef PLAY_FORCE
-
  done:
 
   if (ply[0].alive || ply[1].alive || ply[2].alive || ply[3].alive)
@@ -5177,7 +5155,7 @@ void synchro_2(void)
   else
     game_em.game_over = TRUE;
 
-  RandomEM = random_em;
+  RandomEM = seed;
 
   {
     void *temp = Cave;