From: Holger Schemel <info@artsoft.org>
Date: Thu, 30 Mar 2023 19:36:06 +0000 (+0200)
Subject: fixed several bugs with shared playfield bitmap in MM game engine
X-Git-Tag: 4.3.5.3~12
X-Git-Url: https://git.artsoft.org/?p=rocksndiamonds.git;a=commitdiff_plain;h=b66bf285376f1a2c08ba8f7624fa48ffbcd898a9

fixed several bugs with shared playfield bitmap in MM game engine

This fixes several bugs that resulted from using the normal background
bitmap for the Mirror Magic game engine (which was possible because
this game engine does not support scrolling levels and therefore only
uses the visible playfield viewport).

The main bugs fixed by this change are preventing MM engine levels
that are larger than the visible playfield area drawing over the
border area, and some problems with envelope style requests (like
restoring an outdated copy of the backbuffer after an envelope
request was answered after a game was lost).

While fixing these visible bugs, this change also brings a cleanup of
the MM engine code, which used three different bitmap pointers before
(that all pointed to the same backbuffer bitmap).
---

diff --git a/src/engines.h b/src/engines.h
index 142c064f..f2f9fe2f 100644
--- a/src/engines.h
+++ b/src/engines.h
@@ -59,12 +59,13 @@ boolean isNextAnimationFrame_SP(int, int);
 // ============================================================================
 
 void SetDrawtoField(int);
+void BackToFront(void);
 
 int el2img_mm(int);
 int el_act2img_mm(int, int);
 
 void CheckSingleStepMode_MM(boolean, boolean);
-void ShowEnvelope_MM(int);
+void ShowEnvelope(int);
 
 int getGraphicAnimationFrame(int, int);
 int getGraphicAnimationFrameXY(int, int, int);
diff --git a/src/game_mm/mm_game.c b/src/game_mm/mm_game.c
index 5cdc8ed3..c5cfa1d5 100644
--- a/src/game_mm/mm_game.c
+++ b/src/game_mm/mm_game.c
@@ -364,7 +364,7 @@ static void DrawLaserLines(struct XY *points, int num_points, int mode)
   Pixel pixel_drawto = (mode == DL_LASER_ENABLED ? pen_ray     : pen_bg);
   Pixel pixel_buffer = (mode == DL_LASER_ENABLED ? WHITE_PIXEL : BLACK_PIXEL);
 
-  DrawLines(drawto, points, num_points, pixel_drawto);
+  DrawLines(drawto_mm, points, num_points, pixel_drawto);
 
   BEGIN_NO_HEADLESS
   {
@@ -644,8 +644,8 @@ void InitGameEngine_MM(void)
   BEGIN_NO_HEADLESS
   {
     // initialize laser bitmap to current playfield (screen) size
-    ReCreateBitmap(&laser_bitmap, drawto->width, drawto->height);
-    ClearRectangle(laser_bitmap, 0, 0, drawto->width, drawto->height);
+    ReCreateBitmap(&laser_bitmap, drawto_mm->width, drawto_mm->height);
+    ClearRectangle(laser_bitmap, 0, 0, drawto_mm->width, drawto_mm->height);
   }
   END_NO_HEADLESS
 
@@ -762,7 +762,7 @@ void InitGameActions_MM(void)
 
     DrawLevel_MM();
 
-    BackToFront();
+    BackToFront_MM();
 
 #ifdef DEBUG
     if (setup.quick_doors)
@@ -795,7 +795,7 @@ static void FadeOutLaser(void)
 
     DrawLaser(0, DL_LASER_ENABLED);
 
-    BackToFront();
+    BackToFront_MM();
     Delay_WithScreenUpdates(50);
   }
 
@@ -2567,7 +2567,7 @@ static void OpenGrayBall(int x, int y)
       DrawWalls_MM(x, y, Store[x][y]);
 
       // copy wall tile to spare bitmap for "melting" animation
-      BlitBitmap(drawto, bitmap_db_field, cSX + x * TILEX, cSY + y * TILEY,
+      BlitBitmap(drawto_mm, bitmap_db_field, cSX + x * TILEX, cSY + y * TILEY,
 		 TILEX, TILEY, x * TILEX, y * TILEY);
 
       DrawElement_MM(x, y, EL_GRAY_BALL);
@@ -2600,7 +2600,7 @@ static void OpenGrayBall(int x, int y)
 	getGraphicSource(graphic, 0, &bitmap, &gx, &gy);
       }
 
-      BlitBitmap(bitmap, drawto, gx + dx, gy + dy, 6, 6,
+      BlitBitmap(bitmap, drawto_mm, gx + dx, gy + dy, 6, 6,
 		 cSX + x * TILEX + dx, cSY + y * TILEY + dy);
 
       laser.redraw = TRUE;
@@ -2653,7 +2653,7 @@ static void OpenEnvelope(int x, int y)
 
       ScanLaser();
 
-      ShowEnvelope_MM(nr);
+      ShowEnvelope(nr);
     }
   }
 }
@@ -3750,7 +3750,7 @@ static void GameActions_MM_Ext(void)
 
       UpdateAndDisplayGameControlValues();
 
-      BackToFront();
+      BackToFront_MM();
     }
 
     Tile[ELX][ELY] = laser.dest_element = EL_FUEL_EMPTY;
@@ -3849,7 +3849,7 @@ static void MovePacMen(void)
     }
 
     DrawField_MM(nx, ny);
-    BackToFront();
+    BackToFront_MM();
 
     if (!laser.fuse_off)
     {
diff --git a/src/game_mm/mm_init.c b/src/game_mm/mm_init.c
index a82b61df..d982d190 100644
--- a/src/game_mm/mm_init.c
+++ b/src/game_mm/mm_init.c
@@ -14,9 +14,16 @@
 #include "mm_main.h"
 
 
+Bitmap *drawto_mm;
+
 struct EngineSnapshotInfo_MM engine_snapshot_mm;
 
 
+void InitGfxBuffers_MM(void)
+{
+  ReCreateBitmap(&drawto_mm, video.width, video.height);
+}
+
 unsigned int InitEngineRandom_MM(int seed)
 {
   return InitEngineRandom(seed);
diff --git a/src/game_mm/mm_main.h b/src/game_mm/mm_main.h
index 1404fb03..16246b2b 100644
--- a/src/game_mm/mm_main.h
+++ b/src/game_mm/mm_main.h
@@ -181,7 +181,7 @@
 #define LEVEL_SCORE_ELEMENTS	16	// level elements with score
 
 
-extern DrawBuffer      *drawto_field;
+extern DrawBuffer      *drawto_mm;
 extern DrawBuffer      *bitmap_db_field;
 
 extern int		game_status;
diff --git a/src/game_mm/mm_tools.c b/src/game_mm/mm_tools.c
index dd7edbdf..39bb2467 100644
--- a/src/game_mm/mm_tools.c
+++ b/src/game_mm/mm_tools.c
@@ -41,9 +41,16 @@ void SetDrawtoField_MM(int mode)
   SetTileCursorSXSY(cSX, cSY);
 }
 
+void BackToFront_MM(void)
+{
+  BlitScreenToBitmap_MM(backbuffer);
+
+  BackToFront();
+}
+
 void ClearWindow(void)
 {
-  ClearRectangle(backbuffer, REAL_SX, REAL_SY, FULL_SXSIZE, FULL_SYSIZE);
+  ClearRectangle(drawto_mm, REAL_SX, REAL_SY, FULL_SXSIZE, FULL_SYSIZE);
 
   SetDrawtoField(DRAW_TO_BACKBUFFER);
   SetDrawtoField_MM(DRAW_TO_BACKBUFFER);
@@ -58,7 +65,7 @@ void DrawGraphicAnimation_MM(int x, int y, int graphic, int frame)
 
   getGraphicSource(graphic, frame, &bitmap, &src_x, &src_y);
 
-  BlitBitmap(bitmap, drawto_field, src_x, src_y, TILEX, TILEY,
+  BlitBitmap(bitmap, drawto_mm, src_x, src_y, TILEX, TILEY,
 	     cFX + x * TILEX, cFY + y * TILEY);
 }
 
@@ -105,7 +112,7 @@ void DrawGraphicThruMask_MM(int x, int y, int graphic, int frame)
   }
 #endif
 
-  DrawGraphicThruMaskExt_MM(drawto_field, cFX + x * TILEX, cFY + y * TILEY,
+  DrawGraphicThruMaskExt_MM(drawto_mm, cFX + x * TILEX, cFY + y * TILEY,
 			    graphic, frame);
 
   MarkTileDirty(x,y);
@@ -127,7 +134,7 @@ void DrawGraphicThruMaskExt_MM(DrawBuffer *d, int dest_x, int dest_y,
 
 void DrawMiniGraphic_MM(int x, int y, int graphic)
 {
-  DrawMiniGraphicExt_MM(drawto, cSX + x * MINI_TILEX, cSY + y * MINI_TILEY,
+  DrawMiniGraphicExt_MM(drawto_mm, cSX + x * MINI_TILEX, cSY + y * MINI_TILEY,
 			graphic);
 
   MarkTileDirty(x / 2, y / 2);
@@ -246,10 +253,10 @@ void DrawGraphicShifted_MM(int x,int y, int dx,int dy, int graphic,
 #endif
 
   if (mask_mode == USE_MASKING)
-    BlitBitmapMasked(src_bitmap, drawto_field,
+    BlitBitmapMasked(src_bitmap, drawto_mm,
 		     src_x, src_y, TILEX, TILEY, dest_x, dest_y);
   else
-    BlitBitmap(src_bitmap, drawto_field,
+    BlitBitmap(src_bitmap, drawto_mm,
 	       src_x, src_y, width, height, dest_x, dest_y);
 
   MarkTileDirty(x,y);
@@ -434,10 +441,10 @@ void DrawWallsExt_MM(int x, int y, int element, int draw_mask)
       continue;
 
     if (element & (1 << i))
-      BlitBitmap(bitmap, drawto, gx, gy, MINI_TILEX, MINI_TILEY,
+      BlitBitmap(bitmap, drawto_mm, gx, gy, MINI_TILEX, MINI_TILEY,
 		 dest_x, dest_y);
     else
-      ClearRectangle(drawto, dest_x, dest_y, MINI_TILEX, MINI_TILEY);
+      ClearRectangle(drawto_mm, dest_x, dest_y, MINI_TILEX, MINI_TILEY);
   }
 
   MarkTileDirty(x, y);
@@ -488,7 +495,7 @@ void DrawWallsAnimation_MM(int x, int y, int element, int phase, int bit_mask)
       getSizedGraphicSource(graphic, frame, MINI_TILESIZE, &bitmap,
 			    &src_x, &src_y);
 
-      BlitBitmap(bitmap, drawto, src_x, src_y, MINI_TILEX, MINI_TILEY,
+      BlitBitmap(bitmap, drawto_mm, src_x, src_y, MINI_TILEX, MINI_TILEY,
 		 dst_x, dst_y);
     }
   }
@@ -1243,6 +1250,6 @@ void RedrawPlayfield_MM(void)
 
 void BlitScreenToBitmap_MM(Bitmap *target_bitmap)
 {
-  BlitBitmap(drawto_field, target_bitmap,
+  BlitBitmap(drawto_mm, target_bitmap,
 	     REAL_SX, REAL_SY, FULL_SXSIZE, FULL_SYSIZE, REAL_SX, REAL_SY);
 }
diff --git a/src/game_mm/mm_tools.h b/src/game_mm/mm_tools.h
index f226f420..5f116c90 100644
--- a/src/game_mm/mm_tools.h
+++ b/src/game_mm/mm_tools.h
@@ -50,7 +50,8 @@
 
 
 void SetDrawtoField_MM(int);
-void BackToFront(void);
+void BackToFront_MM(void);
+
 void FadeToFront(void);
 void ClearWindow(void);
 
diff --git a/src/init.c b/src/init.c
index aae262f5..718e1ca2 100644
--- a/src/init.c
+++ b/src/init.c
@@ -5713,6 +5713,7 @@ void InitGfxBuffers(void)
 
   InitGfxBuffers_EM();
   InitGfxBuffers_SP();
+  InitGfxBuffers_MM();
 }
 
 static void InitGfx(void)
diff --git a/src/tools.c b/src/tools.c
index 124cab52..45447912 100644
--- a/src/tools.c
+++ b/src/tools.c
@@ -3008,19 +3008,6 @@ void ShowEnvelope(int envelope_nr)
   BackToFront();
 }
 
-void ShowEnvelope_MM(int envelope_nr)
-{
-  BlitBitmap(backbuffer, bitmap_db_field, REAL_SX, REAL_SY,
-	     FULL_SXSIZE, FULL_SYSIZE, REAL_SX, REAL_SY);
-
-  ShowEnvelope(envelope_nr);
-
-  SetDrawtoField(DRAW_TO_BACKBUFFER);
-
-  BlitBitmap(bitmap_db_field, backbuffer, REAL_SX, REAL_SY,
-	     FULL_SXSIZE, FULL_SYSIZE, REAL_SX, REAL_SY);
-}
-
 static void PrepareEnvelopeRequestToScreen(Bitmap *bitmap, int sx, int sy,
 					   int xsize, int ysize)
 {