changed loading images to use function for creating opaque surface
[rocksndiamonds.git] / src / libgame / sdl.c
index 48a3e374ec39f5a64796bee38fb02b072137ca9a..f805ddfd6c1ef5a213a805026bd935648478aea1 100644 (file)
@@ -223,34 +223,40 @@ static boolean equalSDLPixelFormat(SDL_PixelFormat *format1,
          format1->BytesPerPixel == format2->BytesPerPixel &&
          format1->Rmask         == format2->Rmask &&
          format1->Gmask         == format2->Gmask &&
-         format1->Bmask         == format2->Bmask &&
-         format1->Amask         == format2->Amask);
+         format1->Bmask         == format2->Bmask);
 }
 
-boolean SDLSetNativeSurface(SDL_Surface **surface)
+static Pixel SDLGetColorKey(SDL_Surface *surface)
 {
-  SDL_Surface *new_surface;
+  Pixel color_key;
 
-  if (surface == NULL ||
-      *surface == NULL ||
-      backbuffer == NULL ||
-      backbuffer->surface == NULL)
-    return FALSE;
+  if (SDL_GetColorKey(surface, &color_key) != 0)
+    return -1;
 
-  // if pixel format already optimized for destination surface, do nothing
-  if (equalSDLPixelFormat((*surface)->format, backbuffer->surface->format))
-    return FALSE;
+  return color_key;
+}
 
-  new_surface = SDL_ConvertSurface(*surface, backbuffer->surface->format, 0);
+static boolean SDLHasColorKey(SDL_Surface *surface)
+{
+  return (SDLGetColorKey(surface) != -1);
+}
 
-  if (new_surface == NULL)
-    Error(ERR_EXIT, "SDL_ConvertSurface() failed: %s", SDL_GetError());
+static boolean SDLHasAlpha(SDL_Surface *surface)
+{
+  SDL_BlendMode blend_mode;
 
-  SDL_FreeSurface(*surface);
+  if (SDL_GetSurfaceBlendMode(surface, &blend_mode) != 0)
+    return FALSE;
 
-  *surface = new_surface;
+  return (blend_mode == SDL_BLENDMODE_BLEND);
+}
 
-  return TRUE;
+static void SDLSetAlpha(SDL_Surface *surface, boolean set, int alpha)
+{
+  SDL_BlendMode blend_mode = (set ? SDL_BLENDMODE_BLEND : SDL_BLENDMODE_NONE);
+
+  SDL_SetSurfaceBlendMode(surface, blend_mode);
+  SDL_SetSurfaceAlphaMod(surface, alpha);
 }
 
 SDL_Surface *SDLGetNativeSurface(SDL_Surface *surface)
@@ -279,21 +285,21 @@ SDL_Surface *SDLGetNativeSurface(SDL_Surface *surface)
   return new_surface;
 }
 
-#else
-
 boolean SDLSetNativeSurface(SDL_Surface **surface)
 {
   SDL_Surface *new_surface;
 
   if (surface == NULL ||
       *surface == NULL ||
-      !video.initialized)
+      backbuffer == NULL ||
+      backbuffer->surface == NULL)
     return FALSE;
 
-  new_surface = SDL_DisplayFormat(*surface);
+  // if pixel format already optimized for destination surface, do nothing
+  if (equalSDLPixelFormat((*surface)->format, backbuffer->surface->format))
+    return FALSE;
 
-  if (new_surface == NULL)
-    Error(ERR_EXIT, "SDL_DisplayFormat() failed: %s", SDL_GetError());
+  new_surface = SDLGetNativeSurface(*surface);
 
   SDL_FreeSurface(*surface);
 
@@ -302,14 +308,44 @@ boolean SDLSetNativeSurface(SDL_Surface **surface)
   return TRUE;
 }
 
+#else
+
+static Pixel SDLGetColorKey(SDL_Surface *surface)
+{
+  if ((surface->flags & SDL_SRCCOLORKEY) == 0)
+    return -1;
+
+  return surface->format->colorkey;
+}
+
+static boolean SDLHasColorKey(SDL_Surface *surface)
+{
+  return (SDLGetColorKey(surface) != -1);
+}
+
+static boolean SDLHasAlpha(SDL_Surface *surface)
+{
+  return ((surface->flags & SDL_SRCALPHA) != 0);
+}
+
+static void SDLSetAlpha(SDL_Surface *surface, boolean set, int alpha)
+{
+  SDL_SetAlpha(surface, (set ? SDL_SRCALPHA : 0), alpha);
+}
+
 SDL_Surface *SDLGetNativeSurface(SDL_Surface *surface)
 {
   SDL_Surface *new_surface;
 
-  if (video.initialized)
-    new_surface = SDL_DisplayFormat(surface);
-  else
+  if (surface == NULL)
+    return NULL;
+
+  if (!video.initialized)
     new_surface = SDL_ConvertSurface(surface, surface->format, SURFACE_FLAGS);
+  else if (SDLHasAlpha(surface))
+    new_surface = SDL_DisplayFormatAlpha(surface);
+  else
+    new_surface = SDL_DisplayFormat(surface);
 
   if (new_surface == NULL)
     Error(ERR_EXIT, "%s() failed: %s",
@@ -319,6 +355,24 @@ SDL_Surface *SDLGetNativeSurface(SDL_Surface *surface)
   return new_surface;
 }
 
+boolean SDLSetNativeSurface(SDL_Surface **surface)
+{
+  SDL_Surface *new_surface;
+
+  if (surface == NULL ||
+      *surface == NULL ||
+      !video.initialized)
+    return FALSE;
+
+  new_surface = SDLGetNativeSurface(*surface);
+
+  SDL_FreeSurface(*surface);
+
+  *surface = new_surface;
+
+  return TRUE;
+}
+
 #endif
 
 #if defined(TARGET_SDL2)
@@ -431,7 +485,7 @@ void SDLInitVideoBuffer(boolean fullscreen)
      should never be drawn to directly, it would do no harm nevertheless. */
 
   /* create additional (symbolic) buffer for double-buffering */
-  ReCreateBitmap(&window, video.width, video.height, video.depth);
+  ReCreateBitmap(&window, video.width, video.height);
 }
 
 static boolean SDLCreateScreen(boolean fullscreen)
@@ -924,7 +978,7 @@ void PrepareFadeBitmap(int draw_target)
   FinalizeScreen(draw_target);
 }
 
-void SDLFadeRectangle(Bitmap *bitmap_cross, int x, int y, int width, int height,
+void SDLFadeRectangle(int x, int y, int width, int height,
                      int fade_mode, int fade_delay, int post_delay,
                      void (*draw_border_function)(void))
 {
@@ -992,11 +1046,8 @@ void SDLFadeRectangle(Bitmap *bitmap_cross, int x, int y, int width, int height,
     int i;
 
     SDL_BlitSurface(surface_source, &src_rect, surface_screen, &dst_rect);
-#if defined(TARGET_SDL2)
-    SDL_SetSurfaceBlendMode(surface_target, SDL_BLENDMODE_NONE);
-#else
-    SDL_SetAlpha(surface_target, 0, 0);                /* disable alpha blending */
-#endif
+
+    SDLSetAlpha(surface_target, FALSE, 0);     /* disable alpha blending */
 
     ypos[0] = -GetSimpleRandom(16);
 
@@ -1109,11 +1160,8 @@ void SDLFadeRectangle(Bitmap *bitmap_cross, int x, int y, int width, int height,
     int xx_size = width / 2;
 
     SDL_BlitSurface(surface_target, &src_rect, surface_screen, &dst_rect);
-#if defined(TARGET_SDL2)
-    SDL_SetSurfaceBlendMode(surface_source, SDL_BLENDMODE_NONE);
-#else
-    SDL_SetAlpha(surface_source, 0, 0);                /* disable alpha blending */
-#endif
+
+    SDLSetAlpha(surface_source, FALSE, 0);     /* disable alpha blending */
 
     for (xx = 0; xx < xx_size;)
     {
@@ -1176,12 +1224,7 @@ void SDLFadeRectangle(Bitmap *bitmap_cross, int x, int y, int width, int height,
       SDL_BlitSurface(surface_source, &src_rect, surface_screen, &dst_rect);
 
       /* draw new (target) image to screen buffer using alpha blending */
-#if defined(TARGET_SDL2)
-      SDL_SetSurfaceAlphaMod(surface_target, alpha_final);
-      SDL_SetSurfaceBlendMode(surface_target, SDL_BLENDMODE_BLEND);
-#else
-      SDL_SetAlpha(surface_target, SDL_SRCALPHA, alpha_final);
-#endif
+      SDLSetAlpha(surface_target, TRUE, alpha_final);
       SDL_BlitSurface(surface_target, &src_rect, surface_screen, &dst_rect);
 
       if (draw_border_function != NULL)
@@ -2081,7 +2124,8 @@ SDL_Surface *zoomSurface(SDL_Surface *src, int dst_width, int dst_height)
   {
     /* new source surface is 32 bit with a defined RGB ordering */
     zoom_src = SDL_CreateRGBSurface(SURFACE_FLAGS, src->w, src->h, 32,
-                                   0x000000ff, 0x0000ff00, 0x00ff0000, 0);
+                                   0x000000ff, 0x0000ff00, 0x00ff0000,
+                                   (src->format->Amask ? 0xff000000 : 0));
     SDL_BlitSurface(src, NULL, zoom_src, NULL);
     is_32bit = TRUE;
     is_converted = TRUE;
@@ -2094,7 +2138,8 @@ SDL_Surface *zoomSurface(SDL_Surface *src, int dst_width, int dst_height)
     zoom_dst = SDL_CreateRGBSurface(SURFACE_FLAGS, dst_width, dst_height, 32,
                                    zoom_src->format->Rmask,
                                    zoom_src->format->Gmask,
-                                   zoom_src->format->Bmask, 0);
+                                   zoom_src->format->Bmask,
+                                   zoom_src->format->Amask);
   }
   else
   {
@@ -2135,10 +2180,30 @@ SDL_Surface *zoomSurface(SDL_Surface *src, int dst_width, int dst_height)
   return zoom_dst;
 }
 
+static SDL_Surface *SDLGetOpaqueSurface(SDL_Surface *surface)
+{
+  SDL_Surface *new_surface;
+
+  if (surface == NULL)
+    return NULL;
+
+  if ((new_surface = SDLGetNativeSurface(surface)) == NULL)
+    Error(ERR_EXIT, "SDLGetNativeSurface() failed");
+
+  /* remove alpha channel from native non-transparent surface, if defined */
+  SDLSetAlpha(new_surface, FALSE, 0);
+
+  /* remove transparent color from native non-transparent surface, if defined */
+  SDL_SetColorKey(new_surface, UNSET_TRANSPARENT_PIXEL, 0);
+
+  return new_surface;
+}
+
 Bitmap *SDLZoomBitmap(Bitmap *src_bitmap, int dst_width, int dst_height)
 {
   Bitmap *dst_bitmap = CreateBitmapStruct();
-  SDL_Surface **dst_surface = &dst_bitmap->surface;
+  SDL_Surface *src_surface = src_bitmap->surface_masked;
+  SDL_Surface *dst_surface;
 
   dst_width  = MAX(1, dst_width);      /* prevent zero bitmap width */
   dst_height = MAX(1, dst_height);     /* prevent zero bitmap height */
@@ -2147,10 +2212,21 @@ Bitmap *SDLZoomBitmap(Bitmap *src_bitmap, int dst_width, int dst_height)
   dst_bitmap->height = dst_height;
 
   /* create zoomed temporary surface from source surface */
-  *dst_surface = zoomSurface(src_bitmap->surface, dst_width, dst_height);
+  dst_surface = zoomSurface(src_surface, dst_width, dst_height);
 
   /* create native format destination surface from zoomed temporary surface */
-  SDLSetNativeSurface(dst_surface);
+  SDLSetNativeSurface(&dst_surface);
+
+  /* set color key for zoomed surface from source surface, if defined */
+  if (SDLHasColorKey(src_surface))
+    SDL_SetColorKey(dst_surface, SET_TRANSPARENT_PIXEL,
+                   SDLGetColorKey(src_surface));
+
+  /* create native non-transparent surface for opaque blitting */
+  dst_bitmap->surface = SDLGetOpaqueSurface(dst_surface);
+
+  /* set native transparent surface for masked blitting */
+  dst_bitmap->surface_masked = dst_surface;
 
   return dst_bitmap;
 }
@@ -2171,41 +2247,31 @@ Bitmap *SDLLoadImage(char *filename)
 
   /* load image to temporary surface */
   if ((sdl_image_tmp = IMG_Load(filename)) == NULL)
-  {
-    SetError("IMG_Load(): %s", SDL_GetError());
-
-    return NULL;
-  }
+    Error(ERR_EXIT, "IMG_Load() failed: %s", SDL_GetError());
 
   print_timestamp_time("IMG_Load");
 
   UPDATE_BUSY_STATE();
 
   /* create native non-transparent surface for current image */
-  if ((new_bitmap->surface = SDLGetNativeSurface(sdl_image_tmp)) == NULL)
-  {
-    SetError("SDL_DisplayFormat(): %s", SDL_GetError());
-
-    return NULL;
-  }
+  if ((new_bitmap->surface = SDLGetOpaqueSurface(sdl_image_tmp)) == NULL)
+    Error(ERR_EXIT, "SDLGetOpaqueSurface() failed");
 
-  print_timestamp_time("SDL_DisplayFormat (opaque)");
+  print_timestamp_time("SDLGetNativeSurface (opaque)");
 
   UPDATE_BUSY_STATE();
 
-  /* create native transparent surface for current image */
-  if (sdl_image_tmp->format->Amask == 0)
+  /* set black pixel to transparent if no alpha channel / transparent color */
+  if (!SDLHasAlpha(sdl_image_tmp) &&
+      !SDLHasColorKey(sdl_image_tmp))
     SDL_SetColorKey(sdl_image_tmp, SET_TRANSPARENT_PIXEL,
                    SDL_MapRGB(sdl_image_tmp->format, 0x00, 0x00, 0x00));
 
+  /* create native transparent surface for current image */
   if ((new_bitmap->surface_masked = SDLGetNativeSurface(sdl_image_tmp)) == NULL)
-  {
-    SetError("SDL_DisplayFormat(): %s", SDL_GetError());
-
-    return NULL;
-  }
+    Error(ERR_EXIT, "SDLGetNativeSurface() failed");
 
-  print_timestamp_time("SDL_DisplayFormat (masked)");
+  print_timestamp_time("SDLGetNativeSurface (masked)");
 
   UPDATE_BUSY_STATE();