Best pixel formats with alpha search code has been added to function which...

Best pixel formats with alpha search code has been added to function which converts surface to texture with enabled color keys. Now "testsprite2 --renderer opengl_es" works fine with all pixel formats with alpha. This affects other renderers too.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%403623

src/video/SDL_video.c

@@ -48,7 +48,7 @@
 #endif /* SDL_VIDEO_OPENGL */
 
 /* Available video drivers */
-static const VideoBootStrap *const bootstrap[] = {
+static VideoBootStrap *bootstrap[] = {
 #if SDL_VIDEO_DRIVER_COCOA
     &COCOA_bootstrap,
 #endif
@@ -1598,6 +1598,7 @@ SDL_CreateTextureFromSurface(Uint32 format, SDL_Surface * surface)
     SDL_TextureID textureID;
     Uint32 requested_format = format;
     SDL_PixelFormat *fmt;
+    SDL_Renderer *renderer;
     int bpp;
     Uint32 Rmask, Gmask, Bmask, Amask;
 
@@ -1607,6 +1608,11 @@ SDL_CreateTextureFromSurface(Uint32 format, SDL_Surface * surface)
     }
     fmt = surface->format;
 
+    renderer = SDL_CurrentDisplay.current_renderer;
+    if (!renderer) {
+        return 0;
+    }
+
     if (format) {
         if (!SDL_PixelFormatEnumToMasks
             (format, &bpp, &Rmask, &Gmask, &Bmask, &Amask)) {
@@ -1625,12 +1631,89 @@ SDL_CreateTextureFromSurface(Uint32 format, SDL_Surface * surface)
             Amask = fmt->Amask;
         } else {
             /* Need a format with alpha */
+            int it;
+            int apfmt;
+
+            /* Pixel formats with alpha, sorted by best first */
+            static const Uint32 sdl_alpha_pformats[]={
+               SDL_PIXELFORMAT_ARGB8888,
+               SDL_PIXELFORMAT_RGBA8888,
+               SDL_PIXELFORMAT_ABGR8888,
+               SDL_PIXELFORMAT_BGRA8888,
+               SDL_PIXELFORMAT_ARGB1555,
+               SDL_PIXELFORMAT_ABGR1555,
+               SDL_PIXELFORMAT_ARGB4444,
+               SDL_PIXELFORMAT_ABGR4444,
+               SDL_PIXELFORMAT_ARGB2101010,
+               SDL_PIXELFORMAT_UNKNOWN};
+
             bpp = 32;
             Rmask = 0x00FF0000;
             Gmask = 0x0000FF00;
             Bmask = 0x000000FF;
             Amask = 0xFF000000;
+
+            format = SDL_MasksToPixelFormatEnum(bpp, Rmask, Gmask, Bmask, Amask);
+            if (!format) {
+                SDL_SetError("Unknown pixel format");
+                return 0;
+            }
+
+            /* Search this format in the supported texture formats */
+            /* by current renderer                                 */
+            for (it=0; it<renderer->info.num_texture_formats; it++)
+            {
+                if (renderer->info.texture_formats[it]==format)
+                {
+                   break;
+                }
+            }
+
+            /* If this format can't be found, search any best       */
+            /* compatible format with alpha which renderer provides */
+            if (it==renderer->info.num_texture_formats)
+            {
+                apfmt=0;
+                for (;;)
+                {
+                    if (sdl_alpha_pformats[apfmt]==SDL_PIXELFORMAT_UNKNOWN)
+                    {
+                        break;
                     }
+
+                    for (it=0; it<renderer->info.num_texture_formats; it++)
+                    {
+                       if (renderer->info.texture_formats[it]==sdl_alpha_pformats[apfmt])
+                       {
+                          break;
+                       }
+                    }
+
+                    if (it!=renderer->info.num_texture_formats)
+                    {
+                       /* Compatible format has been found */
+                       break;
+                    }
+                    apfmt++;
+                }
+
+                /* If compatible format can't be found, then return an error */
+                if (it==renderer->info.num_texture_formats)
+                {
+                    SDL_SetError("Compatible pixel format can't be found");
+                    return 0;
+                }
+
+                /* Convert found pixel format back to color masks */
+                if (SDL_PixelFormatEnumToMasks(renderer->info.texture_formats[it],
+                       &bpp, &Rmask, &Gmask, &Bmask, &Amask)!=SDL_TRUE)
+                {
+                    SDL_SetError("Unknown pixel format");
+                    return 0;
+                }
+            }
+        }
+
         format = SDL_MasksToPixelFormatEnum(bpp, Rmask, Gmask, Bmask, Amask);
         if (!format) {
             SDL_SetError("Unknown pixel format");