Fixed bug 2122 - SDL_CreateTexture allows illegal texture sizes

Lloyd Bryant

SDL_CreateTexture() is succeeding (i.e. returning a valid pointer) when the requested horizontal or vertical size of the texture exceeds the maximum allowed by the render.  This results in hard-to-understand errors showing up when later attempting to use that texture (such as with SDL_SetRenderTarget()).

src/render/SDL_render.c

@@ -410,6 +410,11 @@ SDL_CreateTexture(SDL_Renderer * renderer, Uint32 format, int access, int w, int
         SDL_SetError("Texture dimensions can't be 0");
         return NULL;
     }
+    if ((renderer->info.max_texture_width && w > renderer->info.max_texture_width) ||
+        (renderer->info.max_texture_height && h > renderer->info.max_texture_height)) {
+        SDL_SetError("Texture dimensions are limited to %dx%d", renderer->info.max_texture_width, renderer->info.max_texture_height);
+        return NULL;
+    }
     texture = (SDL_Texture *) SDL_calloc(1, sizeof(*texture));
     if (!texture) {
         SDL_OutOfMemory();

src/render/opengles2/SDL_render_gles2.c

@@ -1627,6 +1627,7 @@ GLES2_CreateRenderer(SDL_Window *window, Uint32 flags)
 #endif
     Uint32 windowFlags;
     GLint window_framebuffer;
+    GLint value;
 
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
@@ -1685,6 +1686,13 @@ GLES2_CreateRenderer(SDL_Window *window, Uint32 flags)
         renderer->info.flags |= SDL_RENDERER_PRESENTVSYNC;
     }
 
+    value = 0;
+    rdata->glGetIntegerv(GL_MAX_TEXTURE_SIZE, &value);
+    renderer->info.max_texture_width = value;
+    value = 0;
+    rdata->glGetIntegerv(GL_MAX_TEXTURE_SIZE, &value);
+    renderer->info.max_texture_height = value;
+
     /* Determine supported shader formats */
     /* HACK: glGetInteger is broken on the Zune HD's compositor, so we just hardcode this */
     rdata->glGetError();