Set Renderer.readPixels alpha channel to be non-transparent on native targets

project/src/backend/sdl/SDLRenderer.cpp

@@ -217,6 +217,10 @@ namespace lime {
 			
 			SDL_RenderReadPixels (sdlRenderer, &bounds, SDL_PIXELFORMAT_ABGR8888, buffer->data->Data (), buffer->Stride ());
 			
+			for (unsigned char *it=buffer->data->Data()+3; it<(buffer->data->Data()+buffer->data->Length());it+=4) {
+				*it = 0xff;
+			}
+
 		}
 		
 	}