Fixed 4669 - Using the software SDL_Renderer on Android leads to GL errors & black screen when window resizes

Sylvain

I think what happening with the software renderer is:

* you're somehow in background (so texture creation is not possible)
* it resizes and wants to push a SDL_WINDOWEVENT_SIZE_CHANGED
It call:
https://hg.libsdl.org/SDL/file/a010811d40dd/src/render/SDL_render.c#l683
* GetOutputSize
* SW_GetOutputSize
* SW_ActivateRenderer
* SDL_GetWindowSurface
* SDL_CreateWindowFramebuffer which is mapped to SDL_CreateWindowTexture
and it ends up re-creating the surface/a texture, while being in background

src/render/software/SDL_render_sw.c

@@ -82,20 +82,25 @@ SW_WindowEvent(SDL_Renderer * renderer, const SDL_WindowEvent *event)
 static int
 SW_GetOutputSize(SDL_Renderer * renderer, int *w, int *h)
 {
-    SDL_Surface *surface = SW_ActivateRenderer(renderer);
+    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
 
-    if (surface) {
+    if (data->surface) {
         if (w) {
-            *w = surface->w;
+            *w = data->surface->w;
         }
         if (h) {
-            *h = surface->h;
+            *h = data->surface->h;
         }
         return 0;
-    } else {
-        SDL_SetError("Software renderer doesn't have an output surface");
-        return -1;
     }
+
+    if (renderer->window) {
+        SDL_GetWindowSize(renderer->window, w, h);
+        return 0;
+    }
+
+    SDL_SetError("Software renderer doesn't have an output surface");
+    return -1;
 }
 
 static int
@@ -179,7 +184,7 @@ SW_SetRenderTarget(SDL_Renderer * renderer, SDL_Texture * texture)
 {
     SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
 
-    if (texture ) {
+    if (texture) {
         data->surface = (SDL_Surface *) texture->driverdata;
     } else {
         data->surface = data->window;