render: SDL_RenderPresent now behaves when a render target is currently set.

It'll temporarily unbind it, draw letterboxing if necessary, present, and
then rebind the previous render target.
This commit is contained in:
Ryan C. Gordon 2024-09-25 12:33:21 -04:00
parent 7a6a0becb8
commit 4c48ff51f8
2 changed files with 13 additions and 7 deletions

View file

@ -2061,10 +2061,12 @@ extern SDL_DECLSPEC SDL_Surface * SDLCALL SDL_RenderReadPixels(SDL_Renderer *ren
* pixel.
*
* Please note, that in case of rendering to a texture - there is **no need**
* to call `SDL_RenderPresent` after drawing needed objects to a texture, you
* are only required to change back the rendering target to default via
* `SDL_SetRenderTarget(renderer, NULL)` afterwards, as textures by themselves
* do not have a concept of backbuffers.
* to call `SDL_RenderPresent` after drawing needed objects to a texture, and
* should not be done; you are only required to change back the rendering
* target to default via `SDL_SetRenderTarget(renderer, NULL)` afterwards, as
* textures by themselves do not have a concept of backbuffers. Calling
* SDL_RenderPresent while rendering to a texture will still update the
* screen with any current drawing that has been done _to the window itself_.
*
* \param renderer the rendering context.
* \returns true on success or false on failure; call SDL_GetError() for more

View file

@ -4949,9 +4949,9 @@ bool SDL_RenderPresent(SDL_Renderer *renderer)
CHECK_RENDERER_MAGIC(renderer, false);
// !!! FIXME: fail if using a render target? Or just implicitly set the render target to NULL now?
if (renderer->view != &renderer->main_view) {
return SDL_SetError("Cannot present a render target");
SDL_Texture *target = renderer->target;
if (target) {
SDL_SetRenderTarget(renderer, NULL);
}
SDL_RenderLogicalPresentation(renderer);
@ -4972,6 +4972,10 @@ bool SDL_RenderPresent(SDL_Renderer *renderer)
presented = false;
}
if (target) {
SDL_SetRenderTarget(renderer, target);
}
if (renderer->simulate_vsync ||
(!presented && renderer->wanted_vsync)) {
SDL_SimulateRenderVSync(renderer);