Allow the application to draw while Windows is in a modal move/resize loop

SDL will send an SDL_EVENT_WINDOW_EXPOSED event for your window during the modal interaction and you can use an event watcher to redraw your window directly from the callback.

Fixes https://github.com/libsdl-org/SDL/issues/1059
Closes https://github.com/libsdl-org/SDL/pull/4836
This commit is contained in:
Sam Lantinga
2023-11-08 14:01:00 -08:00
parent 3900fca304
commit 509c70c698
2 changed files with 52 additions and 7 deletions

View File

@@ -392,22 +392,30 @@ void MoveSprites(SDL_Renderer *renderer, SDL_Texture *sprite)
SDL_RenderPresent(renderer);
}
void loop()
static void MoveAllSprites()
{
Uint32 now;
int i;
SDL_Event event;
/* Check for events */
while (SDL_PollEvent(&event)) {
SDLTest_CommonEvent(state, &event, &done);
}
for (i = 0; i < state->num_windows; ++i) {
if (state->windows[i] == NULL) {
continue;
}
MoveSprites(state->renderers[i], sprites[i]);
}
}
void loop()
{
Uint32 now;
SDL_Event event;
/* Check for events */
while (SDL_PollEvent(&event)) {
SDLTest_CommonEvent(state, &event, &done);
}
MoveAllSprites();
#ifdef __EMSCRIPTEN__
if (done) {
emscripten_cancel_main_loop();
@@ -426,6 +434,14 @@ void loop()
}
}
static int SDLCALL ExposeEventWatcher(void *userdata, SDL_Event *event)
{
if (event->type == SDL_WINDOWEVENT && event->window.event == SDL_WINDOWEVENT_EXPOSED) {
MoveAllSprites();
}
return 0;
}
int main(int argc, char *argv[])
{
int i;
@@ -568,6 +584,9 @@ int main(int argc, char *argv[])
}
}
/* Add an event watcher to redraw from within modal window resize/move loops */
SDL_AddEventWatch(ExposeEventWatcher, NULL);
/* Main render loop */
frames = 0;
next_fps_check = SDL_GetTicks() + fps_check_delay;