Dear SDL team,

when my app left the SDL_WINDOW_FULLSCREEN mode in Windows 10 and switched back to a normal smaller window, it received a resize event to blow the normal window back up to the fullscreen resolution.

I traced it back and found that..

1) My app calls SDL_DestroyWindow when leaving fullscreen.
2) SDL_DestroyWindow calls SDL_HideWindow
3) SDL_HideWindow calls SDL_UpdateFullscreenMode(window, SDL_FALSE);
4) SDL_UpdateFullscreenMode calls SDL_OnWindowResized(window);
5) SDL_OnWindowResized sends the unexpected SDL_WINDOWEVENT_SIZE_CHANGED

I figured it is not really expected to send a SDL_WINDOWEVENT_SIZE_CHANGED event with the old window size when you want to hide a window (but maybe there is a good reason ;-), anyway I patched it away like this


>replace

SDL_OnWindowResized(SDL_Window * window)
{
    window->surface_valid = SDL_FALSE;
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_SIZE_CHANGED, window->w, window->h);
}

>with

SDL_OnWindowResized(SDL_Window * window)
{
    window->surface_valid = SDL_FALSE;
    /* Do not generate a size change event if we are hiding the window, e.g. during SDL_DestroyWindow,
       otherwise the App will receive a resize event for the next window opened with the old size */
    if (!window->is_hiding) SDL_SendWindowEvent(window, SDL_WINDOWEVENT_SIZE_CHANGED, window->w, window->h);
}


This may be related to bug 4760:
https://bugzilla.libsdl.org/show_bug.cgi?id=4760

It also persists in the latest SDL 2.0.12.

Best regards,
Elmar