Currently, the SDL_WINDOWEVENT_RESIZED event is sent before the actual
window is resized (and various internal state, such as the desired
GL/Vulkan backbuffer size, are updated). This makes sense, as SDL will
discard a no-op resize, which would be the case if we had resized before
sending the event (indeed, there are existing hacks to prevent this).
However, this means that SDL_{GL,Vulkan}_GetDrawableSize() will still
use the old size in the SDL_WINDOWEVENT_RESIZED handler. In the case of
SDL_Renderer, this means the drawable size it uses will be wrong, and
the viewport will get "updated" to the old value.
This then results in bug #5899.
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
More extensive documentation is available in the docs directory, starting
with README.md
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