SDL_GL_GetDrawableSize

Get the size of a window's underlying drawable in pixels.

Header File

void SDL_GL_GetDrawableSize(SDL_Window * window, int *w,
                            int *h);

SDL_Window *	window	the window from which the drawable size should be queried.
int *	w	a pointer to variable for storing the width in pixels, may be NULL.
int *	h	a pointer to variable for storing the height in pixels, may be NULL.

This returns info useful for calling glViewport().

This may differ from SDL_GetWindowSize() if we're rendering to a high-DPI drawable, i.e. the window was created with SDL_WINDOW_ALLOW_HIGHDPI on a platform with high-DPI support (Apple calls this "Retina"), and not disabled by the SDL_HINT_VIDEO_HIGHDPI_DISABLED hint.

This function is available since SDL 2.0.1.