the window to query the size values of the border (decorations) from.
pointer to variable for storing the size of the top border; NULL is permitted.
pointer to variable for storing the size of the left border; NULL is permitted.
pointer to variable for storing the size of the bottom border; NULL is permitted.
pointer to variable for storing the size of the right border; NULL is permitted.
true on success or false on failure; call SDL_GetError() for more information.
Threadsafety: This function should only be called on the main thread.
Get the size of a window's borders (decorations) around the client area.
Note: If this function fails (returns false), the size values will be initialized to 0, 0, 0, 0 (if a non-NULL pointer is provided), as if the window in question was borderless.
Note: This function may fail on systems where the window has not yet been decorated by the display server (for example, immediately after calling SDL_CreateWindow). It is recommended that you wait at least until the window has been presented and composited, so that the window system has a chance to decorate the window and provide the border dimensions to SDL.
This function also returns false if getting the information is not supported.