Register a callback to be fired whenever an orientation occurs that the app must respond to.
GLVIEW_API int glview_register_resize_callback(resize_callback resize_callback)
The callback to be fired on a resize event. If this parameter is NULL then any previously set callback is disabled.
Calling glview_register_resize_callback with a NULL resize_callback will prevent any previously set callback from being fired on a resize event. Any resize callback will never be fired if the app is set to landscape or portrait only.