GUILayoutUtility.GetLastRect
static function GetLastRect(): Rect;
Returns
Rect The last used rectangle.
Description

Get the rectangle last used by GUILayout for a control.

Note that this only works during the Repaint event.
	function OnGUI() {
		GUILayout.Button( "My button" );
		if(Event.current.type == EventType.Repaint && 
		   GUILayoutUtility.GetLastRect().Contains(Event.current.mousePosition )) {
			GUILayout.Label( "Mouse over!" );
		} else {
			GUILayout.Label( "Mouse somewhere else" );
		}
	}