public MyTopWindowBridgeOpenGL(RootGraphic root, ITopWindowEventRoot topWinEventRoot)
: base(root, topWinEventRoot)
{
GlobalRootGraphic.CurrentRootGfx = root;
_rootgfx = root;
_defaultCur = UIPlatform.CreateCursor(new CursorRequest("system:Default"));
_IBeamCur = UIPlatform.CreateCursor(new CursorRequest("system:IBeam"));
_pointerCur = UIPlatform.CreateCursor(new CursorRequest("system:Pointer"));
_arrowCur = UIPlatform.CreateCursor(new CursorRequest("system:Arrow"));
}