如何通过UWP中的路径几何进行裁剪?

I want to clip a Grid by a dynamic PathGeometry and it's PathFigure. In WPF application UIElement.Clip has some properties like CombinedGeometry,PathGeometry ... But in UWP there's only RectangleGeometry. I'm very new to .Net and stuck on this right now, does anyone know the equivalent way in UWP? Thanks.I want to clip a Grid by a dynamic PathGeometry