Add two classes CombinedGeometry and PathGeometry just like WPF

[huangfuhao]

1.Add Two Classes CombinedGeometry ,PathGeometry just like WPF
2.Support one Method Combine

public static PathGeometry Combine(Geometry geometry1, Geometry geometry2, GeometryCombineMode mode, Transform transform, double tolerance, ToleranceType type)
{
            return PathGeometry.InternalCombine(geometry1, geometry2, mode, transform, tolerance, type);
 }

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[jeromelaban]

Thanks for the suggestion!

At this time, we cannot add this particular class because it is not supported by WinUI, mainly because the Clip Property is a RectangleGeometry. That being said, on Windows (and only Skia on Uno Platform at this time), it's possible to use the composition API to do visual clipping with CompositionGeometricClip.

[huangfuhao]

Well, thank you，i will try it,
Thank you for your contribution!