WPF OpacityMask weird behavior
问题 I think I might have found a bug in WPF, or maybe I just don't fully understand how OpacityMasks work. As you can see on the first image, I have a diamond shaped path and a red circle. My goal is to make everything outside the diamond invisible. It works when the circle is inside the diamond shape, but whenever I move it to one of the corners, or outside the path, the OpacityMask seems to get stretched or distorted as you can see on the second image. My question is how can I make the