1:1 实现 UI 设计师使用 Sketch 时候更为喜欢的 平滑圆角 的绘制算法，自定义 View | Layout | Drawable 需提取绘制函数重写绘制方法
An android project explained how to draw Sketch's smooth corner in Android Canvas.
You can customize drawing function in your custom view n' achieve cool animation effect.
Also you can try it in this web demo —— compare uploaded image with effect in Web Canvas
See in release page
If the round radius is bigger than 90% of the shortest edge ,there will be tiny difference between real value in Sketch and the output value in Andoird (But in that case,I would use Round Corners)
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