Another method to creat Heptagon angel

I had mentioned a heptagon construction method which start from 3 times agnel. But I forgot to post how to set up this angel. here is the method.

前面的一篇博文提到的三倍角做法，过去没有贴上来，现在补贴。做法很简单，根据颜色提示依次画出单位方块，然后就是圆了。那些虚线圆是圆心位置，半径就是相同的颜色线段。