多边形填充方法很多，但效率大不相同，这是我写的一种方法，首先多边形分解为三角形，然后填充三角形，很实用，效率也可以，调试已通过，没有错误-Polygon filling method, but the efficiency of very different, this is a way I write, the first polygon is decomposed into triangles, and then fill the triangle, it is practical, eff