Methods A four-step procedure was adopted to configure the coarse mesh. The method of longest edge propagation path and the edge collapse were used to refine and optimize the final mesh.

• 方法采用四步剖分法得到初始网格并用最长边繁衍路径(longest edge propagation path)与棱边收缩(edge collapse)的方法进行网格的细分与优化。