How to judge whether the order of 2 groups of points in 3D space has changed in space?

这个问题困惑了我好久–就是如何判断表面是否闭合, 尝试过一些方法都不理想, 后来我发现生成的点云的顺序在闭合时,按一定方向(这里是顺时针)规律排布, 而非闭合时, 其空间顺序发生了改变, 所以就有了上面👆🏻这个问题

This question has puzzled me for a long time - how to judge whether the surface is closed…I have tried some methods, but none of them are ideal.Later, I found that the order of the generated point clouds is arranged in a certain direction (clockwise here) when it is closed, but when it is not closed, its spatial order has changed, so there is the above problem :point_up_2:t2:.
How to extract the vertex coordinates of a polygon of a model in the current section?
How to judge a curve model obtained with vtkplanecut or vtkcutter is closed?