什么叫"非歧异实体"啊?是指Non-Manifold Solid吧
Manifold 是个拓朴学名词,A manifold is a topological space that is locally Euclidean (i.e., around every point, there is a neighborhood that is topologically the same as the open unit ball in ). ....简单说就Manifold就是一个连通域。一块泥巴揉成个团,随你怎么捏,只要不捏破泥巴的表面,一个鱼圆,一个大饼,一块巧克力,它都是在同一种连通域中。你把泥巴团一切二,两边不联通了,就叫Non-Manifold乐