implicit-surface

问题 I render isosurfaces with marching cubes, (or perhaps marching squares as this is 2D) and I want to do set operations like set difference, intersection and union. I thought this was easy to implement, by simply choosing between two vertex scalars from two different implicit surfaces, but it is not. For my initial testing, I tried with two spheres circles, and the set operation difference . i.e A - B. One circle is moving and the other one is stationary. Here's the approach I tried when

问题 I've been using one of the older implicit surface algorithms, due to Bloomenthal, as found here, basically the tetrahedral-based algorithm. This works fairly well, but has a shortcoming. Since it uses a fixed grid, it either wastes polygons or ignores detail, depending on the grid size selected. So my question is, what are my options for improving this? Are there any freely available (source or good description) implicit surface algorithms which are more adaptive to the curvature of the model