Fixing non-simple polygons - untying bow tie topology
In working on Mapfile.dll, in order to get the points/faces of each brush, I get
the 3-plane intersection of every plane in the bounding area (removing illegal
points). This gives me a set of points associated with each face. Faces can be
polygons of any order n (triangles, quads, pentagons, octagons, etc.) so long as
they are convex. However, I came to a problem: after resolving the plane
intersections into sets…