It seems several people use tetgen here, and I was wondering if anyone could help me out.
I've created a tetrahedron mesh using a set of vertices from a .node file. However, there are some parts on the boundary of the mesh that should be concave. I tried to specify those nodes using the boundary marker 1, but the mesh tetgen creates still surrounds those nodes (i.e. node 8 below). Why doesn't this work?
Here's a really simple example of my .node file:
#test.node
9 3 0 1
0 0 0 0 1
1 1 0 0 1
2 1 1 0 1
3 0 1 0 1
4 0 0 1 1
5 1 0 1 1
6 1 1 1 1
7 0 1 1 1
8 0.3 0.5 0.5 1