Exactly preserve the polyhedron boundary?

[evouga]

We are trying to tetrahedralize a parallelopiped, but find that the boundary triangles of the tetrahedralization are not exactly parallel to the input parallelopiped.

Is there a way to constrain TetWild to exactly preserve the input mesh (so that all vertices of the input mesh are present in the output; and also all Steiner points added on the boundary are exactly on an input face)?

[danielepanozzo]

Unfortunately not yet. We are working on an extension to support this, but it is a few months away. CGAL should be able to do exactly what you need, and you can try to call it from https://pymesh.readthedocs.io/en/latest/api_mesh_generation.html . @qnzhou wrote a nice wrapper for multiple tetrahedralization engines, and both CGAL and tetgen should be able to do this reliably if the boundary is a simple parallelopiped.