Huh, I'll look at tetgen v. 1.5 and ctetgen (right now, the cluster where I'm having some problems is offline). In theory, I could try to do the triangulation with CGAL <http://www.cgal.org>, which I'm already using to find the intersections ... but its triangulation construction is quite a bit more complex and expensive to set up than tetgen and co.
On 26/09/16 16:22, John Peterson wrote: > > > On Sat, Sep 24, 2016 at 9:19 AM, Thiago Milanetto Schlittler > <thiago...@gmail.com <mailto:thiago...@gmail.com>> wrote: > > Hello! > > I'm having a weird problem with the method > "triangulate_pointset()", > from the TetGenMeshInterface class. Essentially, it seems like it is > stalling after several calls. In my code, I have to calculate several > polyhedron intersections and mesh them. To do so, I built a > Mesh_Intersection class, which has the following method: > > void Mesh_Intersection::triangulate_intersection(const > std::set<libMesh::Point> & input_points) > { > /* > * input_points : set containing the intersection > * polyhedron's vertices. > * m_libMesh_PolyhedronMesh : a libMesh::Mesh, member of the > Mesh_Intersection > * cleared when calling this method. > */ > > m_libMesh_PolyhedronMesh.clear(); > > // Insert points into the mesh > for(std::set<libMesh::Point>::const_iterator it_set = > input_points.begin(); > it_set != input_points.end(); > ++it_set) > { > m_libMesh_PolyhedronMesh.add_point(*it_set); > } > > libMesh::TetGenMeshInterface > temp_tetgen_interface(m_libMesh_PolyhedronMesh); > temp_tetgen_interface.triangulate_pointset(); > } > > The code stalls at the last line. I already tested the > input_points, > and they are valid. I'm using libMesh 1.0.0, compiled with Intel > icpc v. > 16.0.3 and Intel MPI v. 5.1.2, on Linux. The > m_libMesh_PolyhedronMesh is > associated to a single processor. I don't think that it is a > communicator problem because it happens even with only one > processor. I > think that the problem is associated to the compiler, since it works > well on a machine where I used gcc 4.9. Did anyone else have a similar > problem? > > > Yes, I have seen tetgen go into an infinite loop before, but due to > the complexity of the Tetgen codebase, was not really able to > determine why at the time. If I recall correctly, the problem was > also architecture/compiler dependent, and the mesh generation problem > itself was not complicated, i.e. just looking at the geometry, you > would not think that mesh generation would be an issue. I tried > searching back through my email for some thread that would have more > information on this, but could not find anything... > > If tetgen is important to your application, you may want to try > updating it. We are still apparently using version 1.4.1 from back in > 2006, but there is a version 1.5 available from the tetgen.org > <http://tetgen.org> website. Another possibility you might want to > investigate is the PETSc team's C-based rewrite of Tetgen, called > ctetgen (https://bitbucket.org/petsc/ctetgen > <https://bitbucket.org/petsc/ctetgen>). I get a ton of warnings when > compiling Tetgen, and get the impression that it is not the cleanest > piece of code ever... if the PETSc guys decided to entirely rewrite it > and maintain a forked version, they probably had a compelling reason > to do so. I would definitely be willing to switch to ctetgen (we'll > probably have to update some of our interface code slightly to do so) > but don't really have time to work on that myself. > > -- > John ------------------------------------------------------------------------------ _______________________________________________ Libmesh-users mailing list Libmesh-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-users
