Dear all,
I am a bit confused. Imagine I would like to create a polygonal triangulation of the sphere looking something like the image below:
The mesher in fenics seems to create some sort of Delauney triangulation, which is not really what I want. Is there a detailed description somewhere about how “generate_mesh” works?
Hi,
As stated in the README.md at mshr:
mshr is the mesh generation component of FEniCS. It generates simplicial DOLFIN meshes in 2D and 3D from geometries described by Constructive Solid Geometry (CSG) or from surface files, utilizing CGAL and Tetgen as mesh generation backends.
Therefore, I suggest looking into these two backends for details.
You could consider using external meshing software, such as gmsh to generate the meshes, and meshio to transfer the meshes to a readable format for FEniCS, see Transitioning from mesh.xml to mesh.xdmf, from dolfin-convert to meshio for a detailed description of how to do this transformation.
so there is no way to generate a “uniform” mesh in FEniCS with equilateral-ish triangles?
Well, there probably is, but the mshr documentation is quite sparse.
There seem to be several triangulation methods, see:
https://bitbucket.org/fenics-project/mshr/src/master/3rdparty/CGAL/examples/Triangulation/
and
https://bitbucket.org/fenics-project/mshr/src/master/3rdparty/CGAL/demo/
Thank you for your reply. I have to say, the mshr documentation is VERY sparse. How do I access these functions in python, even? Any tips?
That’s a very good question I don’t have an answer for. I would suggest using other software, such as the gmsh->pygmsh->meshio pipeline. You can also consider creating an issue on mshr’s bitbucket page: https://bitbucket.org/fenics-project/mshr/issues
as its more likely that the developers read whats happening there.