On 14/06/2025 18:45, Steven Dargaville wrote:
Hi, I'm just wondering if it is possible to generate a simple
unstructured mesh in 2D with DMPlex and one of the external generators,
like triangle?
I'm running snes/tutorials/ex20 which uses triangle and I can only seem
to generate structured triangular meshes. It is a simple 2D box so it
makes sense a Delaunay might output a structured mesh in that case. I
know I could get the DM to read in an unstructured mesh from a file that
I have previously generated, but for ease I'm wondering if this can be
done directly.
I've tried a few different things to try and force an unstructured mesh
being generated, like changing the number of faces to 1 (-
dm_plex_box_faces 1,1) so it only sees the corners of the box domain.
I've also tried to set some of the options to triangle with
DMPlexTriangleSetOptions but that doesn't seem to have any effect, so
I'm guessing I'm potentially not using it correctly (and I can't seem to
find any examples that use this function to help).
Anyone have any suggestions? Thanks for your help
I don't know how the mesh is generated, but a workaround would be to
generate a coarse mesh then use the adaptive remeshing functions (e.g.
with MMG) - with a uniform metric if you want a uniform mesh.
plex/tests/ex19 should show how it works.
Thanks
--
Nicolas
Steven
