Segfault when defining sizing field in NodeData using gmsh

[konstantinweise]

Dear MMG developers,

I encountered an issue when defining the sizing field in a NodeData array. My MMG call is as follows:

mmg3d_O3 -v 6 -nosurf -hgrad -1 -rmc -in ernie_with_sizing_field.msh -out ernie_with_sizing_field_mmg.msh

I get a segfault and after compiling mmg in debug mode, I was able to identify that it crashes here:

mmg/src/common/inout.c

Line 1352 in adf56d6

psl->m[idx] = dbuf[0];

I also tried to use the original gmsh mesh without the NodeData field using the corresponding -sol file but it does not getting recognized and loaded at all. The command I used was:

mmg3d_O3 -v 6 -nosurf -hgrad -1 -rmc -in ernie_with_sizing_field.msh -out ernie_with_sizing_field_mmg.msh -sol ernie.sol

Finally, after convertig the file into the medit format using meshio, I was able to remesh the problem with the sizing field. The only working version was:

mmg3d_O3 -v 6 -nosurf -hgrad -1 -rmc -in ernie.mesh -out ernie_with_sizing_field_mmg.msh

I would like to avoid the conversion step and directly write the sizing field into the NodeData field.

I provided a download link for the files for testing: testing_meshes

Thanks a lot!

Best regards!

Konstantin

[TorgeW]

I found the problem, mmg wants a exactly 3 integer-tags while usually a 4th one is used as well.
Would be nice if mmg would actually respect the number of integer tags and skip extra tags instead of breaking.

number-of-integer-tags # must be 3 for Mmg
Latex formula # ignored value
metric-type # type of metric ( 1:scalar, 3:vector, 9:tensor)
nbvals # number of metrics: must match with the number of nodes in the $Nodes field