[MOAB-dev] MOAB finding shells bounding closed regions in nonmanifold mesh

[Steve Hughey]

Hello,

I am using MOAB as the basis for a sort of mesh-based geometry model in a
finite element/boundary element code. I must assume that the mesh
connectivity and Exodus block specifications are the only information I
have about the geometry. I have been able to use MOAB’s various adjacency
queries to break the input mesh into connected components with adjacencies
between them, largely along the lines of CUBIT’s mesh-based geometry
engine. The meshes are pretty general, containing quads, tris, hexes, tets,
prisms, and pyramids, and typically contain nonmanifold edges.

However, I am now faced with the problem of finding closed regions. I have
some ideas on how to do this based on concepts from half-facet data
structures, but the MOAB classes FBEngine and GeomTopoTool caught my
attention. I have tried reading the interface specification for these and
have been unable to determine whether they could be useful for my closed
regions problem. I have seen many allusions in the code to geometry and
topology representation, but I haven’t been able to connect the dots. My
hope is that someone has already thought through this problem and
implemented a solution. I would appreciate any insight you can provide, and
in the meantime I will continue testing things.

Thanks,
Steve