I have a 3d mesh in .mesh format which can be read by medit visualization program. However I need to convert it into the .nodes, .ele and .face format that is the output format of tetgen (the 3d Delaunay tetrahedralization program) . What is the best way to do this conversion of formats? Is there a free program available to do this conversion?
The MEDIT_TO_FEM program produces .node and .ele files from an medit .mesh file.
You might have to hack it to get triangles, though. It's simple: each (positively-oriented) tetrahedral element with vertices
v0 v1 v2 v3
has triangular faces
v0 v1 v2
v1 v3 v2
v2 v3 v0
v3 v1 v2
The orientation of the faces will of course depend on the orientation of the element, so your triangles might require a different ordering of their vertices.