Picking mesh elements that are not on the border of the mesh
vm = VoronoiMesh[pts, {-1, 1}]
HighlightMesh[vm, MeshCellIndex[vm, {2, "Interior"}]]
Related: Boundary cells of a mesh?
Show[vm, Epilog -> {Opacity[.7, Orange], MeshPrimitives[vm, {2, "Interior"}]}]
For planar MeshRegion
that arise from DelaunayMesh
or VoronoiMesh
, usually
R["InteriorFaces"]
should work.
A more general and more transparent ways is to use the package "IGraphM`"
by Szabolcs as follows:
Needs["IGraphM`"]
A = IGMeshCellAdjacencyMatrix[R, 1, 2];
bndedges = Random`Private`PositionsOf[Total[A, {2}], 1];
interiorfaces = Random`Private`PositionsOf[Total[A[[bndedges]]], 0];
HighlightMesh[R, Thread[{2, interiorfaces}]]