The geometric decomposition constraint (issue #921 (closed)) may be used to restrict the mesh decomposition on a geometrical basis. For example, to avoid splitting of a sensitive feature across processor boundaries. The geometry constraints are described by topoSet face sources, which can include basic geometrically entities (sphere, box, cylinder), mesh entities (eg, faces associated with a cellSet) or an arbitrary closed surface (stl, obj, etc). The support for arbitrary closed surfaces uses a triSurfaceMesh topoSetFaceSource.