Use same tolerance in "Tet* walk (Tet *t, Vert *v, int maxx, double &totSearch, int thread)" as in "static Tet* tetContainsV (Vert *v, cavityContainer &cavity)" as now the initial tet from the walk function may be some flat tets away. When building up the cavity, flat tets between the initial tet and the tet containing the vertex may not include the vertex in their sphere, resulting in that they won't end up in the cavity and so the function "tetContainsV" will not find any tet. What will result in invalid cavities, unable to recover the boundary and finally, no mesh.