Description
I'm filling an issue as I observe an Infinite loop in orient_polygon_soup() in the function void duplicate_singular_vertices() that is extracting links of vertices to detect if a vertex is non-manifold (singular). I cannot reproduce the error in an isolated program, only in a complex one.
The problem happens here:
if (next==v_id){
/// turn the otherway round
next = neighbors[0];
do{
P_ID other_p_id;
std::tie(next, other_p_id) = next_ccw_vertex_around_target(next, v_id, polygons, edges, marked_edges);
if (next==v_id) break;
visited_polygons.insert(other_p_id);
if(nb_link_ccs != 1)
vertices_to_duplicate.back().second.push_back(other_p_id);
}
while(true);
}
the pb happens because of a face having a degenerate edge, with the duplicated vertex being a T junction:
B----------------A
| |
| |
C-------DD-------E
| | |
| | |
| | |
F------- G-------H
f0: A-B-C-D-D-E
f1: E-D-G-H
f2: D-C-F-G
I'm not even sure we want to support such cases.