songsenand
/
cgal
mirror of https://github.com/CGAL/cgal
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

fix cheese18 --merge-facets 

The explanation of the bug:
`split_graph_into_polylines` can reverse the orientation of a polygon
This commit is contained in:
Laurent Rineau 2023-09-25 17:58:03 +02:00
parent 616cdfbc7a
commit 5bc5ec4f46
2 changed files with 24 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
Triangulation_3/include/CGAL/Constrained_Delaunay_triangulation_3.h
View File

@ -534,7 +534,7 @@ public:
const auto vb = *circ;
const auto c_id = this->constraint_from_extremities(va, vb);
if(c_id != Constraint_id{}) {
const bool constraint_c_id_is_reversed = true;
const bool constraint_c_id_is_reversed = va != (*this->constraint_hierarchy.vertices_in_constraint_begin(c_id));
border.push_back(Face_edge{c_id, constraint_c_id_is_reversed});
constraint_to_faces.emplace(c_id, polygon_contraint_id);
} else {
@ -635,9 +635,7 @@ private:
const auto v_end = this->constraint_hierarchy.vertices_in_constraint_end(c_id);
CGAL_assertion(std::distance(v_begin, v_end) >= 2);
auto va = *v_begin;
auto vb_it = v_end;
--vb_it;
auto vb = *vb_it;
auto vb = *std::prev(v_end);
if(reversed) {
using std::swap;
swap(va, vb);

24
Triangulation_3/test/Triangulation_3/cdt_3_from_off.cpp
View File

@ -132,7 +132,7 @@ int main(int argc, char* argv[])
try {
go(mesh, output_filename);
} catch(CGAL::Failure_exception& e) {
if(e.expression().find(std::string("orientation(p0, p1, p2, p3) == POSITIVE")) != std::string::npos)
if(e.expression().find(std::string("handles.back() == va")) != std::string::npos)
{
std::cerr << "BAD MESH! " << mesh.number_of_faces() << " faces\n";
std::ofstream bad("bad.off");
@ -302,8 +302,28 @@ int go(Mesh mesh, std::string output_filename) {
CDT_3_try {
if(merge_facets) {
for(int i = 0; i < nb_patches; ++i) {
const auto& edges = patch_edges[i];
auto& edges = patch_edges[i];
auto polylines = segment_soup_to_polylines(edges);
while(true) {
const auto non_closed_polylines_begin =
std::partition(polylines.begin(), polylines.end(),
[](const auto& polyline) { return polyline.front() == polyline.back(); });
if(non_closed_polylines_begin == polylines.end())
break;
edges.clear();
for(auto it = non_closed_polylines_begin; it != polylines.end(); ++it) {
auto& polyline = *it;
for(auto it = polyline.begin(), end = polyline.end() - 1; it != end; ++it) {
edges.emplace_back(*it, *(it + 1));
}
}
polylines.erase(non_closed_polylines_begin, polylines.end());
auto other_polylines = segment_soup_to_polylines(edges);
polylines.insert(polylines.end(),
std::make_move_iterator(other_polylines.begin()),
std::make_move_iterator(other_polylines.end()));
}
std::optional<int> face_index;
for(auto& polyline: polylines) {
assert(polyline.front() == polyline.back());