From 317846595385581195a2f2a99dd12abec812dc4c Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Sun, 26 Dec 2021 10:44:01 -0700 Subject: [PATCH] Also copy edge information in GridGenerator::flatten_triangulation(). --- source/grid/grid_generator.cc | 38 +++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/source/grid/grid_generator.cc b/source/grid/grid_generator.cc index 4ba2576a2a..4dc5da3366 100644 --- a/source/grid/grid_generator.cc +++ b/source/grid/grid_generator.cc @@ -7539,6 +7539,8 @@ namespace GridGenerator case 2: { + // Loop over the boundary faces of the triangulation and create + // objects that describe their boundary and manifold ids. for (const auto &face : in_tria.active_face_iterators() | IteratorFilters::AtBoundary()) { @@ -7559,6 +7561,13 @@ namespace GridGenerator case 3: { + std::vector user_flags_line; + in_tria.save_user_flags_line(user_flags_line); + const_cast &>(in_tria) + .clear_user_flags_line(); + + // Loop over the boundary faces of the triangulation and create + // objects that describe their boundary and manifold ids. for (const auto &face : in_tria.active_face_iterators() | IteratorFilters::AtBoundary()) { @@ -7572,8 +7581,37 @@ namespace GridGenerator subcelldata.boundary_quads.emplace_back( std::move(boundary_face)); + + // Then also loop over the edges and do the same. We would + // accidentally create duplicates for edges that are part of two + // boundary faces. To avoid this, use the user_flag on edges to + // mark those that we have already visited. (Note how we save + // and restore those above and below.) + for (unsigned int e = 0; e < face->n_lines(); ++e) + if (face->line(e)->user_flag_set() == false) + { + const typename Triangulation::line_iterator + edge = face->line(e); + CellData<1> boundary_edge; + + boundary_edge.vertices.resize(edge->n_vertices()); + for (const auto i : edge->vertex_indices()) + boundary_edge.vertices[i] = edge->vertex_index(i); + boundary_edge.boundary_id = edge->boundary_id(); + boundary_edge.manifold_id = edge->manifold_id(); + + subcelldata.boundary_lines.emplace_back( + std::move(boundary_edge)); + + edge->set_user_flag(); + } } + // Reset the user flags to their previous values: + const_cast &>(in_tria) + .load_user_flags_line(user_flags_line); + break; } default: -- 2.39.5