From: Peter Munch <peterrmuench@gmail.com>
Date: Mon, 22 Nov 2021 10:28:34 +0000 (+0100)
Subject: Fix GridGenerator::merge_triangulations() for simplex meshes
X-Git-Tag: v9.4.0-rc1~812^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7a17b27ce74859ae075a92ce4fed542e6445b5ba;p=dealii.git

Fix GridGenerator::merge_triangulations() for simplex meshes
---

diff --git a/source/grid/grid_generator.cc b/source/grid/grid_generator.cc
index 36f03a9226..7d961f01ba 100644
--- a/source/grid/grid_generator.cc
+++ b/source/grid/grid_generator.cc
@@ -6463,7 +6463,11 @@ namespace GridGenerator
 
     // reorder the cells to ensure that they satisfy the convention for
     // edge and face directions
-    GridTools::consistently_order_cells(cells);
+    if (std::all_of(cells.begin(), cells.end(), [](const auto &cell) {
+          return cell.vertices.size() ==
+                 ReferenceCells::get_hypercube<dim>().n_vertices();
+        }))
+      GridTools::consistently_order_cells(cells);
     result.clear();
     result.create_triangulation(vertices, cells, subcell_data);
   }