From 725257f8e7f94bc46aa3d24d0659870ca9722050 Mon Sep 17 00:00:00 2001
From: Daniel Arndt <daniel.arndt@iwr.uni-heidelberg.de>
Date: Wed, 1 Aug 2018 20:26:25 +0200
Subject: [PATCH] Allow detecting mutiple duplicates in
 GridTools::delete_duplicated_vertices

---
 include/deal.II/grid/grid_tools.h |  3 ++-
 source/grid/grid_generator.cc     | 18 ++++++------------
 source/grid/grid_tools.cc         |  3 ---
 3 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/include/deal.II/grid/grid_tools.h b/include/deal.II/grid/grid_tools.h
index e87b016dcf..f21a8ba5ff 100644
--- a/include/deal.II/grid/grid_tools.h
+++ b/include/deal.II/grid/grid_tools.h
@@ -301,7 +301,8 @@ namespace GridTools
    * the vertices with indices in @p considered_vertices are tested for
    * equality. This speeds up the algorithm, which is quadratic and thus quite
    * slow to begin with. However, if you wish to consider all vertices, simply
-   * pass an empty vector.
+   * pass an empty vector. In that case, the function fills
+   * @p considered_vertices with all vertices.
    *
    * Two vertices are considered equal if their difference in each coordinate
    * direction is less than @p tol.
diff --git a/source/grid/grid_generator.cc b/source/grid/grid_generator.cc
index 50d0cb86fc..89aec1b357 100644
--- a/source/grid/grid_generator.cc
+++ b/source/grid/grid_generator.cc
@@ -4304,18 +4304,12 @@ namespace GridGenerator
       }
 
     // throw out duplicated vertices
-    // since GridTools::delete_duplicated_vertices can only consider
-    // one duplications at once, we have to call the function one time less
-    // than the number of Triangulation objects to be merged.
-    for (unsigned int i = 0; i < triangulations.size(); ++i)
-      {
-        std::vector<unsigned int> considered_vertices;
-        GridTools::delete_duplicated_vertices(vertices,
-                                              cells,
-                                              subcell_data,
-                                              considered_vertices,
-                                              duplicated_vertex_tolerance);
-      }
+    std::vector<unsigned int> considered_vertices;
+    GridTools::delete_duplicated_vertices(vertices,
+                                          cells,
+                                          subcell_data,
+                                          considered_vertices,
+                                          duplicated_vertex_tolerance);
 
     // reorder the cells to ensure that they satisfy the convention for
     // edge and face directions
diff --git a/source/grid/grid_tools.cc b/source/grid/grid_tools.cc
index 248998f535..1b886afc14 100644
--- a/source/grid/grid_tools.cc
+++ b/source/grid/grid_tools.cc
@@ -579,9 +579,6 @@ namespace GridTools
               {
                 new_vertex_numbers[considered_vertices[j]] =
                   considered_vertices[i];
-                // we do not suppose, that there might be another duplicate
-                // vertex, so break here
-                break;
               }
           }
       }
-- 
2.39.5