From 48b17ff7d0376cf344910459428ba9bc179d48cb Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@math.tamu.edu>
Date: Thu, 3 Apr 2014 00:51:26 +0000
Subject: [PATCH] Unify several copies of the same function into a single
 templated one. Saves a good amount of duplicated code.

git-svn-id: https://svn.dealii.org/trunk@32708 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/source/distributed/tria.cc | 109 ++++++++---------------------
 1 file changed, 29 insertions(+), 80 deletions(-)

diff --git a/deal.II/source/distributed/tria.cc b/deal.II/source/distributed/tria.cc
index 4085903ce0..770dc964bb 100644
--- a/deal.II/source/distributed/tria.cc
+++ b/deal.II/source/distributed/tria.cc
@@ -3530,104 +3530,52 @@ namespace parallel
       }
     }
 
-    template <>
-    void
-    Triangulation<1,1>::
-    fill_vertices_with_ghost_neighbors
-    (std::map<unsigned int, std::set<dealii::types::subdomain_id> >
-     &vertices_with_ghost_neighbors)
-    {
-      Assert (false, ExcNotImplemented());
-    }
-
-    template <>
-    void
-    Triangulation<1,2>::
-    fill_vertices_with_ghost_neighbors
-    (std::map<unsigned int, std::set<dealii::types::subdomain_id> >
-     &vertices_with_ghost_neighbors)
-    {
-      Assert (false, ExcNotImplemented());
-    }
-
-    template <>
-    void
-    Triangulation<1,3>::
-    fill_vertices_with_ghost_neighbors
-    (std::map<unsigned int, std::set<dealii::types::subdomain_id> >
-     &vertices_with_ghost_neighbors)
-    {
-      Assert (false, ExcNotImplemented());
-    }
 
     /**
      * Determine the neighboring subdomains that are adjacent to each vertex.
-     * This is achieved via the p4est_iterate tool
+     * This is achieved via the p4est_iterate/p8est_iterate tool
      */
-    template <>
+    template <int dim, int spacedim>
     void
-    Triangulation<2,2>::
+    Triangulation<dim,spacedim>::
     fill_vertices_with_ghost_neighbors
     (std::map<unsigned int, std::set<dealii::types::subdomain_id> >
      &vertices_with_ghost_neighbors)
     {
-      struct find_ghosts<2,2> fg;
+      Assert (dim>1, ExcNotImplemented());
 
-      fg.subids = sc_array_new (sizeof (dealii::types::subdomain_id));
-      fg.triangulation = this;
-      fg.vertices_with_ghost_neighbors = &(vertices_with_ghost_neighbors);
-
-      p4est_iterate (this->parallel_forest, this->parallel_ghost, static_cast<void *>(&fg),
-                     NULL, find_ghosts_face<2,2>, find_ghosts_corner<2,2>);
-
-      sc_array_destroy (fg.subids);
-    }
-
-    /**
-     * Determine the neighboring subdomains that are adjacent to each vertex.
-     * This is achieved via the p4est_iterate tool
-     */
-    template <>
-    void
-    Triangulation<2,3>::
-    fill_vertices_with_ghost_neighbors
-    (std::map<unsigned int, std::set<dealii::types::subdomain_id> >
-     &vertices_with_ghost_neighbors)
-    {
-      struct find_ghosts<2,3> fg;
+      struct find_ghosts<dim,spacedim> fg;
 
       fg.subids = sc_array_new (sizeof (dealii::types::subdomain_id));
       fg.triangulation = this;
-      fg.vertices_with_ghost_neighbors = &(vertices_with_ghost_neighbors);
+      fg.vertices_with_ghost_neighbors = &vertices_with_ghost_neighbors;
 
-      p4est_iterate (this->parallel_forest, this->parallel_ghost, static_cast<void *>(&fg),
-                     NULL, find_ghosts_face<2,3>, find_ghosts_corner<2,3>);
+      // switch between functions. to make the compiler happy, we need to cast
+      // the first two arguments to the type p[48]est_iterate wants to see. this
+      // cast is the identity cast in each of the two branches, so it is safe.
+      switch (dim)
+      {
+      case 2:
+        p4est_iterate (reinterpret_cast<internal::p4est::types<2>::forest*>(this->parallel_forest),
+                       reinterpret_cast<internal::p4est::types<2>::ghost*>(this->parallel_ghost),
+                       static_cast<void *>(&fg),
+                       NULL, find_ghosts_face<2,spacedim>, find_ghosts_corner<2,spacedim>);
+        break;
+
+      case 3:
+        p8est_iterate (reinterpret_cast<internal::p4est::types<3>::forest*>(this->parallel_forest),
+                       reinterpret_cast<internal::p4est::types<3>::ghost*>(this->parallel_ghost),
+                       static_cast<void *>(&fg),
+                       NULL, find_ghosts_face<3,spacedim>, find_ghosts_edge<3,spacedim>, find_ghosts_corner<3,spacedim>);
+        break;
+
+      default:
+        Assert (false, ExcNotImplemented());
+      }
 
       sc_array_destroy (fg.subids);
     }
 
-    /**
-     * Determine the neighboring subdomains that are adjacent to each vertex.
-     * This is achieved via the p8est_iterate tool
-     */
-    template <>
-    void
-    Triangulation<3,3>::
-    fill_vertices_with_ghost_neighbors
-    (std::map<unsigned int, std::set<dealii::types::subdomain_id> >
-     &vertices_with_ghost_neighbors)
-    {
-      struct find_ghosts<3,3> fg;
-
-      fg.subids = sc_array_new (sizeof (dealii::types::subdomain_id));
-      fg.triangulation = this;
-      fg.vertices_with_ghost_neighbors = &(vertices_with_ghost_neighbors);
-
-      p8est_iterate (this->parallel_forest, this->parallel_ghost, static_cast<void *>(&fg),
-                     NULL, find_ghosts_face<3,3>, find_ghosts_edge<3,3>, find_ghosts_corner<3,3>);
-
-      sc_array_destroy (fg.subids);
-    }
 
     template <int dim, int spacedim>
     MPI_Comm
@@ -3636,6 +3584,7 @@ namespace parallel
       return mpi_communicator;
     }
 
+
     template<int dim, int spacedim>
     void
     Triangulation<dim,spacedim>::add_periodicity
-- 
2.39.5