From 82f429ee308cbf7f3dc9f82e16b90ed02ef70115 Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Fri, 17 Nov 2017 14:42:09 +0000
Subject: [PATCH] Replace std::map by boost::unordered_map to speed up. We can
 even do better with Dynamic_property_map

---
 .../include/CGAL/vsa_approximation.h          | 14 +++---
 .../include/CGAL/vsa_metrics.h                | 50 +++++++++----------
 2 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/Surface_mesh_approximation/include/CGAL/vsa_approximation.h b/Surface_mesh_approximation/include/CGAL/vsa_approximation.h
index 3ee8e1991ef..337781508e9 100644
--- a/Surface_mesh_approximation/include/CGAL/vsa_approximation.h
+++ b/Surface_mesh_approximation/include/CGAL/vsa_approximation.h
@@ -21,10 +21,10 @@
 #include <boost/foreach.hpp>
 #include <boost/optional.hpp>
 
+#include <boost/unordered_map.hpp>
 #include <vector>
 #include <cmath>
-#include <cstdlib>
-#include <map>
+
 #include <queue>
 #include <iterator>
 
@@ -100,7 +100,7 @@ private:
   typedef typename boost::graph_traits<TriangleMesh>::face_descriptor face_descriptor;
 
   // internal typedefs
-  typedef boost::associative_property_map<std::map<vertex_descriptor, int> > Vertex_anchor_map;
+  typedef boost::associative_property_map<boost::unordered_map<vertex_descriptor, int> > Vertex_anchor_map;
 
   typedef std::vector<halfedge_descriptor> Chord_vector;
   typedef typename Chord_vector::iterator Chord_vector_iterator;
@@ -228,10 +228,10 @@ private:
   Compute_scalar_product_3 scalar_product_functor;
 
   // The facet proxy index map.
-  std::map<face_descriptor, std::size_t> internal_fidx_map;
-  boost::associative_property_map<std::map<face_descriptor, std::size_t> > fproxy_map;
+  boost::unordered_map<face_descriptor, std::size_t> internal_fidx_map;
+  boost::associative_property_map<boost::unordered_map<face_descriptor, std::size_t> > fproxy_map;
   // The attached anchor index of a vertex.
-  std::map<vertex_descriptor, int> internal_vidx_map;
+  boost::unordered_map<vertex_descriptor, int> internal_vidx_map;
   Vertex_anchor_map vanchor_map;
 
   // Proxies.
@@ -1495,7 +1495,7 @@ private:
     typedef typename SubGraph::vertex_descriptor sg_vertex_descriptor;
     typedef std::vector<sg_vertex_descriptor> VertexVector;
 
-    typedef std::map<vertex_descriptor, sg_vertex_descriptor> VertexMap;
+    typedef boost::unordered_map<vertex_descriptor, sg_vertex_descriptor> VertexMap;
     typedef boost::associative_property_map<VertexMap> ToSGVertexMap;
     VertexMap vmap;
     ToSGVertexMap to_sgv_map(vmap);
diff --git a/Surface_mesh_approximation/include/CGAL/vsa_metrics.h b/Surface_mesh_approximation/include/CGAL/vsa_metrics.h
index 9ae590c8ae7..5eea2e7d494 100644
--- a/Surface_mesh_approximation/include/CGAL/vsa_metrics.h
+++ b/Surface_mesh_approximation/include/CGAL/vsa_metrics.h
@@ -9,7 +9,7 @@
 #include <CGAL/linear_least_squares_fitting_3.h>
 #include <boost/graph/graph_traits.hpp>
 
-#include <map>
+#include <boost/unordered_map.hpp>
 #include <list>
 
 namespace CGAL {
@@ -72,8 +72,8 @@ class L21_metric
   typedef typename boost::graph_traits<TriangleMesh>::face_descriptor face_descriptor;
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
-  typedef boost::associative_property_map<std::map<face_descriptor, Vector_3> > FacetNormalMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, FT> > FacetAreaMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, Vector_3> > FacetNormalMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, FT> > FacetAreaMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -107,8 +107,8 @@ public:
   }
 
 private:
-  std::map<face_descriptor, Vector_3> facet_normals;
-  std::map<face_descriptor, FT> facet_areas;
+  boost::unordered_map<face_descriptor, Vector_3> facet_normals;
+  boost::unordered_map<face_descriptor, FT> facet_areas;
   const FacetNormalMap normal_pmap;
   const FacetAreaMap area_pmap;
   Construct_scaled_vector_3 scale_functor;
@@ -138,8 +138,8 @@ class L21_metric<TriangleMesh,
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
   typedef typename boost::property_map<TriangleMesh, boost::vertex_point_t>::type VertexPointMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, Vector_3> > FacetNormalMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, FT> > FacetAreaMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, Vector_3> > FacetNormalMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, FT> > FacetAreaMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -174,8 +174,8 @@ public:
   }
 
 private:
-  std::map<face_descriptor, Vector_3> facet_normals;
-  std::map<face_descriptor, FT> facet_areas;
+  boost::unordered_map<face_descriptor, Vector_3> facet_normals;
+  boost::unordered_map<face_descriptor, FT> facet_areas;
   const FacetNormalMap normal_pmap;
   const FacetAreaMap area_pmap;
   Construct_scaled_vector_3 scale_functor;
@@ -204,7 +204,7 @@ class L21_metric<TriangleMesh,
   typedef typename boost::graph_traits<TriangleMesh>::face_descriptor face_descriptor;
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
-  typedef boost::associative_property_map<std::map<face_descriptor, Vector_3> > FacetNormalMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, Vector_3> > FacetNormalMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -237,7 +237,7 @@ public:
   }
 
 private:
-  std::map<face_descriptor, Vector_3> facet_normals;
+  boost::unordered_map<face_descriptor, Vector_3> facet_normals;
   const FacetNormalMap normal_pmap;
   Construct_scaled_vector_3 scale_functor;
   Compute_scalar_product_3 scalar_product_functor;
@@ -265,7 +265,7 @@ class L21_metric<TriangleMesh,
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
   typedef typename boost::property_map<TriangleMesh, boost::vertex_point_t>::type VertexPointMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, Vector_3> > FacetNormalMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, Vector_3> > FacetNormalMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -298,7 +298,7 @@ public:
   }
 
 private:
-  std::map<face_descriptor, Vector_3> facet_normals;
+  boost::unordered_map<face_descriptor, Vector_3> facet_normals;
   const FacetNormalMap normal_pmap;
   Construct_scaled_vector_3 scale_functor;
   Compute_scalar_product_3 scalar_product_functor;
@@ -335,8 +335,8 @@ class L21_proxy_fitting
   typedef typename boost::graph_traits<TriangleMesh>::face_descriptor face_descriptor;
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
-  typedef boost::associative_property_map<std::map<face_descriptor, Vector_3> > FacetNormalMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, FT> > FacetAreaMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, Vector_3> > FacetNormalMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, FT> > FacetAreaMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -384,8 +384,8 @@ public:
   }
 
 private:
-  std::map<face_descriptor, Vector_3> facet_normals;
-  std::map<face_descriptor, FT> facet_areas;
+  boost::unordered_map<face_descriptor, Vector_3> facet_normals;
+  boost::unordered_map<face_descriptor, FT> facet_areas;
   const FacetNormalMap normal_pmap;
   const FacetAreaMap area_pmap;
   Construct_scaled_vector_3 scale_functor;
@@ -411,8 +411,8 @@ class L21_proxy_fitting<TriangleMesh,
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
   typedef typename boost::property_map<TriangleMesh, boost::vertex_point_t>::type VertexPointMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, Vector_3> > FacetNormalMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, FT> > FacetAreaMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, Vector_3> > FacetNormalMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, FT> > FacetAreaMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -461,8 +461,8 @@ public:
   }
 
 private:
-  std::map<face_descriptor, Vector_3> facet_normals;
-  std::map<face_descriptor, FT> facet_areas;
+  boost::unordered_map<face_descriptor, Vector_3> facet_normals;
+  boost::unordered_map<face_descriptor, FT> facet_areas;
   const FacetNormalMap normal_pmap;
   const FacetAreaMap area_pmap;
   Construct_scaled_vector_3 scale_functor;
@@ -496,7 +496,7 @@ class L2_metric
   typedef typename boost::graph_traits<TriangleMesh>::face_descriptor face_descriptor;
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
-  typedef boost::associative_property_map<std::map<face_descriptor, FT> > FacetAreaMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, FT> > FacetAreaMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -533,7 +533,7 @@ public:
 
 private:
   const TriangleMesh *mesh;
-  std::map<face_descriptor, FT> facet_areas;
+  boost::unordered_map<face_descriptor, FT> facet_areas;
   const FacetAreaMap area_pmap;
   const VertexPointMap point_pmap;
 };
@@ -554,7 +554,7 @@ class L2_metric<TriangleMesh,
   typedef typename boost::graph_traits<TriangleMesh>::halfedge_descriptor halfedge_descriptor;
 
   typedef typename boost::property_map<TriangleMesh, boost::vertex_point_t>::type VertexPointMap;
-  typedef boost::associative_property_map<std::map<face_descriptor, FT> > FacetAreaMap;
+  typedef boost::associative_property_map<boost::unordered_map<face_descriptor, FT> > FacetAreaMap;
 
 public:
   // type required by `ErrorMetric` concept
@@ -592,7 +592,7 @@ public:
 
 private:
   const TriangleMesh *mesh;
-  std::map<face_descriptor, FT> facet_areas;
+  boost::unordered_map<face_descriptor, FT> facet_areas;
   const FacetAreaMap area_pmap;
   const VertexPointMap point_pmap;
 };