From c19c648682d023d680cb7231528c65c6f5e6bc70 Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Thu, 10 Oct 2024 19:35:39 +0100
Subject: [PATCH] Add index_pmap

---
 .../graph/graph_traits_geometrycentral.h      | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/BGL/include/CGAL/boost/graph/graph_traits_geometrycentral.h b/BGL/include/CGAL/boost/graph/graph_traits_geometrycentral.h
index d30982c7c6aa..8ed7d7c87993 100644
--- a/BGL/include/CGAL/boost/graph/graph_traits_geometrycentral.h
+++ b/BGL/include/CGAL/boost/graph/graph_traits_geometrycentral.h
@@ -738,6 +738,25 @@ class GC_point_pmap
   const VertexPositionGeometry* vpg_;
 };
 
+template <typename K, typename VEF>
+class GC_index_pmap
+{
+public:
+  typedef boost::readable_property_map_tag category;
+  typedef std::size_t                      value_type;
+  typedef std::size_t                      reference;
+  typedef VEF                              key_type;
+
+  GC_index_pmap()
+  {}
+
+  value_type operator[](const key_type& vd) const
+  {
+    return vd.getIndex();
+  }
+
+  friend inline value_type get(const GC_index_pmap& m, const key_type& k) { return m[k]; }
+};
 
 } // namespace surface
 } // namespace geometrycentral