From 87d114137f992a055cd0f51d720c0bec7deed633 Mon Sep 17 00:00:00 2001
From: Giles Bathgate <giles.bathgate@gmail.com>
Date: Sun, 7 Feb 2021 09:52:45 +0000
Subject: [PATCH 1/2] Calculate indices only when required in
 check_integrity_and_topological_planarity

---
 .../include/CGAL/Nef_S2/SM_const_decorator.h  | 41 +++++++++++++------
 1 file changed, 28 insertions(+), 13 deletions(-)

diff --git a/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h b/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h
index 74b16be98ae..dac5514735f 100644
--- a/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h
+++ b/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h
@@ -273,36 +273,51 @@ The macros are then |CGAL_forall_svertices(v,M)|,
 |CGAL_forall_sfaces(f,M)|, |CGAL_forall_sface_cycles_of(fc,F)|
 where |M| is a sphere map and |F| is a sface.}*/
 
+private:
+std::string get_svertex_index(SVertex_const_handle) const;
+std::string get_shalfedge_index(SHalfedge_const_handle e) const;
+
 }; // SM_const_decorator
 
 
 
+template <typename SM_>
+std::string SM_const_decorator<SM_>::
+get_svertex_index(SVertex_const_handle v) const
+{
+  Object_index<SVertex_const_handle>
+    VI(svertices_begin(),svertices_end(),'v');
+  return VI(v);
+}
+
+template <typename SM_>
+std::string SM_const_decorator<SM_>::
+get_shalfedge_index(SHalfedge_const_handle e) const
+{
+  Object_index<SHalfedge_const_handle>
+    EI(shalfedges_begin(),shalfedges_end(),'e');
+  return EI(e);
+}
+
 template <typename SM_>
 void SM_const_decorator<SM_>::
 check_integrity_and_topological_planarity(bool faces) const
 {
   CGAL_NEF_TRACEN("check_integrity_and_topological_planarity:");
-  using CGAL::Object_index;
-  Object_index<SVertex_const_iterator>
-    VI(svertices_begin(),svertices_end(),'v');
-  Object_index<SHalfedge_const_iterator>
-    EI(shalfedges_begin(),shalfedges_end(),'e');
-  Object_index<SFace_const_iterator>
-    FI(sfaces_begin(),sfaces_end(),'f');
+
   SVertex_const_handle v;
   int iso_vert_num=0;
   /* check the source links of out edges and count isolated vertices */
   CGAL_forall_svertices(v,*this) {
     if ( is_isolated(v) ) {
       if ( faces )
-        CGAL_assertion_msg(v->incident_sface() != SFace_const_handle(), VI(v).c_str());
+        CGAL_assertion_msg(v->incident_sface() != SFace_const_handle(), get_svertex_index(v).c_str());
       ++iso_vert_num;
     } else {
-      CGAL_assertion_msg(first_out_edge(v) != SHalfedge_const_handle(),
-      VI(v).c_str());
-      CGAL_NEF_TRACEN(v->point()<<" "<<EI(first_out_edge(v)));
-      CGAL_assertion_msg(first_out_edge(v)->source() == v,
-                         VI(v).c_str());
+      CGAL_assertion_code(SHalfedge_const_handle e=first_out_edge(v));
+      CGAL_assertion_msg(e != SHalfedge_const_handle(), get_svertex_index(v).c_str());
+      CGAL_NEF_TRACEN(v->point()<<" "<<get_shalfedge_index(e));
+      CGAL_assertion_msg(e->source() == v, get_svertex_index(v).c_str());
     }
   }
 

From 9c6712c3b127478de882577229aec8d1bb2105c2 Mon Sep 17 00:00:00 2001
From: Giles Bathgate <giles.bathgate@gmail.com>
Date: Mon, 8 Feb 2021 19:32:33 +0000
Subject: [PATCH 2/2] Calculate indices correctly when trace enabled

---
 Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h b/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h
index dac5514735f..fe38af9ab44 100644
--- a/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h
+++ b/Nef_S2/include/CGAL/Nef_S2/SM_const_decorator.h
@@ -275,7 +275,6 @@ where |M| is a sphere map and |F| is a sface.}*/
 
 private:
 std::string get_svertex_index(SVertex_const_handle) const;
-std::string get_shalfedge_index(SHalfedge_const_handle e) const;
 
 }; // SM_const_decorator
 
@@ -290,21 +289,15 @@ get_svertex_index(SVertex_const_handle v) const
   return VI(v);
 }
 
-template <typename SM_>
-std::string SM_const_decorator<SM_>::
-get_shalfedge_index(SHalfedge_const_handle e) const
-{
-  Object_index<SHalfedge_const_handle>
-    EI(shalfedges_begin(),shalfedges_end(),'e');
-  return EI(e);
-}
-
 template <typename SM_>
 void SM_const_decorator<SM_>::
 check_integrity_and_topological_planarity(bool faces) const
 {
   CGAL_NEF_TRACEN("check_integrity_and_topological_planarity:");
-
+#ifdef CGAL_USE_TRACE
+  Object_index<SHalfedge_const_iterator>
+    EI(shalfedges_begin(),shalfedges_end(),'e');
+#endif
   SVertex_const_handle v;
   int iso_vert_num=0;
   /* check the source links of out edges and count isolated vertices */
@@ -316,7 +309,7 @@ check_integrity_and_topological_planarity(bool faces) const
     } else {
       CGAL_assertion_code(SHalfedge_const_handle e=first_out_edge(v));
       CGAL_assertion_msg(e != SHalfedge_const_handle(), get_svertex_index(v).c_str());
-      CGAL_NEF_TRACEN(v->point()<<" "<<get_shalfedge_index(e));
+      CGAL_NEF_TRACEN(v->point()<<" "<<EI[first_out_edge(v)]);
       CGAL_assertion_msg(e->source() == v, get_svertex_index(v).c_str());
     }
   }