From e55fd5cdcd5014213d657e3164c668d89346469b Mon Sep 17 00:00:00 2001
From: Monique Teillaud <Monique.Teillaud@sophia.inria.fr>
Date: Sun, 11 Jun 2006 13:19:01 +0000
Subject: [PATCH] fix the manual, and mention the problems pointed out by
 Laurent R. about non robustness with regular_traits<predefined_kernels>

---
 Triangulation_3/doc_tex/Triangulation_3/Triang3.tex  | 12 ++++++++++--
 .../examples/Triangulation_3/example_regular.C       |  8 ++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/Triangulation_3/doc_tex/Triangulation_3/Triang3.tex b/Triangulation_3/doc_tex/Triangulation_3/Triang3.tex
index def0f9367c8..e0c88476cac 100644
--- a/Triangulation_3/doc_tex/Triangulation_3/Triang3.tex
+++ b/Triangulation_3/doc_tex/Triangulation_3/Triang3.tex
@@ -332,9 +332,17 @@ It can be used as a traits class for
 \ccc{Regular_triangulation_3<RegularTriangulationTraits_3,
 TriangulationDataStructure_3>}.
 
-There is also another model of the traits concept,
+\textbf{Note that for regular triangulations, plugging a filtered kernel such
+as \ccc{Exact_predicates_inexact_constructions_kernel} or
+\ccc{Exact_predicates_exact_constructions_kernel} in
+\ccc{Regular_triangulation_euclidean_traits_3<K,Weight>} will in fact
+not provide exact predicates since the weighted points and the
+predicates on them are not defined in the \cgal\ kernels.} 
+To solve this, there is also another model of the traits concept,
 \ccc{Regular_triangulation_filtered_traits_3<FK>}, which is providing filtered
-predicates (exact and efficient).
+predicates (exact and efficient). The argument \ccc{FK} must be a
+model of the \ccc{Kernel} concept, and it is also restricted to be a
+instance of the \ccc{Filtered_kernel} template. 
 
 \subsection{The Triangulation Data Structure Parameter}
 \label{Triangulation3-sec-tds}
diff --git a/Triangulation_3/examples/Triangulation_3/example_regular.C b/Triangulation_3/examples/Triangulation_3/example_regular.C
index eaf24156e0e..3e8058a14b1 100644
--- a/Triangulation_3/examples/Triangulation_3/example_regular.C
+++ b/Triangulation_3/examples/Triangulation_3/example_regular.C
@@ -3,13 +3,17 @@
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 #include <CGAL/Regular_triangulation_3.h>
 #include <CGAL/Regular_triangulation_euclidean_traits_3.h>
-
+#include <CGAL/Regular_triangulation_filtered_traits_3.h>
 #include <cassert>
 #include <vector>
 
+//note that the usual
+//struct K : public CGAL::Exact_predicates_inexact_constructions_kernel {};
+//does not work here (because there is a partial specialization in
+//Regular_triangulation_filtered_traits_3
 typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
 
-typedef CGAL::Regular_triangulation_euclidean_traits_3<K>   Traits;
+typedef CGAL::Regular_triangulation_filtered_traits_3<K>    Traits;
 
 typedef Traits::RT                                          Weight;
 typedef Traits::Bare_point                                  Point;