CGAL users discussion list

[Bart Janssens <>]

On Sat, Jan 31, 2009 at 12:58 AM, Peter Hachenberger
<>
 wrote:
> you can patch Nef_3 in the following way to get
> rid of the inconsistencies:
> Halfedge:
> bool is_twin() const
> { return twin_->source()->point() < center_vertex_->point(); }

Hi Peter,

Thanks for the help! Attached is the patch after implementing your
suggestions. The only deviation is in Halfedge: it seems that twin_
can be null, so I added an extra check.

Cheers,

-- 
Bart
diff -urp CGAL-3.4/include/CGAL/Nef_3/binop_intersection_tests.h CGAL-3.4-patched/include/CGAL/Nef_3/binop_intersection_tests.h
--- CGAL-3.4/include/CGAL/Nef_3/binop_intersection_tests.h	2008-12-19 14:50:49.000000000 +0100
+++ CGAL-3.4-patched/include/CGAL/Nef_3/binop_intersection_tests.h	2009-01-31 14:59:50.000000000 +0100
@@ -24,6 +24,7 @@
 #include <vector>
 #include <iostream>
 #include <CGAL/Timer.h>
+#include <CGAL/Random.h>
 
 CGAL_BEGIN_NAMESPACE
 
@@ -136,6 +137,7 @@ struct binop_intersection_test_segment_t
                   SNC_structure& sncp,
                   SNC_structure& snc1i)
   {
+    CGAL::Random dummy(12345);
     Halfedge_iterator e0, e1;
     Halffacet_iterator f0, f1;
     std::vector<Nef_box> a, b;
diff -urp CGAL-3.4/include/CGAL/Nef_3/Halfedge.h CGAL-3.4-patched/include/CGAL/Nef_3/Halfedge.h
--- CGAL-3.4/include/CGAL/Nef_3/Halfedge.h	2008-12-19 14:50:49.000000000 +0100
+++ CGAL-3.4-patched/include/CGAL/Nef_3/Halfedge.h	2009-02-01 22:10:20.000000000 +0100
@@ -133,7 +133,7 @@ class Halfedge_base
 	  return os.str();
 	}
 
-      bool is_twin() const { return (&*twin_ < this); }
+      bool is_twin() const { return twin_ == NULL || twin_->source()->point() < center_vertex_->point(); }
 
       bool is_valid( bool verb = false, int level = 0) const {
       
diff -urp CGAL-3.4/include/CGAL/Nef_3/Halffacet.h CGAL-3.4-patched/include/CGAL/Nef_3/Halffacet.h
--- CGAL-3.4/include/CGAL/Nef_3/Halffacet.h	2008-12-19 14:50:49.000000000 +0100
+++ CGAL-3.4-patched/include/CGAL/Nef_3/Halffacet.h	2009-01-31 14:57:13.000000000 +0100
@@ -110,7 +110,7 @@ class Halffacet_base  {
       Halffacet_cycle_const_iterator facet_cycles_end() const
       { return boundary_entry_objects_.end(); }
 
-      bool is_twin() const { return (&*twin_ < this); }
+      bool is_twin() const { return (CGAL::ORIGIN + twin_->plane().orthogonal_vector()) < (CGAL::ORIGIN +  supporting_plane_.orthogonal_vector()); }
 
       bool is_valid( bool verb = false, int level = 0) const {
       
diff -urp CGAL-3.4/include/CGAL/Nef_3/SHalfedge.h CGAL-3.4-patched/include/CGAL/Nef_3/SHalfedge.h
--- CGAL-3.4/include/CGAL/Nef_3/SHalfedge.h	2008-12-19 14:50:49.000000000 +0100
+++ CGAL-3.4-patched/include/CGAL/Nef_3/SHalfedge.h	2009-01-31 14:57:46.000000000 +0100
@@ -202,7 +202,7 @@ class SHalfedge_base  { 
 	return os.str();
       }
 
-    bool is_twin() const { return (&*twin_ < this); }
+    bool is_twin() const { return (CGAL::ORIGIN + twin_->circle().orthogonal_vector()) < (CGAL::ORIGIN +  circle_.orthogonal_vector()); }
 
     bool is_valid( bool verb = false, int level = 0) const {
       
diff -urp CGAL-3.4/include/CGAL/Nef_3/SHalfloop.h CGAL-3.4-patched/include/CGAL/Nef_3/SHalfloop.h
--- CGAL-3.4/include/CGAL/Nef_3/SHalfloop.h	2008-12-19 14:50:49.000000000 +0100
+++ CGAL-3.4-patched/include/CGAL/Nef_3/SHalfloop.h	2009-01-31 14:58:04.000000000 +0100
@@ -102,7 +102,7 @@ class SHalfloop_base {
 	return os.str();
       }
 
-    bool is_twin() const { return (&*twin_ < this); }
+    bool is_twin() const { return (CGAL::ORIGIN + twin_->circle().orthogonal_vector()) < (CGAL::ORIGIN +  circle_.orthogonal_vector()); }
 
     bool is_valid( bool verb = false, int level = 0) const {