CGAL users discussion list

["Lehtonen, Matti/HIIT" <>]

Hi!

Version:
// $URL:
svn+ssh://scm.gforge.inria.fr/svn/cgal/branches/CGAL-3.5-branch/Surface_mesh_simplification/include/CGAL/Surface_mesh_simplification/halfedge_collapse_Polyhedron_3.h
$
// $Id: halfedge_collapse_Polyhedron_3.h 50078 2009-06-25 15:12:52Z fcacciola 
$

Description:
* When a triangle is part of border such a way that a vertex is part of border
so the degree of that vertex is 2 (2 edges connected to vertex), following
preconditions are activated

Line[55]:
  CGAL_precondition( !lTopFaceExists    || (lTopFaceExists    && (
pt->vertex()->vertex_degree() > 2 ) ) ) ;
  CGAL_precondition( !lBottomFaceExists || (lBottomFaceExists && (
qb->vertex()->vertex_degree() > 2 ) ) ) ;

* In my opinion this geometry is okay, and it shouldn't affect simplification,
because both edges are part of border (== not selected for simplification).
* Similar bug is located (most likely) in polyhedron_3::is_valid() too.

Quick fix:
* Add equality for testing of degree of vertex

Lehtonen, Matti

Researcher, head programmer - Helsinki Institute for Information Technology 
HIIT
http://www.hiit.fi/
-- 
Life is complex. It has real and imaginary parts.