CGAL users discussion list

[Nico Kruithof <>]

Hi Bill,

Thanks for reporting the bug. Attached is a fix for your problem. You
can simply replace the existing file in the CGAL-include directory.

Please let me know if encounter other problems.

Bests,
Nico


 wrote:
> Hi,
> 
> I'm using Visual Studio 2005, with the static multi-thread libraries and am 
> having trouble with the program union_of_balls_subdiv in the Skin_Surface_3 
> example directory.
> 
> Program compiles and runs without errors.  It produces output to the 
> console, showing the union_of_balls verbose output is working, but the 
> "output.txt" file it creates is an empty OFF file.  The same thing happens 
> if I call Skin_Surface_3 with a shrink size of 1.0 which supposedly does 
> the same thing as union_of_balls_3 according to the manual.  Am I doing 
> something wrong?
> 
> Bill
// Copyright (c) 2005 Rijksuniversiteit Groningen (Netherlands)
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you may redistribute it under
// the terms of the Q Public License version 1.0.
// See the file LICENSE.QPL distributed with CGAL.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL: svn+ssh://scm.gforge.inria.fr/svn/cgal/branches/CGAL-3.3-branch/Skin_surface_3/include/CGAL/Triangulated_mixed_complex_observer_3.h $
// $Id: Triangulated_mixed_complex_observer_3.h 36061 2007-02-06 08:17:14Z nicokruithof $
// 
//
// Author(s)     : Nico Kruithof <>

#ifndef CGAL_TRIANGULATED_MIXED_COMPLEX_OBSERVER_3
#define CGAL_TRIANGULATED_MIXED_COMPLEX_OBSERVER_3

#include <CGAL/Triangulation_simplex_3.h>
#include <CGAL/Skin_surface_quadratic_surface_3.h>

CGAL_BEGIN_NAMESPACE

template <class T>
struct SS_Dereference_type {
  typedef T value_type;
};
template <class T>
struct SS_Dereference_type<T *> {
  typedef T value_type;
};

template <class TriangulatedMixedComplex_3,
          class SkinSurface_3>
class Triangulated_mixed_complex_observer_3 {
public:
  typedef typename SkinSurface_3::Regular            Regular;
  typedef typename Regular::Geom_traits              Regular_traits;
  typedef TriangulatedMixedComplex_3                 Triangulated_mixed_complex;
  typedef typename Triangulated_mixed_complex::Geom_traits
                                  Triangulated_mixed_complex_traits;
  typedef typename Triangulated_mixed_complex::Triangulation_data_structure
                                                     TMC_TDS;
  typedef typename SkinSurface_3::Quadratic_surface  Quadratic_surface;

  typedef typename Regular_traits::FT                FT;

  typedef typename Regular::Vertex_handle            Rt_Vertex_handle;
  typedef typename Regular::Edge                     Rt_Edge;
  typedef typename Regular::Facet                    Rt_Facet;
  typedef typename Regular::Cell_handle              Rt_Cell_handle;
  typedef Triangulation_simplex_3<Regular>           Rt_Simplex;

  typedef typename Regular::Bare_point               Rt_Point;
  typedef typename Regular::Geom_traits              Rt_Geom_traits;
  typedef typename Rt_Geom_traits::RT                Rt_RT;
  typedef typename Regular::Weighted_point           Rt_Weighted_point;

  typedef typename Triangulated_mixed_complex::Vertex_handle TMC_Vertex_handle;
  typedef typename Triangulated_mixed_complex::Cell_handle   TMC_Cell_handle;
  

  typedef typename Quadratic_surface::K               Surface_traits;
  typedef typename Surface_traits::RT                 Surface_RT;
  typedef Regular_triangulation_euclidean_traits_3<Surface_traits> Surface_regular_traits;
  typedef typename Quadratic_surface::Point               Surface_point;
  typedef typename Quadratic_surface::Vector              Surface_vector;
  typedef Weighted_point<Surface_point,Surface_RT>   Surface_weighted_point;

  typedef Weighted_converter_3< 
    Cartesian_converter < typename Regular_traits::Bare_point::R, 
			  typename Quadratic_surface::K > >            R2S_converter;
  Triangulated_mixed_complex_observer_3(FT shrink) : 
    shrink(shrink) {
  }

  void after_vertex_insertion(Rt_Simplex const &sDel, 
                              Rt_Simplex const &sVor, 
                              TMC_Vertex_handle &vh) 
  {
    vh->info() = typename SkinSurface_3::Vertex_info(sDel, sVor);
  }

  void after_cell_insertion(Rt_Simplex const &s, TMC_Cell_handle &ch)  
  {
    if (!(s == prev_s)) {
      prev_s = s;
      Rt_Vertex_handle vh;
      Rt_Edge          e;
      Rt_Facet         f;
      Rt_Cell_handle   ch;
      
      switch (s.dimension()) {
        case 0:
      	{
      	  vh = s;
          Surface_weighted_point wp = r2s_converter(vh->point());
      	  create_sphere(wp.point(), -wp.weight(), shrink, 1);
      	  break;
      	}
        case 1:
      	{
      	  e = s;
      	  Surface_weighted_point p0 = 
      	    r2s_converter(e.first->vertex(e.second)->point());
      	  Surface_weighted_point p1 = 
      	    r2s_converter(e.first->vertex(e.third)->point());
      	  
      	  create_hyperboloid
      	    (typename Surface_regular_traits::
      	     Construct_weighted_circumcenter_3()(p0,p1),
      	     typename Surface_regular_traits::
      	     Compute_squared_radius_smallest_orthogonal_sphere_3()(p0,p1),
      	     p0 - p1,
      	     shrink,
      	     1);
      	  break;
      	}
        case 2:
      	{
      	  f = s;
      	  Surface_weighted_point p0 = 
      	    r2s_converter(f.first->vertex((f.second+1)&3)->point());
      	  Surface_weighted_point p1 = 
      	    r2s_converter(f.first->vertex((f.second+2)&3)->point());
      	  Surface_weighted_point p2 = 
      	    r2s_converter(f.first->vertex((f.second+3)&3)->point());
      	  
      	  create_hyperboloid
      	    (typename Surface_regular_traits::
      	     Construct_weighted_circumcenter_3()(p0,p1,p2),
      	     typename Surface_regular_traits::
      	     Compute_squared_radius_smallest_orthogonal_sphere_3()(p0,p1,p2),
      	     typename Surface_regular_traits::
      	     Construct_orthogonal_vector_3()(p0,p1,p2),
      	     1-shrink,
      	     -1);
      	  break;
      	}
        case 3:
      	{
      	  ch = s;
          const Surface_weighted_point pts[4] = 
            { r2s_converter(ch->vertex(0)->point()),
              r2s_converter(ch->vertex(1)->point()),
              r2s_converter(ch->vertex(2)->point()),
              r2s_converter(ch->vertex(3)->point()) };
          
      	  create_sphere
      	    (typename Surface_regular_traits::
      	       Construct_weighted_circumcenter_3()
                 (pts[0],pts[1],pts[2],pts[3]),
      	     typename Surface_regular_traits::
      	       Compute_squared_radius_smallest_orthogonal_sphere_3()
                 (pts[0],pts[1],pts[2],pts[3]),
      	     1-shrink,
      	     -1);
      	}
      }
    }
    ch->info() = typename SkinSurface_3::Cell_info(s,surf);
  }

  FT shrink;
  Rt_Simplex prev_s;
  Quadratic_surface *surf;

  // c is the center of the orthogonal sphere
  // w is the weight of the orthogonal sphere
  // s is the shrink factor
  // orient is the orientation of the sphere
  void create_sphere(const Surface_point &c,
		     const Surface_RT &w,
		     const Surface_RT &s,
		     const int orient) {
    Q[1] = Q[3] = Q[4] = 0;
    Q[0] = Q[2] = Q[5] = orient;
    
    surf = new Quadratic_surface(Q, c, s*w, (orient==1? 0 : 3));
  }

  void create_hyperboloid(const Surface_point &c,
			  const Surface_RT &w,
			  const Surface_vector &t,
			  const Surface_RT &s,
			  const int orient) {
    Surface_RT den = t*t;
    
    Q[0] = orient*(-  t.x()*t.x()/den + (1-s));
    
    Q[1] = orient*(-2*t.y()*t.x()/den);
    Q[2] = orient*(-  t.y()*t.y()/den + (1-s));
    
    Q[3] = orient*(-2*t.z()*t.x()/den);
    Q[4] = orient*(-2*t.z()*t.y()/den);
    Q[5] = orient*(-  t.z()*t.z()/den + (1-s));
    
    surf = new Quadratic_surface(Q, c, s*(1-s)*w, (orient==1? 1 : 2));
  }

  Surface_RT Q[6];
  R2S_converter r2s_converter;
};

CGAL_END_NAMESPACE

#endif // CGAL_TRIANGULATED_MIXED_COMPLEX_OBSERVER_3