cgal/Polygon_mesh_processing/include/CGAL/polygon_mesh_self_intersect...

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// Copyright (c) 2008 INRIA Sophia-Antipolis (France).
// Copyright (c) 2008-2013 GeometryFactory (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
// You can redistribute it and/or modify it under the terms of the GNU
// General Public License as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// 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.
//
// $URL$
// $Id$
//
//
// Author(s) : Pierre Alliez, Laurent Rineau, Ilker O. Yaz
// compute self-intersection of a CGAL triangle polyhedron mesh
// original code from Lutz Kettner
#ifndef CGAL_POLYGON_MESH_SELF_INTERSECTIONS
#define CGAL_POLYGON_MESH_SELF_INTERSECTIONS
#include <CGAL/box_intersection_d.h>
#include <CGAL/intersections.h>
#include <CGAL/Bbox_3.h>
#include <vector>
#include <exception>
#include <boost/function_output_iterator.hpp>
#include <boost/type_traits/is_const.hpp>
#include <boost/graph/graph_traits.hpp>
#include <CGAL/boost/graph/helpers.h>
namespace CGAL {
namespace internal {
template <class TM,//TriangleMesh
class Kernel,
class Box, class OutputIterator>
struct Intersect_facets
{
// wrapper to check whether anything is inserted to output iterator
struct Output_iterator_with_bool
{
Output_iterator_with_bool(OutputIterator* out, bool* intersected)
: m_iterator(out), m_intersected(intersected) { }
template<class T>
void operator()(const T& t) {
*m_intersected = true;
*(*m_iterator)++ = t;
}
OutputIterator* m_iterator;
bool* m_intersected;
};
// typedefs
typedef typename Kernel::Segment_3 Segment;
typedef typename Kernel::Triangle_3 Triangle;
typedef typename boost::graph_traits<TM>::halfedge_descriptor halfedge_descriptor;
typedef typename boost::property_map<TM, boost::vertex_point_t>::const_type Ppmap;
// members
const TM& m_tmesh;
const Ppmap m_point;
mutable OutputIterator m_iterator;
mutable bool m_intersected;
mutable boost::function_output_iterator<Output_iterator_with_bool> m_iterator_wrapper;
typename Kernel::Construct_segment_3 segment_functor;
typename Kernel::Construct_triangle_3 triangle_functor;
typename Kernel::Do_intersect_3 do_intersect_3_functor;
Intersect_facets(const TM& tmesh, OutputIterator it, const Kernel& kernel)
:
m_tmesh(tmesh),
m_point(get(vertex_point, m_tmesh)),
m_iterator(it),
m_intersected(false),
m_iterator_wrapper(Output_iterator_with_bool(&m_iterator, &m_intersected)),
segment_functor(kernel.construct_segment_3_object()),
triangle_functor(kernel.construct_triangle_3_object()),
do_intersect_3_functor(kernel.do_intersect_3_object())
{ }
void operator()(const Box* b,
const Box* c) const
{
halfedge_descriptor h = halfedge(b->info(),m_tmesh);
// check for shared egde --> no intersection
if(face(opposite(h,m_tmesh),m_tmesh) == c->info() ||
face(opposite(next(h,m_tmesh),m_tmesh),m_tmesh) == c->info() ||
face(opposite(next(next(h,m_tmesh),m_tmesh),m_tmesh),m_tmesh) == c->info())
return;
// check for shared vertex --> maybe intersection, maybe not
halfedge_descriptor g = halfedge(c->info(),m_tmesh);
halfedge_descriptor v;
if(target(h,m_tmesh) == target(g,m_tmesh))
v = g;
if(target(h,m_tmesh) == target(next(g,m_tmesh),m_tmesh))
v = next(g,m_tmesh);
if(target(h,m_tmesh) == target(next(next(g,m_tmesh),m_tmesh),m_tmesh))
v = next(next(g,m_tmesh),m_tmesh);
if(v == halfedge_descriptor()){
h = next(h,m_tmesh);
if(target(h,m_tmesh) == target(g,m_tmesh))
v = g;
if(target(h,m_tmesh) == target(next(g,m_tmesh),m_tmesh))
v = next(g,m_tmesh);
if(target(h,m_tmesh) == target(next(next(g,m_tmesh),m_tmesh),m_tmesh))
v = next(next(g,m_tmesh),m_tmesh);
if(v == halfedge_descriptor()){
h = next(h,m_tmesh);
if(target(h,m_tmesh) == target(g,m_tmesh))
v = g;
if(target(h,m_tmesh) == target(next(g,m_tmesh),m_tmesh))
v = next(g,m_tmesh);
if(target(h,m_tmesh) == target(next(next(g,m_tmesh),m_tmesh),m_tmesh))
v = next(next(g,m_tmesh),m_tmesh);
}
}
if(v != halfedge_descriptor()){
// found shared vertex:
CGAL_assertion(target(h,m_tmesh) == target(v,m_tmesh));
// geometric check if the opposite segments intersect the triangles
Triangle t1 = triangle_functor( m_point[target(h,m_tmesh)], m_point[target(next(h,m_tmesh),m_tmesh)], m_point[target(next(next(h,m_tmesh),m_tmesh),m_tmesh)]);
Triangle t2 = triangle_functor( m_point[target(v,m_tmesh)], m_point[target(next(v,m_tmesh),m_tmesh)], m_point[target(next(next(v,m_tmesh),m_tmesh),m_tmesh)]);
Segment s1 = segment_functor( m_point[target(next(h,m_tmesh),m_tmesh)], m_point[target(next(next(h,m_tmesh),m_tmesh),m_tmesh)]);
Segment s2 = segment_functor( m_point[target(next(v,m_tmesh),m_tmesh)], m_point[target(next(next(v,m_tmesh),m_tmesh),m_tmesh)]);
if(do_intersect_3_functor(t1,s2)){
*m_iterator_wrapper++ = std::make_pair(b->info(), c->info());
} else if(do_intersect_3_functor(t2,s1)){
*m_iterator_wrapper++ = std::make_pair(b->info(), c->info());
}
return;
}
// check for geometric intersection
Triangle t1 = triangle_functor( m_point[target(h,m_tmesh)], m_point[target(next(h,m_tmesh),m_tmesh)], m_point[target(next(next(h,m_tmesh),m_tmesh),m_tmesh)]);
Triangle t2 = triangle_functor( m_point[target(g,m_tmesh)], m_point[target(next(g,m_tmesh),m_tmesh)], m_point[target(next(next(g,m_tmesh),m_tmesh),m_tmesh)]);
if(do_intersect_3_functor(t1, t2)){
*m_iterator_wrapper++ = std::make_pair(b->info(), c->info());
}
} // end operator ()
}; // end struct Intersect_facets
struct Throw_at_output {
class Throw_at_output_exception: public std::exception
{ };
template<class T>
void operator()(const T& /* t */) const {
throw Throw_at_output_exception();
}
};
}// namespace internal
namespace Polygon_mesh_processing {
/**
* \ingroup PkgPolygonMeshProcessing
* Detects and reports self-intersections of a triangulated polyhedral surface.
* Depends on \ref PkgBoxIntersectionDSummary
* @pre @a CGAL::is_pure_triangle(tmesh)
*
* @tparam GeomTraits a model of `SelfIntersectionTraits`
* @tparam TriangleMesh a model of `FaceListGraph` (possibly a \cgal polyhedron)
* @tparam OutputIterator Output iterator accepting objects of type
* `std::pair<boost::graph_traits<TriangleMesh>::face_descriptor, boost::graph_traits<TriangleMesh>::face_descriptor>`
* if @a polygon mesh is passed by const reference.
*
* @param tmesh triangle mesh to be checked, might be passed by const reference or reference
* @param out all pairs of non-adjacent facets intersecting are put in it
* @param geom_traits traits class providing intersection test primitives
*
* @return `out`
*/
template <class GeomTraits, class TriangleMesh, class OutputIterator>
OutputIterator
self_intersections(const TriangleMesh& tmesh,
OutputIterator out,
const GeomTraits& geom_traits = GeomTraits())
{
CGAL_precondition(CGAL::is_pure_triangle(tmesh));
typedef TriangleMesh TM;
typedef typename boost::graph_traits<TM>::face_iterator Facet_it;
typedef typename boost::graph_traits<TM>::face_descriptor Facet_hdl;
typedef typename CGAL::Box_intersection_d::Box_with_info_d<double, 3, Facet_hdl> Box;
typedef typename boost::property_map<TM, CGAL::vertex_point_t>::const_type Ppmap;
Ppmap m_point = get(CGAL::vertex_point, tmesh);
// make one box per facet
std::vector<Box> boxes;
boxes.reserve(num_faces(tmesh));
Facet_it fi,e;
for(boost::tie(fi,e)= faces(tmesh);
fi != e;
++fi){
Facet_hdl f = *fi;
boxes.push_back(Box( m_point[target(halfedge(f,tmesh),tmesh)].bbox() +
m_point[target(next(halfedge(f,tmesh),tmesh),tmesh)].bbox() +
m_point[target(next(next(halfedge(f,tmesh),tmesh),tmesh),tmesh)].bbox(),
f));
}
// generate box pointers
std::vector<const Box*> box_ptr;
box_ptr.reserve(num_faces(tmesh));
typename std::vector<Box>::iterator b;
for(b = boxes.begin();
b != boxes.end();
b++)
box_ptr.push_back(&*b);
// compute self-intersections filtered out by boxes
CGAL::internal::Intersect_facets<TM,GeomTraits,Box,OutputIterator> intersect_facets(tmesh, out, geom_traits);
std::ptrdiff_t cutoff = 2000;
CGAL::box_self_intersection_d(box_ptr.begin(), box_ptr.end(),intersect_facets,cutoff);
return intersect_facets.m_iterator;
}
/**
* \ingroup PkgPolygonMeshProcessing
* Checks if a polygon mesh is self-intersecting.
* Depends on \ref PkgBoxIntersectionDSummary
* @pre @a CGAL::is_pure_triangle(tmesh)
*
* @tparam GeomTraits a model of `SelfIntersectionTraits`
* @tparam TriangleMesh a model of `FaceListGraph` (possibly a %CGAL polyhedron)
*
* @param tmesh TriangleMesh to be tested
* @param geom_traits traits class providing intersection test primitives
*
* @return true if `tmesh` is self-intersecting
*/
template <class GeomTraits, class TriangleMesh>
bool is_self_intersecting(const TriangleMesh& tmesh,
const GeomTraits& geom_traits = GeomTraits())
{
CGAL_precondition(CGAL::is_pure_triangle(tmesh));
try
{
typedef boost::function_output_iterator<CGAL::internal::Throw_at_output> OutputIterator;
self_intersections<GeomTraits>(tmesh, OutputIterator(), geom_traits);
}
catch( CGAL::internal::Throw_at_output::Throw_at_output_exception& )
{ return true; }
return false;
}
}// end namespace Polygon_mesh_processing
}// namespace CGAL
#endif // CGAL_SELF_INTERSECTION_POLYHEDRON_3