cgal/Triangulation/include/CGAL/internal/Triangulation/Triangulation_ds_iterators.h

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// Copyright (c) 2009-2014 INRIA Sophia-Antipolis (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.
//
// $URL$
// $Id$
// SPDX-License-Identifier: GPL-3.0+
//
// Author(s) : Samuel Hornus (Well... `copy, paste and hack' of Monique Teillaud's work)
#ifndef CGAL_INTERNAL_TRIANGULATION_TRIANGULATION_DS_ITERATORS_H
#define CGAL_INTERNAL_TRIANGULATION_TRIANGULATION_DS_ITERATORS_H
#include <CGAL/license/Triangulation.h>
namespace CGAL {
namespace internal {
namespace Triangulation {
template< typename TDS >
class Triangulation_ds_facet_iterator
{
typedef typename TDS::Full_cell_handle Full_cell_handle;
typedef typename TDS::Facet Facet;
typedef Facet value_type;
typedef const Facet * pointer;
typedef const Facet & reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef std::bidirectional_iterator_tag iterator_category;
typedef Triangulation_ds_facet_iterator<TDS> Facet_iterator;
TDS & tds_;
Facet ft_;
const int cur_dim_;
public:
Triangulation_ds_facet_iterator(TDS & tds)
: tds_(tds), ft_(tds.full_cells_begin(), 0), cur_dim_(tds.current_dimension())
{
CGAL_assertion( cur_dim_ > 0 );
while( ! canonical() )
raw_increment();
}
Triangulation_ds_facet_iterator(TDS & tds, int)
: tds_(tds), ft_(tds.full_cells_end(), 0), cur_dim_(tds.current_dimension())
{
CGAL_assertion( cur_dim_ > 0 );
CGAL_assertion( canonical() );
}
Facet_iterator & operator++()
{
increment();
return (*this);
}
Facet_iterator operator++(int)
{
Facet_iterator tmp(*this);
increment();
return tmp;
}
Facet_iterator & operator--()
{
decrement();
return (*this);
}
Facet_iterator operator--(int)
{
Facet_iterator tmp(*this);
decrement();
return tmp;
}
bool operator==(const Facet_iterator & fi) const
{
return (&tds_ == &fi.tds_) &&
(tds_.index_of_covertex(ft_) == fi.tds_.index_of_covertex(fi.ft_)) &&
(tds_.full_cell(ft_) == fi.tds_.full_cell(fi.ft_));
}
bool operator!=(const Facet_iterator & fi) const
{
return !(*this == fi);
}
reference operator*() const
{
return ft_;
}
pointer operator->() const
{
return &ft_;
}
private:
bool canonical()
{
if( tds_.full_cells_end() == tds_.full_cell(ft_) )
return ( 0 == tds_.index_of_covertex(ft_) );
return ( tds_.full_cell(ft_) <
tds_.full_cell(ft_)->neighbor(tds_.index_of_covertex(ft_)) );
}
void raw_decrement()
{
int i = tds_.index_of_covertex(ft_);
if( i == 0 )
ft_ = Facet(--tds_.full_cell(ft_), cur_dim_);
else
ft_ = Facet(tds_.full_cell(ft_), i - 1);
}
void raw_increment()
{
int i = tds_.index_of_covertex(ft_);
if( i == cur_dim_ )
ft_ = Facet(++tds_.full_cell(ft_), 0);
else
ft_ = Facet(tds_.full_cell(ft_), i + 1);
}
void decrement()
{
do { raw_decrement(); } while( ! canonical() );
}
void increment()
{
do { raw_increment(); } while( ! canonical() );
}
};
} // namespace Triangulation
} // namespace internal
} //namespace CGAL
#endif // CGAL_INTERNAL_TRIANGULATION_TRIANGULATION_DS_ITERATORS_H