dust3d/thirdparty/cgal/CGAL-5.1/include/CGAL/Interpolation/internal/helpers.h

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// Copyright (c) 2003, 2017 INRIA Sophia-Antipolis (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL: https://github.com/CGAL/cgal/blob/v5.1/Interpolation/include/CGAL/Interpolation/internal/helpers.h $
// $Id: helpers.h 254d60f 2019-10-19T15:23:19+02:00 Sébastien Loriot
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
// Author(s) : Julia Floetotto
#ifndef CGAL_INTERPOLATION_INTERNAL_HELPERS_H
#define CGAL_INTERPOLATION_INTERNAL_HELPERS_H
#include <CGAL/license/Interpolation.h>
#include <CGAL/assertions.h>
#include <utility>
namespace CGAL {
namespace Interpolation {
namespace internal {
// Extracts the bare point from a weighted point or a vertex handle (and identity
// if the argument is a bare point)
template < typename InterpolationTraits_ >
struct Extract_bare_point
{
typedef InterpolationTraits_ Traits;
typedef typename Traits::Point_d Point;
typedef typename Traits::Weighted_point_d Weighted_point;
Extract_bare_point(const Traits& traits = Traits()) : traits(traits) {}
const Point& operator()(const Point& p) const { return p; }
Point operator()(const Weighted_point& wp) const {
return traits.construct_point_d_object()(wp);
}
template <typename VH>
Point operator()(const VH& vh) const {
CGAL_precondition(vh != VH());
return traits.construct_point_d_object()(vh->point());
}
private:
Traits traits;
};
// Converts a pair<Triangulation_::Vertex_handle, T2_>
// into a pair<Triangulation_::Point, T2_>
template < typename Triangulation_, typename T2_ >
struct Extract_point_in_pair
{
typedef Triangulation_ Tr;
typedef T2_ T2;
typedef typename Tr::Vertex_handle Vertex_handle;
typedef typename Tr::Point Point; // possibly weighted
typedef std::pair<Vertex_handle, T2> argument_type;
typedef std::pair<Point, T2> result_type;
result_type operator()(const argument_type& vp) const
{
CGAL_precondition(vp.first != Vertex_handle());
return std::make_pair(vp.first->point(), vp.second);
}
};
// Given a map `m` of type `Map`, transforms an object of type `pair<Map::key_type, T2>`
// into an object of type `pair<Map::mapped_type, T2>`, using the `m`.
//
template < typename Map_, typename T2_ >
struct Pair_mapper
{
typedef Map_ Map;
typedef T2_ T2;
typedef typename Map::key_type Map_key_type;
typedef typename Map::mapped_type Map_mapped_type;
typedef std::pair<Map_key_type, T2> argument_type;
typedef std::pair<Map_mapped_type, T2> result_type;
const Map& map;
Pair_mapper(const Map& map) : map(map) {}
result_type operator()(const argument_type& vp) const
{
typename Map::const_iterator it = map.find(vp.first);
CGAL_assertion(it != map.end());
return std::make_pair(it->second, vp.second);
}
};
// The struct "Project_vertex_output_iterator" is used in natural_neighbor_coordinates_2,
// as well as in regular_neighbor_coordinates_2, and in surface_neighbor_coordinates_3.
//
// It wraps the OutputIterator with value type `std::pair<Vertex_handle, T2>`
// into an output iterator with value type `OutputFunctor::result_type`.
//
// \pre OutputIterator has value type std::pair<Vertex_handle, T>
// \pre Vertex_handle has a function ->point() with return type const Point&
// \pre OutputIterator::value_type == OutputFunctor::argument_type
template < class OutputIterator, class OutputFunctor >
struct Project_vertex_output_iterator
{
OutputIterator out;
OutputFunctor fct;
//creation:
Project_vertex_output_iterator(OutputIterator o, OutputFunctor f)
: out(o), fct(f)
{}
OutputIterator base() {return out;}
Project_vertex_output_iterator& operator++(){out++; return *this;}
Project_vertex_output_iterator& operator++(int){out++; return *this;}
Project_vertex_output_iterator& operator*(){return *this;}
template<class Vertex_pair>
Project_vertex_output_iterator& operator=(const Vertex_pair& vp)
{
*out = fct(vp);
return *this;
}
};
} // namespace internal
} // namespace Interpolation
} // namespace CGAL
#endif // CGAL_INTERPOLATION_INTERNAL_HELPERS_H