vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/geometry/views/segment_view.hpp

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// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_GEOMETRY_VIEWS_SEGMENT_VIEW_HPP
#define BOOST_GEOMETRY_VIEWS_SEGMENT_VIEW_HPP
#include <boost/range.hpp>
#include <boost/geometry/core/point_type.hpp>
#include <boost/geometry/views/detail/points_view.hpp>
#include <boost/geometry/algorithms/assign.hpp>
namespace boost { namespace geometry
{
/*!
\brief Makes a segment behave like a linestring or a range
\details Adapts a segment to the Boost.Range concept, enabling the user to
iterate the two segment points. The segment_view is registered as a LineString Concept
\tparam Segment \tparam_geometry{Segment}
\ingroup views
\qbk{before.synopsis,
[heading Model of]
[link geometry.reference.concepts.concept_linestring LineString Concept]
}
\qbk{[include reference/views/segment_view.qbk]}
*/
template <typename Segment>
struct segment_view
: public detail::points_view
<
typename geometry::point_type<Segment>::type,
2
>
{
typedef typename geometry::point_type<Segment>::type point_type;
/// Constructor accepting the segment to adapt
explicit segment_view(Segment const& segment)
: detail::points_view<point_type, 2>(copy_policy(segment))
{}
private :
class copy_policy
{
public :
inline copy_policy(Segment const& segment)
: m_segment(segment)
{}
inline void apply(point_type* points) const
{
geometry::detail::assign_point_from_index<0>(m_segment, points[0]);
geometry::detail::assign_point_from_index<1>(m_segment, points[1]);
}
private :
Segment const& m_segment;
};
};
#ifndef DOXYGEN_NO_TRAITS_SPECIALIZATIONS
// All segment ranges can be handled as linestrings
namespace traits
{
template<typename Segment>
struct tag<segment_view<Segment> >
{
typedef linestring_tag type;
};
}
#endif // DOXYGEN_NO_TRAITS_SPECIALIZATIONS
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_VIEWS_SEGMENT_VIEW_HPP