ecency-mobile/ios/Pods/boost-for-react-native/boost/geometry/views/box_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_BOX_VIEW_HPP
#define BOOST_GEOMETRY_VIEWS_BOX_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 box behave like a ring or a range
\details Adapts a box to the Boost.Range concept, enabling the user to iterating
box corners. The box_view is registered as a Ring Concept
\tparam Box \tparam_geometry{Box}
\tparam Clockwise If true, walks in clockwise direction, otherwise
it walks in counterclockwise direction
\ingroup views
\qbk{before.synopsis,
[heading Model of]
[link geometry.reference.concepts.concept_ring Ring Concept]
}
\qbk{[include reference/views/box_view.qbk]}
*/
template <typename Box, bool Clockwise = true>
struct box_view
: public detail::points_view
<
typename geometry::point_type<Box>::type,
5
>
{
typedef typename geometry::point_type<Box>::type point_type;
/// Constructor accepting the box to adapt
explicit box_view(Box const& box)
: detail::points_view<point_type, 5>(copy_policy(box))
{}
private :
class copy_policy
{
public :
inline copy_policy(Box const& box)
: m_box(box)
{}
inline void apply(point_type* points) const
{
// assign_box_corners_oriented requires a range
// an alternative for this workaround would be to pass a range here,
// e.g. use boost::array in points_view instead of c-array
std::pair<point_type*, point_type*> rng = std::make_pair(points, points + 5);
detail::assign_box_corners_oriented<!Clockwise>(m_box, rng);
points[4] = points[0];
}
private :
Box const& m_box;
};
};
#ifndef DOXYGEN_NO_TRAITS_SPECIALIZATIONS
// All views on boxes are handled as rings
namespace traits
{
template<typename Box, bool Clockwise>
struct tag<box_view<Box, Clockwise> >
{
typedef ring_tag type;
};
template<typename Box>
struct point_order<box_view<Box, false> >
{
static order_selector const value = counterclockwise;
};
template<typename Box>
struct point_order<box_view<Box, true> >
{
static order_selector const value = clockwise;
};
}
#endif // DOXYGEN_NO_TRAITS_SPECIALIZATIONS
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_VIEWS_BOX_VIEW_HPP