Chris@16: // Boost.Geometry (aka GGL, Generic Geometry Library)
Chris@16: 
Chris@16: // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
Chris@16: // Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
Chris@16: // Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
Chris@16: 
Chris@16: // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
Chris@16: // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
Chris@16: 
Chris@16: // Use, modification and distribution is subject to the Boost Software License,
Chris@16: // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_GEOMETRY_VIEWS_BOX_VIEW_HPP
Chris@16: #define BOOST_GEOMETRY_VIEWS_BOX_VIEW_HPP
Chris@16: 
Chris@16: 
Chris@16: #include <boost/range.hpp>
Chris@16: 
Chris@16: #include <boost/geometry/core/point_type.hpp>
Chris@16: #include <boost/geometry/views/detail/points_view.hpp>
Chris@16: #include <boost/geometry/algorithms/assign.hpp>
Chris@16: 
Chris@16: 
Chris@16: namespace boost { namespace geometry
Chris@16: {
Chris@16: 
Chris@16: 
Chris@16: /*!
Chris@16: \brief Makes a box behave like a ring or a range
Chris@16: \details Adapts a box to the Boost.Range concept, enabling the user to iterating
Chris@16:     box corners. The box_view is registered as a Ring Concept
Chris@16: \tparam Box \tparam_geometry{Box}
Chris@16: \tparam Clockwise If true, walks in clockwise direction, otherwise
Chris@16:     it walks in counterclockwise direction
Chris@16: \ingroup views
Chris@16: 
Chris@16: \qbk{before.synopsis,
Chris@16: [heading Model of]
Chris@16: [link geometry.reference.concepts.concept_ring Ring Concept]
Chris@16: }
Chris@16: 
Chris@16: \qbk{[include reference/views/box_view.qbk]}
Chris@16: */
Chris@16: template <typename Box, bool Clockwise = true>
Chris@101: struct box_view
Chris@16:     : public detail::points_view
Chris@16:         <
Chris@101:             typename geometry::point_type<Box>::type,
Chris@16:             5
Chris@16:         >
Chris@16: {
Chris@16:     typedef typename geometry::point_type<Box>::type point_type;
Chris@101: 
Chris@16:     /// Constructor accepting the box to adapt
Chris@16:     explicit box_view(Box const& box)
Chris@16:         : detail::points_view<point_type, 5>(copy_policy(box))
Chris@16:     {}
Chris@101: 
Chris@101: private :
Chris@101: 
Chris@16:     class copy_policy
Chris@16:     {
Chris@16:     public :
Chris@16:         inline copy_policy(Box const& box)
Chris@16:             : m_box(box)
Chris@16:         {}
Chris@101: 
Chris@16:         inline void apply(point_type* points) const
Chris@16:         {
Chris@101:             // assign_box_corners_oriented requires a range
Chris@101:             // an alternative for this workaround would be to pass a range here,
Chris@101:             // e.g. use boost::array in points_view instead of c-array
Chris@101:             std::pair<point_type*, point_type*> rng = std::make_pair(points, points + 5);
Chris@101:             detail::assign_box_corners_oriented<!Clockwise>(m_box, rng);
Chris@16:             points[4] = points[0];
Chris@16:         }
Chris@16:     private :
Chris@16:         Box const& m_box;
Chris@16:     };
Chris@16: 
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_TRAITS_SPECIALIZATIONS
Chris@16: 
Chris@16: // All views on boxes are handled as rings
Chris@16: namespace traits
Chris@16: {
Chris@16: 
Chris@16: template<typename Box, bool Clockwise>
Chris@16: struct tag<box_view<Box, Clockwise> >
Chris@16: {
Chris@16:     typedef ring_tag type;
Chris@16: };
Chris@16: 
Chris@16: template<typename Box>
Chris@16: struct point_order<box_view<Box, false> >
Chris@16: {
Chris@16:     static order_selector const value = counterclockwise;
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: template<typename Box>
Chris@16: struct point_order<box_view<Box, true> >
Chris@16: {
Chris@16:     static order_selector const value = clockwise;
Chris@16: };
Chris@16: 
Chris@16: }
Chris@16: 
Chris@16: #endif // DOXYGEN_NO_TRAITS_SPECIALIZATIONS
Chris@16: 
Chris@16: 
Chris@16: }} // namespace boost::geometry
Chris@16: 
Chris@16: 
Chris@16: #endif // BOOST_GEOMETRY_VIEWS_BOX_VIEW_HPP