Chris@102: // Boost.Geometry (aka GGL, Generic Geometry Library)
Chris@102: 
Chris@102: // Copyright (c) 2014, Oracle and/or its affiliates.
Chris@102: 
Chris@102: // Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
Chris@102: 
Chris@102: // Licensed under the Boost Software License version 1.0.
Chris@102: // http://www.boost.org/users/license.html
Chris@102: 
Chris@102: #ifndef BOOST_GEOMETRY_ALGORITHMS_NUM_SEGMENTS_HPP
Chris@102: #define BOOST_GEOMETRY_ALGORITHMS_NUM_SEGMENTS_HPP
Chris@102: 
Chris@102: #include <cstddef>
Chris@102: 
Chris@102: #include <boost/mpl/size_t.hpp>
Chris@102: #include <boost/mpl/times.hpp>
Chris@102: 
Chris@102: #include <boost/range.hpp>
Chris@102: 
Chris@102: #include <boost/variant/apply_visitor.hpp>
Chris@102: #include <boost/variant/static_visitor.hpp>
Chris@102: #include <boost/variant/variant_fwd.hpp>
Chris@102: 
Chris@102: #include <boost/geometry/core/closure.hpp>
Chris@102: #include <boost/geometry/core/tag.hpp>
Chris@102: #include <boost/geometry/core/tags.hpp>
Chris@102: 
Chris@102: #include <boost/geometry/util/range.hpp>
Chris@102: 
Chris@102: #include <boost/geometry/geometries/concepts/check.hpp>
Chris@102: 
Chris@102: #include <boost/geometry/algorithms/not_implemented.hpp>
Chris@102: 
Chris@102: #include <boost/geometry/algorithms/detail/counting.hpp>
Chris@102: 
Chris@102: 
Chris@102: namespace boost { namespace geometry
Chris@102: {
Chris@102: 
Chris@102: #ifndef DOXYGEN_NO_DETAIL
Chris@102: namespace detail { namespace num_segments
Chris@102: {
Chris@102: 
Chris@102: 
Chris@102: struct range_count
Chris@102: {
Chris@102:     template <typename Range>
Chris@102:     static inline std::size_t apply(Range const& range)
Chris@102:     {
Chris@102:         std::size_t n = boost::size(range);
Chris@102:         if ( n <= 1 )
Chris@102:         {
Chris@102:             return 0;
Chris@102:         }
Chris@102: 
Chris@102:         return
Chris@102:             geometry::closure<Range>::value == open
Chris@102:             ?
Chris@102:             n
Chris@102:             :
Chris@102:             static_cast<std::size_t>(n - 1);
Chris@102:     }
Chris@102: };
Chris@102: 
Chris@102: }} // namespace detail::num_segments
Chris@102: #endif // DOXYGEN_NO_DETAIL
Chris@102: 
Chris@102: 
Chris@102: 
Chris@102: #ifndef DOXYGEN_NO_DISPATCH
Chris@102: namespace dispatch
Chris@102: {
Chris@102: 
Chris@102: template <typename Geometry, typename Tag = typename tag<Geometry>::type>
Chris@102: struct num_segments
Chris@102:     : not_implemented<Tag>
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, point_tag>
Chris@102:     : detail::counting::other_count<0>
Chris@102: {};
Chris@102: 
Chris@102: // the number of segments (1-dimensional faces) of the hypercube is
Chris@102: // given by the formula: d * 2^(d-1), where d is the dimension of the
Chris@102: // hypercube; see also:
Chris@102: //            http://en.wikipedia.org/wiki/Hypercube
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, box_tag>
Chris@102:     : detail::counting::other_count
Chris@102:         <
Chris@102:             geometry::dimension<Geometry>::value
Chris@102:             * (1 << (geometry::dimension<Geometry>::value - 1))
Chris@102:         >
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, segment_tag>
Chris@102:     : detail::counting::other_count<1>
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, linestring_tag>
Chris@102:     : detail::num_segments::range_count
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, ring_tag>
Chris@102:     : detail::num_segments::range_count
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, polygon_tag>
Chris@102:     : detail::counting::polygon_count<detail::num_segments::range_count>
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, multi_point_tag>
Chris@102:     : detail::counting::other_count<0>
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, multi_linestring_tag>
Chris@102:     : detail::counting::multi_count
Chris@102:         <
Chris@102:             num_segments< typename boost::range_value<Geometry>::type>
Chris@102:         >
Chris@102: {};
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments<Geometry, multi_polygon_tag>
Chris@102:     : detail::counting::multi_count
Chris@102:         <
Chris@102:             num_segments< typename boost::range_value<Geometry>::type>
Chris@102:         >
Chris@102: {};
Chris@102: 
Chris@102: 
Chris@102: } // namespace dispatch
Chris@102: #endif // DOXYGEN_NO_DISPATCH
Chris@102: 
Chris@102: 
Chris@102: 
Chris@102: namespace resolve_variant
Chris@102: {
Chris@102: 
Chris@102: 
Chris@102: template <typename Geometry>
Chris@102: struct num_segments
Chris@102: {
Chris@102:     static inline std::size_t apply(Geometry const& geometry)
Chris@102:     {
Chris@102:         concept::check<Geometry const>();
Chris@102: 
Chris@102:         return dispatch::num_segments<Geometry>::apply(geometry);
Chris@102:     }
Chris@102: };
Chris@102: 
Chris@102: 
Chris@102: template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
Chris@102: struct num_segments<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
Chris@102: {
Chris@102:     struct visitor: boost::static_visitor<std::size_t>
Chris@102:     {
Chris@102:         template <typename Geometry>
Chris@102:         inline std::size_t operator()(Geometry const& geometry) const
Chris@102:         {
Chris@102:             return num_segments<Geometry>::apply(geometry);
Chris@102:         }
Chris@102:     };
Chris@102: 
Chris@102:     static inline std::size_t
Chris@102:     apply(boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry)
Chris@102:     {
Chris@102:         return boost::apply_visitor(visitor(), geometry);
Chris@102:     }
Chris@102: };
Chris@102: 
Chris@102: 
Chris@102: } // namespace resolve_variant
Chris@102: 
Chris@102: 
Chris@102: 
Chris@102: /*!
Chris@102: \brief \brief_calc{number of segments}
Chris@102: \ingroup num_segments
Chris@102: \details \details_calc{num_segments, number of segments}.
Chris@102: \tparam Geometry \tparam_geometry
Chris@102: \param geometry \param_geometry
Chris@102: \return \return_calc{number of segments}
Chris@102: 
Chris@102: \qbk{[include reference/algorithms/num_segments.qbk]}
Chris@102: */
Chris@102: template <typename Geometry>
Chris@102: inline std::size_t num_segments(Geometry const& geometry)
Chris@102: {
Chris@102:     return resolve_variant::num_segments<Geometry>::apply(geometry);
Chris@102: }
Chris@102: 
Chris@102: 
Chris@102: 
Chris@102: }} // namespace boost::geometry
Chris@102: 
Chris@102: #endif // BOOST_GEOMETRY_ALGORITHMS_NUM_SEGMENTS_HPP