Chris@16: // Boost.Geometry (aka GGL, Generic Geometry Library)
Chris@16: 
Chris@101: // Copyright (c) 2007-2014 Barend Gehrels, Amsterdam, the Netherlands.
Chris@101: // Copyright (c) 2008-2014 Bruno Lalande, Paris, France.
Chris@101: // Copyright (c) 2009-2014 Mateusz Loskot, London, UK.
Chris@101: 
Chris@101: // This file was modified by Oracle on 2014, 2015.
Chris@101: // Modifications copyright (c) 2014-2015, Oracle and/or its affiliates.
Chris@101: 
Chris@101: // Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
Chris@101: // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
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_ALGORITHMS_LENGTH_HPP
Chris@16: #define BOOST_GEOMETRY_ALGORITHMS_LENGTH_HPP
Chris@16: 
Chris@16: #include <iterator>
Chris@16: 
Chris@16: #include <boost/concept_check.hpp>
Chris@101: #include <boost/core/ignore_unused.hpp>
Chris@16: #include <boost/range.hpp>
Chris@16: 
Chris@16: #include <boost/mpl/fold.hpp>
Chris@16: #include <boost/mpl/greater.hpp>
Chris@16: #include <boost/mpl/if.hpp>
Chris@16: #include <boost/mpl/insert.hpp>
Chris@16: #include <boost/mpl/int.hpp>
Chris@16: #include <boost/mpl/set.hpp>
Chris@16: #include <boost/mpl/size.hpp>
Chris@16: #include <boost/mpl/transform.hpp>
Chris@16: #include <boost/type_traits.hpp>
Chris@16: 
Chris@101: #include <boost/variant/apply_visitor.hpp>
Chris@101: #include <boost/variant/static_visitor.hpp>
Chris@101: #include <boost/variant/variant_fwd.hpp>
Chris@101: 
Chris@16: #include <boost/geometry/core/cs.hpp>
Chris@16: #include <boost/geometry/core/closure.hpp>
Chris@101: #include <boost/geometry/core/tags.hpp>
Chris@16: 
Chris@16: #include <boost/geometry/geometries/concepts/check.hpp>
Chris@16: 
Chris@16: #include <boost/geometry/algorithms/assign.hpp>
Chris@16: #include <boost/geometry/algorithms/detail/calculate_null.hpp>
Chris@101: #include <boost/geometry/algorithms/detail/multi_sum.hpp>
Chris@16: // #include <boost/geometry/algorithms/detail/throw_on_empty_input.hpp>
Chris@16: #include <boost/geometry/views/closeable_view.hpp>
Chris@16: #include <boost/geometry/strategies/distance.hpp>
Chris@16: #include <boost/geometry/strategies/default_length_result.hpp>
Chris@16: 
Chris@16: 
Chris@16: namespace boost { namespace geometry
Chris@16: {
Chris@16: 
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_DETAIL
Chris@16: namespace detail { namespace length
Chris@16: {
Chris@16: 
Chris@16: 
Chris@16: template<typename Segment>
Chris@16: struct segment_length
Chris@16: {
Chris@16:     template <typename Strategy>
Chris@16:     static inline typename default_length_result<Segment>::type apply(
Chris@16:             Segment const& segment, Strategy const& strategy)
Chris@16:     {
Chris@101:         boost::ignore_unused(strategy);
Chris@16:         typedef typename point_type<Segment>::type point_type;
Chris@16:         point_type p1, p2;
Chris@16:         geometry::detail::assign_point_from_index<0>(segment, p1);
Chris@16:         geometry::detail::assign_point_from_index<1>(segment, p2);
Chris@16:         return strategy.apply(p1, p2);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: /*!
Chris@16: \brief Internal, calculates length of a linestring using iterator pairs and
Chris@16:     specified strategy
Chris@16: \note for_each could be used here, now that point_type is changed by boost
Chris@16:     range iterator
Chris@16: */
Chris@16: template<typename Range, closure_selector Closure>
Chris@16: struct range_length
Chris@16: {
Chris@16:     typedef typename default_length_result<Range>::type return_type;
Chris@16: 
Chris@16:     template <typename Strategy>
Chris@16:     static inline return_type apply(
Chris@16:             Range const& range, Strategy const& strategy)
Chris@16:     {
Chris@101:         boost::ignore_unused(strategy);
Chris@16:         typedef typename closeable_view<Range const, Closure>::type view_type;
Chris@16:         typedef typename boost::range_iterator
Chris@16:             <
Chris@16:                 view_type const
Chris@16:             >::type iterator_type;
Chris@16: 
Chris@16:         return_type sum = return_type();
Chris@16:         view_type view(range);
Chris@16:         iterator_type it = boost::begin(view), end = boost::end(view);
Chris@16:         if(it != end)
Chris@16:         {
Chris@16:             for(iterator_type previous = it++;
Chris@16:                     it != end;
Chris@16:                     ++previous, ++it)
Chris@16:             {
Chris@16:                 // Add point-point distance using the return type belonging
Chris@16:                 // to strategy
Chris@16:                 sum += strategy.apply(*previous, *it);
Chris@16:             }
Chris@16:         }
Chris@16: 
Chris@16:         return sum;
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: }} // namespace detail::length
Chris@16: #endif // DOXYGEN_NO_DETAIL
Chris@16: 
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_DISPATCH
Chris@16: namespace dispatch
Chris@16: {
Chris@16: 
Chris@16: 
Chris@16: template <typename Geometry, typename Tag = typename tag<Geometry>::type>
Chris@16: struct length : detail::calculate_null
Chris@16: {
Chris@16:     typedef typename default_length_result<Geometry>::type return_type;
Chris@16: 
Chris@16:     template <typename Strategy>
Chris@16:     static inline return_type apply(Geometry const& geometry, Strategy const& strategy)
Chris@16:     {
Chris@16:         return calculate_null::apply<return_type>(geometry, strategy);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: template <typename Geometry>
Chris@16: struct length<Geometry, linestring_tag>
Chris@16:     : detail::length::range_length<Geometry, closed>
Chris@16: {};
Chris@16: 
Chris@16: 
Chris@16: // RING: length is currently 0; it might be argued that it is the "perimeter"
Chris@16: 
Chris@16: 
Chris@16: template <typename Geometry>
Chris@16: struct length<Geometry, segment_tag>
Chris@16:     : detail::length::segment_length<Geometry>
Chris@16: {};
Chris@16: 
Chris@16: 
Chris@101: template <typename MultiLinestring>
Chris@101: struct length<MultiLinestring, multi_linestring_tag> : detail::multi_sum
Chris@101: {
Chris@101:     template <typename Strategy>
Chris@101:     static inline typename default_length_result<MultiLinestring>::type
Chris@101:     apply(MultiLinestring const& multi, Strategy const& strategy)
Chris@101:     {
Chris@101:         return multi_sum::apply
Chris@101:                <
Chris@101:                    typename default_length_result<MultiLinestring>::type,
Chris@101:                    detail::length::range_length
Chris@101:                    <
Chris@101:                        typename boost::range_value<MultiLinestring>::type,
Chris@101:                        closed // no need to close it explicitly
Chris@101:                    >
Chris@101:                >(multi, strategy);
Chris@101: 
Chris@101:     }
Chris@101: };
Chris@101: 
Chris@101: 
Chris@101: } // namespace dispatch
Chris@101: #endif // DOXYGEN_NO_DISPATCH
Chris@101: 
Chris@101: 
Chris@101: namespace resolve_variant {
Chris@101: 
Chris@16: template <typename Geometry>
Chris@101: struct length
Chris@16: {
Chris@16:     template <typename Strategy>
Chris@101:     static inline typename default_length_result<Geometry>::type
Chris@101:     apply(Geometry const& geometry, Strategy const& strategy)
Chris@16:     {
Chris@101:         return dispatch::length<Geometry>::apply(geometry, strategy);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
Chris@101: struct length<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
Chris@16: {
Chris@101:     typedef typename default_length_result
Chris@101:         <
Chris@101:             boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>
Chris@101:         >::type result_type;
Chris@16: 
Chris@16:     template <typename Strategy>
Chris@16:     struct visitor
Chris@16:         : static_visitor<result_type>
Chris@16:     {
Chris@16:         Strategy const& m_strategy;
Chris@16: 
Chris@16:         visitor(Strategy const& strategy)
Chris@16:             : m_strategy(strategy)
Chris@16:         {}
Chris@16: 
Chris@16:         template <typename Geometry>
Chris@101:         inline typename default_length_result<Geometry>::type
Chris@16:         operator()(Geometry const& geometry) const
Chris@16:         {
Chris@101:             return length<Geometry>::apply(geometry, m_strategy);
Chris@16:         }
Chris@16:     };
Chris@16: 
Chris@16:     template <typename Strategy>
Chris@16:     static inline result_type apply(
Chris@16:         variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry,
Chris@16:         Strategy const& strategy
Chris@16:     )
Chris@16:     {
Chris@16:         return apply_visitor(visitor<Strategy>(strategy), geometry);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@101: } // namespace resolve_variant
Chris@16: 
Chris@16: 
Chris@16: /*!
Chris@16: \brief \brief_calc{length}
Chris@16: \ingroup length
Chris@16: \details \details_calc{length, length (the sum of distances between consecutive points)}. \details_default_strategy
Chris@16: \tparam Geometry \tparam_geometry
Chris@16: \param geometry \param_geometry
Chris@16: \return \return_calc{length}
Chris@16: 
Chris@16: \qbk{[include reference/algorithms/length.qbk]}
Chris@16: \qbk{[length] [length_output]}
Chris@16:  */
Chris@16: template<typename Geometry>
Chris@101: inline typename default_length_result<Geometry>::type
Chris@16: length(Geometry const& geometry)
Chris@16: {
Chris@16:     concept::check<Geometry const>();
Chris@16: 
Chris@16:     // detail::throw_on_empty_input(geometry);
Chris@16: 
Chris@101:     // TODO put this into a resolve_strategy stage
Chris@16:     typedef typename strategy::distance::services::default_strategy
Chris@16:         <
Chris@101:             point_tag, point_tag, typename point_type<Geometry>::type
Chris@16:         >::type strategy_type;
Chris@16: 
Chris@101:     return resolve_variant::length<Geometry>::apply(geometry, strategy_type());
Chris@16: }
Chris@16: 
Chris@16: 
Chris@16: /*!
Chris@16: \brief \brief_calc{length} \brief_strategy
Chris@16: \ingroup length
Chris@16: \details \details_calc{length, length (the sum of distances between consecutive points)} \brief_strategy. \details_strategy_reasons
Chris@16: \tparam Geometry \tparam_geometry
Chris@16: \tparam Strategy \tparam_strategy{distance}
Chris@16: \param geometry \param_geometry
Chris@16: \param strategy \param_strategy{distance}
Chris@16: \return \return_calc{length}
Chris@16: 
Chris@16: \qbk{distinguish,with strategy}
Chris@16: \qbk{[include reference/algorithms/length.qbk]}
Chris@16: \qbk{[length_with_strategy] [length_with_strategy_output]}
Chris@16:  */
Chris@16: template<typename Geometry, typename Strategy>
Chris@101: inline typename default_length_result<Geometry>::type
Chris@16: length(Geometry const& geometry, Strategy const& strategy)
Chris@16: {
Chris@16:     concept::check<Geometry const>();
Chris@16: 
Chris@16:     // detail::throw_on_empty_input(geometry);
Chris@101: 
Chris@101:     return resolve_variant::length<Geometry>::apply(geometry, strategy);
Chris@16: }
Chris@16: 
Chris@16: 
Chris@16: }} // namespace boost::geometry
Chris@16: 
Chris@16: #endif // BOOST_GEOMETRY_ALGORITHMS_LENGTH_HPP