strategies/distance/backward_compatibility.hpp

0001 // Boost.Geometry
0002
0003 // Copyright (c) 2021, Oracle and/or its affiliates.
0004
0005 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
0006
0007 // Licensed under the Boost Software License version 1.0.
0008 // http://www.boost.org/users/license.html
0009
0010 #ifndef BOOST_GEOMETRY_STRATEGIES_DISTANCE_BACKWARD_COMPATIBILITY_HPP
0011 #define BOOST_GEOMETRY_STRATEGIES_DISTANCE_BACKWARD_COMPATIBILITY_HPP
0012
0013
0014 #include <boost/geometry/strategies/distance/cartesian.hpp>
0015 #include <boost/geometry/strategies/distance/comparable.hpp>
0016 #include <boost/geometry/strategies/distance/detail.hpp>
0017 #include <boost/geometry/strategies/distance/geographic.hpp>
0018 #include <boost/geometry/strategies/distance/spherical.hpp>
0019
0020
0021 namespace boost { namespace geometry
0022 {
0023
0024 namespace strategies { namespace distance
0025 {
0026
0027 #ifndef DOXYGEN_NO_DETAIL
0028 namespace detail
0029 {
0030
0031 template
0032 <
0033     typename Strategy,
0034     typename CSTag,
0035     typename StrategyTag = typename strategy::distance::services::tag<Strategy>::type
0036 >
0037 struct custom_strategy
0038 {
0039     BOOST_GEOMETRY_STATIC_ASSERT_FALSE(
0040         "Not implemented for this Strategy.",
0041         Strategy);
0042 };
0043
0044 // NOTES:
0045 // - There is no guarantee that any of the custom strategies are compatible with other
0046 //   strategies.
0047 // - In many cases it is not possible to pass the custom strategy into other strategies.
0048 // - The old backward compatibility code creating default Pt/Seg strategy from custom
0049 //   Pt/Pt strategy worked the same way. The custom strategy is default-created.
0050 // - There are two versions of algorithm for Polyseg/Box, one for Seg/Box strategy the
0051 //   other one for Pt/Seg strategy. However there is only one version of algorithm for
0052 //   Seg/Box taking Seg/Box strategy.
0053 // - Geographic strategies are default-created which means WGS84 spheroid is used.
0054 // - Currently only Pt/Pt custom strategies are supported because this is what the old
0055 //   backward compatibility code was addressing.
0056
0057 template <typename Strategy>
0058 struct custom_strategy<Strategy, cartesian_tag, strategy_tag_distance_point_point>
0059     : cartesian<>
0060 {
0061     custom_strategy(Strategy const& strategy)
0062         : m_strategy(strategy)
0063     {}
0064
0065     template <typename Geometry1, typename Geometry2>
0066     auto distance(Geometry1 const&, Geometry2 const&,
0067                   enable_if_pp_t<Geometry1, Geometry2> * = nullptr) const
0068     {
0069         return m_strategy;
0070     }
0071
0072     template <typename Geometry1, typename Geometry2>
0073     auto distance(Geometry1 const&, Geometry2 const&,
0074                   enable_if_ps_t<Geometry1, Geometry2> * = nullptr) const
0075     {
0076         return strategy::distance::projected_point<void, Strategy>();
0077     }
0078
0079     template <typename Geometry1, typename Geometry2>
0080     auto distance(Geometry1 const&, Geometry2 const&,
0081                   enable_if_pb_t<Geometry1, Geometry2> * = nullptr) const
0082     {
0083         return strategy::distance::pythagoras_point_box<>();
0084     }
0085
0086     template <typename Geometry1, typename Geometry2>
0087     auto distance(Geometry1 const&, Geometry2 const&,
0088                   enable_if_sb_t<Geometry1, Geometry2> * = nullptr) const
0089     {
0090         return strategy::distance::cartesian_segment_box<void, Strategy>();
0091     }
0092
0093     template <typename Geometry1, typename Geometry2>
0094     auto distance(Geometry1 const&, Geometry2 const&,
0095                   enable_if_bb_t<Geometry1, Geometry2> * = nullptr) const
0096     {
0097         return strategy::distance::pythagoras_box_box<>();
0098     }
0099
0100 private:
0101     Strategy const& m_strategy;
0102 };
0103
0104 template <typename Strategy>
0105 struct custom_strategy<Strategy, spherical_tag, strategy_tag_distance_point_point>
0106     : detail::spherical<void, void>
0107 {
0108     custom_strategy(Strategy const& strategy)
0109         : m_strategy(strategy)
0110     {}
0111
0112     template <typename Geometry1, typename Geometry2>
0113     auto distance(Geometry1 const&, Geometry2 const&,
0114                   enable_if_pp_t<Geometry1, Geometry2> * = nullptr) const
0115     {
0116         return m_strategy;
0117     }
0118
0119     template <typename Geometry1, typename Geometry2>
0120     auto distance(Geometry1 const&, Geometry2 const&,
0121                   enable_if_ps_t<Geometry1, Geometry2> * = nullptr) const
0122     {
0123         return strategy::distance::cross_track<void, Strategy>(m_strategy);
0124     }
0125
0126     template <typename Geometry1, typename Geometry2>
0127     auto distance(Geometry1 const&, Geometry2 const&,
0128                   enable_if_pb_t<Geometry1, Geometry2> * = nullptr) const
0129     {
0130         return strategy::distance::cross_track_point_box<void, Strategy>(m_strategy);
0131     }
0132
0133     template <typename Geometry1, typename Geometry2>
0134     auto distance(Geometry1 const&, Geometry2 const&,
0135                   enable_if_sb_t<Geometry1, Geometry2> * = nullptr) const
0136     {
0137         return strategy::distance::spherical_segment_box<void, Strategy>(m_strategy);
0138     }
0139
0140     template <typename Geometry1, typename Geometry2>
0141     auto distance(Geometry1 const&, Geometry2 const&,
0142                   enable_if_bb_t<Geometry1, Geometry2> * = nullptr) const
0143     {
0144         return strategy::distance::cross_track_box_box<void, Strategy>(m_strategy);
0145     }
0146
0147 private:
0148     Strategy const& m_strategy;
0149 };
0150
0151 template <typename Strategy>
0152 struct custom_strategy<Strategy, geographic_tag, strategy_tag_distance_point_point>
0153     : geographic<>
0154 {
0155     custom_strategy(Strategy const& strategy)
0156         : m_strategy(strategy)
0157     {}
0158
0159     template <typename Geometry1, typename Geometry2>
0160     auto distance(Geometry1 const&, Geometry2 const&,
0161                   enable_if_pp_t<Geometry1, Geometry2> * = nullptr) const
0162     {
0163         return m_strategy;
0164     }
0165
0166     template <typename Geometry1, typename Geometry2>
0167     auto distance(Geometry1 const&, Geometry2 const&,
0168                   enable_if_ps_t<Geometry1, Geometry2> * = nullptr) const
0169     {
0170         return strategy::distance::geographic_cross_track<>();
0171     }
0172
0173     template <typename Geometry1, typename Geometry2>
0174     auto distance(Geometry1 const&, Geometry2 const&,
0175                   enable_if_pb_t<Geometry1, Geometry2> * = nullptr) const
0176     {
0177         return strategy::distance::geographic_cross_track_point_box<>();
0178     }
0179
0180     template <typename Geometry1, typename Geometry2>
0181     auto distance(Geometry1 const&, Geometry2 const&,
0182                   enable_if_sb_t<Geometry1, Geometry2> * = nullptr) const
0183     {
0184         return strategy::distance::geographic_segment_box<>();
0185     }
0186
0187     template <typename Geometry1, typename Geometry2>
0188     auto distance(Geometry1 const&, Geometry2 const&,
0189                   enable_if_bb_t<Geometry1, Geometry2> * = nullptr) const
0190     {
0191         return strategy::distance::geographic_cross_track_box_box<>();
0192     }
0193
0194 private:
0195     Strategy const& m_strategy;
0196 };
0197
0198 } // namespace detail
0199 #endif // DOXYGEN_NO_DETAIL
0200
0201 namespace services
0202 {
0203
0204 template <typename Geometry1, typename Geometry2, typename Strategy>
0205 struct custom_strategy_converter<Geometry1, Geometry2, Strategy, cartesian_tag, cartesian_tag>
0206 {
0207     static auto get(Strategy const& strategy)
0208     {
0209         return detail::custom_strategy<Strategy, cartesian_tag>(strategy);
0210     }
0211 };
0212
0213 template <typename Geometry1, typename Geometry2, typename Strategy>
0214 struct custom_strategy_converter<Geometry1, Geometry2, Strategy, spherical_equatorial_tag, spherical_equatorial_tag>
0215 {
0216     static auto get(Strategy const& strategy)
0217     {
0218         return detail::custom_strategy<Strategy, spherical_tag>(strategy);
0219     }
0220 };
0221
0222 template <typename Geometry1, typename Geometry2, typename Strategy>
0223 struct custom_strategy_converter<Geometry1, Geometry2, Strategy, geographic_tag, geographic_tag>
0224 {
0225     static auto get(Strategy const& strategy)
0226     {
0227         return detail::custom_strategy<Strategy, geographic_tag>(strategy);
0228     }
0229 };
0230
0231
0232 } // namespace services
0233
0234 }} // namespace strategies::distance
0235
0236 }} // namespace boost::geometry
0237
0238 #endif // BOOST_GEOMETRY_STRATEGIES_DISTANCE_BACKWARD_COMPATIBILITY_HPP