strategies/centroid/cartesian.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_CENTROID_CARTESIAN_HPP
0011 #define BOOST_GEOMETRY_STRATEGIES_CENTROID_CARTESIAN_HPP
0012
0013
0014 #include <boost/geometry/strategies/cartesian/centroid_average.hpp>
0015 #include <boost/geometry/strategies/cartesian/centroid_bashein_detmer.hpp>
0016 #include <boost/geometry/strategies/cartesian/centroid_weighted_length.hpp>
0017
0018 #include <boost/geometry/strategies/detail.hpp>
0019 #include <boost/geometry/strategies/centroid/services.hpp>
0020
0021 #include <boost/geometry/util/type_traits.hpp>
0022
0023
0024 namespace boost { namespace geometry
0025 {
0026
0027 namespace strategies { namespace centroid
0028 {
0029
0030 template <typename CalculationType = void>
0031 struct cartesian
0032     : public strategies::detail::cartesian_base
0033 {
0034     template <typename Geometry>
0035     static auto centroid(Geometry const&,
0036                          std::enable_if_t
0037                             <
0038                                 util::is_pointlike<Geometry>::value
0039                             > * = nullptr)
0040     {
0041         return strategy::centroid::average<>();
0042     }
0043
0044     template <typename Geometry>
0045     static auto centroid(Geometry const&,
0046                          std::enable_if_t
0047                             <
0048                                 util::is_polylinear<Geometry>::value
0049                             > * = nullptr)
0050     {
0051         return strategy::centroid::weighted_length<void, void, CalculationType>();
0052     }
0053
0054     template <typename Geometry>
0055     static auto centroid(Geometry const&,
0056                          std::enable_if_t
0057                             <
0058                                 util::is_polygonal<Geometry>::value
0059                              // TODO: This condition was used for the legacy default strategy
0060                              // && geometry::dimension<Geometry>::value == 2
0061                             > * = nullptr)
0062     {
0063         return strategy::centroid::bashein_detmer<void, void, CalculationType>();
0064     }
0065
0066     // TODO: Box and Segment should have proper strategies.
0067     template <typename Geometry, typename Point>
0068     static auto centroid(Geometry const&, Point const&,
0069                          std::enable_if_t
0070                             <
0071                                 util::is_segment<Geometry>::value
0072                              || util::is_box<Geometry>::value
0073                             > * = nullptr)
0074     {
0075         return strategy::centroid::not_applicable_strategy();
0076     }
0077 };
0078
0079
0080 namespace services
0081 {
0082
0083 template <typename Geometry>
0084 struct default_strategy<Geometry, cartesian_tag>
0085 {
0086     using type = strategies::centroid::cartesian<>;
0087 };
0088
0089
0090 template <typename PC, typename PG>
0091 struct strategy_converter<strategy::centroid::average<PC, PG> >
0092 {
0093     static auto get(strategy::centroid::average<PC, PG> const&)
0094     {
0095         return strategies::centroid::cartesian<>();
0096     }
0097 };
0098
0099 template <typename PC, typename PG>
0100 struct strategy_converter<strategy::centroid::weighted_length<PC, PG> >
0101 {
0102     static auto get(strategy::centroid::weighted_length<PC, PG> const&)
0103     {
0104         return strategies::centroid::cartesian<>();
0105     }
0106 };
0107
0108 template <typename PC, typename PG, typename CT>
0109 struct strategy_converter<strategy::centroid::bashein_detmer<PC, PG, CT> >
0110 {
0111     static auto get(strategy::centroid::bashein_detmer<PC, PG, CT> const&)
0112     {
0113         return strategies::centroid::cartesian<CT>();
0114     }
0115 };
0116
0117 } // namespace services
0118
0119 }} // namespace strategies::centroid
0120
0121 }} // namespace boost::geometry
0122
0123 #endif // BOOST_GEOMETRY_STRATEGIES_CENTROID_CARTESIAN_HPP