1 // Boost.Geometry (aka GGL, Generic Geometry Library)
3 // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
4 // Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
5 // Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
6 // Copyright (c) 2014 Adam Wulkiewicz, Lodz, Poland.
8 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
9 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
11 // Use, modification and distribution is subject to the Boost Software License,
12 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
13 // http://www.boost.org/LICENSE_1_0.txt)
15 #ifndef BOOST_GEOMETRY_ALGORITHMS_REVERSE_HPP
16 #define BOOST_GEOMETRY_ALGORITHMS_REVERSE_HPP
20 #include <boost/range.hpp>
21 #include <boost/type_traits/remove_reference.hpp>
23 #include <boost/variant/apply_visitor.hpp>
24 #include <boost/variant/static_visitor.hpp>
25 #include <boost/variant/variant_fwd.hpp>
27 #include <boost/geometry/algorithms/detail/interior_iterator.hpp>
28 #include <boost/geometry/algorithms/detail/multi_modify.hpp>
29 #include <boost/geometry/core/interior_rings.hpp>
30 #include <boost/geometry/core/tags.hpp>
31 #include <boost/geometry/geometries/concepts/check.hpp>
34 namespace boost { namespace geometry
38 #ifndef DOXYGEN_NO_DETAIL
39 namespace detail { namespace reverse
45 template <typename Range>
46 static inline void apply(Range& range)
48 std::reverse(boost::begin(range), boost::end(range));
53 struct polygon_reverse: private range_reverse
55 template <typename Polygon>
56 static inline void apply(Polygon& polygon)
58 range_reverse::apply(exterior_ring(polygon));
60 typename interior_return_type<Polygon>::type
61 rings = interior_rings(polygon);
63 for (typename detail::interior_iterator<Polygon>::type
64 it = boost::begin(rings); it != boost::end(rings); ++it)
66 range_reverse::apply(*it);
72 }} // namespace detail::reverse
73 #endif // DOXYGEN_NO_DETAIL
76 #ifndef DOXYGEN_NO_DISPATCH
81 template <typename Geometry, typename Tag = typename tag<Geometry>::type>
84 static inline void apply(Geometry&)
89 template <typename Ring>
90 struct reverse<Ring, ring_tag>
91 : detail::reverse::range_reverse
95 template <typename LineString>
96 struct reverse<LineString, linestring_tag>
97 : detail::reverse::range_reverse
101 template <typename Polygon>
102 struct reverse<Polygon, polygon_tag>
103 : detail::reverse::polygon_reverse
107 template <typename Geometry>
108 struct reverse<Geometry, multi_linestring_tag>
109 : detail::multi_modify
112 detail::reverse::range_reverse
117 template <typename Geometry>
118 struct reverse<Geometry, multi_polygon_tag>
119 : detail::multi_modify
122 detail::reverse::polygon_reverse
128 } // namespace dispatch
132 namespace resolve_variant
135 template <typename Geometry>
138 static void apply(Geometry& geometry)
140 concepts::check<Geometry>();
141 dispatch::reverse<Geometry>::apply(geometry);
145 template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
146 struct reverse<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
148 struct visitor: boost::static_visitor<void>
150 template <typename Geometry>
151 void operator()(Geometry& geometry) const
153 reverse<Geometry>::apply(geometry);
157 static inline void apply(boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>& geometry)
159 boost::apply_visitor(visitor(), geometry);
163 } // namespace resolve_variant
167 \brief Reverses the points within a geometry
168 \details Generic function to reverse a geometry. It resembles the std::reverse
169 functionality, but it takes the geometry type into account. Only for a ring
170 or for a linestring it is the same as the std::reverse.
172 \tparam Geometry \tparam_geometry
173 \param geometry \param_geometry which will be reversed
175 \qbk{[include reference/algorithms/reverse.qbk]}
177 template <typename Geometry>
178 inline void reverse(Geometry& geometry)
180 resolve_variant::reverse<Geometry>::apply(geometry);
183 }} // namespace boost::geometry
186 #endif // BOOST_GEOMETRY_ALGORITHMS_REVERSE_HPP