ceph/src/boost/boost/geometry/algorithms/detail/point_on_border.hpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2
   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
   7 // This file was modified by Oracle on 2017, 2018.
   8 // Modifications copyright (c) 2017-2018 Oracle and/or its affiliates.
   9 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
  10
  11 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
  12 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
  13
  14 // Use, modification and distribution is subject to the Boost Software License,
  15 // Version 1.Dimension. (See accompanying file LICENSE_1_0.txt or copy at
  16 // http://www.boost.org/LICENSE_1_0.txt)
  17
  18 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_POINT_ON_BORDER_HPP
  19 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_POINT_ON_BORDER_HPP
  20
  21
  22 #include <cstddef>
  23
  24 #include <boost/range.hpp>
  25 #include <boost/static_assert.hpp>
  26
  27 #include <boost/geometry/core/tags.hpp>
  28 #include <boost/geometry/core/point_type.hpp>
  29 #include <boost/geometry/core/ring_type.hpp>
  30
  31 #include <boost/geometry/geometries/concepts/check.hpp>
  32
  33 #include <boost/geometry/algorithms/assign.hpp>
  34 #include <boost/geometry/algorithms/detail/convert_point_to_point.hpp>
  35 #include <boost/geometry/algorithms/detail/equals/point_point.hpp>
  36
  37 #include <boost/geometry/util/condition.hpp>
  38
  39
  40 namespace boost { namespace geometry
  41 {
  42
  43
  44 #ifndef DOXYGEN_NO_DETAIL
  45 namespace detail { namespace point_on_border
  46 {
  47
  48
  49 struct get_point
  50 {
  51     template <typename Point>
  52     static inline bool apply(Point& destination, Point const& source)
  53     {
  54         destination = source;
  55         return true;
  56     }
  57 };
  58
  59
  60 struct point_on_range
  61 {
  62     // Version with iterator
  63     template<typename Point, typename Iterator>
  64     static inline bool apply(Point& point, Iterator begin, Iterator end)
  65     {
  66         if (begin == end)
  67         {
  68             return false;
  69         }
  70
  71         geometry::detail::conversion::convert_point_to_point(*begin, point);
  72         return true;
  73     }
  74
  75     // Version with range
  76     template<typename Point, typename Range>
  77     static inline bool apply(Point& point, Range const& range)
  78     {
  79         return apply(point, boost::begin(range), boost::end(range));
  80     }
  81 };
  82
  83
  84 struct point_on_polygon
  85 {
  86     template<typename Point, typename Polygon>
  87     static inline bool apply(Point& point, Polygon const& polygon)
  88     {
  89         return point_on_range::apply(point, exterior_ring(polygon));
  90     }
  91 };
  92
  93
  94 struct point_on_box
  95 {
  96     template<typename Point, typename Box>
  97     static inline bool apply(Point& point, Box const& box)
  98     {
  99         detail::assign::assign_box_2d_corner<min_corner, min_corner>(box, point);
 100         return true;
 101     }
 102 };
 103
 104
 105 template <typename Policy>
 106 struct point_on_multi
 107 {
 108     template<typename Point, typename MultiGeometry>
 109     static inline bool apply(Point& point, MultiGeometry const& multi)
 110     {
 111         // Take a point on the first multi-geometry
 112         // (i.e. the first that is not empty)
 113         for (typename boost::range_iterator
 114                 <
 115                     MultiGeometry const
 116                 >::type it = boost::begin(multi);
 117             it != boost::end(multi);
 118             ++it)
 119         {
 120             if (Policy::apply(point, *it))
 121             {
 122                 return true;
 123             }
 124         }
 125         return false;
 126     }
 127 };
 128
 129
 130 }} // namespace detail::point_on_border
 131 #endif // DOXYGEN_NO_DETAIL
 132
 133
 134 #ifndef DOXYGEN_NO_DISPATCH
 135 namespace dispatch
 136 {
 137
 138
 139 template <typename GeometryTag>
 140 struct point_on_border
 141 {};
 142
 143 template <>
 144 struct point_on_border<point_tag>
 145     : detail::point_on_border::get_point
 146 {};
 147
 148 template <>
 149 struct point_on_border<linestring_tag>
 150     : detail::point_on_border::point_on_range
 151 {};
 152
 153 template <>
 154 struct point_on_border<ring_tag>
 155     : detail::point_on_border::point_on_range
 156 {};
 157
 158 template <>
 159 struct point_on_border<polygon_tag>
 160     : detail::point_on_border::point_on_polygon
 161 {};
 162
 163 template <>
 164 struct point_on_border<box_tag>
 165     : detail::point_on_border::point_on_box
 166 {};
 167
 168
 169 template <>
 170 struct point_on_border<multi_polygon_tag>
 171     : detail::point_on_border::point_on_multi
 172         <
 173             detail::point_on_border::point_on_polygon
 174         >
 175 {};
 176
 177
 178 template <>
 179 struct point_on_border<multi_linestring_tag>
 180     : detail::point_on_border::point_on_multi
 181         <
 182             detail::point_on_border::point_on_range
 183         >
 184 {};
 185
 186
 187 } // namespace dispatch
 188 #endif // DOXYGEN_NO_DISPATCH
 189
 190
 191 /*!
 192 \brief Take point on a border
 193 \ingroup overlay
 194 \tparam Geometry geometry type. This also defines the type of the output point
 195 \param point to assign
 196 \param geometry geometry to take point from
 197 \return TRUE if successful, else false.
 198     It is only false if polygon/line have no points
 199 \note for a polygon, it is always a point on the exterior ring
 200  */
 201 template <typename Point, typename Geometry>
 202 inline bool point_on_border(Point& point, Geometry const& geometry)
 203 {
 204     concepts::check<Point>();
 205     concepts::check<Geometry const>();
 206
 207     return dispatch::point_on_border
 208             <
 209                 typename tag<Geometry>::type
 210             >::apply(point, geometry);
 211 }
 212
 213
 214 }} // namespace boost::geometry
 215
 216
 217 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_POINT_ON_BORDER_HPP