boost/geometry/algorithms/detail/sections/range_by_section.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 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
   8 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
   9
  10 // This file was modified by Oracle on 2013, 2014.
  11 // Modifications copyright (c) 2013, 2014, Oracle and/or its affiliates.
  12
  13 // Use, modification and distribution is subject to the Boost Software License,
  14 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  15 // http://www.boost.org/LICENSE_1_0.txt)
  16
  17 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
  18
  19 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_SECTIONS_RANGE_BY_SECTION_HPP
  20 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_SECTIONS_RANGE_BY_SECTION_HPP
  21
  22 #include <boost/assert.hpp>
  23 #include <boost/mpl/assert.hpp>
  24 #include <boost/range.hpp>
  25
  26 #include <boost/geometry/core/access.hpp>
  27 #include <boost/geometry/core/closure.hpp>
  28 #include <boost/geometry/core/exterior_ring.hpp>
  29 #include <boost/geometry/core/interior_rings.hpp>
  30 #include <boost/geometry/core/ring_type.hpp>
  31 #include <boost/geometry/core/tags.hpp>
  32 #include <boost/geometry/geometries/concepts/check.hpp>
  33 #include <boost/geometry/util/range.hpp>
  34
  35
  36 namespace boost { namespace geometry
  37 {
  38
  39 #ifndef DOXYGEN_NO_DETAIL
  40 namespace detail { namespace section
  41 {
  42
  43
  44 template <typename Range, typename Section>
  45 struct full_section_range
  46 {
  47     static inline Range const& apply(Range const& range, Section const& )
  48     {
  49         return range;
  50     }
  51 };
  52
  53
  54 template <typename Polygon, typename Section>
  55 struct full_section_polygon
  56 {
  57     static inline typename ring_return_type<Polygon const>::type apply(Polygon const& polygon, Section const& section)
  58     {
  59         return section.ring_id.ring_index < 0
  60             ? geometry::exterior_ring(polygon)
  61             : range::at(geometry::interior_rings(polygon), section.ring_id.ring_index);
  62     }
  63 };
  64
  65
  66 template
  67 <
  68     typename MultiGeometry,
  69     typename Section,
  70     typename Policy
  71 >
  72 struct full_section_multi
  73 {
  74     static inline typename ring_return_type<MultiGeometry const>::type apply(
  75                 MultiGeometry const& multi, Section const& section)
  76     {
  77         BOOST_ASSERT
  78             (
  79                 section.ring_id.multi_index >= 0
  80                 && section.ring_id.multi_index < int(boost::size(multi))
  81             );
  82
  83         return Policy::apply(range::at(multi, section.ring_id.multi_index), section);
  84     }
  85 };
  86
  87
  88 }} // namespace detail::section
  89 #endif
  90
  91
  92 #ifndef DOXYGEN_NO_DISPATCH
  93 namespace dispatch
  94 {
  95
  96
  97 template
  98 <
  99     typename Tag,
 100     typename Geometry,
 101     typename Section
 102 >
 103 struct range_by_section
 104 {
 105     BOOST_MPL_ASSERT_MSG
 106         (
 107             false, NOT_OR_NOT_YET_IMPLEMENTED_FOR_THIS_GEOMETRY_TYPE
 108             , (types<Geometry>)
 109         );
 110 };
 111
 112
 113 template <typename LineString, typename Section>
 114 struct range_by_section<linestring_tag, LineString, Section>
 115     : detail::section::full_section_range<LineString, Section>
 116 {};
 117
 118
 119 template <typename Ring, typename Section>
 120 struct range_by_section<ring_tag, Ring, Section>
 121     : detail::section::full_section_range<Ring, Section>
 122 {};
 123
 124
 125 template <typename Polygon, typename Section>
 126 struct range_by_section<polygon_tag, Polygon, Section>
 127     : detail::section::full_section_polygon<Polygon, Section>
 128 {};
 129
 130
 131 template <typename MultiPolygon, typename Section>
 132 struct range_by_section<multi_polygon_tag, MultiPolygon, Section>
 133     : detail::section::full_section_multi
 134         <
 135             MultiPolygon,
 136             Section,
 137             detail::section::full_section_polygon
 138                 <
 139                     typename boost::range_value<MultiPolygon>::type,
 140                     Section
 141                 >
 142        >
 143 {};
 144
 145 template <typename MultiLinestring, typename Section>
 146 struct range_by_section<multi_linestring_tag, MultiLinestring, Section>
 147     : detail::section::full_section_multi
 148         <
 149             MultiLinestring,
 150             Section,
 151             detail::section::full_section_range
 152                 <
 153                     typename boost::range_value<MultiLinestring>::type,
 154                     Section
 155                 >
 156        >
 157 {};
 158
 159
 160 } // namespace dispatch
 161 #endif
 162
 163
 164 /*!
 165     \brief Get full ring (exterior, one of interiors, one from multi)
 166         indicated by the specified section
 167     \ingroup sectionalize
 168     \tparam Geometry type
 169     \tparam Section type of section to get from
 170     \param geometry geometry to take section of
 171     \param section structure with section
 172  */
 173 template <typename Geometry, typename Section>
 174 inline typename ring_return_type<Geometry const>::type
 175             range_by_section(Geometry const& geometry, Section const& section)
 176 {
 177     concept::check<Geometry const>();
 178
 179     return dispatch::range_by_section
 180         <
 181             typename tag<Geometry>::type,
 182             Geometry,
 183             Section
 184         >::apply(geometry, section);
 185 }
 186
 187
 188 }} // namespace boost::geometry
 189
 190 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_SECTIONS_RANGE_BY_SECTION_HPP