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/mpl/assert.hpp>
  23 #include <boost/range.hpp>
  24
  25 #include <boost/geometry/core/access.hpp>
  26 #include <boost/geometry/core/assert.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),
  62                         static_cast<std::size_t>(section.ring_id.ring_index));
  63     }
  64 };
  65
  66
  67 template
  68 <
  69     typename MultiGeometry,
  70     typename Section,
  71     typename Policy
  72 >
  73 struct full_section_multi
  74 {
  75     static inline typename ring_return_type<MultiGeometry const>::type apply(
  76                 MultiGeometry const& multi, Section const& section)
  77     {
  78         typedef typename boost::range_size<MultiGeometry>::type size_type;
  79
  80         BOOST_GEOMETRY_ASSERT
  81             (
  82                 section.ring_id.multi_index >= 0
  83                 && size_type(section.ring_id.multi_index) < boost::size(multi)
  84             );
  85
  86         return Policy::apply(range::at(multi, size_type(section.ring_id.multi_index)), section);
  87     }
  88 };
  89
  90
  91 }} // namespace detail::section
  92 #endif
  93
  94
  95 #ifndef DOXYGEN_NO_DISPATCH
  96 namespace dispatch
  97 {
  98
  99
 100 template
 101 <
 102     typename Tag,
 103     typename Geometry,
 104     typename Section
 105 >
 106 struct range_by_section
 107 {
 108     BOOST_MPL_ASSERT_MSG
 109         (
 110             false, NOT_OR_NOT_YET_IMPLEMENTED_FOR_THIS_GEOMETRY_TYPE
 111             , (types<Geometry>)
 112         );
 113 };
 114
 115
 116 template <typename LineString, typename Section>
 117 struct range_by_section<linestring_tag, LineString, Section>
 118     : detail::section::full_section_range<LineString, Section>
 119 {};
 120
 121
 122 template <typename Ring, typename Section>
 123 struct range_by_section<ring_tag, Ring, Section>
 124     : detail::section::full_section_range<Ring, Section>
 125 {};
 126
 127
 128 template <typename Polygon, typename Section>
 129 struct range_by_section<polygon_tag, Polygon, Section>
 130     : detail::section::full_section_polygon<Polygon, Section>
 131 {};
 132
 133
 134 template <typename MultiPolygon, typename Section>
 135 struct range_by_section<multi_polygon_tag, MultiPolygon, Section>
 136     : detail::section::full_section_multi
 137         <
 138             MultiPolygon,
 139             Section,
 140             detail::section::full_section_polygon
 141                 <
 142                     typename boost::range_value<MultiPolygon>::type,
 143                     Section
 144                 >
 145        >
 146 {};
 147
 148 template <typename MultiLinestring, typename Section>
 149 struct range_by_section<multi_linestring_tag, MultiLinestring, Section>
 150     : detail::section::full_section_multi
 151         <
 152             MultiLinestring,
 153             Section,
 154             detail::section::full_section_range
 155                 <
 156                     typename boost::range_value<MultiLinestring>::type,
 157                     Section
 158                 >
 159        >
 160 {};
 161
 162
 163 } // namespace dispatch
 164 #endif
 165
 166
 167 /*!
 168     \brief Get full ring (exterior, one of interiors, one from multi)
 169         indicated by the specified section
 170     \ingroup sectionalize
 171     \tparam Geometry type
 172     \tparam Section type of section to get from
 173     \param geometry geometry to take section of
 174     \param section structure with section
 175  */
 176 template <typename Geometry, typename Section>
 177 inline typename ring_return_type<Geometry const>::type
 178             range_by_section(Geometry const& geometry, Section const& section)
 179 {
 180     concepts::check<Geometry const>();
 181
 182     return dispatch::range_by_section
 183         <
 184             typename tag<Geometry>::type,
 185             Geometry,
 186             Section
 187         >::apply(geometry, section);
 188 }
 189
 190
 191 }} // namespace boost::geometry
 192
 193 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_SECTIONS_RANGE_BY_SECTION_HPP