ceph/src/boost/libs/geometry/include/boost/geometry/algorithms/detail/overlay/convert_ring.hpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2
   3 // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
   4
   5 // Use, modification and distribution is subject to the Boost Software License,
   6 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   7 // http://www.boost.org/LICENSE_1_0.txt)
   8
   9 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_CONVERT_RING_HPP
  10 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_CONVERT_RING_HPP
  11
  12
  13 #include <boost/mpl/assert.hpp>
  14 #include <boost/range.hpp>
  15 #include <boost/range/algorithm/reverse.hpp>
  16
  17 #include <boost/geometry/core/tags.hpp>
  18 #include <boost/geometry/core/exterior_ring.hpp>
  19 #include <boost/geometry/core/interior_rings.hpp>
  20 #include <boost/geometry/algorithms/detail/ring_identifier.hpp>
  21
  22 #include <boost/geometry/algorithms/convert.hpp>
  23
  24
  25 namespace boost { namespace geometry
  26 {
  27
  28
  29 #ifndef DOXYGEN_NO_DETAIL
  30 namespace detail { namespace overlay
  31 {
  32
  33
  34 template<typename Tag>
  35 struct convert_ring
  36 {
  37     BOOST_MPL_ASSERT_MSG
  38         (
  39             false, NOT_OR_NOT_YET_IMPLEMENTED_FOR_THIS_GEOMETRY_TAG
  40             , (types<Tag>)
  41         );
  42 };
  43
  44 template<>
  45 struct convert_ring<ring_tag>
  46 {
  47     template<typename Destination, typename Source>
  48     static inline void apply(Destination& destination, Source const& source,
  49                 bool append, bool reverse)
  50     {
  51         if (! append)
  52         {
  53             geometry::convert(source, destination);
  54             if (reverse)
  55             {
  56                 boost::reverse(destination);
  57             }
  58         }
  59     }
  60 };
  61
  62
  63 template<>
  64 struct convert_ring<polygon_tag>
  65 {
  66     template<typename Destination, typename Source>
  67     static inline void apply(Destination& destination, Source const& source,
  68                 bool append, bool reverse)
  69     {
  70         if (! append)
  71         {
  72             geometry::convert(source, exterior_ring(destination));
  73             if (reverse)
  74             {
  75                 boost::reverse(exterior_ring(destination));
  76             }
  77         }
  78         else
  79         {
  80             // Avoid adding interior rings which are invalid
  81             // because of its number of points:
  82             std::size_t const min_num_points
  83                     = core_detail::closure::minimum_ring_size
  84                             <
  85                                 geometry::closure<Destination>::value
  86                             >::value;
  87
  88             if (geometry::num_points(source) >= min_num_points)
  89             {
  90                 interior_rings(destination).resize(
  91                             interior_rings(destination).size() + 1);
  92                 geometry::convert(source, interior_rings(destination).back());
  93                 if (reverse)
  94                 {
  95                     boost::reverse(interior_rings(destination).back());
  96                 }
  97             }
  98         }
  99     }
 100 };
 101
 102
 103 }} // namespace detail::overlay
 104 #endif // DOXYGEN_NO_DETAIL
 105
 106
 107 }} // namespace boost::geometry
 108
 109
 110 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_CONVERT_RING_HPP