ceph/src/boost/libs/geometry/include/boost/geometry/algorithms/detail/overlay/ring_properties.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_RING_PROPERTIES_HPP
  10 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_RING_PROPERTIES_HPP
  11
  12
  13 #include <boost/geometry/algorithms/area.hpp>
  14 #include <boost/geometry/algorithms/within.hpp>
  15 #include <boost/geometry/algorithms/detail/point_on_border.hpp>
  16
  17
  18 namespace boost { namespace geometry
  19 {
  20
  21
  22 #ifndef DOXYGEN_NO_DETAIL
  23 namespace detail { namespace overlay
  24 {
  25
  26 template <typename Point>
  27 struct ring_properties
  28 {
  29     typedef Point point_type;
  30     typedef typename default_area_result<Point>::type area_type;
  31
  32     bool valid;
  33
  34     // Filled by "select_rings"
  35     Point point;
  36     area_type area;
  37
  38     // Filled by "update_ring_selection"
  39     bool reversed;
  40
  41     // Filled/used by "assign_rings"
  42     bool discarded;
  43     ring_identifier parent;
  44     area_type parent_area;
  45     std::vector<ring_identifier> children;
  46
  47     inline ring_properties()
  48         : valid(false)
  49         , area(area_type())
  50         , reversed(false)
  51         , discarded(false)
  52         , parent_area(-1)
  53     {}
  54
  55     template <typename RingOrBox>
  56     inline ring_properties(RingOrBox const& ring_or_box)
  57         : reversed(false)
  58         , discarded(false)
  59         , parent_area(-1)
  60     {
  61         this->area = geometry::area(ring_or_box);
  62         // We should take a point somewhere in the middle of the ring,
  63         // to avoid taking a point on a (self)tangency,
  64         // in cases where multiple points come together
  65         valid = geometry::point_on_border(this->point, ring_or_box, true);
  66     }
  67
  68     inline area_type get_area() const
  69     {
  70         return reversed ? -area : area;
  71     }
  72 };
  73
  74 }} // namespace detail::overlay
  75 #endif // DOXYGEN_NO_DETAIL
  76
  77
  78 }} // namespace boost::geometry
  79
  80
  81 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_RING_PROPERTIES_HPP