boost/geometry/algorithms/detail/has_self_intersections.hpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2
   3 // Copyright (c) 2011-2012 Barend Gehrels, Amsterdam, the Netherlands.
   4 // Copyright (c) 2017 Adam Wulkiewicz, Lodz, Poland.
   5
   6 // This file was modified by Oracle on 2017.
   7 // Modifications copyright (c) 2017 Oracle and/or its affiliates.
   8 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
   9
  10 // Use, modification and distribution is subject to the Boost Software License,
  11 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  12 // http://www.boost.org/LICENSE_1_0.txt)
  13
  14 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_HAS_SELF_INTERSECTIONS_HPP
  15 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_HAS_SELF_INTERSECTIONS_HPP
  16
  17 #include <deque>
  18
  19 #include <boost/range.hpp>
  20 #include <boost/throw_exception.hpp>
  21
  22 #include <boost/geometry/core/point_type.hpp>
  23 #include <boost/geometry/algorithms/detail/overlay/turn_info.hpp>
  24 #include <boost/geometry/algorithms/detail/overlay/get_turns.hpp>
  25 #include <boost/geometry/algorithms/detail/overlay/self_turn_points.hpp>
  26
  27 #include <boost/geometry/policies/disjoint_interrupt_policy.hpp>
  28 #include <boost/geometry/policies/robustness/robust_point_type.hpp>
  29 #include <boost/geometry/policies/robustness/segment_ratio_type.hpp>
  30 #include <boost/geometry/policies/robustness/get_rescale_policy.hpp>
  31
  32 #ifdef BOOST_GEOMETRY_DEBUG_HAS_SELF_INTERSECTIONS
  33 #  include <boost/geometry/algorithms/detail/overlay/debug_turn_info.hpp>
  34 #  include <boost/geometry/io/dsv/write.hpp>
  35 #endif
  36
  37
  38 namespace boost { namespace geometry
  39 {
  40
  41
  42 #if ! defined(BOOST_GEOMETRY_OVERLAY_NO_THROW)
  43
  44 /*!
  45 \brief Overlay Invalid Input Exception
  46 \ingroup overlay
  47 \details The overlay_invalid_input_exception is thrown at invalid input
  48  */
  49 class overlay_invalid_input_exception : public geometry::exception
  50 {
  51 public:
  52
  53     inline overlay_invalid_input_exception() {}
  54
  55     virtual char const* what() const throw()
  56     {
  57         return "Boost.Geometry Overlay invalid input exception";
  58     }
  59 };
  60
  61 #endif
  62
  63
  64 #ifndef DOXYGEN_NO_DETAIL
  65 namespace detail { namespace overlay
  66 {
  67
  68
  69 template <typename Geometry, typename Strategy, typename RobustPolicy>
  70 inline bool has_self_intersections(Geometry const& geometry,
  71         Strategy const& strategy,
  72         RobustPolicy const& robust_policy,
  73         bool throw_on_self_intersection = true)
  74 {
  75     typedef typename point_type<Geometry>::type point_type;
  76     typedef turn_info
  77     <
  78         point_type,
  79         typename segment_ratio_type<point_type, RobustPolicy>::type
  80     > turn_info;
  81     std::deque<turn_info> turns;
  82     detail::disjoint::disjoint_interrupt_policy policy;
  83
  84     geometry::self_turns<detail::overlay::assign_null_policy>(geometry, strategy, robust_policy, turns, policy);
  85
  86 #ifdef BOOST_GEOMETRY_DEBUG_HAS_SELF_INTERSECTIONS
  87     bool first = true;
  88 #endif
  89     for(typename std::deque<turn_info>::const_iterator it = boost::begin(turns);
  90         it != boost::end(turns); ++it)
  91     {
  92         turn_info const& info = *it;
  93         bool const both_union_turn =
  94             info.operations[0].operation == detail::overlay::operation_union
  95             && info.operations[1].operation == detail::overlay::operation_union;
  96         bool const both_intersection_turn =
  97             info.operations[0].operation == detail::overlay::operation_intersection
  98             && info.operations[1].operation == detail::overlay::operation_intersection;
  99
 100         bool const valid = (both_union_turn || both_intersection_turn)
 101             && (info.method == detail::overlay::method_touch
 102                 || info.method == detail::overlay::method_touch_interior);
 103
 104         if (! valid)
 105         {
 106 #ifdef BOOST_GEOMETRY_DEBUG_HAS_SELF_INTERSECTIONS
 107             if (first)
 108             {
 109                 std::cout << "turn points: " << std::endl;
 110                 first = false;
 111             }
 112             std::cout << method_char(info.method);
 113             for (int i = 0; i < 2; i++)
 114             {
 115                 std::cout << " " << operation_char(info.operations[i].operation);
 116                 std::cout << " " << info.operations[i].seg_id;
 117             }
 118             std::cout << " " << geometry::dsv(info.point) << std::endl;
 119 #endif
 120
 121 #if ! defined(BOOST_GEOMETRY_OVERLAY_NO_THROW)
 122             if (throw_on_self_intersection)
 123             {
 124                 BOOST_THROW_EXCEPTION(overlay_invalid_input_exception());
 125             }
 126 #endif
 127             return true;
 128         }
 129
 130     }
 131     return false;
 132 }
 133
 134 // For backward compatibility
 135 template <typename Geometry>
 136 inline bool has_self_intersections(Geometry const& geometry,
 137                     bool throw_on_self_intersection = true)
 138 {
 139     typedef typename geometry::point_type<Geometry>::type point_type;
 140     typedef typename geometry::rescale_policy_type<point_type>::type
 141         rescale_policy_type;
 142
 143     typename strategy::intersection::services::default_strategy
 144         <
 145             typename cs_tag<Geometry>::type
 146         >::type strategy;
 147
 148     rescale_policy_type robust_policy
 149             = geometry::get_rescale_policy<rescale_policy_type>(geometry);
 150
 151     return has_self_intersections(geometry, strategy, robust_policy,
 152                                   throw_on_self_intersection);
 153 }
 154
 155
 156 }} // namespace detail::overlay
 157 #endif // DOXYGEN_NO_DETAIL
 158
 159
 160 }} // namespace boost::geometry
 161
 162
 163 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_HAS_SELF_INTERSECTIONS_HPP
 164