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 // Boost.Geometry (aka GGL, Generic Geometry Library)
 
 // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
 // Copyright (c) 2013-2017 Adam Wulkiewicz, Lodz, Poland.
 
 // This file was modified by Oracle on 2013-2024.
 // Modifications copyright (c) 2013-2024 Oracle and/or its affiliates.
 // Contributed and/or modified by Vissarion Fysikopoulos, on behalf of Oracle
 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
 
 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
 
 // Use, modification and distribution is subject to the Boost Software License,
 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #ifndef BOOST_GEOMETRY_STRATEGY_SPHERICAL_POINT_IN_POLY_WINDING_HPP
 #define BOOST_GEOMETRY_STRATEGY_SPHERICAL_POINT_IN_POLY_WINDING_HPP
 
 
 #include <boost/geometry/core/access.hpp>
 #include <boost/geometry/core/coordinate_system.hpp>
 #include <boost/geometry/core/cs.hpp>
 #include <boost/geometry/core/tags.hpp>
 
 #include <boost/geometry/util/math.hpp>
 #include <boost/geometry/util/select_calculation_type.hpp>
 #include <boost/geometry/util/normalize_spheroidal_coordinates.hpp>
 
 #include <boost/geometry/strategy/spherical/expand_point.hpp>
 
 #include <boost/geometry/strategies/cartesian/point_in_box.hpp>
 #include <boost/geometry/strategies/covered_by.hpp>
 #include <boost/geometry/strategies/side.hpp>
 #include <boost/geometry/strategies/spherical/disjoint_box_box.hpp>
 #include <boost/geometry/strategies/spherical/ssf.hpp>
 #include <boost/geometry/strategies/within.hpp>
 
 
 namespace boost { namespace geometry
 {
 
 namespace strategy { namespace within
 {
 
 
 #ifndef DOXYGEN_NO_DETAIL
 namespace detail
 {
 
 template <typename SideStrategy, typename CalculationType>
 class spherical_winding_base
 {
     template <typename Point, typename PointOfSegment>
     struct calculation_type
         : select_calculation_type
             <
                 Point,
                 PointOfSegment,
                 CalculationType
             >
     {};
 
     /*! subclass to keep state */
     class counter
     {
         int m_count;
         //int m_count_n;
         int m_count_s;
         int m_raw_count;
         int m_raw_count_anti;
         bool m_touches;
 
         inline int code() const
         {
             if (m_touches)
             {
                 return 0;
             }
 
             if (m_raw_count != 0 && m_raw_count_anti != 0)
             {
                 if (m_raw_count > 0) // right, wrap around south pole
                 {
                     return (m_count + m_count_s) == 0 ? -1 : 1;
                 }
                 else // left, wrap around north pole
                 {
                     //return (m_count + m_count_n) == 0 ? -1 : 1;
                     // m_count_n is 0
                     return m_count == 0 ? -1 : 1;
                 }
             }
 
             return m_count == 0 ? -1 : 1;
         }
 
     public :
         friend class spherical_winding_base;
 
         inline counter()
             : m_count(0)
             //, m_count_n(0)
             , m_count_s(0)
             , m_raw_count(0)
             , m_raw_count_anti(0)
             , m_touches(false)
         {}
 
     };
 
     struct count_info
     {
         explicit count_info(int c = 0, bool ia = false)
             : count(c)
             , is_anti(ia)
         {}
 
         int count;
         bool is_anti;
     };
 
 public:
     using cs_tag = typename SideStrategy::cs_tag;
 
     spherical_winding_base() = default;
 
     template <typename Model>
     explicit spherical_winding_base(Model const& model)
         : m_side_strategy(model)
     {}
 
     // Typedefs and static methods to fulfill the concept
     typedef counter state_type;
 
     template <typename Point, typename PointOfSegment>
     inline bool apply(Point const& point,
                       PointOfSegment const& s1, PointOfSegment const& s2,
                       counter& state) const
     {
         typedef typename calculation_type<Point, PointOfSegment>::type calc_t;
         typedef typename geometry::detail::cs_angular_units<Point>::type units_t;
         typedef math::detail::constants_on_spheroid<calc_t, units_t> constants;
 
         bool eq1 = false;
         bool eq2 = false;
         bool s_antipodal = false;
 
         count_info ci = check_segment(point, s1, s2, state, eq1, eq2, s_antipodal);
         if (ci.count != 0)
         {
             if (! ci.is_anti)
             {
                 int side = 0;
                 if (ci.count == 1 || ci.count == -1)
                 {
                     side = side_equal(point, eq1 ? s1 : s2, ci);
                 }
                 else // count == 2 || count == -2
                 {
                     if (! s_antipodal)
                     {
                         // 1 left, -1 right
                         side = m_side_strategy.apply(s1, s2, point);
                     }
                     else
                     {
                         calc_t const pi = constants::half_period();
                         calc_t const s1_lat = get<1>(s1);
                         calc_t const s2_lat = get<1>(s2);
 
                         side = math::sign(ci.count)
                              * (pi - s1_lat - s2_lat <= pi // segment goes through north pole
                                 ? -1 // going right all points will be on right side
                                 : 1); // going right all points will be on left side
                     }
                 }
 
                 if (side == 0)
                 {
                     // Point is lying on segment
                     state.m_touches = true;
                     state.m_count = 0;
                     return false;
                 }
 
                 // Side is NEG for right, POS for left.
                 // The count is -2 for left, 2 for right (or -1/1)
                 // Side positive thus means RIGHT and LEFTSIDE or LEFT and RIGHTSIDE
                 // See accompagnying figure (TODO)
                 if (side * ci.count > 0)
                 {
                     state.m_count += ci.count;
                 }
 
                 state.m_raw_count += ci.count;
             }
             else
             {
                 // Count negated because the segment is on the other side of the globe
                 // so it is reversed to match this side of the globe
 
                 // Assuming geometry wraps around north pole, for segments on the other side of the globe
                 // the point will always be RIGHT+RIGHTSIDE or LEFT+LEFTSIDE, so side*-count always < 0
                 //state.m_count_n -= 0;
 
                 // Assuming geometry wraps around south pole, for segments on the other side of the globe
                 // the point will always be RIGHT+LEFTSIDE or LEFT+RIGHTSIDE, so side*-count always > 0
                 state.m_count_s -= ci.count;
 
                 state.m_raw_count_anti -= ci.count;
             }
         }
         return ! state.m_touches;
     }
 
     static inline int result(counter const& state)
     {
         return state.code();
     }
 
 protected:
     template <typename Point, typename PointOfSegment>
     static inline count_info check_segment(Point const& point,
                                     PointOfSegment const& seg1,
                                     PointOfSegment const& seg2,
                                     counter& state,
                                     bool& eq1, bool& eq2, bool& s_antipodal)
     {
         if (check_touch(point, seg1, seg2, state, eq1, eq2, s_antipodal))
         {
             return count_info(0, false);
         }
 
         return calculate_count(point, seg1, seg2, eq1, eq2, s_antipodal);
     }
 
     template <typename Point, typename PointOfSegment>
     static inline int check_touch(Point const& point,
                                   PointOfSegment const& seg1,
                                   PointOfSegment const& seg2,
                                   counter& state,
                                   bool& eq1,
                                   bool& eq2,
                                   bool& s_antipodal)
     {
         typedef typename calculation_type<Point, PointOfSegment>::type calc_t;
         typedef typename geometry::detail::cs_angular_units<Point>::type units_t;
         typedef math::detail::constants_on_spheroid<calc_t, units_t> constants;
 
         calc_t const c0 = 0;
         calc_t const c2 = 2;
         calc_t const pi = constants::half_period();
         calc_t const half_pi = pi / c2;
 
         calc_t const p_lon = get<0>(point);
         calc_t const s1_lon = get<0>(seg1);
         calc_t const s2_lon = get<0>(seg2);
         calc_t const p_lat = get<1>(point);
         calc_t const s1_lat = get<1>(seg1);
         calc_t const s2_lat = get<1>(seg2);
 
         // NOTE: lat in {-90, 90} and arbitrary lon
         //  it doesn't matter what lon it is if it's a pole
         //  so e.g. if one of the segment endpoints is a pole
         //  then only the other lon matters
 
         bool eq1_strict = longitudes_equal<units_t>(s1_lon, p_lon);
         bool eq2_strict = longitudes_equal<units_t>(s2_lon, p_lon);
         bool eq1_anti = false;
         bool eq2_anti = false;
 
         calc_t const anti_p_lon = p_lon + (p_lon <= c0 ? pi : -pi);
 
         eq1 = eq1_strict // lon strictly equal to s1
             || (eq1_anti = longitudes_equal<units_t>(s1_lon, anti_p_lon)); // anti-lon strictly equal to s1
         eq2 = eq2_strict // lon strictly equal to s2
             || (eq2_anti = longitudes_equal<units_t>(s2_lon, anti_p_lon)); // anti-lon strictly equal to s2
 
         // segment overlapping pole
         calc_t const s_lon_diff = math::longitude_distance_signed<units_t>(s1_lon, s2_lon);
         s_antipodal = math::equals(s_lon_diff, pi);
         if (s_antipodal)
         {
             eq1 = eq2 = eq1 || eq2;
 
             // segment overlapping pole and point is pole
             if (math::equals(math::abs(p_lat), half_pi))
             {
                 eq1 = eq2 = true;
             }
         }
 
         // check whether point is on a segment with a pole endpoint
         if (math::longitude_distance_signed<units_t>(s2_lon, p_lon) == c0)
         {
             bool const s1_north = math::equals(get<1>(seg1), half_pi);
             bool const s1_south = math::equals(get<1>(seg1), -half_pi);
             if (s1_north || s1_south)
             {
                 state.m_touches = s1_south ? s2_lat > p_lat : s2_lat < p_lat;
                 return state.m_touches;
             }
         }
         if (math::longitude_distance_signed<units_t>(s1_lon, p_lon) == c0)
         {
             bool const s2_north = math::equals(get<1>(seg2), half_pi);
             bool const s2_south = math::equals(get<1>(seg2), -half_pi);
             if (s2_north || s2_south)
             {
                 state.m_touches = s2_south ? s1_lat > p_lat : s1_lat < p_lat;
                 return state.m_touches;
             }
         }
 
         // Both equal p -> segment vertical
         // The only thing which has to be done is check if point is ON segment
         if (eq1 && eq2)
         {
             // segment endpoints on the same sides of the globe
             if (! s_antipodal)
             {
                 // p's lat between segment endpoints' lats
                 if ( (s1_lat <= p_lat && s2_lat >= p_lat) || (s2_lat <= p_lat && s1_lat >= p_lat) )
                 {
                     if (!eq1_anti || !eq2_anti)
                     {
                         state.m_touches = true;
                     }
                 }
             }
             else
             {
                 // going through north or south pole?
                 if (pi - s1_lat - s2_lat <= pi)
                 {
                     if ( (eq1_strict && s1_lat <= p_lat) || (eq2_strict && s2_lat <= p_lat) // north
                             || math::equals(p_lat, half_pi) ) // point on north pole
                     {
                         state.m_touches = true;
                     }
                     else if (! eq1_strict && ! eq2_strict && math::equals(p_lat, -half_pi) ) // point on south pole
                     {
                         return false;
                     }
                 }
                 else // south pole
                 {
                     if ( (eq1_strict && s1_lat >= p_lat) || (eq2_strict && s2_lat >= p_lat) // south
                             || math::equals(p_lat, -half_pi) ) // point on south pole
                     {
                         state.m_touches = true;
                     }
                     else if (! eq1_strict && ! eq2_strict && math::equals(p_lat, half_pi) ) // point on north pole
                     {
                         return false;
                     }
                 }
             }
 
             return true;
         }
 
         return false;
     }
 
     // Called if point is not aligned with a vertical segment
     template <typename Point, typename PointOfSegment>
     static inline count_info calculate_count(Point const& point,
                                              PointOfSegment const& seg1,
                                              PointOfSegment const& seg2,
                                              bool eq1, bool eq2, bool s_antipodal)
     {
         typedef typename calculation_type<Point, PointOfSegment>::type calc_t;
         typedef typename geometry::detail::cs_angular_units<Point>::type units_t;
         typedef math::detail::constants_on_spheroid<calc_t, units_t> constants;
 
         // If both segment endpoints were poles below checks wouldn't be enough
         // but this means that either both are the same or that they are N/S poles
         // and therefore the segment is not valid.
         // If needed (eq1 && eq2 ? 0) could be returned
 
         calc_t const c0 = 0;
         calc_t const c2 = 2;
         calc_t const pi = constants::half_period();
         calc_t const half_pi = pi / c2;
 
         bool const s1_is_pole = math::equals(std::abs(get<1>(seg1)), half_pi);
         bool const s2_is_pole = math::equals(std::abs(get<1>(seg2)), half_pi);
 
         if (s1_is_pole && s2_is_pole)
         {
             return count_info(0, false);
         }
 
         calc_t const p = get<0>(point);
         calc_t s1 = get<0>(seg1);
         calc_t s2 = get<0>(seg2);
 
         // In case of a segment that contains a pole endpoint we need an arbitrary but consistent
         // longitude for that endpoint different than p's longitude
         if (s1_is_pole) s1 = (p != 0) ? 0 : 1;
         if (s2_is_pole) s2 = (p != 0) ? 0 : 1;
 
         calc_t const s1_p = math::longitude_distance_signed<units_t>(s1, p);
 
         if (s_antipodal)
         {
             return count_info(s1_p < c0 ? -2 : 2, false); // choose W/E
         }
 
         calc_t const s1_s2 = math::longitude_distance_signed<units_t>(s1, s2);
 
         if (eq1 || eq2) // Point on level s1 or s2
         {
             return count_info(s1_s2 < c0 ? -1 : 1, // choose W/E
                               longitudes_equal<units_t>(p + pi, (eq1 ? s1 : s2)));
         }
 
         // Point between s1 and s2
         if ( math::sign(s1_p) == math::sign(s1_s2)
           && math::abs(s1_p) < math::abs(s1_s2) )
         {
             return count_info(s1_s2 < c0 ? -2 : 2, false); // choose W/E
         }
 
         calc_t const s1_p_anti = math::longitude_distance_signed<units_t>(s1, p + pi);
 
         // Anti-Point between s1 and s2
         if ( math::sign(s1_p_anti) == math::sign(s1_s2)
           && math::abs(s1_p_anti) < math::abs(s1_s2) )
         {
             return count_info(s1_s2 < c0 ? -2 : 2, true); // choose W/E
         }
 
         return count_info(0, false);
     }
 
 
     // Fix for https://svn.boost.org/trac/boost/ticket/9628
     // For floating point coordinates, the <D> coordinate of a point is compared
     // with the segment's points using some EPS. If the coordinates are "equal"
     // the sides are calculated. Therefore we can treat a segment as a long areal
     // geometry having some width. There is a small ~triangular area somewhere
     // between the segment's effective area and a segment's line used in sides
     // calculation where the segment is on the one side of the line but on the
     // other side of a segment (due to the width).
     // Below picture assuming D = 1, if D = 0 horiz<->vert, E<->N, RIGHT<->UP.
     // For the s1 of a segment going NE the real side is RIGHT but the point may
     // be detected as LEFT, like this:
     //                     RIGHT
     //                 ___----->
     //                  ^      O Pt  __ __
     //                 EPS     __ __
     //                  v__ __ BUT DETECTED AS LEFT OF THIS LINE
     //             _____7
     //       _____/
     // _____/
     // In the code below actually D = 0, so segments are nearly-vertical
     // Called when the point is on the same level as one of the segment's points
     // but the point is not aligned with a vertical segment
     template <typename Point, typename PointOfSegment>
     inline int side_equal(Point const& point,
                           PointOfSegment const& se,
                           count_info const& ci) const
     {
         using scoord_t = coordinate_type_t<PointOfSegment>;
         using units_t = typename geometry::detail::cs_angular_units<Point>::type;
 
         if (math::equals(get<1>(point), get<1>(se)))
         {
             return 0;
         }
 
         // Create a horizontal segment intersecting the original segment's endpoint
         // equal to the point, with the derived direction (E/W).
         PointOfSegment ss1, ss2;
         set<1>(ss1, get<1>(se));
         set<0>(ss1, get<0>(se));
         set<1>(ss2, get<1>(se));
         scoord_t ss20 = get<0>(se);
         if (ci.count > 0)
         {
             ss20 += small_angle<scoord_t, units_t>();
         }
         else
         {
             ss20 -= small_angle<scoord_t, units_t>();
         }
         math::normalize_longitude<units_t>(ss20);
         set<0>(ss2, ss20);
 
         // Check the side using this vertical segment
         return m_side_strategy.apply(ss1, ss2, point);
     }
 
     // 1 deg or pi/180 rad
     template <typename CalcT, typename Units>
     static inline CalcT small_angle()
     {
         typedef math::detail::constants_on_spheroid<CalcT, Units> constants;
 
         return constants::half_period() / CalcT(180);
     }
 
     template <typename Units, typename CalcT>
     static inline bool longitudes_equal(CalcT const& lon1, CalcT const& lon2)
     {
         return math::equals(
                 math::longitude_distance_signed<Units>(lon1, lon2),
                 CalcT(0));
     }
 
     SideStrategy m_side_strategy;
 };
 
 
 } // namespace detail
 #endif // DOXYGEN_NO_DETAIL
 
 
 /*!
 \brief Within detection using winding rule in spherical coordinate system.
 \ingroup strategies
 \tparam Point \tparam_point
 \tparam PointOfSegment \tparam_segment_point
 \tparam CalculationType \tparam_calculation
 
 \qbk{
 [heading See also]
 [link geometry.reference.algorithms.within.within_3_with_strategy within (with strategy)]
 }
  */
 template
 <
     typename Point = void, // for backward compatibility
     typename PointOfSegment = Point, // for backward compatibility
     typename CalculationType = void
 >
 class spherical_winding
     : public within::detail::spherical_winding_base
         <
             side::spherical_side_formula<CalculationType>,
             CalculationType
         >
 {};
 
 
 #ifndef DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
 
 namespace services
 {
 
 template <typename PointLike, typename Geometry, typename AnyTag1, typename AnyTag2>
 struct default_strategy<PointLike, Geometry, AnyTag1, AnyTag2, pointlike_tag, polygonal_tag, spherical_tag, spherical_tag>
 {
     typedef within::spherical_winding<> type;
 };
 
 template <typename PointLike, typename Geometry, typename AnyTag1, typename AnyTag2>
 struct default_strategy<PointLike, Geometry, AnyTag1, AnyTag2, pointlike_tag, linear_tag, spherical_tag, spherical_tag>
 {
     typedef within::spherical_winding<> type;
 };
 
 } // namespace services
 
 #endif
 
 
 }} // namespace strategy::within
 
 
 #ifndef DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
 namespace strategy { namespace covered_by { namespace services
 {
 
 template <typename PointLike, typename Geometry, typename AnyTag1, typename AnyTag2>
 struct default_strategy<PointLike, Geometry, AnyTag1, AnyTag2, pointlike_tag, polygonal_tag, spherical_tag, spherical_tag>
 {
     typedef within::spherical_winding<> type;
 };
 
 template <typename PointLike, typename Geometry, typename AnyTag1, typename AnyTag2>
 struct default_strategy<PointLike, Geometry, AnyTag1, AnyTag2, pointlike_tag, linear_tag, spherical_tag, spherical_tag>
 {
     typedef within::spherical_winding<> type;
 };
 
 }}} // namespace strategy::covered_by::services
 #endif
 
 
 }} // namespace boost::geometry
 
 
 #endif // BOOST_GEOMETRY_STRATEGY_SPHERICAL_POINT_IN_POLY_WINDING_HPP

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