// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2007-2014 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2013-2023 Adam Wulkiewicz, Lodz, Poland.
// This file was modified by Oracle on 2014-2021.
// Modifications copyright (c) 2014-2021, Oracle and/or its affiliates.
// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
// 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_STRATEGIES_CARTESIAN_INTERSECTION_HPP
#define BOOST_GEOMETRY_STRATEGIES_CARTESIAN_INTERSECTION_HPP
#include <algorithm>
#include <boost/geometry/core/exception.hpp>
#include <boost/geometry/geometries/concepts/point_concept.hpp>
#include <boost/geometry/geometries/concepts/segment_concept.hpp>
#include <boost/geometry/geometries/segment.hpp>
#include <boost/geometry/arithmetic/determinant.hpp>
#include <boost/geometry/algorithms/detail/assign_values.hpp>
#include <boost/geometry/algorithms/detail/assign_indexed_point.hpp>
#include <boost/geometry/algorithms/detail/equals/point_point.hpp>
#include <boost/geometry/algorithms/detail/recalculate.hpp>
#include <boost/geometry/util/math.hpp>
#include <boost/geometry/util/numeric_cast.hpp>
#include <boost/geometry/util/promote_integral.hpp>
#include <boost/geometry/util/select_calculation_type.hpp>
#include <boost/geometry/strategy/cartesian/area.hpp>
#include <boost/geometry/strategy/cartesian/envelope.hpp>
#include <boost/geometry/strategy/cartesian/expand_box.hpp>
#include <boost/geometry/strategy/cartesian/expand_segment.hpp>
#include <boost/geometry/strategies/cartesian/disjoint_box_box.hpp>
#include <boost/geometry/strategies/cartesian/disjoint_segment_box.hpp>
#include <boost/geometry/strategies/cartesian/distance_pythagoras.hpp>
#include <boost/geometry/strategies/cartesian/point_in_point.hpp>
#include <boost/geometry/strategies/cartesian/point_in_poly_winding.hpp>
#include <boost/geometry/strategies/covered_by.hpp>
#include <boost/geometry/strategies/intersection.hpp>
#include <boost/geometry/strategies/intersection_result.hpp>
#include <boost/geometry/strategies/side.hpp>
#include <boost/geometry/strategies/side_info.hpp>
#include <boost/geometry/strategies/within.hpp>
#include <boost/geometry/policies/robustness/rescale_policy_tags.hpp>
#include <boost/geometry/policies/robustness/robust_point_type.hpp>
#if defined(BOOST_GEOMETRY_DEBUG_ROBUSTNESS)
# include <boost/geometry/io/wkt/write.hpp>
#endif
namespace boost { namespace geometry
{
namespace strategy { namespace intersection
{
namespace detail_usage
{
// When calculating the intersection, the information of "a" or "b" can be used.
// Theoretically this gives equal results, but due to floating point precision
// there might be tiny differences. These are edge cases.
// This structure is to determine if "a" or "b" should be used.
// Prefer the segment closer to the endpoint.
// If both are about equally close, then prefer the longer segment
// To avoid hard thresholds, behavior is made fluent.
// Calculate comparable length indications,
// the longer the segment (relatively), the lower the value
// such that the shorter lengths are evaluated higher and will
// be preferred.
template <bool IsArithmetic>
struct use_a
{
template <typename Ct, typename Ev>
static bool apply(Ct const& cla, Ct const& clb, Ev const& eva, Ev const& evb)
{
auto const clm = (std::max)(cla, clb);
if (clm <= 0)
{
return true;
}
// Relative comparible length
auto const rcla = Ct(1.0) - cla / clm;
auto const rclb = Ct(1.0) - clb / clm;
// Multipliers for edgevalue (ev) and relative comparible length (rcl)
// They determine the balance between edge value (should be larger)
// and segment length. In 99.9xx% of the cases there is no difference
// at all (if either a or b is used). Therefore the values of the
// constants are not sensitive for the majority of the situations.
// One known case is #mysql_23023665_6 (difference) which needs mev >= 2
Ev const mev = 5;
Ev const mrcl = 1;
return mev * eva + mrcl * rcla > mev * evb + mrcl * rclb;
}
};
// Specialization for non arithmetic types. They will always use "a"
template <>
struct use_a<false>
{
template <typename Ct, typename Ev>
static bool apply(Ct const& , Ct const& , Ev const& , Ev const& )
{
return true;
}
};
}
/*!
\see http://mathworld.wolfram.com/Line-LineIntersection.html
*/
template
<
typename CalculationType = void
>
struct cartesian_segments
{
typedef cartesian_tag cs_tag;
template <typename CoordinateType, typename SegmentRatio>
struct segment_intersection_info
{
private :
typedef typename select_most_precise
<
CoordinateType, double
>::type promoted_type;
promoted_type comparable_length_a() const
{
return dx_a * dx_a + dy_a * dy_a;
}
promoted_type comparable_length_b() const
{
return dx_b * dx_b + dy_b * dy_b;
}
template <typename Point, typename Segment1, typename Segment2>
void assign_a(Point& point, Segment1 const& a, Segment2 const& ) const
{
assign(point, a, dx_a, dy_a, robust_ra);
}
template <typename Point, typename Segment1, typename Segment2>
void assign_b(Point& point, Segment1 const& , Segment2 const& b) const
{
assign(point, b, dx_b, dy_b, robust_rb);
}
template <typename Point, typename Segment>
void assign(Point& point, Segment const& segment,
CoordinateType const& dx, CoordinateType const& dy,
SegmentRatio const& ratio) const
{
// Calculate the intersection point based on segment_ratio
// The division, postponed until here, is done now. In case of integer this
// results in an integer which rounds to the nearest integer.
BOOST_GEOMETRY_ASSERT(ratio.denominator() != typename SegmentRatio::int_type(0));
typedef typename promote_integral<CoordinateType>::type calc_type;
calc_type const numerator
= util::numeric_cast<calc_type>(ratio.numerator());
calc_type const denominator
= util::numeric_cast<calc_type>(ratio.denominator());
calc_type const dx_calc = util::numeric_cast<calc_type>(dx);
calc_type const dy_calc = util::numeric_cast<calc_type>(dy);
set<0>(point, get<0, 0>(segment)
+ util::numeric_cast<CoordinateType>(
math::divide<calc_type>(numerator * dx_calc, denominator)));
set<1>(point, get<0, 1>(segment)
+ util::numeric_cast<CoordinateType>(
math::divide<calc_type>(numerator * dy_calc, denominator)));
}
template <int Index, int Dim, typename Point, typename Segment>
static bool exceeds_side_in_dimension(Point& p, Segment const& s)
{
// Situation a (positive)
// 0>-------------->1 segment
// * point left of segment<I> in D x or y
// Situation b (negative)
// 1<--------------<0 segment
// * point right of segment<I>
// Situation c (degenerate), return false (check other dimension)
auto const& c = get<Dim>(p);
auto const& c0 = get<Index, Dim>(s);
auto const& c1 = get<1 - Index, Dim>(s);
return c0 < c1 ? math::smaller(c, c0)
: c0 > c1 ? math::larger(c, c0)
: false;
}
template <int Index, typename Point, typename Segment>
static bool exceeds_side_of_segment(Point& p, Segment const& s)
{
return exceeds_side_in_dimension<Index, 0>(p, s)
|| exceeds_side_in_dimension<Index, 1>(p, s);
}
template <typename Point, typename Segment>
static void assign_if_exceeds(Point& point, Segment const& s)
{
if (exceeds_side_of_segment<0>(point, s))
{
detail::assign_point_from_index<0>(s, point);
}
else if (exceeds_side_of_segment<1>(point, s))
{
detail::assign_point_from_index<1>(s, point);
}
}
public :
template <typename Point, typename Segment1, typename Segment2>
void calculate(Point& point, Segment1 const& a, Segment2 const& b) const
{
bool const use_a
= detail_usage::use_a
<
std::is_arithmetic<CoordinateType>::value
>::apply(comparable_length_a(), comparable_length_b(),
robust_ra.edge_value(), robust_rb.edge_value());
if (use_a)
{
assign_a(point, a, b);
}
else
{
assign_b(point, a, b);
}
#ifndef BOOST_GEOMETRY_USE_RESCALING
// Verify nearly collinear cases (the threshold is arbitrary
// but influences performance). If the intersection is located
// outside the segments, then it should be moved.
if (robust_ra.possibly_collinear(1.0e-3)
&& robust_rb.possibly_collinear(1.0e-3))
{
// The segments are nearly collinear and because of the calculation
// method with very small denominator, the IP appears outside the
// segment(s). Correct it to the end point.
// Because they are nearly collinear, it doesn't really matter to
// to which endpoint (or it is corrected twice).
assign_if_exceeds(point, a);
assign_if_exceeds(point, b);
}
#endif
}
CoordinateType dx_a, dy_a;
CoordinateType dx_b, dy_b;
SegmentRatio robust_ra;
SegmentRatio robust_rb;
};
template <typename D, typename W, typename ResultType>
static inline void cramers_rule(D const& dx_a, D const& dy_a,
D const& dx_b, D const& dy_b, W const& wx, W const& wy,
// out:
ResultType& nominator, ResultType& denominator)
{
// Cramers rule
nominator = geometry::detail::determinant<ResultType>(dx_b, dy_b, wx, wy);
denominator = geometry::detail::determinant<ResultType>(dx_a, dy_a, dx_b, dy_b);
// Ratio r = nominator/denominator
// Collinear if denominator == 0, intersecting if 0 <= r <= 1
// IntersectionPoint = (x1 + r * dx_a, y1 + r * dy_a)
}
// Version for non-rescaled policies
template
<
typename UniqueSubRange1,
typename UniqueSubRange2,
typename Policy
>
static inline typename Policy::return_type
apply(UniqueSubRange1 const& range_p,
UniqueSubRange2 const& range_q,
Policy const& policy)
{
// Pass the same ranges both as normal ranges and as modelled ranges
return apply(range_p, range_q, policy, range_p, range_q);
}
// Version for non rescaled versions.
// The "modelled" parameter might be rescaled (will be removed later)
template
<
typename UniqueSubRange1,
typename UniqueSubRange2,
typename Policy,
typename ModelledUniqueSubRange1,
typename ModelledUniqueSubRange2
>
static inline typename Policy::return_type
apply(UniqueSubRange1 const& range_p,
UniqueSubRange2 const& range_q,
Policy const& policy,
ModelledUniqueSubRange1 const& modelled_range_p,
ModelledUniqueSubRange2 const& modelled_range_q)
{
typedef typename UniqueSubRange1::point_type point1_type;
typedef typename UniqueSubRange2::point_type point2_type;
BOOST_CONCEPT_ASSERT( (concepts::ConstPoint<point1_type>) );
BOOST_CONCEPT_ASSERT( (concepts::ConstPoint<point2_type>) );
point1_type const& p1 = range_p.at(0);
point1_type const& p2 = range_p.at(1);
point2_type const& q1 = range_q.at(0);
point2_type const& q2 = range_q.at(1);
// Declare segments, currently necessary for the policies
// (segment_crosses, segment_colinear, degenerate, one_degenerate, etc)
model::referring_segment<point1_type const> const p(p1, p2);
model::referring_segment<point2_type const> const q(q1, q2);
typedef typename select_most_precise
<
typename geometry::coordinate_type<typename ModelledUniqueSubRange1::point_type>::type,
typename geometry::coordinate_type<typename ModelledUniqueSubRange1::point_type>::type
>::type modelled_coordinate_type;
typedef segment_ratio<modelled_coordinate_type> ratio_type;
segment_intersection_info
<
typename select_calculation_type<point1_type, point2_type, CalculationType>::type,
ratio_type
> sinfo;
sinfo.dx_a = get<0>(p2) - get<0>(p1); // distance in x-dir
sinfo.dx_b = get<0>(q2) - get<0>(q1);
sinfo.dy_a = get<1>(p2) - get<1>(p1); // distance in y-dir
sinfo.dy_b = get<1>(q2) - get<1>(q1);
return unified<ratio_type>(sinfo, p, q, policy, modelled_range_p, modelled_range_q);
}
//! Returns true if two segments do not overlap.
//! If not, then no further calculations need to be done.
template
<
std::size_t Dimension,
typename PointP,
typename PointQ
>
static inline bool disjoint_by_range(PointP const& p1, PointP const& p2,
PointQ const& q1, PointQ const& q2)
{
auto minp = get<Dimension>(p1);
auto maxp = get<Dimension>(p2);
auto minq = get<Dimension>(q1);
auto maxq = get<Dimension>(q2);
if (minp > maxp)
{
std::swap(minp, maxp);
}
if (minq > maxq)
{
std::swap(minq, maxq);
}
// In this case, max(p) < min(q)
// P Q
// <-------> <------->
// (and the space in between is not extremely small)
return math::smaller(maxp, minq) || math::smaller(maxq, minp);
}
// Implementation for either rescaled or non rescaled versions.
template
<
typename RatioType,
typename SegmentInfo,
typename Segment1,
typename Segment2,
typename Policy,
typename UniqueSubRange1,
typename UniqueSubRange2
>
static inline typename Policy::return_type
unified(SegmentInfo& sinfo,
Segment1 const& p, Segment2 const& q, Policy const&,
UniqueSubRange1 const& range_p,
UniqueSubRange2 const& range_q)
{
typedef typename UniqueSubRange1::point_type point1_type;
typedef typename UniqueSubRange2::point_type point2_type;
typedef typename select_most_precise
<
typename geometry::coordinate_type<point1_type>::type,
typename geometry::coordinate_type<point2_type>::type
>::type coordinate_type;
point1_type const& p1 = range_p.at(0);
point1_type const& p2 = range_p.at(1);
point2_type const& q1 = range_q.at(0);
point2_type const& q2 = range_q.at(1);
bool const p_is_point = equals_point_point(p1, p2);
bool const q_is_point = equals_point_point(q1, q2);
if (p_is_point && q_is_point)
{
return equals_point_point(p1, q2)
? Policy::degenerate(p, true)
: Policy::disjoint()
;
}
if (disjoint_by_range<0>(p1, p2, q1, q2)
|| disjoint_by_range<1>(p1, p2, q1, q2))
{
return Policy::disjoint();
}
using side_strategy_type
= typename side::services::default_strategy
<cartesian_tag, CalculationType>::type;
side_info sides;
sides.set<0>(side_strategy_type::apply(q1, q2, p1),
side_strategy_type::apply(q1, q2, p2));
if (sides.same<0>())
{
// Both points are at same side of other segment, we can leave
return Policy::disjoint();
}
sides.set<1>(side_strategy_type::apply(p1, p2, q1),
side_strategy_type::apply(p1, p2, q2));
if (sides.same<1>())
{
// Both points are at same side of other segment, we can leave
return Policy::disjoint();
}
bool collinear = sides.collinear();
//TODO: remove this when rescaling is removed
// Calculate the differences again
// (for rescaled version, this is different from dx_p etc)
coordinate_type const dx_p = get<0>(p2) - get<0>(p1);
coordinate_type const dx_q = get<0>(q2) - get<0>(q1);
coordinate_type const dy_p = get<1>(p2) - get<1>(p1);
coordinate_type const dy_q = get<1>(q2) - get<1>(q1);
// r: ratio 0-1 where intersection divides A/B
// (only calculated for non-collinear segments)
if (! collinear)
{
coordinate_type denominator_a, nominator_a;
coordinate_type denominator_b, nominator_b;
cramers_rule(dx_p, dy_p, dx_q, dy_q,
get<0>(p1) - get<0>(q1),
get<1>(p1) - get<1>(q1),
nominator_a, denominator_a);
cramers_rule(dx_q, dy_q, dx_p, dy_p,
get<0>(q1) - get<0>(p1),
get<1>(q1) - get<1>(p1),
nominator_b, denominator_b);
math::detail::equals_factor_policy<coordinate_type>
policy(dx_p, dy_p, dx_q, dy_q);
coordinate_type const zero = 0;
if (math::detail::equals_by_policy(denominator_a, zero, policy)
|| math::detail::equals_by_policy(denominator_b, zero, policy))
{
// If this is the case, no rescaling is done for FP precision.
// We set it to collinear, but it indicates a robustness issue.
sides.set<0>(0, 0);
sides.set<1>(0, 0);
collinear = true;
}
else
{
sinfo.robust_ra.assign(nominator_a, denominator_a);
sinfo.robust_rb.assign(nominator_b, denominator_b);
}
}
if (collinear)
{
std::pair<bool, bool> const collinear_use_first
= is_x_more_significant(geometry::math::abs(dx_p),
geometry::math::abs(dy_p),
geometry::math::abs(dx_q),
geometry::math::abs(dy_q),
p_is_point, q_is_point);
if (collinear_use_first.second)
{
// Degenerate cases: segments of single point, lying on other segment, are not disjoint
// This situation is collinear too
if (collinear_use_first.first)
{
return relate_collinear<0, Policy, RatioType>(p, q,
p1, p2, q1, q2,
p_is_point, q_is_point);
}
else
{
// Y direction contains larger segments (maybe dx is zero)
return relate_collinear<1, Policy, RatioType>(p, q,
p1, p2, q1, q2,
p_is_point, q_is_point);
}
}
}
if (equals_point_point(p1, q1) || equals_point_point(p1, q2))
{
return Policy::segments_share_common_point(sides, sinfo, p1);
}
if (equals_point_point(p2, q1) || equals_point_point(p2, q2))
{
return Policy::segments_share_common_point(sides, sinfo, p2);
}
return Policy::segments_crosses(sides, sinfo, p, q);
}
private:
// first is true if x is more significant
// second is true if the more significant difference is not 0
template <typename CoordinateType>
static inline std::pair<bool, bool>
is_x_more_significant(CoordinateType const& abs_dx_a,
CoordinateType const& abs_dy_a,
CoordinateType const& abs_dx_b,
CoordinateType const& abs_dy_b,
bool const a_is_point,
bool const b_is_point)
{
//BOOST_GEOMETRY_ASSERT_MSG(!(a_is_point && b_is_point), "both segments shouldn't be degenerated");
// for degenerated segments the second is always true because this function
// shouldn't be called if both segments were degenerated
if (a_is_point)
{
return std::make_pair(abs_dx_b >= abs_dy_b, true);
}
else if (b_is_point)
{
return std::make_pair(abs_dx_a >= abs_dy_a, true);
}
else
{
CoordinateType const min_dx = (std::min)(abs_dx_a, abs_dx_b);
CoordinateType const min_dy = (std::min)(abs_dy_a, abs_dy_b);
return min_dx == min_dy ?
std::make_pair(true, min_dx > CoordinateType(0)) :
std::make_pair(min_dx > min_dy, true);
}
}
template
<
std::size_t Dimension,
typename Policy,
typename RatioType,
typename Segment1,
typename Segment2,
typename RobustPoint1,
typename RobustPoint2
>
static inline typename Policy::return_type
relate_collinear(Segment1 const& a,
Segment2 const& b,
RobustPoint1 const& robust_a1, RobustPoint1 const& robust_a2,
RobustPoint2 const& robust_b1, RobustPoint2 const& robust_b2,
bool a_is_point, bool b_is_point)
{
if (a_is_point)
{
return relate_one_degenerate<Policy, RatioType>(a,
get<Dimension>(robust_a1),
get<Dimension>(robust_b1), get<Dimension>(robust_b2),
true);
}
if (b_is_point)
{
return relate_one_degenerate<Policy, RatioType>(b,
get<Dimension>(robust_b1),
get<Dimension>(robust_a1), get<Dimension>(robust_a2),
false);
}
return relate_collinear<Policy, RatioType>(a, b,
get<Dimension>(robust_a1),
get<Dimension>(robust_a2),
get<Dimension>(robust_b1),
get<Dimension>(robust_b2));
}
/// Relate segments known collinear
template
<
typename Policy,
typename RatioType,
typename Segment1,
typename Segment2,
typename Type1,
typename Type2
>
static inline typename Policy::return_type
relate_collinear(Segment1 const& a, Segment2 const& b,
Type1 oa_1, Type1 oa_2,
Type2 ob_1, Type2 ob_2)
{
// Calculate the ratios where a starts in b, b starts in a
// a1--------->a2 (2..7)
// b1----->b2 (5..8)
// length_a: 7-2=5
// length_b: 8-5=3
// b1 is located w.r.t. a at ratio: (5-2)/5=3/5 (on a)
// b2 is located w.r.t. a at ratio: (8-2)/5=6/5 (right of a)
// a1 is located w.r.t. b at ratio: (2-5)/3=-3/3 (left of b)
// a2 is located w.r.t. b at ratio: (7-5)/3=2/3 (on b)
// A arrives (a2 on b), B departs (b1 on a)
// If both are reversed:
// a2<---------a1 (7..2)
// b2<-----b1 (8..5)
// length_a: 2-7=-5
// length_b: 5-8=-3
// b1 is located w.r.t. a at ratio: (8-7)/-5=-1/5 (before a starts)
// b2 is located w.r.t. a at ratio: (5-7)/-5=2/5 (on a)
// a1 is located w.r.t. b at ratio: (7-8)/-3=1/3 (on b)
// a2 is located w.r.t. b at ratio: (2-8)/-3=6/3 (after b ends)
// If both one is reversed:
// a1--------->a2 (2..7)
// b2<-----b1 (8..5)
// length_a: 7-2=+5
// length_b: 5-8=-3
// b1 is located w.r.t. a at ratio: (8-2)/5=6/5 (after a ends)
// b2 is located w.r.t. a at ratio: (5-2)/5=3/5 (on a)
// a1 is located w.r.t. b at ratio: (2-8)/-3=6/3 (after b ends)
// a2 is located w.r.t. b at ratio: (7-8)/-3=1/3 (on b)
Type1 const length_a = oa_2 - oa_1; // no abs, see above
Type2 const length_b = ob_2 - ob_1;
RatioType ra_from(oa_1 - ob_1, length_b);
RatioType ra_to(oa_2 - ob_1, length_b);
RatioType rb_from(ob_1 - oa_1, length_a);
RatioType rb_to(ob_2 - oa_1, length_a);
// use absolute measure to detect endpoints intersection
// NOTE: it'd be possible to calculate bx_wrt_a using ax_wrt_b values
int const a1_wrt_b = position_value(oa_1, ob_1, ob_2);
int const a2_wrt_b = position_value(oa_2, ob_1, ob_2);
int const b1_wrt_a = position_value(ob_1, oa_1, oa_2);
int const b2_wrt_a = position_value(ob_2, oa_1, oa_2);
// fix the ratios if necessary
// CONSIDER: fixing ratios also in other cases, if they're inconsistent
// e.g. if ratio == 1 or 0 (so IP at the endpoint)
// but position value indicates that the IP is in the middle of the segment
// because one of the segments is very long
// In such case the ratios could be moved into the middle direction
// by some small value (e.g. EPS+1ULP)
if (a1_wrt_b == 1)
{
ra_from.assign(0, 1);
rb_from.assign(0, 1);
}
else if (a1_wrt_b == 3)
{
ra_from.assign(1, 1);
rb_to.assign(0, 1);
}
if (a2_wrt_b == 1)
{
ra_to.assign(0, 1);
rb_from.assign(1, 1);
}
else if (a2_wrt_b == 3)
{
ra_to.assign(1, 1);
rb_to.assign(1, 1);
}
if ((a1_wrt_b < 1 && a2_wrt_b < 1) || (a1_wrt_b > 3 && a2_wrt_b > 3))
//if ((ra_from.left() && ra_to.left()) || (ra_from.right() && ra_to.right()))
{
return Policy::disjoint();
}
bool const opposite = math::sign(length_a) != math::sign(length_b);
return Policy::segments_collinear(a, b, opposite,
a1_wrt_b, a2_wrt_b, b1_wrt_a, b2_wrt_a,
ra_from, ra_to, rb_from, rb_to);
}
/// Relate segments where one is degenerate
template
<
typename Policy,
typename RatioType,
typename DegenerateSegment,
typename Type1,
typename Type2
>
static inline typename Policy::return_type
relate_one_degenerate(DegenerateSegment const& degenerate_segment,
Type1 d, Type2 s1, Type2 s2,
bool a_degenerate)
{
// Calculate the ratios where ds starts in s
// a1--------->a2 (2..6)
// b1/b2 (4..4)
// Ratio: (4-2)/(6-2)
RatioType const ratio(d - s1, s2 - s1);
if (!ratio.on_segment())
{
return Policy::disjoint();
}
return Policy::one_degenerate(degenerate_segment, ratio, a_degenerate);
}
template <typename ProjCoord1, typename ProjCoord2>
static inline int position_value(ProjCoord1 const& ca1,
ProjCoord2 const& cb1,
ProjCoord2 const& cb2)
{
// S1x 0 1 2 3 4
// S2 |---------->
return math::equals(ca1, cb1) ? 1
: math::equals(ca1, cb2) ? 3
: cb1 < cb2 ?
( ca1 < cb1 ? 0
: ca1 > cb2 ? 4
: 2 )
: ( ca1 > cb1 ? 0
: ca1 < cb2 ? 4
: 2 );
}
template <typename Point1, typename Point2>
static inline bool equals_point_point(Point1 const& point1, Point2 const& point2)
{
return strategy::within::cartesian_point_point::apply(point1, point2);
}
};
#ifndef DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
namespace services
{
template <typename CalculationType>
struct default_strategy<cartesian_tag, CalculationType>
{
typedef cartesian_segments<CalculationType> type;
};
} // namespace services
#endif // DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
}} // namespace strategy::intersection
namespace strategy
{
namespace within { namespace services
{
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, linear_tag, linear_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, linear_tag, polygonal_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, polygonal_tag, linear_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, polygonal_tag, polygonal_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
}} // within::services
namespace covered_by { namespace services
{
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, linear_tag, linear_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, linear_tag, polygonal_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, polygonal_tag, linear_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
template <typename Geometry1, typename Geometry2, typename AnyTag1, typename AnyTag2>
struct default_strategy<Geometry1, Geometry2, AnyTag1, AnyTag2, polygonal_tag, polygonal_tag, cartesian_tag, cartesian_tag>
{
typedef strategy::intersection::cartesian_segments<> type;
};
}} // within::services
} // strategy
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_STRATEGIES_CARTESIAN_INTERSECTION_HPP