view release on metacpan or  search on metacpan

src/boost/geometry/strategies/cartesian/cart_intersect.hpp  view on Meta::CPAN

        int corrected = 0;
        if (sides.one_touching<0>())
        {
            if (point_equals(
                        select(sides.zero_index<0>(), a),
                        select(0, b)
                    ))
            {
                sides.correct_to_zero<1, 0>();
                corrected = 1;
            }
            if (point_equals
                    (
                        select(sides.zero_index<0>(), a),
                        select(1, b)
                    ))
            {
                sides.correct_to_zero<1, 1>();
                corrected = 2;
            }
        }
        else if (sides.one_touching<1>())
        {
            if (point_equals(
                        select(sides.zero_index<1>(), b),
                        select(0, a)
                    ))
            {
                sides.correct_to_zero<0, 0>();
                corrected = 3;
            }
            if (point_equals
                    (
                        select(sides.zero_index<1>(), b),
                        select(1, a)
                    ))
            {
                sides.correct_to_zero<0, 1>();
                corrected = 4;
            }
        }

        return corrected == 0;
    }

    static inline bool robustness_verify_disjoint_at_one_collinear(
                segment_type1 const& a, segment_type2 const& b,
                side_info const& sides)
    {
        if (sides.one_of_all_zero())
        {
            if (verify_disjoint<0>(a, b) || verify_disjoint<1>(a, b))
            {
                return true;
            }
        }
        return false;
    }


    // If r is one, or zero, segments should meet and their endpoints.
    // Robustness issue: check if this is really the case.
    // It turns out to be no problem, see buffer test #rt_s1 (and there are many cases generated)
    // It generates an "ends in the middle" situation which is correct.
    template <typename T, typename R>
    static inline void robustness_handle_meeting(segment_type1 const& a, segment_type2 const& b,
                side_info& sides,
                T const& dx_a, T const& dy_a, T const& wx, T const& wy,
                T const& d, R const& r)
    {
        return;

        T const db = geometry::detail::determinant<T>(dx_a, dy_a, wx, wy);

        R const zero = 0;
        R const one = 1;
        if (math::equals(r, zero) || math::equals(r, one))
        {
            R rb = db / d;
            if (rb <= 0 || rb >= 1 || math::equals(rb, 0) || math::equals(rb, 1))
            {
                if (sides.one_zero<0>() && ! sides.one_zero<1>()) // or vice versa
                {
#if defined(BOOST_GEOMETRY_COUNT_INTERSECTION_EQUAL)
                    extern int g_count_intersection_equal;
                    g_count_intersection_equal++;
#endif
                    sides.debug();
                    std::cout << "E r=" << r << " r.b=" << rb << " ";
                }
            }
        }
    }

    template <std::size_t Dimension>
    static inline bool verify_disjoint(segment_type1 const& a,
                    segment_type2 const& b)
    {
        coordinate_type a_1, a_2, b_1, b_2;
        bool a_swapped = false, b_swapped = false;
        detail::segment_arrange<Dimension>(a, a_1, a_2, a_swapped);
        detail::segment_arrange<Dimension>(b, b_1, b_2, b_swapped);
        return math::smaller(a_2, b_1) || math::larger(a_1, b_2);
    }

    template <typename Segment>
    static inline typename point_type<Segment>::type select(int index, Segment const& segment)
    {
        return index == 0 
            ? detail::get_from_index<0>(segment)
            : detail::get_from_index<1>(segment)
            ;
    }

    // We cannot use geometry::equals here. Besides that this will be changed
    // to compare segment-coordinate-values directly (not necessary to retrieve point first)
    template <typename Point1, typename Point2>
    static inline bool point_equals(Point1 const& point1, Point2 const& point2)
    {
        return math::equals(get<0>(point1), get<0>(point2))
            && math::equals(get<1>(point1), get<1>(point2))