geometry/test/algorithms/buffer/buffer_linestring_geo.cpp

// Boost.Geometry
// Unit Test

// Copyright (c) 2018-2019 Barend Gehrels, 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)

#include "test_buffer_geo.hpp"
#include "aimes_cases.hpp"

// Road with one segment from west to east
static std::string const simplex = "LINESTRING(10.3965628 63.4276786,10.3953134 63.4299634)";

// Road from west to east and from south to north
static std::string const road = "LINESTRING(10.3966569 63.4276957,10.3998059 63.4279182,10.4003964 63.4288424)";

// Road with first a sharp angle to the right, then a rectangular angle to the left, then two obtuse angles
static std::string const sharp = "LINESTRING(10.3939684 63.4255808, 10.3948159 63.4263661, 10.3947354 63.4255918, 10.3950209 63.4255588, 10.3960570 63.4255423, 10.3973017 63.4255570)";

// Linestring forwards and backwards (close to 180 corner)
static std::string const opposite = "LINESTRING(10.4000988 63.4283885,10.4029694 63.4280726,10.4006988 63.4283397)";


template <typename Formula, bool Clockwise, typename PointType>
void test_linestring()
{
    using linestring = bg::model::linestring<PointType>;
    using polygon = bg::model::polygon<PointType, Clockwise>;

    // Because areas can change significantly when another formula is used,
    // use a high tolerance.
    int const points_per_circle = 360;
    ut_settings settings(0.5);

#if defined(BOOST_GEOMETRY_TEST_FAILURES)
    bool const thomas_skip = false;
#else
    // TODO: some cases are missing one or more turns
    bool const thomas_skip = std::is_same<Formula, bg::strategy::thomas>::value;
#endif

    bg::strategies::buffer::geographic<Formula> strategy;
    bg::strategy::buffer::geographic_side_straight<Formula> side;
    bg::strategy::buffer::geographic_join_miter<Formula> join_miter;
    bg::strategy::buffer::geographic_join_miter<Formula> join_miter25(2.5);
    bg::strategy::buffer::geographic_join_round<Formula> join_round(points_per_circle);
    bg::strategy::buffer::geographic_end_round<Formula> end_round(points_per_circle);
    bg::strategy::buffer::geographic_point_circle<Formula> circle(points_per_circle);
    bg::strategy::buffer::end_flat end_flat;

    test_one_geo<linestring, polygon>("simplex_5_8", simplex, strategy, side, circle, join_round, end_flat, 2622.0, 5.0, settings);
    test_one_geo<linestring, polygon>("road_5_flat", road, strategy, side, circle, join_round, end_flat, 2644.0, 5.0, settings);
    test_one_geo<linestring, polygon>("road_5_25_round", road, strategy, side, circle, join_round, end_round, 2016.0, 5.0, settings, 2.5);
    test_one_geo<linestring, polygon>("sharp_5_round", sharp, strategy, side, circle, join_round, end_round, 3090.0, 5.0, settings);
    test_one_geo<linestring, polygon>("sharp_5_miter", sharp, strategy, side, circle, join_miter, end_round, 3181.0, 5.0, settings);
    test_one_geo<linestring, polygon>("sharp_5_miter25", sharp, strategy, side, circle, join_miter25, end_round, 3121.0, 5.0, settings);

    if (! BOOST_GEOMETRY_CONDITION(thomas_skip))
    {
        // Misses an intersection point when using thomas
        test_one_geo<linestring, polygon>("opposite", opposite, strategy, side, circle, join_round, end_round, 1658.0, 5.0, settings);
    }

    {
        auto specific = settings;
        specific.fraction_buffered_points_too_close = 0.3;
        test_one_geo<linestring, polygon>("opposite_miter", opposite, strategy, side, circle, join_miter, end_flat, 1705.0, 5.0, specific);
        test_one_geo<linestring, polygon>("opposite_miter25", opposite, strategy, side, circle, join_miter25, end_flat, 1642.0, 5.0, specific);
    }

    settings.test_area = false;
    int const n = sizeof(testcases_aimes) / sizeof(testcases_aimes[0]);

    // Cases (ouf of 197) where the guessed area estimations are not met.
    // If this needs to be changed, be sure to
    // inspect the result visually on SVG or CSV (QGis).

    // Cases which are curved and have some artefacts (same as for cartesian)
    std::set<int> const cases_with_artefacts{119, 142};
    // Cases which are curved such that the min area is smaller than expected.
    std::set<int> const curved_cases_min_area{86, 181};
    // Cases which are curved such that the max area is larger than expected.
    std::set<int> const curved_cases_max_area{5, 95, 119, 142, 192};
    // Cases which are rounded such that it results in a large area
    std::set<int> const round_cases_max_area{196};
    // Cases which are not yet valid or false negatives
    std::set<int> const round_cases_invalid{143};

    for (auto i = 0; i < n; i++)
    {
        settings.multiplier_min_area
            = curved_cases_min_area.count(i) > 0 ? 0.85
            : ut_settings().multiplier_min_area;

        settings.multiplier_max_area
            = curved_cases_max_area.count(i) > 0 ? 1.2
            : round_cases_max_area.count(i) > 0 ? 1.5
            : ut_settings().multiplier_max_area;

        settings.fraction_buffered_points_too_close
            = cases_with_artefacts.count(i) > 0 ? 0.20
            : ut_settings().fraction_buffered_points_too_close;

        // With miter/flat, the artefacts are more pronounced and there can
        // be more points close than expected.
        auto settings_mf = settings;
        settings_mf.fraction_buffered_points_too_close *= 4.0;

        // With rounded cases, both rounded ends overap, adapt the expected area
        auto settings_rr = settings;
        settings_rr.multiplier_min_area
            = round_cases_max_area.count(i) > 0 ? 0.75
            : settings.multiplier_min_area;

        settings_rr.set_test_validity(round_cases_invalid.count(i) == 0);

        if (i != 181)
        {
            // 181 fails, it should generate a hole, but instead that is the outer ring now.
            test_one_geo<linestring, polygon>("aimes_" + std::to_string(i) + "_rr", testcases_aimes[i],
                strategy, side, circle, join_round, end_round, -1, 25.0, settings_rr);
        }
        test_one_geo<linestring, polygon>("aimes_" + std::to_string(i) + "_rf", testcases_aimes[i],
            strategy, side, circle, join_round, end_flat, -1, 25.0, settings);
        test_one_geo<linestring, polygon>("aimes_" + std::to_string(i) + "_mf", testcases_aimes[i],
            strategy, side, circle, join_miter, end_flat, -1, 25.0, settings_mf);
    }
}

int test_main(int, char* [])
{
    BoostGeometryWriteTestConfiguration();

    test_linestring<bg::strategy::andoyer, true, bg::model::point<default_test_type, 2, bg::cs::geographic<bg::degree> > >();
    test_linestring<bg::strategy::thomas, true, bg::model::point<default_test_type, 2, bg::cs::geographic<bg::degree> > >();

#if ! defined(BOOST_GEOMETRY_TEST_ONLY_ONE_TYPE)
    test_linestring<bg::strategy::andoyer, true, bg::model::point<long double, 2, bg::cs::geographic<bg::degree> > >();
#endif

    return 0;
}