mapnik/test/unit/geometry/closest_point.cpp

#include "catch.hpp"

#include <mapnik/geometry/closest_point.hpp>

TEST_CASE("geometry closest point")
{
#if BOOST_VERSION >= 106200

    SECTION("geometry_empty")
    {
        mapnik::geometry::point<double> pt(0, 0);
        mapnik::geometry::geometry_empty empty;
        auto result = mapnik::geometry::closest_point(empty, pt);
        REQUIRE(result.x == 0.0);
        REQUIRE(result.y == 0.0);
        REQUIRE(result.distance == -1.0);
    }

    SECTION("point")
    {
        mapnik::geometry::point<double> pt(0, 0);
        mapnik::geometry::point<double> geom(3.0, 4.0);
        auto result = mapnik::geometry::closest_point(geom, pt);
        REQUIRE(result.x == geom.x);
        REQUIRE(result.y == geom.y);
        REQUIRE(result.distance == 5.0);
    }

    SECTION("linestring")
    {
        mapnik::geometry::line_string<double> line;
        line.emplace_back(0, 0);
        line.emplace_back(0, 100);
        line.emplace_back(100, 100);
        line.emplace_back(100, 0);
        mapnik::geometry::point<double> pt(50, 50);
        auto result = mapnik::geometry::closest_point(line, pt);
        REQUIRE(result.x == 0.0);
        REQUIRE(result.y == 50.0);
        REQUIRE(result.distance == 50.0);
    }

    SECTION("polygon")
    {
        mapnik::geometry::polygon<double> poly;
        mapnik::geometry::linear_ring<double> ring;
        ring.emplace_back(0, 0);
        ring.emplace_back(1, 0);
        ring.emplace_back(1, 1);
        ring.emplace_back(0, 1);
        ring.emplace_back(0, 0);
        poly.push_back(std::move(ring));

        {
            // point inside polygon
            mapnik::geometry::point<double> pt{0.5, 0.25};
            auto result = mapnik::geometry::closest_point(poly, pt);
            REQUIRE(result.x == 0.5);
            REQUIRE(result.y == 0.25);
            REQUIRE(result.distance == 0.0);
        }
        {
            // point outside polygon
            mapnik::geometry::point<double> pt{1.25, 0.5};
            auto result = mapnik::geometry::closest_point(poly, pt);
            REQUIRE(result.x == 1.0);
            REQUIRE(result.y == 0.5);
            REQUIRE(result.distance == 0.25);
        }
        {
            // point outside polygon
            mapnik::geometry::point<double> pt{4.0, 5.0};
            auto result = mapnik::geometry::closest_point(poly, pt);
            REQUIRE(result.x == 1.0);
            REQUIRE(result.y == 1.0);
            REQUIRE(result.distance == 5.0);
        }
        {
            // point on polygon boundary
            mapnik::geometry::point<double> pt{0, 0.4};
            auto result = mapnik::geometry::closest_point(poly, pt);
            REQUIRE(result.x == 0.0);
            REQUIRE(result.y == 0.4);
            REQUIRE(result.distance == 0.0);
        }
    }
#endif
}