mapnik/test/unit/geometry/geometry_strategy_test.cpp

#include "catch.hpp"
#include "geometry_equal.hpp"

#include <mapnik/geometry.hpp>
#include <mapnik/projection.hpp>
#include <mapnik/proj_transform.hpp>
#include <mapnik/view_transform.hpp>
#include <mapnik/geometry/transform.hpp>
#include <mapnik/geometry/strategy.hpp>
#include <mapnik/proj_strategy.hpp>
#include <mapnik/view_strategy.hpp>

TEST_CASE("geometry strategy tests")
{
    SECTION("proj and view strategy")
    {
        using namespace mapnik::geometry;
        mapnik::box2d<double> e(-20037508.342789, -20037508.342789, 20037508.342789, 20037508.342789);
        mapnik::view_transform vt(256, 256, e);
        mapnik::view_strategy vs(vt);
        mapnik::unview_strategy uvs(vt);
        mapnik::projection source("epsg:4326");
        mapnik::projection dest("epsg:3857");
        mapnik::proj_transform proj_trans(source, dest);
        mapnik::proj_transform proj_trans_rev(dest, source);
        mapnik::proj_strategy ps(proj_trans);
        mapnik::proj_strategy ps_rev(proj_trans_rev);
        {
            // Test first that proj strategy works properly
            point<double> p1(-97.553098, 35.523105);
            point<double> r1(-1.08596e+07, 4.2352e+06);
            point<double> p3 = transform<double>(p1, ps);
            assert_g_equal(r1, p3);
        }
        {
            // Test next that view_strategy works
            point<double> p1(-1.08596e+07, 4.2352e+06);
            point<double> r1(58.6287, 100.945);
            point<double> p3 = transform<double>(p1, vs);
            assert_g_equal(r1, p3);
        }
        {
            // Test next that view_strategy works as single process in strategy group
            point<double> p1(-1.08596e+07, 4.2352e+06);
            point<double> r1(58.6287, 100.945);
            using sg_type = strategy_group<mapnik::view_strategy>;
            sg_type sg(vs);
            point<double> p3 = transform<double>(p1, sg);
            assert_g_equal(r1, p3);
        }
        {
            // Test that both work grouped together in strategy group
            using sg_type = strategy_group<mapnik::proj_strategy, mapnik::view_strategy>;
            sg_type sg(ps, vs);
            point<double> p1(-97.553098, 35.523105);
            point<double> r1(58.6287, 100.945);
            point<double> p3 = transform<double>(p1, sg);
            assert_g_equal(r1, p3);
        }
        {
            // Test that both work grouped together passing in geometry
            using sg_type = strategy_group<mapnik::proj_strategy, mapnik::view_strategy>;
            sg_type sg(ps, vs);
            geometry<double> p1(point<double>(-97.553098, 35.523105));
            point<double> r1(58.6287, 100.945);
            geometry<double> p2 = transform<double>(p1, sg);
            REQUIRE(p2.is<point<double>>());
            point<double> p3 = mapnik::util::get<point<double>>(p2);
            assert_g_equal(r1, p3);
        }
        {
            // Test that it works pulling back int
            using sg_type = strategy_group<mapnik::proj_strategy, mapnik::view_strategy>;
            sg_type sg(ps, vs);
            geometry<double> p1(point<double>(-97.553098, 35.523105));
            point<std::int64_t> r1(58, 100);
            geometry<std::int64_t> p2 = transform<std::int64_t>(p1, sg);
            REQUIRE(p2.is<point<std::int64_t>>());
            point<std::int64_t> p3 = mapnik::util::get<point<std::int64_t>>(p2);
            assert_g_equal(r1, p3);
        }
        {
            // Test with scaling as well. This would be like projection from 4326 to a vector tile.
            mapnik::geometry::scale_rounding_strategy ss(16);
            using sg_type =
              strategy_group<mapnik::proj_strategy, mapnik::view_strategy, mapnik::geometry::scale_rounding_strategy>;
            sg_type sg(ps, vs, ss);
            geometry<double> p1(point<double>(-97.553098, 35.523105));
            point<std::int64_t> r1(938, 1615);
            geometry<std::int64_t> p2 = transform<std::int64_t>(p1, sg);
            REQUIRE(p2.is<point<std::int64_t>>());
            point<std::int64_t> p3 = mapnik::util::get<point<std::int64_t>>(p2);
            assert_g_equal(r1, p3);
        }
        {
            // Test the entire process in reverse! This would be like converting a vector tile coordinate to 4326.
            mapnik::geometry::scale_strategy ss(1.0 / 16.0);
            using sg_type =
              strategy_group_first<mapnik::geometry::scale_strategy, mapnik::unview_strategy, mapnik::proj_strategy>;
            sg_type sg(ss, uvs, ps_rev);
            geometry<std::int64_t> p1(point<std::int64_t>(938, 1615));
            point<double> r1(-97.5586, 35.5322);
            geometry<double> p2 = transform<double>(p1, sg);
            REQUIRE(p2.is<point<double>>());
            point<double> p3 = mapnik::util::get<point<double>>(p2);
            assert_g_equal(r1, p3);
        }
        {
            // Test with scaling + offset as well. This would be like projection from 4326 to a vector tile.
            mapnik::geometry::scale_rounding_strategy ss(16, 20);
            using sg_type =
              strategy_group<mapnik::proj_strategy, mapnik::view_strategy, mapnik::geometry::scale_rounding_strategy>;
            sg_type sg(ps, vs, ss);
            geometry<double> p1(point<double>(-97.553098, 35.523105));
            point<std::int64_t> r1(958, 1635);
            geometry<std::int64_t> p2 = transform<std::int64_t>(p1, sg);
            REQUIRE(p2.is<point<std::int64_t>>());
            point<std::int64_t> p3 = mapnik::util::get<point<std::int64_t>>(p2);
            assert_g_equal(r1, p3);
        }
        {
            // Test the entire scaling plus offset in reverse process in reverse! This would be like converting a vector
            // tile coordinate to 4326.
            mapnik::geometry::scale_strategy ss(1.0 / 16.0, -20.0 / 16.0);
            using sg_type =
              strategy_group_first<mapnik::geometry::scale_strategy, mapnik::unview_strategy, mapnik::proj_strategy>;
            sg_type sg(ss, uvs, ps_rev);
            geometry<std::int64_t> p1(point<std::int64_t>(958, 1635));
            point<double> r1(-97.5586, 35.5322);
            geometry<double> p2 = transform<double>(p1, sg);
            REQUIRE(p2.is<point<double>>());
            point<double> p3 = mapnik::util::get<point<double>>(p2);
            assert_g_equal(r1, p3);
        }

    } // END SECTION

    SECTION("scaling strategies - double to double")
    {
        using namespace mapnik::geometry;

        {
            scale_strategy ss(10.0);
            point<double> p(-90.3, 35.5);
            point<double> r(-903.0, 355.0);
            point<double> o = transform<double>(p, ss);
            assert_g_equal(r, o);
        }
        {
            scale_strategy ss(0.5, -2.0);
            point<double> p(-90.3, 35.5);
            point<double> r(-47.15, 15.75);
            point<double> o = transform<double>(p, ss);
            assert_g_equal(r, o);
        }
        {
            scale_rounding_strategy ss(0.5, -2.0);
            point<double> p(-90.3, 35.5);
            point<double> r(-47.0, 16.0);
            point<double> o = transform<double>(p, ss);
            assert_g_equal(r, o);
        }

    } // END SECTION

    SECTION("scaling strategies - double to int64")
    {
        using namespace mapnik::geometry;

        {
            scale_strategy ss(10.0);
            point<double> p(-90.31, 35.58);
            point<std::int64_t> r(-903, 355);
            point<std::int64_t> o = transform<std::int64_t>(p, ss);
            assert_g_equal(r, o);
        }
        {
            scale_strategy ss(0.5, -2.0);
            point<double> p(-90.3, 35.5);
            point<std::int64_t> r(-47, 15);
            point<std::int64_t> o = transform<std::int64_t>(p, ss);
            assert_g_equal(r, o);
        }
        {
            scale_rounding_strategy ss(0.5, -2.0);
            point<double> p(-90.3, 35.5);
            point<std::int64_t> r(-47, 16);
            point<std::int64_t> o = transform<std::int64_t>(p, ss);
            assert_g_equal(r, o);
        }
    } // END SECTION
} // END TEST CASE