libs/geometry/test/algorithms/buffer/buffer_with_strategies.cpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2 // Unit Test
   3
   4 // Copyright (c) 2015-2019 Barend Gehrels, Amsterdam, the Netherlands.
   5
   6 // Use, modification and distribution is subject to the Boost Software License,
   7 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   8 // http://www.boost.org/LICENSE_1_0.txt)
   9
  10 #include "geometry_test_common.hpp"
  11
  12 #include <boost/geometry/algorithms/buffer.hpp>
  13
  14 #include <boost/geometry/strategies/strategies.hpp>
  15
  16 #include <boost/geometry/geometries/geometries.hpp>
  17
  18 // For test
  19 #include <boost/geometry/algorithms/area.hpp>
  20 #include <boost/geometry/algorithms/correct.hpp>
  21 #include <boost/geometry/algorithms/num_points.hpp>
  22
  23
  24 // This unit test tests boost::geometry::buffer (overload with strategies)
  25 // More detailed tests are, per geometry type, available in buffer_<TYPE>.cpp
  26 // (testing boost::geometry::buffer_inserter)
  27
  28 // SVG's are not created (they are in detailed tests)
  29
  30 static std::string const polygon_simplex = "POLYGON ((0 0,1 5,6 1,0 0))";
  31 static std::string const polygon_empty = "POLYGON()";
  32 static std::string const multi_polygon_empty = "MULTIPOLYGON()";
  33 static std::string const multi_polygon_simplex
  34     = "MULTIPOLYGON(((0 1,2 5,5 3,0 1)),((1 1,5 2,5 0,1 1)))";
  35
  36
  37 template
  38 <
  39     typename Geometry,
  40     typename GeometryOut,
  41     typename JoinStrategy,
  42     typename EndStrategy,
  43     typename SideStrategy,
  44     typename PointStrategy,
  45     typename DistanceStrategy
  46 >
  47 void test_with_strategies(std::string const& caseid,
  48         std::string const& wkt,
  49         JoinStrategy const& join_strategy,
  50         EndStrategy const& end_strategy,
  51         SideStrategy const& side_strategy,
  52         PointStrategy const& point_strategy,
  53         DistanceStrategy const& distance_strategy,
  54         double expected_area,
  55         std::size_t expected_numpoints,
  56         double tolerance = 0.01)
  57 {
  58     namespace bg = boost::geometry;
  59     Geometry g;
  60     bg::read_wkt(wkt, g);
  61     bg::correct(g);
  62
  63     GeometryOut result;
  64
  65     bg::buffer(g, result,
  66                 distance_strategy, side_strategy,
  67                 join_strategy, end_strategy, point_strategy);
  68
  69     BOOST_CHECK_MESSAGE
  70         (
  71             bg::num_points(result) == expected_numpoints,
  72             "Buffer " << caseid
  73             << " numpoints expected: " << expected_numpoints
  74             << " detected: " << bg::num_points(result)
  75         );
  76
  77     double const area = bg::area(result);
  78     double const difference = area - expected_area;
  79
  80     BOOST_CHECK_MESSAGE
  81         (
  82             bg::math::abs(difference) < tolerance,
  83             "Buffer " << caseid
  84             << std::setprecision(12)
  85             << " area expected: " << expected_area
  86             << " detected: " << area
  87         );
  88 }
  89
  90
  91 template <bool Clockwise, typename Point>
  92 void test_all()
  93 {
  94     typedef bg::model::polygon<Point, Clockwise> polygon;
  95     typedef bg::model::multi_polygon<polygon> multi_polygon;
  96
  97     bg::strategy::buffer::join_round join(160);
  98     bg::strategy::buffer::end_round end(160);
  99     bg::strategy::buffer::point_circle circle(160);
 100     bg::strategy::buffer::side_straight side;
 101
 102     typedef bg::strategy::buffer::distance_symmetric
 103     <
 104         typename bg::coordinate_type<Point>::type
 105     > distance;
 106
 107     test_with_strategies<multi_polygon, multi_polygon>(
 108         "multi_polygon_empty", multi_polygon_empty,
 109         join, end, side, circle, distance(1.0),
 110         0.0, 0);
 111
 112
 113     // PostGIS: 34.2550669294223 216 (40 / qcircle)
 114     // SQL Server: 34.2550419903829 220 (default options)
 115     test_with_strategies<multi_polygon, multi_polygon>(
 116         "multi_polygon_simplex", multi_polygon_simplex,
 117         join, end, side, circle, distance(1.0),
 118         34.2551, 219);
 119
 120     test_with_strategies<polygon, multi_polygon>(
 121         "polygon_empty", polygon_empty,
 122         join, end, side, circle, distance(1.0),
 123         0.0, 0);
 124
 125     //
 126     // PostGIS: 35.2256914798762 164 (40 / qcircle)
 127     // SQL Server: 35.2252355201605 153 (default options)
 128     test_with_strategies<polygon, multi_polygon>(
 129         "polygon_simplex", polygon_simplex,
 130         join, end, side, circle, distance(1.0),
 131         35.2257, 166);
 132 }
 133
 134 int test_main(int, char* [])
 135 {
 136     BoostGeometryWriteTestConfiguration();
 137
 138     test_all<true, bg::model::point<default_test_type, 2, bg::cs::cartesian> >();
 139
 140     return 0;
 141 }