/Src/Dependencies/Boost/libs/geometry/test/algorithms/test_convex_hull.hpp

  1// Boost.Geometry (aka GGL, Generic Geometry Library) 
  2// Unit Test
  3
  4// Copyright (c) 2007-2011 Barend Gehrels, Amsterdam, the Netherlands.
  5// Use, modification and distribution is subject to the Boost Software License,
  6// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  7// http://www.boost.org/LICENSE_1_0.txt)
  8
  9#ifndef BOOST_GEOMETRY_TEST_CONVEX_HULL_HPP
 10#define BOOST_GEOMETRY_TEST_CONVEX_HULL_HPP
 11
 12#include <geometry_test_common.hpp>
 13
 14#include <boost/geometry/algorithms/convex_hull.hpp>
 15#include <boost/geometry/algorithms/area.hpp>
 16#include <boost/geometry/algorithms/num_points.hpp>
 17
 18#include <boost/geometry/strategies/strategies.hpp>
 19
 20#include <boost/geometry/domains/gis/io/wkt/read_wkt.hpp>
 21#include <boost/geometry/domains/gis/io/wkt/write_wkt.hpp>
 22
 23#include <boost/geometry/geometries/polygon.hpp>
 24
 25
 26template <typename Geometry, typename Hull>
 27void test_convex_hull(Geometry const& geometry, Hull const& hull,
 28                      std::size_t size_original, std::size_t size_hull,
 29                      double expected_area, bool reverse)
 30{
 31
 32    std::size_t n = bg::num_points(hull);
 33
 34    BOOST_CHECK_MESSAGE(n == size_hull,
 35        "convex hull: " << bg::wkt(geometry)
 36        << " -> " << bg::wkt(hull)
 37        << " type "
 38        << (typeid(typename bg::coordinate_type<Hull>::type).name())
 39        << " -> Expected: " << size_hull
 40        << " detected: " << n);
 41
 42
 43    BOOST_CHECK(bg::num_points(geometry) == size_original);
 44
 45    typename bg::default_area_result<Geometry>::type ah = bg::area(hull);
 46    if (reverse)
 47    {
 48        ah = -ah;
 49    }
 50
 51//std::cout << "Area: " << bg::area(geometry) << std::endl;
 52//std::cout << bg::wkt(hull) << std::endl;
 53
 54    BOOST_CHECK_CLOSE(ah, expected_area, 0.001);
 55}
 56
 57template <typename Geometry, bool Clockwise>
 58void test_geometry_order(std::string const& wkt,
 59                      std::size_t size_original, std::size_t size_hull,
 60                      double expected_area)
 61{
 62    Geometry geometry;
 63    bg::read_wkt(wkt, geometry);
 64
 65    bg::model::polygon
 66        <
 67            typename bg::point_type<Geometry>::type,
 68            Clockwise
 69        > hull;
 70
 71    // Test version with output iterator
 72    bg::detail::convex_hull::convex_hull_insert(geometry, std::back_inserter(hull.outer()));
 73    test_convex_hull(geometry, hull,
 74        size_original, size_hull, expected_area, ! Clockwise);
 75
 76    // Test version with ring as output
 77    bg::clear(hull);
 78    bg::convex_hull(geometry, hull.outer());
 79    test_convex_hull(geometry, hull, size_original, size_hull, expected_area, false);
 80
 81    // Test version with polygon as output
 82    bg::clear(hull);
 83    bg::convex_hull(geometry, hull);
 84    test_convex_hull(geometry, hull, size_original, size_hull, expected_area, false);
 85
 86    // Test version with strategy
 87    bg::clear(hull);
 88    bg::strategy::convex_hull::graham_andrew
 89        <
 90            Geometry,
 91            typename bg::point_type<Geometry>::type
 92        > graham;
 93    bg::convex_hull(geometry, hull.outer(), graham);
 94    test_convex_hull(geometry, hull, size_original, size_hull, expected_area, false);
 95
 96    // Test version with output iterator and strategy
 97    bg::clear(hull);
 98    bg::detail::convex_hull::convex_hull_insert(geometry, std::back_inserter(hull.outer()), graham);
 99    test_convex_hull(geometry, hull, size_original, size_hull, expected_area, ! Clockwise);
100}
101
102template <typename Geometry>
103void test_geometry(std::string const& wkt,
104                      std::size_t size_original, std::size_t size_hull,
105                      double expected_area)
106{
107    test_geometry_order<Geometry, true>(wkt, size_original, size_hull, expected_area);
108    test_geometry_order<Geometry, false>(wkt, size_original, size_hull, expected_area);
109}
110
111
112#endif