1 // Boost.Geometry Index
2 //
3 // Quickbook Examples
4 //
5 // Copyright (c) 2011-2013 Adam Wulkiewicz, Lodz, Poland.
6 //
7 // Use, modification and distribution is subject to the Boost Software License,
8 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
9 // http://www.boost.org/LICENSE_1_0.txt)
10
11 //[rtree_polygons_vector
12
13 #include <boost/geometry.hpp>
14 #include <boost/geometry/geometries/point.hpp>
15 #include <boost/geometry/geometries/box.hpp>
16 #include <boost/geometry/geometries/polygon.hpp>
17
18 #include <boost/geometry/index/rtree.hpp>
19
20 #include <cmath>
21 #include <vector>
22 #include <iostream>
23 #include <boost/foreach.hpp>
24
25 namespace bg = boost::geometry;
26 namespace bgi = boost::geometry::index;
27
main()28 int main()
29 {
30 typedef bg::model::point<float, 2, bg::cs::cartesian> point;
31 typedef bg::model::box<point> box;
32 typedef bg::model::polygon<point, false, false> polygon; // ccw, open polygon
33 typedef std::pair<box, unsigned> value;
34
35 // polygons
36 std::vector<polygon> polygons;
37
38 // create some polygons
39 for ( unsigned i = 0 ; i < 10 ; ++i )
40 {
41 // create a polygon
42 polygon p;
43 for ( float a = 0 ; a < 6.28316f ; a += 1.04720f )
44 {
45 float x = i + int(10*::cos(a))*0.1f;
46 float y = i + int(10*::sin(a))*0.1f;
47 p.outer().push_back(point(x, y));
48 }
49
50 // add polygon
51 polygons.push_back(p);
52 }
53
54 // display polygons
55 std::cout << "generated polygons:" << std::endl;
56 BOOST_FOREACH(polygon const& p, polygons)
57 std::cout << bg::wkt<polygon>(p) << std::endl;
58
59 // create the rtree using default constructor
60 bgi::rtree< value, bgi::rstar<16, 4> > rtree;
61
62 // fill the spatial index
63 for ( unsigned i = 0 ; i < polygons.size() ; ++i )
64 {
65 // calculate polygon bounding box
66 box b = bg::return_envelope<box>(polygons[i]);
67 // insert new value
68 rtree.insert(std::make_pair(b, i));
69 }
70
71 // find values intersecting some area defined by a box
72 box query_box(point(0, 0), point(5, 5));
73 std::vector<value> result_s;
74 rtree.query(bgi::intersects(query_box), std::back_inserter(result_s));
75
76 // find 5 nearest values to a point
77 std::vector<value> result_n;
78 rtree.query(bgi::nearest(point(0, 0), 5), std::back_inserter(result_n));
79
80 // note: in Boost.Geometry the WKT representation of a box is polygon
81
82 // note: the values store the bounding boxes of polygons
83 // the polygons aren't used for querying but are printed
84
85 // display results
86 std::cout << "spatial query box:" << std::endl;
87 std::cout << bg::wkt<box>(query_box) << std::endl;
88 std::cout << "spatial query result:" << std::endl;
89 BOOST_FOREACH(value const& v, result_s)
90 std::cout << bg::wkt<polygon>(polygons[v.second]) << std::endl;
91
92 std::cout << "knn query point:" << std::endl;
93 std::cout << bg::wkt<point>(point(0, 0)) << std::endl;
94 std::cout << "knn query result:" << std::endl;
95 BOOST_FOREACH(value const& v, result_n)
96 std::cout << bg::wkt<polygon>(polygons[v.second]) << std::endl;
97
98 return 0;
99 }
100
101 //]
102