ceph/src/boost/libs/geometry/doc/index/src/examples/rtree/quick_start.cpp

   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_quickstart
  12
  13 //[rtree_quickstart_include
  14
  15 #include <boost/geometry.hpp>
  16 #include <boost/geometry/geometries/point.hpp>
  17 #include <boost/geometry/geometries/box.hpp>
  18
  19 #include <boost/geometry/index/rtree.hpp>
  20
  21 // to store queries results
  22 #include <vector>
  23
  24 // just for output
  25 #include <iostream>
  26 #include <boost/foreach.hpp>
  27
  28 namespace bg = boost::geometry;
  29 namespace bgi = boost::geometry::index;
  30 //]
  31
  32 int main()
  33 {
  34     //[rtree_quickstart_valuetype
  35     typedef bg::model::point<float, 2, bg::cs::cartesian> point;
  36     typedef bg::model::box<point> box;
  37     typedef std::pair<box, unsigned> value;
  38     //]
  39
  40     //[rtree_quickstart_create
  41     // create the rtree using default constructor
  42     bgi::rtree< value, bgi::quadratic<16> > rtree;
  43     //]
  44
  45     //[rtree_quickstart_insert
  46     // create some values
  47     for ( unsigned i = 0 ; i < 10 ; ++i )
  48     {
  49         // create a box
  50         box b(point(i + 0.0f, i + 0.0f), point(i + 0.5f, i + 0.5f));
  51         // insert new value
  52         rtree.insert(std::make_pair(b, i));
  53     }
  54     //]
  55
  56     //[rtree_quickstart_spatial_query
  57     // find values intersecting some area defined by a box
  58     box query_box(point(0, 0), point(5, 5));
  59     std::vector<value> result_s;
  60     rtree.query(bgi::intersects(query_box), std::back_inserter(result_s));
  61     //]
  62
  63     //[rtree_quickstart_nearest_query
  64     // find 5 nearest values to a point
  65     std::vector<value> result_n;
  66     rtree.query(bgi::nearest(point(0, 0), 5), std::back_inserter(result_n));
  67     //]
  68
  69     // note: in Boost.Geometry WKT representation of a box is polygon
  70
  71     //[rtree_quickstart_output
  72     // display results
  73     std::cout << "spatial query box:" << std::endl;
  74     std::cout << bg::wkt<box>(query_box) << std::endl;
  75     std::cout << "spatial query result:" << std::endl;
  76     BOOST_FOREACH(value const& v, result_s)
  77         std::cout << bg::wkt<box>(v.first) << " - " << v.second << std::endl;
  78
  79     std::cout << "knn query point:" << std::endl;
  80     std::cout << bg::wkt<point>(point(0, 0)) << std::endl;
  81     std::cout << "knn query result:" << std::endl;
  82     BOOST_FOREACH(value const& v, result_n)
  83         std::cout << bg::wkt<box>(v.first) << " - " << v.second << std::endl;
  84     //]
  85
  86     return 0;
  87 }
  88
  89 //]