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

   1 // Boost.Geometry Index
   2 //
   3 // Quickbook Examples
   4 //
   5 // Copyright (c) 2011-2014 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_iterative_query
  12
  13 #include <boost/geometry.hpp>
  14 #include <boost/geometry/geometries/point.hpp>
  15 #include <boost/geometry/geometries/box.hpp>
  16
  17 #include <boost/geometry/index/rtree.hpp>
  18
  19 // just for output
  20 #include <iostream>
  21
  22 namespace bg = boost::geometry;
  23 namespace bgi = boost::geometry::index;
  24
  25 int main()
  26 {
  27     typedef bg::model::point<double, 2, bg::cs::cartesian> point;
  28     typedef point value;
  29     typedef bgi::rtree< value, bgi::linear<16> > rtree_t;
  30
  31     // create the rtree using default constructor
  32     rtree_t rtree;
  33
  34     // create some values
  35     for ( double f = 0 ; f < 10 ; f += 1 )
  36     {
  37         // insert new value
  38         rtree.insert(point(f, f));
  39     }
  40
  41     // query point
  42     point pt(5.1, 5.1);
  43
  44     // iterate over nearest Values
  45     for ( rtree_t::const_query_iterator
  46             it = rtree.qbegin(bgi::nearest(pt, 100)) ;
  47             it != rtree.qend() ;
  48             ++it )
  49     {
  50         double d = bg::distance(pt, *it);
  51
  52         std::cout << bg::wkt(*it) << ", distance= " << d << std::endl;
  53
  54         // break if the distance is too big
  55         if ( d > 2 )
  56         {
  57             std::cout << "break!" << std::endl;
  58             break;
  59         }
  60     }
  61
  62     return 0;
  63 }
  64
  65 //]