// Boost.Geometry Index // // Quickbook Examples // // Copyright (c) 2011-2013 Adam Wulkiewicz, Lodz, Poland. // // Use, modification and distribution is subject to the Boost Software License, // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) //[rtree_variants_map #include <boost/geometry.hpp> #include <boost/geometry/geometries/point.hpp> #include <boost/geometry/geometries/box.hpp> #include <boost/geometry/geometries/polygon.hpp> #include <boost/geometry/geometries/ring.hpp> #include <boost/geometry/geometries/linestring.hpp> #include <boost/geometry/index/rtree.hpp> #include <cmath> #include <vector> #include <map> #include <iostream> #include <boost/foreach.hpp> #include <boost/variant.hpp> namespace bg = boost::geometry; namespace bgi = boost::geometry::index; typedef bg::model::point<float, 2, bg::cs::cartesian> point; typedef bg::model::box<point> box; typedef bg::model::polygon<point, false, false> polygon; // ccw, open polygon typedef bg::model::ring<point, false, false> ring; // ccw, open ring typedef bg::model::linestring<point> linestring; typedef boost::variant<polygon, ring, linestring> geometry; typedef std::map<unsigned, geometry> map; typedef std::pair<box, map::iterator> value; template <class Container> void fill(unsigned i, Container & container) { for ( float a = 0 ; a < 6.28316f ; a += 1.04720f ) { float x = i + int(10*::cos(a))*0.1f; float y = i + int(10*::sin(a))*0.1f; container.push_back(point(x, y)); } } struct print_visitor : public boost::static_visitor<> { void operator()(polygon const& g) const { std::cout << bg::wkt<polygon>(g) << std::endl; } void operator()(ring const& g) const { std::cout << bg::wkt<ring>(g) << std::endl; } void operator()(linestring const& g) const { std::cout << bg::wkt<linestring>(g) << std::endl; } }; struct envelope_visitor : public boost::static_visitor<box> { box operator()(polygon const& g) const { return bg::return_envelope<box>(g); } box operator()(ring const& g) const { return bg::return_envelope<box>(g); } box operator()(linestring const& g) const { return bg::return_envelope<box>(g); } }; int main() { // geometries container map geometries; // create some geometries for ( unsigned i = 0 ; i < 10 ; ++i ) { unsigned c = rand() % 3; if ( 0 == c ) { // create polygon polygon p; fill(i, p.outer()); geometries.insert(std::make_pair(i, geometry(p))); } else if ( 1 == c ) { // create ring ring r; fill(i, r); geometries.insert(std::make_pair(i, geometry(r))); } else if ( 2 == c ) { // create linestring linestring l; fill(i, l); geometries.insert(std::make_pair(i, geometry(l))); } } // display geometries std::cout << "generated geometries:" << std::endl; BOOST_FOREACH(map::value_type const& p, geometries) boost::apply_visitor(print_visitor(), p.second); // create the rtree using default constructor bgi::rtree< value, bgi::quadratic<16, 4> > rtree; // fill the spatial index for ( map::iterator it = geometries.begin() ; it != geometries.end() ; ++it ) { // calculate polygon bounding box box b = boost::apply_visitor(envelope_visitor(), it->second); // insert new value rtree.insert(std::make_pair(b, it)); } // find values intersecting some area defined by a box box query_box(point(0, 0), point(5, 5)); std::vector<value> result_s; rtree.query(bgi::intersects(query_box), std::back_inserter(result_s)); // find 5 nearest values to a point std::vector<value> result_n; rtree.query(bgi::nearest(point(0, 0), 5), std::back_inserter(result_n)); // note: in Boost.Geometry the WKT representation of a box is polygon // note: the values store the bounding boxes of geometries // the geometries aren't used for querying but are printed // display results std::cout << "spatial query box:" << std::endl; std::cout << bg::wkt<box>(query_box) << std::endl; std::cout << "spatial query result:" << std::endl; BOOST_FOREACH(value const& v, result_s) boost::apply_visitor(print_visitor(), v.second->second); std::cout << "knn query point:" << std::endl; std::cout << bg::wkt<point>(point(0, 0)) << std::endl; std::cout << "knn query result:" << std::endl; BOOST_FOREACH(value const& v, result_n) boost::apply_visitor(print_visitor(), v.second->second); return 0; } //]