| // 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; |
| } |
| |
| //] |