| // 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_value_index |
| |
| #include <boost/geometry.hpp> |
| #include <boost/geometry/geometries/point.hpp> |
| #include <boost/geometry/geometries/box.hpp> |
| |
| #include <boost/geometry/index/rtree.hpp> |
| |
| #include <cmath> |
| #include <vector> |
| #include <iostream> |
| #include <boost/foreach.hpp> |
| |
| namespace bg = boost::geometry; |
| namespace bgi = boost::geometry::index; |
| |
| template <typename Container> |
| class my_indexable |
| { |
| typedef typename Container::size_type size_t; |
| typedef typename Container::const_reference cref; |
| Container const& container; |
| |
| public: |
| typedef cref result_type; |
| explicit my_indexable(Container const& c) : container(c) {} |
| result_type operator()(size_t i) const { return container[i]; } |
| }; |
| |
| int main() |
| { |
| typedef bg::model::point<float, 2, bg::cs::cartesian> point; |
| typedef bg::model::box<point> box; |
| typedef std::vector<box>::size_type value; |
| typedef bgi::rstar<16, 4> parameters; |
| typedef my_indexable< std::vector<box> > indexable_getter; |
| |
| // boxes |
| std::vector<box> boxes; |
| |
| // create some boxes |
| for ( unsigned i = 0 ; i < 10 ; ++i ) |
| { |
| // add a box |
| boxes.push_back(box(point(i+0.0f, i+0.0f), point(i+0.5f, i+0.5f))); |
| } |
| |
| // display boxes |
| std::cout << "generated boxes:" << std::endl; |
| BOOST_FOREACH(box const& b, boxes) |
| std::cout << bg::wkt<box>(b) << std::endl; |
| |
| // create the rtree |
| parameters params; |
| indexable_getter ind(boxes); |
| bgi::rtree<value, parameters, indexable_getter> rtree(params, ind); |
| |
| // fill the spatial index |
| for ( size_t i = 0 ; i < boxes.size() ; ++i ) |
| rtree.insert(i); |
| |
| // 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 |
| |
| // 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 i, result_s) |
| std::cout << bg::wkt<box>(boxes[i]) << std::endl; |
| |
| 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 i, result_n) |
| std::cout << bg::wkt<box>(boxes[i]) << std::endl; |
| |
| return 0; |
| } |
| |
| //] |