// Boost.Geometry (aka GGL, Generic Geometry Library) // QuickBook Example // Copyright (c) 2011-2012 Barend Gehrels, Amsterdam, the Netherlands. // 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) //[clear //` Shows how to clear a ring or polygon #include <iostream> #include <boost/geometry.hpp> #include <boost/geometry/geometries/polygon.hpp> #include <boost/geometry/geometries/ring.hpp> #include <boost/geometry/geometries/adapted/boost_tuple.hpp> BOOST_GEOMETRY_REGISTER_BOOST_TUPLE_CS(cs::cartesian) #include <boost/assign.hpp> int main() { using boost::assign::tuple_list_of; typedef boost::tuple<float, float> point; typedef boost::geometry::model::polygon<point> polygon; typedef boost::geometry::model::ring<point> ring; polygon poly; // Fill the polygon (using its own methods + Boost.Assign) poly.outer() = tuple_list_of(0, 0)(0, 9)(10, 10)(0, 0); poly.inners().push_back(tuple_list_of(1, 2)(4, 6)(2, 8)(1, 2)); std::cout << boost::geometry::dsv(poly) << std::endl; boost::geometry::clear(poly); std::cout << boost::geometry::dsv(poly) << std::endl; // Create a ring using Boost.Assign ring r = tuple_list_of(0, 0)(0, 9)(8, 8)(0, 0); std::cout << boost::geometry::dsv(r) << std::endl; boost::geometry::clear(r); std::cout << boost::geometry::dsv(r) << std::endl; return 0; } //] //[clear_output /*` Output: [pre (((0, 0), (0, 10), (11, 11), (0, 0)), ((0, 0), (0, 10), (11, 11), (0, 0))) (()) ((0, 0), (0, 9), (8, 8), (0, 0)) () ] */ //]