// Boost.Geometry // QuickBook Example // Copyright (c) 2011-2012 Barend Gehrels, Amsterdam, the Netherlands. // Copyright (c) 2015 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) //[multi_polygon //` Declaration and use of the Boost.Geometry model::multi_polygon, modelling the MultiPolygon Concept #include #include #include namespace bg = boost::geometry; int main() { typedef bg::model::point point_t; typedef bg::model::polygon polygon_t; /*< Default parameters, clockwise, closed polygon. >*/ typedef bg::model::multi_polygon mpolygon_t; /*< Clockwise, closed multi_polygon. >*/ mpolygon_t mpoly1; /*< Default-construct a multi_polygon. >*/ #if !defined(BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX) \ && !defined(BOOST_NO_CXX11_HDR_INITIALIZER_LIST) mpolygon_t mpoly2{{{{0.0, 0.0}, {0.0, 5.0}, {5.0, 5.0}, {5.0, 0.0}, {0.0, 0.0}}, {{1.0, 1.0}, {4.0, 1.0}, {4.0, 4.0}, {1.0, 4.0}, {1.0, 1.0}}}, {{{5.0, 5.0}, {5.0, 6.0}, {6.0, 6.0}, {6.0, 5.0}, {5.0, 5.0}}}}; /*< Construct a multi_polygon containing two polygons, using C++11 unified initialization syntax. >*/ #endif mpoly1.resize(2); /*< Resize a multi_polygon, store two polygons. >*/ bg::append(mpoly1[0].outer(), point_t(0.0, 0.0)); /*< Append point to the exterior ring of the first polygon. >*/ bg::append(mpoly1[0].outer(), point_t(0.0, 5.0)); bg::append(mpoly1[0].outer(), point_t(5.0, 5.0)); bg::append(mpoly1[0].outer(), point_t(5.0, 0.0)); bg::append(mpoly1[0].outer(), point_t(0.0, 0.0)); mpoly1[0].inners().resize(1); /*< Resize a container of interior rings of the first polygon. >*/ bg::append(mpoly1[0].inners()[0], point_t(1.0, 1.0)); /*< Append point to the interior ring of the first polygon. >*/ bg::append(mpoly1[0].inners()[0], point_t(4.0, 1.0)); bg::append(mpoly1[0].inners()[0], point_t(4.0, 4.0)); bg::append(mpoly1[0].inners()[0], point_t(1.0, 4.0)); bg::append(mpoly1[0].inners()[0], point_t(1.0, 1.0)); bg::append(mpoly1[1].outer(), point_t(5.0, 5.0)); /*< Append point to the exterior ring of the second polygon. >*/ bg::append(mpoly1[1].outer(), point_t(5.0, 6.0)); bg::append(mpoly1[1].outer(), point_t(6.0, 6.0)); bg::append(mpoly1[1].outer(), point_t(6.0, 5.0)); bg::append(mpoly1[1].outer(), point_t(5.0, 5.0)); double a = bg::area(mpoly1); std::cout << a << std::endl; return 0; } //] //[multi_polygon_output /*` Output: [pre 17 ] */ //]