// 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) //[area //` Calculate the area of a polygon #include <iostream> #include <boost/geometry.hpp> #include <boost/geometry/geometries/point_xy.hpp> #include <boost/geometry/geometries/polygon.hpp> namespace bg = boost::geometry; /*< Convenient namespace alias >*/ int main() { // Calculate the area of a cartesian polygon bg::model::polygon<bg::model::d2::point_xy<double> > poly; bg::read_wkt("POLYGON((0 0,0 7,4 2,2 0,0 0))", poly); double area = bg::area(poly); std::cout << "Area: " << area << std::endl; // Calculate the area of a spherical equatorial polygon bg::model::polygon<bg::model::point<float, 2, bg::cs::spherical_equatorial<bg::degree> > > sph_poly; bg::read_wkt("POLYGON((0 0,0 45,45 0,0 0))", sph_poly); area = bg::area(sph_poly); std::cout << "Area: " << area << std::endl; return 0; } //] //[area_output /*` Output: [pre Area: 16 Area: 0.339837 ] */ //]