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48 lines
1.2 KiB
C++
48 lines
1.2 KiB
C++
// Boost.Geometry (aka GGL, Generic Geometry Library)
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//
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// Copyright Barend Gehrels 2011, Geodan, Amsterdam, the Netherlands
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// Use, modification and distribution is subject to the Boost Software License,
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// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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//
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// Quickbook Example
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//[area
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//` Calculate the area of a polygon
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#include <iostream>
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#include <boost/geometry/geometry.hpp>
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#include <boost/geometry/domains/gis/io/wkt/wkt.hpp>
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namespace bg = boost::geometry; /*< Convenient namespace alias >*/
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int main()
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{
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// Calculate the area of a cartesian polygon
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bg::model::polygon<bg::model::d2::point_xy<double> > poly;
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bg::read_wkt("POLYGON((0 0,0 7,4 2,2 0,0 0))", poly);
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double area = bg::area(poly);
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std::cout << "Area: " << area << std::endl;
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// Calculate the area of a spherical polygon
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bg::model::polygon<bg::model::point<float, 2, bg::cs::spherical<bg::degree> > > sph_poly;
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bg::read_wkt("POLYGON((0 0,0 45,45 0,0 0))", sph_poly);
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area = bg::area(sph_poly);
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std::cout << "Area: " << area << std::endl;
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return 0;
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}
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//]
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//[area_output
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/*`
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Output:
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[pre
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Area: 16
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Area: 0.339837
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]
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*/
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//]
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