libs/geometry/doc/src/examples/algorithms/append.cpp

// Boost.Geometry (aka GGL, Generic Geometry Library)
// QuickBook Example

// Copyright (c) 2011 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)

//[append
//` Shows usage of Boost.Geometry's append to append a point or a range to a polygon

#include <iostream>

#include <boost/assign.hpp>

#include <boost/geometry.hpp>
#include <boost/geometry/geometries/polygon.hpp>
#include <boost/geometry/geometries/adapted/boost_tuple.hpp>

BOOST_GEOMETRY_REGISTER_BOOST_TUPLE_CS(cs::cartesian)

int main()
{
    using boost::assign::tuple_list_of;
    using boost::make_tuple;
    using boost::geometry::append;

    typedef boost::geometry::model::polygon<boost::tuple<int, int> > polygon;

    polygon poly;

    // Append a range
    append(poly, tuple_list_of(0, 0)(0, 10)(11, 11)(10, 0)); /*< tuple_list_of delivers a range and can therefore be used in boost::geometry::append >*/
    // Append a point (in this case the closing point
    append(poly, make_tuple(0, 0));

    // Create an interior ring (append does not do this automatically)
    boost::geometry::interior_rings(poly).resize(1);

    // Append a range to the interior ring
    append(poly, tuple_list_of(2, 2)(2, 5)(6, 6)(5, 2), 0);
    // Append a point to the first interior ring
    append(poly, make_tuple(2, 2), 0);

    std::cout << boost::geometry::dsv(poly) << std::endl;

    return 0;
}

//]


//[append_output
/*`
Output:
[pre
(((0, 0), (0, 10), (11, 11), (10, 0), (0, 0)), ((2, 2), (2, 5), (6, 6), (5, 2), (2, 2)))
]
*/
//]