Boost C++ Libraries

Let the buffer algorithm create buffers with same distances.

Synopsis

template<typename NumericType>
class strategy::buffer::distance_symmetric
{
  // ...
};

Template parameter(s)

Constructor(s)

distance_symmetric(NumericType const & distance)

Header

#include <boost/geometry/strategies/agnostic/buffer_distance_symmetric.hpp>

Example

Shows how the distance_symmetric strategy can be used as a DistanceStrategy to create symmetric buffers

#include <boost/geometry.hpp>
#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/geometries/geometries.hpp>


int main()
{
    using point = boost::geometry::model::d2::point_xy<double>;
    using linestring = boost::geometry::model::linestring<point>;
    using polygon = boost::geometry::model::polygon<point>;

    // Declare the symmetric distance strategy
    boost::geometry::strategy::buffer::distance_symmetric<double> distance_strategy(0.5);

    // Declare other strategies
    boost::geometry::strategy::buffer::side_straight side_strategy;
    boost::geometry::strategy::buffer::join_round join_strategy;
    boost::geometry::strategy::buffer::end_round end_strategy;
    boost::geometry::strategy::buffer::point_circle point_strategy;

    // Declare/fill a multi linestring
    boost::geometry::model::multi_linestring<linestring> ml;
    boost::geometry::read_wkt("MULTILINESTRING((3 5,5 10,7 5),(7 7,11 10,15 7,19 10))", ml);

    // Create the buffered geometry with left/right the same distance
    boost::geometry::model::multi_polygon<polygon> result;
    boost::geometry::buffer(ml, result,
                distance_strategy, side_strategy,
                join_strategy, end_strategy, point_strategy);


    return 0;
}

Output

See also