strategy::buffer::distance_asymmetric

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#### strategy::buffer::distance_asymmetric

Let the buffer for linestrings be asymmetric.

###### Synopsis

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

###### Template parameter(s)

Parameter | Description
--- | ---
typename NumericType | numerical type (int, double, ttmath, ...)

###### Constructor(s)

Function | Description | Parameters
--- | --- | ---

    distance_asymmetric(NumericType const & left, NumericType const & right)

Constructs the strategy, two distances must be specified.

NumericType const &: left: The distance (or radius) of the buffer on the left side

NumericType const &: right: The distance on the right side

###### Header

`#include <boost/geometry/strategies/agnostic/buffer_distance_asymmetric.hpp>`

###### Example

Shows how the distance_asymmetric strategy can be used as a DistanceStrategy to create asymmetric buffers

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

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

        // Declare the asymmetric distance strategy
        boost::geometry::strategy::buffer::distance_asymmetric<double> distance_strategy(1.0, 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 a different 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

- buffer (with strategies)
- distance_symmetric