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#### strategy::buffer::join_round

Let the buffer create rounded corners.

###### Description

This strategy can be used as JoinStrategy for the buffer algorithm. It creates a rounded corners around each convex vertex. It can be applied for (multi)linestrings and (multi)polygons. This strategy is only applicable for Cartesian coordinate systems.

###### Synopsis

    class strategy::buffer::join_round
    {
      // ...
    };

###### Constructor(s)

Function | Description | Parameters
--- | --- | ---
    join_round(std::size_t points_per_circle = 90)
| Constructs the strategy. | std::size_t: points_per_circle: points which would be used for a full circle

###### Header

`#include <boost/geometry/strategies/cartesian/buffer_join_round.hpp>`

###### Example

Shows how the join_round strategy can be used as a JoinStrategy to create rounded corners

    #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::polygon<point> polygon;

        // Declare the join_round strategy with 72 points for a full circle
        boost::geometry::strategy::buffer::join_round join_strategy(72);

        // Declare other strategies
        boost::geometry::strategy::buffer::distance_symmetric<double> distance_strategy(1.0);
        boost::geometry::strategy::buffer::end_flat end_strategy;
        boost::geometry::strategy::buffer::side_straight side_strategy;
        boost::geometry::strategy::buffer::point_circle point_strategy;

        // Declare/fill a multi polygon
        boost::geometry::model::multi_polygon<polygon> mp;
        boost::geometry::read_wkt("MULTIPOLYGON(((5 5,7 8,9 5,5 5)),((8 7,8 10,11 10,11 7,8 7)))", mp);

        // Create the buffered geometry with rounded corners
        boost::geometry::model::multi_polygon<polygon> result;
        boost::geometry::buffer(mp, result,
                    distance_strategy, side_strategy,
                    join_strategy, end_strategy, point_strategy);

        return 0;
    }

###### Output

###### See also

- buffer (with strategies)
- join_miter