make (2 coordinate values)

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##### make (2 coordinate values)

Construct a geometry.

###### Synopsis

    template<typename Geometry, typename Type>
    Geometry make(Type const & c1, Type const & c2)

###### Parameters

Type | Concept | Name | Description
--- | --- | --- | ---
Geometry | Any type fulfilling a Geometry Concept | - | Must be specified
Type const & | numerical type (int, double, ttmath, ...) to specify the coordinates | c1 | First coordinate (usually x-coordinate)
Type const & | numerical type (int, double, ttmath, ...) to specify the coordinates | c2 | Second coordinate (usually y-coordinate)

###### Returns

The constructed geometry, here: a 2D point

###### Header

Either

`#include <boost/geometry.hpp>`

Or

`#include <boost/geometry/algorithms/make.hpp>`

###### Example

Shows the usage of make as a generic constructor for different point types

    #include <iostream>

    #include <boost/geometry.hpp>
    #include <boost/geometry/geometries/point_xy.hpp>
    #include <boost/geometry/geometries/register/point.hpp>
    #include <boost/geometry/geometries/adapted/boost_tuple.hpp>
    #include <boost/geometry/geometries/adapted/boost_polygon/point.hpp>

    BOOST_GEOMETRY_REGISTER_BOOST_TUPLE_CS(cs::cartesian)

    struct mypoint { float _x, _y; };

    BOOST_GEOMETRY_REGISTER_POINT_2D(mypoint, float, cs::cartesian, _x, _y)

    template <typename Point>
    void construct_and_display()
    {
        using boost::geometry::make;
        using boost::geometry::get;

        Point p = make<Point>(1, 2);

        std::cout << "x=" << get<0>(p) << " y=" << get<1>(p)
            << " (" << typeid(Point).name() << ")"
            << std::endl;
    }

    int main()
    {
        construct_and_display<boost::geometry::model::d2::point_xy<double> >();
        construct_and_display<boost::geometry::model::d2::point_xy<int> >();
        construct_and_display<boost::tuple<double, double> >();
        construct_and_display<boost::polygon::point_data<int> >();
        construct_and_display<mypoint>();
        return 0;
    }

Output (compiled using gcc):

    x=1 y=2 (N5boost8geometry5model2d28point_xyIdNS0_2cs9cartesianEEE)
    x=1 y=2 (N5boost8geometry5model2d28point_xyIiNS0_2cs9cartesianEEE)
    x=1 y=2 (N5boost6tuples5tupleIddNS0_9null_typeES2_S2_S2_S2_S2_S2_S2_EE)
    x=1 y=2 (N5boost7polygon10point_dataIiEE)
    x=1 y=2 (7mypoint)

###### See also

- assign