relate (with strategy)

Checks relation between a pair of geometries defined by a mask.

Synopsis

template<typename Geometry1, typename Geometry2, typename Mask, typename Strategy>
bool relate(Geometry1 const & geometry1, Geometry2 const & geometry2, Mask const & mask,
            Strategy const & strategy)

Parameters

Type	Concept	Name	Description
Geometry1 const &	Any type fulfilling a Geometry Concept	geometry1	A model of the specified concept
Geometry2 const &	Any type fulfilling a Geometry Concept	geometry2	A model of the specified concept
Mask const &	An intersection model Mask type.	mask	An intersection model mask object.
Strategy const &	Any type fulfilling a Relate Strategy Concept	strategy	The strategy which will be used for relate calculations

Returns

true if the relation is compatible with the mask, false otherwise.

Header

Either

#include <boost/geometry.hpp>

#include <boost/geometry/algorithms/relate.hpp>

Conformance

The function relate implements function Relate from the OGC Simple Feature Specification.

Example

Shows how to detect if a point is inside a polygon, or not

#include <iostream>

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


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

    polygon_type poly;
    boost::geometry::read_wkt(
        "POLYGON((2 1.3,2.4 1.7,2.8 1.8,3.4 1.2,3.7 1.6,3.4 2,4.1 3,5.3 2.6,5.4 1.2,4.9 0.8,2.9 0.7,2 1.3)"
            "(4.0 2.0, 4.2 1.4, 4.8 1.9, 4.4 2.2, 4.0 2.0))", poly);

    point_type p(4, 1);

    boost::geometry::de9im::mask mask("T*F**F***"); // within
    bool check = boost::geometry::relate(p, poly, mask);

    std::cout << "relate: " << (check ? "yes" : "no") << std::endl;

    return 0;
}

Output:

relate: yes

Boost C++ Libraries