Boost C++ Libraries

Boost.Range strided range adaptor is adapted to Boost.Geometry

Description

Boost.Range strided range adaptor makes a strided range (usually begin a linestring or ring) such that traversal is performed in steps of n.

Model of

The Boost.Range strided range adaptor takes over the model of the original geometry, which might be:

Header

#include <boost/geometry/geometries/adapted/boost_range/strided.hpp>

The standard header boost/geometry.hpp does not include this header.

Example

Shows how to use a Boost.Geometry ring, strided by Boost.Range adaptor

#include <iostream>

#include <boost/geometry.hpp>
#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/geometries/ring.hpp>
#include <boost/geometry/geometries/adapted/boost_range/strided.hpp>

#include <boost/assign.hpp> 


int main()
{
    using namespace boost::assign;
    using boost::adaptors::strided;

    typedef boost::geometry::model::d2::point_xy<int> xy;
    boost::geometry::model::ring<xy> ring;
    ring += xy(0, 0);
    ring += xy(0, 1);
    ring += xy(0, 2);
    ring += xy(1, 2);
    ring += xy(2, 2);
    ring += xy(2, 0);

    boost::geometry::correct(ring);

    std::cout
        << "Normal : " << boost::geometry::dsv(ring) << std::endl
        << "Strided: " << boost::geometry::dsv(ring | strided(2)) << std::endl;

    return 0;
}

Output:

Normal : ((0, 0), (0, 1), (0, 2), (1, 2), (2, 2), (2, 0), (0, 0))
Strided: ((0, 0), (0, 2), (2, 2), (0, 0))