| Home | Libraries | People | FAQ | More

#### segment_view

Makes a segment behave like a linestring or a range.

###### Description

Adapts a segment to the Boost.Range concept, enabling the user to iterate the two segment points. The segment_view is registered as a LineString Concept

###### Model of

LineString Concept

###### Synopsis

    template<typename Segment>
    struct segment_view
          : public detail::points_view< geometry::point_type< Segment >::type, 2 >
    {
      // ...
    };

###### Template parameter(s)

Parameter | Description
--- | ---
typename Segment | A type fulfilling the Segment Concept

###### Constructor(s)

Function | Description | Parameters
--- | --- | ---
    segment_view(Segment const & segment)
| Constructor accepting the segment to adapt. | Segment const &: segment:

###### Header

Either

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

Or

`#include <boost/geometry/views/segment_view.hpp>`

###### Complexity

Compile time

###### Example

Shows usage of the Boost.Range compatible view on a box

    #include <iostream>

    #include <boost/geometry.hpp>

    int main()
    {
        typedef boost::geometry::model::segment
            <
                boost::geometry::model::point<double, 2, boost::geometry::cs::cartesian>
            > segment_type;

        typedef boost::geometry::segment_view<segment_type> segment_view;

        segment_type segment;
        boost::geometry::assign_values(segment, 0, 0, 1, 1);

        segment_view view(segment);

        // Iterating over the points of this segment
        for (boost::range_iterator<segment_view const>::type it = boost::begin(view);
            it != boost::end(view); ++it)
        {
            std::cout << " " << boost::geometry::dsv(*it);
        }
        std::cout << std::endl;

        // Note that a segment_view is tagged as a linestring, so supports length etc.
        std::cout << "Length: " << boost::geometry::length(view) << std::endl;

        return 0;
    }

Output:

    (0, 0) (0, 4) (4, 4) (4, 0) (0, 0)
    Area: 16