boost/boost/geometry/iterators/point_iterator.hpp

// Boost.Geometry (aka GGL, Generic Geometry Library)

// Copyright (c) 2014, Oracle and/or its affiliates.

// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle

// Licensed under the Boost Software License version 1.0.
// http://www.boost.org/users/license.html

#ifndef BOOST_GEOMETRY_ITERATORS_POINT_ITERATOR_HPP
#define BOOST_GEOMETRY_ITERATORS_POINT_ITERATOR_HPP

#include <boost/assert.hpp>
#include <boost/iterator/iterator_adaptor.hpp>
#include <boost/mpl/assert.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/range.hpp>

#include <boost/geometry/core/exterior_ring.hpp>
#include <boost/geometry/core/interior_rings.hpp>
#include <boost/geometry/core/tags.hpp>

#include <boost/geometry/iterators/dispatch/point_iterator.hpp>
#include <boost/geometry/iterators/detail/point_iterator/iterator_type.hpp>


namespace boost { namespace geometry
{


#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{


// specializations for points_begin


template <typename Linestring>
struct points_begin<Linestring, linestring_tag>
{
    static inline typename detail::point_iterator::iterator_type
        <
            Linestring
        >::type
    apply(Linestring& linestring)
    {
        return boost::begin(linestring);
    }
};


template <typename Ring>
struct points_begin<Ring, ring_tag>
{
    static inline typename detail::point_iterator::iterator_type<Ring>::type
    apply(Ring& ring)
    {
        return boost::begin(ring);
    }
};


template <typename Polygon>
struct points_begin<Polygon, polygon_tag>
{
    typedef typename detail::point_iterator::iterator_type
        <
            Polygon
        >::type return_type;

    static inline return_type apply(Polygon& polygon)
    {
        typedef typename return_type::second_iterator_type flatten_iterator;

        return return_type
            (boost::begin(geometry::exterior_ring(polygon)),
             boost::end(geometry::exterior_ring(polygon)),
             flatten_iterator(boost::begin(geometry::interior_rings(polygon)),
                              boost::end(geometry::interior_rings(polygon))
                              ),
             flatten_iterator(boost::begin(geometry::interior_rings(polygon)),
                              boost::end(geometry::interior_rings(polygon))
                              )
             );
    }
};


template <typename MultiPoint>
struct points_begin<MultiPoint, multi_point_tag>
{
    static inline typename detail::point_iterator::iterator_type
        <
            MultiPoint
        >::type
    apply(MultiPoint& multipoint)
    {
        return boost::begin(multipoint);
    }
};


template <typename MultiLinestring>
struct points_begin<MultiLinestring, multi_linestring_tag>
{
    typedef typename detail::point_iterator::iterator_type
        <
            MultiLinestring
        >::type return_type;

    static inline return_type apply(MultiLinestring& multilinestring)
    {
        return return_type(boost::begin(multilinestring),
                           boost::end(multilinestring));
    }
};


template <typename MultiPolygon>
struct points_begin<MultiPolygon, multi_polygon_tag>
{
    typedef typename detail::point_iterator::iterator_type
        <
            MultiPolygon
        >::type return_type;

    static inline return_type apply(MultiPolygon& multipolygon)
    {
        return return_type(boost::begin(multipolygon),
                           boost::end(multipolygon));
    }
};

} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH





#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{


// specializations for points_end


template <typename Linestring>
struct points_end<Linestring, linestring_tag>
{
    static inline typename detail::point_iterator::iterator_type
        <
            Linestring
        >::type
    apply(Linestring& linestring)
    {
        return boost::end(linestring);
    }
};


template <typename Ring>
struct points_end<Ring, ring_tag>
{
    static inline typename detail::point_iterator::iterator_type<Ring>::type
    apply(Ring& ring)
    {
        return boost::end(ring);
    }
};


template <typename Polygon>
struct points_end<Polygon, polygon_tag>
{
    typedef typename detail::point_iterator::iterator_type
        <
            Polygon
        >::type return_type;

    static inline return_type apply(Polygon& polygon)
    {
        typedef typename return_type::second_iterator_type flatten_iterator;

        return return_type
            (boost::end(geometry::exterior_ring(polygon)),
             flatten_iterator(boost::begin(geometry::interior_rings(polygon)),
                              boost::end(geometry::interior_rings(polygon))
                              ),
             flatten_iterator( boost::end(geometry::interior_rings(polygon)) )
             );
    }
};


template <typename MultiPoint>
struct points_end<MultiPoint, multi_point_tag>
{
    static inline typename detail::point_iterator::iterator_type
        <
            MultiPoint
        >::type
    apply(MultiPoint& multipoint)
    {
        return boost::end(multipoint);
    }
};


template <typename MultiLinestring>
struct points_end<MultiLinestring, multi_linestring_tag>
{
    typedef typename detail::point_iterator::iterator_type
        <
            MultiLinestring
        >::type return_type;

    static inline return_type apply(MultiLinestring& multilinestring)
    {
        return return_type(boost::end(multilinestring));
    }
};


template <typename MultiPolygon>
struct points_end<MultiPolygon, multi_polygon_tag>
{
    typedef typename detail::point_iterator::iterator_type
        <
            MultiPolygon
        >::type return_type;

    static inline return_type apply(MultiPolygon& multipolygon)
    {
        return return_type(boost::end(multipolygon));
    }
};


} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH


// MK:: need to add doc here
template <typename Geometry>
class point_iterator
    : public boost::iterator_adaptor
        <
            point_iterator<Geometry>,
            typename detail::point_iterator::iterator_type<Geometry>::type
        >
{
private:
    template <typename OtherGeometry> friend class point_iterator;
    template <typename G> friend inline point_iterator<G> points_begin(G&);
    template <typename G> friend inline point_iterator<G> points_end(G&);

    inline point_iterator(typename point_iterator::base_type const& base_it)
        : point_iterator::iterator_adaptor_(base_it) {}

public:
    inline point_iterator() {}

    template <typename OtherGeometry>
    inline point_iterator(point_iterator<OtherGeometry> const& other)
        : point_iterator::iterator_adaptor_(other.base())
    {
        static const bool is_conv
            = boost::is_convertible<
                typename detail::point_iterator::iterator_type
                    <
                        OtherGeometry
                    >::type,
                typename detail::point_iterator::iterator_type
                    <
                        Geometry
                    >::type
            >::value;

        BOOST_MPL_ASSERT_MSG((is_conv),
                             NOT_CONVERTIBLE,
                             (point_iterator<OtherGeometry>));
    }
};


// MK:: need to add doc here
template <typename Geometry>
inline point_iterator<Geometry>
points_begin(Geometry& geometry)
{
    return dispatch::points_begin<Geometry>::apply(geometry);
}


// MK:: need to add doc here
template <typename Geometry>
inline point_iterator<Geometry>
points_end(Geometry& geometry)
{
    return dispatch::points_end<Geometry>::apply(geometry);
}


}} // namespace boost::geometry

#endif // BOOST_GEOMETRY_ITERATORS_POINT_ITERATOR_HPP