boost/boost/geometry/algorithms/detail/disjoint/box_box.hpp

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

// Copyright (c) 2007-2014 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2014 Bruno Lalande, Paris, France.
// Copyright (c) 2009-2014 Mateusz Loskot, London, UK.
// Copyright (c) 2013-2014 Adam Wulkiewicz, Lodz, Poland

// This file was modified by Oracle on 2013-2014.
// Modifications copyright (c) 2013-2014, Oracle and/or its affiliates.

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

// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.

// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_DISJOINT_BOX_BOX_HPP
#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_DISJOINT_BOX_BOX_HPP

#include <cstddef>

#include <boost/geometry/core/access.hpp>
#include <boost/geometry/core/tags.hpp>

#include <boost/geometry/algorithms/dispatch/disjoint.hpp>


namespace boost { namespace geometry
{

#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace disjoint
{


template
<
    typename Box1, typename Box2,
    std::size_t Dimension, std::size_t DimensionCount
>
struct box_box
{
    static inline bool apply(Box1 const& box1, Box2 const& box2)
    {
        if (get<max_corner, Dimension>(box1) < get<min_corner, Dimension>(box2))
        {
            return true;
        }
        if (get<min_corner, Dimension>(box1) > get<max_corner, Dimension>(box2))
        {
            return true;
        }
        return box_box
            <
                Box1, Box2,
                Dimension + 1, DimensionCount
            >::apply(box1, box2);
    }
};


template <typename Box1, typename Box2, std::size_t DimensionCount>
struct box_box<Box1, Box2, DimensionCount, DimensionCount>
{
    static inline bool apply(Box1 const& , Box2 const& )
    {
        return false;
    }
};


/*!
    \brief Internal utility function to detect if boxes are disjoint
    \note Is used from other algorithms, declared separately
        to avoid circular references
 */
template <typename Box1, typename Box2>
inline bool disjoint_box_box(Box1 const& box1, Box2 const& box2)
{
    return box_box
        <
            Box1, Box2,
            0, dimension<Box1>::type::value
        >::apply(box1, box2);
}


}} // namespace detail::disjoint
#endif // DOXYGEN_NO_DETAIL


#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{


template <typename Box1, typename Box2, std::size_t DimensionCount>
struct disjoint<Box1, Box2, DimensionCount, box_tag, box_tag, false>
    : detail::disjoint::box_box<Box1, Box2, 0, DimensionCount>
{};


} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH


}} // namespace boost::geometry


#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_DISJOINT_BOX_BOX_HPP