boost/boost/geometry/arithmetic/arithmetic.hpp

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

// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
// Copyright (c) 2008-2012 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.

// 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_ARITHMETIC_ARITHMETIC_HPP
#define BOOST_GEOMETRY_ARITHMETIC_ARITHMETIC_HPP

#include <functional>

#include <boost/call_traits.hpp>
#include <boost/concept/requires.hpp>

#include <boost/geometry/core/coordinate_type.hpp>
#include <boost/geometry/geometries/concepts/point_concept.hpp>
#include <boost/geometry/util/for_each_coordinate.hpp>


namespace boost { namespace geometry
{

#ifndef DOXYGEN_NO_DETAIL
namespace detail
{


template <typename P>
struct param
{
    typedef typename boost::call_traits
        <
            typename coordinate_type<P>::type
        >::param_type type;
};


template <typename C, template <typename> class Function>
struct value_operation
{
    C m_value;

    inline value_operation(C const &value)
        : m_value(value)
    {}

    template <typename P, int I>
    inline void apply(P& point) const
    {
        set<I>(point, Function<C>()(get<I>(point), m_value));
    }
};

template <typename PointSrc, template <typename> class Function>
struct point_operation
{
    typedef typename coordinate_type<PointSrc>::type coordinate_type;
    PointSrc const& m_source_point;

    inline point_operation(PointSrc const& point)
        : m_source_point(point)
    {}

    template <typename PointDst, int I>
    inline void apply(PointDst& dest_point) const
    {
        set<I>(dest_point,
            Function<coordinate_type>()(get<I>(dest_point), get<I>(m_source_point)));
    }
};


template <typename C>
struct value_assignment
{
    C m_value;

    inline value_assignment(C const &value)
        : m_value(value)
    {}

    template <typename P, int I>
    inline void apply(P& point) const
    {
        set<I>(point, m_value);
    }
};

template <typename PointSrc>
struct point_assignment
{
    PointSrc const& m_source_point;

    inline point_assignment(PointSrc const& point)
        : m_source_point(point)
    {}

    template <typename PointDst, int I>
    inline void apply(PointDst& dest_point) const
    {
        set<I>(dest_point, get<I>(m_source_point));
    }
};


} // namespace detail
#endif // DOXYGEN_NO_DETAIL

/*!
    \brief Adds the same value to each coordinate of a point
    \ingroup arithmetic
    \details
    \tparam Point \tparam_point
    \param p point
    \param value value to add
 */
template <typename Point>
inline void add_value(Point& p, typename detail::param<Point>::type value)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point>) );

    for_each_coordinate(p, detail::value_operation<typename coordinate_type<Point>::type, std::plus>(value));
}

/*!
    \brief Adds a point to another
    \ingroup arithmetic
    \details The coordinates of the second point will be added to those of the first point.
             The second point is not modified.
    \tparam Point1 \tparam_point
    \tparam Point2 \tparam_point
    \param p1 first point
    \param p2 second point
 */
template <typename Point1, typename Point2>
inline void add_point(Point1& p1, Point2 const& p2)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point1>) );
    BOOST_CONCEPT_ASSERT( (concept::ConstPoint<Point2>) );

    for_each_coordinate(p1, detail::point_operation<Point2, std::plus>(p2));
}

/*!
    \brief Subtracts the same value to each coordinate of a point
    \ingroup arithmetic
    \details
    \tparam Point \tparam_point
    \param p point
    \param value value to subtract
 */
template <typename Point>
inline void subtract_value(Point& p, typename detail::param<Point>::type value)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point>) );

    for_each_coordinate(p, detail::value_operation<typename coordinate_type<Point>::type, std::minus>(value));
}

/*!
    \brief Subtracts a point to another
    \ingroup arithmetic
    \details The coordinates of the second point will be subtracted to those of the first point.
             The second point is not modified.
    \tparam Point1 \tparam_point
    \tparam Point2 \tparam_point
    \param p1 first point
    \param p2 second point
 */
template <typename Point1, typename Point2>
inline void subtract_point(Point1& p1, Point2 const& p2)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point1>) );
    BOOST_CONCEPT_ASSERT( (concept::ConstPoint<Point2>) );

    for_each_coordinate(p1, detail::point_operation<Point2, std::minus>(p2));
}

/*!
    \brief Multiplies each coordinate of a point by the same value
    \ingroup arithmetic
    \details
    \tparam Point \tparam_point
    \param p point
    \param value value to multiply by
 */
template <typename Point>
inline void multiply_value(Point& p, typename detail::param<Point>::type value)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point>) );

    for_each_coordinate(p, detail::value_operation<typename coordinate_type<Point>::type, std::multiplies>(value));
}

/*!
    \brief Multiplies a point by another
    \ingroup arithmetic
    \details The coordinates of the first point will be multiplied by those of the second point.
             The second point is not modified.
    \tparam Point1 \tparam_point
    \tparam Point2 \tparam_point
    \param p1 first point
    \param p2 second point
    \note This is *not* a dot, cross or wedge product. It is a mere field-by-field multiplication.
 */
template <typename Point1, typename Point2>
inline void multiply_point(Point1& p1, Point2 const& p2)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point1>) );
    BOOST_CONCEPT_ASSERT( (concept::ConstPoint<Point2>) );

    for_each_coordinate(p1, detail::point_operation<Point2, std::multiplies>(p2));
}

/*!
    \brief Divides each coordinate of the same point by a value
    \ingroup arithmetic
    \details
    \tparam Point \tparam_point
    \param p point
    \param value value to divide by
 */
template <typename Point>
inline void divide_value(Point& p, typename detail::param<Point>::type value)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point>) );

    for_each_coordinate(p, detail::value_operation<typename coordinate_type<Point>::type, std::divides>(value));
}

/*!
    \brief Divides a point by another
    \ingroup arithmetic
    \details The coordinates of the first point will be divided by those of the second point.
             The second point is not modified.
    \tparam Point1 \tparam_point
    \tparam Point2 \tparam_point
    \param p1 first point
    \param p2 second point
 */
template <typename Point1, typename Point2>
inline void divide_point(Point1& p1, Point2 const& p2)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point1>) );
    BOOST_CONCEPT_ASSERT( (concept::ConstPoint<Point2>) );

    for_each_coordinate(p1, detail::point_operation<Point2, std::divides>(p2));
}

/*!
    \brief Assign each coordinate of a point the same value
    \ingroup arithmetic
    \details
    \tparam Point \tparam_point
    \param p point
    \param value value to assign
 */
template <typename Point>
inline void assign_value(Point& p, typename detail::param<Point>::type value)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point>) );

    for_each_coordinate(p, detail::value_assignment<typename coordinate_type<Point>::type>(value));
}

/*!
    \brief Assign a point with another
    \ingroup arithmetic
    \details The coordinates of the first point will be assigned those of the second point.
             The second point is not modified.
    \tparam Point1 \tparam_point
    \tparam Point2 \tparam_point
    \param p1 first point
    \param p2 second point
 */
template <typename Point1, typename Point2>
inline void assign_point(Point1& p1, Point2 const& p2)
{
    BOOST_CONCEPT_ASSERT( (concept::Point<Point1>) );
    BOOST_CONCEPT_ASSERT( (concept::ConstPoint<Point2>) );

    for_each_coordinate(p1, detail::point_assignment<Point2>(p2));
}


}} // namespace boost::geometry


#endif // BOOST_GEOMETRY_ARITHMETIC_ARITHMETIC_HPP