vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/geometry/arithmetic/determinant.hpp

79 lines
2.2 KiB
C++
Raw Normal View History

// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
// Copyright (c) 2008-2012 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
// 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_DETERMINANT_HPP
#define BOOST_GEOMETRY_ARITHMETIC_DETERMINANT_HPP
#include <cstddef>
#include <boost/geometry/core/access.hpp>
#include <boost/geometry/geometries/concepts/point_concept.hpp>
#include <boost/geometry/util/select_coordinate_type.hpp>
#include <boost/numeric/conversion/cast.hpp>
namespace boost { namespace geometry
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail
{
template <typename ReturnType, typename U, typename V>
class calculate_determinant
{
template <typename T>
static inline ReturnType rt(T const& v)
{
return boost::numeric_cast<ReturnType>(v);
}
public :
static inline ReturnType apply(U const& ux, U const& uy
, V const& vx, V const& vy)
{
return rt(ux) * rt(vy) - rt(uy) * rt(vx);
}
};
template <typename ReturnType, typename U, typename V>
inline ReturnType determinant(U const& ux, U const& uy
, V const& vx, V const& vy)
{
return calculate_determinant
<
ReturnType, U, V
>::apply(ux, uy, vx, vy);
}
template <typename ReturnType, typename U, typename V>
inline ReturnType determinant(U const& u, V const& v)
{
BOOST_CONCEPT_ASSERT( (concepts::ConstPoint<U>) );
BOOST_CONCEPT_ASSERT( (concepts::ConstPoint<V>) );
return calculate_determinant
<
ReturnType,
typename geometry::coordinate_type<U>::type,
typename geometry::coordinate_type<V>::type
>::apply(get<0>(u), get<1>(u), get<0>(v), get<1>(v));
}
} // namespace detail
#endif // DOXYGEN_NO_DETAIL
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ARITHMETIC_DETERMINANT_HPP