// 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