| // Boost.Units - A C++ library for zero-overhead dimensional analysis and |
| // unit/quantity manipulation and conversion |
| // |
| // Copyright (C) 2003-2008 Matthias Christian Schabel |
| // Copyright (C) 2008 Steven Watanabe |
| // |
| // Distributed under 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_UNITS_ABSOLUTE_IMPL_HPP |
| #define BOOST_UNITS_ABSOLUTE_IMPL_HPP |
| |
| #include <iosfwd> |
| |
| #include <boost/units/config.hpp> |
| #include <boost/units/conversion.hpp> |
| #include <boost/units/heterogeneous_system.hpp> |
| #include <boost/units/units_fwd.hpp> |
| |
| namespace boost { |
| |
| namespace units { |
| |
| /// INTERNAL ONLY |
| template<class D, class S> |
| struct reduce_unit<absolute<unit<D, S> > > |
| { |
| typedef absolute<typename reduce_unit<unit<D, S> >::type> type; |
| }; |
| |
| namespace detail { |
| |
| struct undefined_affine_conversion_base { |
| static const bool is_defined = false; |
| }; |
| |
| } // namespace detail |
| |
| /// INTERNAL ONLY |
| template<class From, class To> |
| struct affine_conversion_helper : detail::undefined_affine_conversion_base { }; |
| |
| namespace detail { |
| |
| template<bool IsDefined, bool ReverseIsDefined> |
| struct affine_conversion_impl; |
| |
| template<bool ReverseIsDefined> |
| struct affine_conversion_impl<true, ReverseIsDefined> |
| { |
| template<class Unit1, class Unit2, class T0, class T1> |
| struct apply { |
| static T1 value(const T0& t0) |
| { |
| return( |
| t0 * |
| conversion_factor(Unit1(), Unit2()) + |
| affine_conversion_helper<typename reduce_unit<Unit1>::type, typename reduce_unit<Unit2>::type>::value()); |
| } |
| }; |
| }; |
| |
| template<> |
| struct affine_conversion_impl<false, true> |
| { |
| template<class Unit1, class Unit2, class T0, class T1> |
| struct apply |
| { |
| static T1 value(const T0& t0) |
| { |
| return( |
| (t0 - affine_conversion_helper<typename reduce_unit<Unit2>::type, typename reduce_unit<Unit1>::type>::value()) * |
| conversion_factor(Unit1(), Unit2())); |
| } |
| }; |
| }; |
| |
| } // namespace detail |
| |
| /// INTERNAL ONLY |
| template<class Unit1, class T1, class Unit2, class T2> |
| struct conversion_helper<quantity<absolute<Unit1>, T1>, quantity<absolute<Unit2>, T2> > |
| { |
| typedef quantity<absolute<Unit1>, T1> from_quantity_type; |
| typedef quantity<absolute<Unit2>, T2> to_quantity_type; |
| static to_quantity_type convert(const from_quantity_type& source) |
| { |
| return( |
| to_quantity_type::from_value( |
| detail::affine_conversion_impl< |
| affine_conversion_helper<typename reduce_unit<Unit1>::type, typename reduce_unit<Unit2>::type>::is_defined, |
| affine_conversion_helper<typename reduce_unit<Unit2>::type, typename reduce_unit<Unit1>::type>::is_defined |
| >::template apply<Unit1, Unit2, T1, T2>::value(source.value()) |
| ) |
| ); |
| } |
| }; |
| |
| } // namespace units |
| |
| } // namespace boost |
| |
| #endif // BOOST_UNITS_ABSOLUTE_IMPL_HPP |