mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-11-14 10:39:05 +00:00
122 lines
4.4 KiB
C++
122 lines
4.4 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2016 Bolero MURAKAMI
|
|
https://github.com/bolero-MURAKAMI/Sprout
|
|
|
|
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 SPROUT_MATH_COS_HPP
|
|
#define SPROUT_MATH_COS_HPP
|
|
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/workaround/std/cstddef.hpp>
|
|
#include <sprout/limits.hpp>
|
|
#include <sprout/detail/pow.hpp>
|
|
#include <sprout/math/detail/config.hpp>
|
|
#include <sprout/math/detail/float_compute.hpp>
|
|
//#include <sprout/math/detail/cosp.hpp>
|
|
//#include <sprout/math/detail/sinp.hpp>
|
|
#include <sprout/math/constants.hpp>
|
|
#include <sprout/math/isnan.hpp>
|
|
//#include <sprout/math/fabs.hpp>
|
|
#include <sprout/math/factorial.hpp>
|
|
#include <sprout/math/fmod.hpp>
|
|
#include <sprout/type_traits/enabler_if.hpp>
|
|
|
|
namespace sprout {
|
|
namespace math {
|
|
namespace detail {
|
|
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
|
|
inline SPROUT_CONSTEXPR float
|
|
builtin_cos(float x) {
|
|
return __builtin_cosf(x);
|
|
}
|
|
inline SPROUT_CONSTEXPR double
|
|
builtin_cos(double x) {
|
|
return __builtin_cos(x);
|
|
}
|
|
inline SPROUT_CONSTEXPR long double
|
|
builtin_cos(long double x) {
|
|
return __builtin_cosl(x);
|
|
}
|
|
#endif
|
|
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
cos_impl_1(T x2, std::size_t n, std::size_t last) {
|
|
return last - n == 1
|
|
? (n % 2 ? -1 : 1) * sprout::detail::pow_n(x2, n) / sprout::math::unchecked_factorial<T>(2 * n)
|
|
: sprout::math::detail::cos_impl_1(x2, n, n + (last - n) / 2)
|
|
+ sprout::math::detail::cos_impl_1(x2, n + (last - n) / 2, last)
|
|
;
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR T
|
|
cos_impl(T x) {
|
|
return T(1) + sprout::math::detail::cos_impl_1(
|
|
sprout::detail::pow2(sprout::math::fmod(x, sprout::math::two_pi<T>())),
|
|
1, sprout::math::factorial_limit<T>() / 2 + 1
|
|
);
|
|
}
|
|
|
|
// !!! OLD:
|
|
// template<typename T>
|
|
// inline SPROUT_CONSTEXPR T
|
|
// cos_impl_2(T x) {
|
|
// return x <= sprout::math::quarter_pi<T>() ? -sprout::math::detail::cosp(x)
|
|
// : x <= sprout::math::half_pi<T>() ? -sprout::math::detail::sinp(sprout::math::half_pi<T>() - x)
|
|
// : x <= sprout::math::three_quarters_pi<T>() ? sprout::math::detail::sinp(x - sprout::math::half_pi<T>())
|
|
// : sprout::math::detail::cosp(sprout::math::pi<T>() - x)
|
|
// ;
|
|
// }
|
|
// template<typename T>
|
|
// inline SPROUT_CONSTEXPR T
|
|
// cos_impl_1(T x) {
|
|
// return x > sprout::math::pi<T>() ? sprout::math::detail::cos_impl_2(x - sprout::math::pi<T>())
|
|
// : x <= sprout::math::quarter_pi<T>() ? sprout::math::detail::cosp(x)
|
|
// : x <= sprout::math::half_pi<T>() ? sprout::math::detail::sinp(sprout::math::half_pi<T>() - x)
|
|
// : x <= sprout::math::three_quarters_pi<T>() ? -sprout::math::detail::sinp(x - sprout::math::half_pi<T>())
|
|
// : -sprout::math::detail::cosp(sprout::math::pi<T>() - x)
|
|
// ;
|
|
// }
|
|
// template<typename T>
|
|
// inline SPROUT_CONSTEXPR T
|
|
// cos_impl(T x) {
|
|
// return sprout::math::detail::cos_impl_1(sprout::math::fmod(sprout::math::fabs(x), sprout::math::two_pi<T>()));
|
|
// }
|
|
} // namespace detail
|
|
//
|
|
// cos
|
|
//
|
|
template<
|
|
typename FloatType,
|
|
typename sprout::enabler_if<std::is_floating_point<FloatType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR FloatType
|
|
cos(FloatType x) {
|
|
return sprout::math::isnan(x) ? x
|
|
: x == sprout::numeric_limits<FloatType>::infinity() || x == -sprout::numeric_limits<FloatType>::infinity()
|
|
? -sprout::numeric_limits<FloatType>::quiet_NaN()
|
|
#if SPROUT_USE_BUILTIN_CMATH_FUNCTION
|
|
: sprout::math::detail::builtin_cos(x)
|
|
#else
|
|
: x == 0 ? FloatType(1)
|
|
: static_cast<FloatType>(sprout::math::detail::cos_impl(static_cast<typename sprout::math::detail::float_compute<FloatType>::type>(x)))
|
|
#endif
|
|
;
|
|
}
|
|
template<
|
|
typename IntType,
|
|
typename sprout::enabler_if<std::is_integral<IntType>::value>::type = sprout::enabler
|
|
>
|
|
inline SPROUT_CONSTEXPR double
|
|
cos(IntType x) {
|
|
return sprout::math::cos(static_cast<double>(x));
|
|
}
|
|
} // namespace math
|
|
|
|
using sprout::math::cos;
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_MATH_COS_HPP
|