dependencies/glm/GLM/detail/func_exponential.inl

153 lines
4.2 KiB
C++

/// @ref core
/// @file glm/detail/func_exponential.inl
#include "../vector_relational.hpp"
#include "_vectorize.hpp"
#include <limits>
#include <cmath>
#include <cassert>
namespace glm{
namespace detail
{
# if GLM_HAS_CXX11_STL
using std::log2;
# else
template<typename genType>
genType log2(genType Value)
{
return std::log(Value) * static_cast<genType>(1.4426950408889634073599246810019);
}
# endif
template<length_t L, typename T, qualifier Q, bool isFloat, bool Aligned>
struct compute_log2
{
GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& v)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'log2' only accept floating-point inputs. Include <glm/gtc/integer.hpp> for integer inputs.");
return detail::functor1<vec, L, T, T, Q>::call(log2, v);
}
};
template<length_t L, typename T, qualifier Q, bool Aligned>
struct compute_sqrt
{
GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& x)
{
return detail::functor1<vec, L, T, T, Q>::call(std::sqrt, x);
}
};
template<length_t L, typename T, qualifier Q, bool Aligned>
struct compute_inversesqrt
{
GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& x)
{
return static_cast<T>(1) / sqrt(x);
}
};
template<length_t L, bool Aligned>
struct compute_inversesqrt<L, float, lowp, Aligned>
{
GLM_FUNC_QUALIFIER static vec<L, float, lowp> call(vec<L, float, lowp> const& x)
{
vec<L, float, lowp> tmp(x);
vec<L, float, lowp> xhalf(tmp * 0.5f);
vec<L, uint, lowp>* p = reinterpret_cast<vec<L, uint, lowp>*>(const_cast<vec<L, float, lowp>*>(&x));
vec<L, uint, lowp> i = vec<L, uint, lowp>(0x5f375a86) - (*p >> vec<L, uint, lowp>(1));
vec<L, float, lowp>* ptmp = reinterpret_cast<vec<L, float, lowp>*>(&i);
tmp = *ptmp;
tmp = tmp * (1.5f - xhalf * tmp * tmp);
return tmp;
}
};
}//namespace detail
// pow
using std::pow;
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> pow(vec<L, T, Q> const& base, vec<L, T, Q> const& exponent)
{
return detail::functor2<vec, L, T, Q>::call(pow, base, exponent);
}
// exp
using std::exp;
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> exp(vec<L, T, Q> const& x)
{
return detail::functor1<vec, L, T, T, Q>::call(exp, x);
}
// log
using std::log;
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> log(vec<L, T, Q> const& x)
{
return detail::functor1<vec, L, T, T, Q>::call(log, x);
}
# if GLM_HAS_CXX11_STL
using std::exp2;
# else
//exp2, ln2 = 0.69314718055994530941723212145818f
template<typename genType>
GLM_FUNC_QUALIFIER genType exp2(genType x)
{
GLM_STATIC_ASSERT(std::numeric_limits<genType>::is_iec559, "'exp2' only accept floating-point inputs");
return std::exp(static_cast<genType>(0.69314718055994530941723212145818) * x);
}
# endif
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> exp2(vec<L, T, Q> const& x)
{
return detail::functor1<vec, L, T, T, Q>::call(exp2, x);
}
// log2, ln2 = 0.69314718055994530941723212145818f
template<typename genType>
GLM_FUNC_QUALIFIER genType log2(genType x)
{
return log2(vec<1, genType>(x)).x;
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> log2(vec<L, T, Q> const& x)
{
return detail::compute_log2<L, T, Q, std::numeric_limits<T>::is_iec559, detail::is_aligned<Q>::value>::call(x);
}
// sqrt
using std::sqrt;
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> sqrt(vec<L, T, Q> const& x)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'sqrt' only accept floating-point inputs");
return detail::compute_sqrt<L, T, Q, detail::is_aligned<Q>::value>::call(x);
}
// inversesqrt
template<typename genType>
GLM_FUNC_QUALIFIER genType inversesqrt(genType x)
{
return static_cast<genType>(1) / sqrt(x);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> inversesqrt(vec<L, T, Q> const& x)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'inversesqrt' only accept floating-point inputs");
return detail::compute_inversesqrt<L, T, Q, detail::is_aligned<Q>::value>::call(x);
}
}//namespace glm
#if GLM_CONFIG_SIMD == GLM_ENABLE
# include "func_exponential_simd.inl"
#endif