text: /// @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
  
  