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/// @ref gtx_fast_square_root
namespace glm
{
// fastSqrt
template<typename genType>
GLM_FUNC_QUALIFIER genType fastSqrt(genType x)
{
GLM_STATIC_ASSERT(std::numeric_limits<genType>::is_iec559, "'fastSqrt' only accept floating-point input");
return genType(1) / fastInverseSqrt(x);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastSqrt(vec<L, T, Q> const& x)
{
return detail::functor1<vec, L, T, T, Q>::call(fastSqrt, x);
}
// fastInversesqrt
template<typename genType>
GLM_FUNC_QUALIFIER genType fastInverseSqrt(genType x)
{
return detail::compute_inversesqrt<1, genType, lowp, detail::is_aligned<lowp>::value>::call(vec<1, genType, lowp>(x)).x;
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastInverseSqrt(vec<L, T, Q> const& x)
{
return detail::compute_inversesqrt<L, T, Q, detail::is_aligned<Q>::value>::call(x);
}
// fastLength
template<typename genType>
GLM_FUNC_QUALIFIER genType fastLength(genType x)
{
GLM_STATIC_ASSERT(std::numeric_limits<genType>::is_iec559, "'fastLength' only accept floating-point inputs");
return abs(x);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER T fastLength(vec<L, T, Q> const& x)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'fastLength' only accept floating-point inputs");
return fastSqrt(dot(x, x));
}
// fastDistance
template<typename genType>
GLM_FUNC_QUALIFIER genType fastDistance(genType x, genType y)
{
return fastLength(y - x);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER T fastDistance(vec<L, T, Q> const& x, vec<L, T, Q> const& y)
{
return fastLength(y - x);
}
// fastNormalize
template<typename genType>
GLM_FUNC_QUALIFIER genType fastNormalize(genType x)
{
return x > genType(0) ? genType(1) : -genType(1);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastNormalize(vec<L, T, Q> const& x)
{
return x * fastInverseSqrt(dot(x, x));
}
}//namespace glm
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