raytracing/Glm/gtx/fast_square_root.hpp

///////////////////////////////////////////////////////////////////////////////////
/// OpenGL Mathematics (glm.g-truc.net)
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/// @ref gtx_fast_square_root
/// @file glm/gtx/fast_square_root.hpp
/// @date 2006-01-04 / 2011-06-07
/// @author Christophe Riccio
///
/// @see core (dependence)
///
/// @defgroup gtx_fast_square_root GLM_GTX_fast_square_root
/// @ingroup gtx
/// 
/// @brief Fast but less accurate implementations of square root based functions.
/// - Sqrt optimisation based on Newton's method, 
/// www.gamedev.net/community/forums/topic.asp?topic id=139956
/// 
/// <glm/gtx/fast_square_root.hpp> need to be included to use these functionalities.
///////////////////////////////////////////////////////////////////////////////////

#ifndef GLM_GTX_fast_square_root
#define GLM_GTX_fast_square_root GLM_VERSION

// Dependency:
#include "../glm.hpp"

#if(defined(GLM_MESSAGES) && !defined(glm_ext))
#	pragma message("GLM: GLM_GTX_fast_square_root extension included")
#endif

namespace glm
{
	/// @addtogroup gtx_fast_square_root
	/// @{

	//! Faster than the common sqrt function but less accurate.
	//! From GLM_GTX_fast_square_root extension.
	template <typename genType> 
	genType fastSqrt(genType const & x);

	//! Faster than the common inversesqrt function but less accurate.
	//! From GLM_GTX_fast_square_root extension.
	template <typename genType> 
	genType fastInverseSqrt(genType const & x);
		
	//! Faster than the common length function but less accurate.
	//! From GLM_GTX_fast_square_root extension.
	template <typename genType> 
	typename genType::value_type fastLength(genType const & x);

	//! Faster than the common distance function but less accurate.
	//! From GLM_GTX_fast_square_root extension.
	template <typename genType> 
	typename genType::value_type fastDistance(genType const & x, genType const & y);

	//! Faster than the common normalize function but less accurate.
	//! From GLM_GTX_fast_square_root extension.
	template <typename genType> 
	genType fastNormalize(genType const & x);

	/// @}
}// namespace glm

#include "fast_square_root.inl"

#endif//GLM_GTX_fast_square_root