text: ///////////////////////////////////////////////////////////////////////////////////
  /// OpenGL Mathematics (glm.g-truc.net)
  ///
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  /// furnished to do so, subject to the following conditions:
  /// 
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  /// all copies or substantial portions of the Software.
  /// 
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  ///		By making use of the Software for military purposes, you choose to make
  ///		a Bunny unhappy.
  /// 
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  /// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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  /// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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  ///
  /// @ref gtx_color_space_YCoCg
  /// @file glm/gtx/color_space_YCoCg.inl
  /// @date 2008-10-28 / 2011-06-07
  /// @author Christophe Riccio
  ///////////////////////////////////////////////////////////////////////////////////////////////////
  
  namespace glm
  {
  	template <typename T, precision P>
  	GLM_FUNC_QUALIFIER tvec3<T, P> rgb2YCoCg
  	(
  		tvec3<T, P> const & rgbColor
  	)
  	{
  		tvec3<T, P> result;
  		result.x/*Y */ =   rgbColor.r / T(4) + rgbColor.g / T(2) + rgbColor.b / T(4);
  		result.y/*Co*/ =   rgbColor.r / T(2) + rgbColor.g * T(0) - rgbColor.b / T(2);
  		result.z/*Cg*/ = - rgbColor.r / T(4) + rgbColor.g / T(2) - rgbColor.b / T(4);
  		return result;
  	}
  
  	template <typename T, precision P>
  	GLM_FUNC_QUALIFIER tvec3<T, P> YCoCg2rgb
  	(
  		tvec3<T, P> const & YCoCgColor
  	)
  	{
  		tvec3<T, P> result;
  		result.r = YCoCgColor.x + YCoCgColor.y - YCoCgColor.z;
  		result.g = YCoCgColor.x				   + YCoCgColor.z;
  		result.b = YCoCgColor.x - YCoCgColor.y - YCoCgColor.z;
  		return result;
  	}
  
  	template <typename T, precision P, bool isInteger>
  	class compute_YCoCgR {
  	public:
  		static GLM_FUNC_QUALIFIER tvec3<T, P> rgb2YCoCgR
  		(
  			tvec3<T, P> const & rgbColor
  		)
  		{
  			tvec3<T, P> result;
  			result.x/*Y */ = rgbColor.g / T(2) + (rgbColor.r + rgbColor.b) / T(4);
  			result.y/*Co*/ = rgbColor.r - rgbColor.b;
  			result.z/*Cg*/ = rgbColor.g - (rgbColor.r + rgbColor.b) / T(2);
  			return result;
  		}
  
  		static GLM_FUNC_QUALIFIER tvec3<T, P> YCoCgR2rgb
  		(
  			tvec3<T, P> const & YCoCgRColor
  		)
  		{
  			tvec3<T, P> result;
  			T tmp = YCoCgRColor.x - (YCoCgRColor.z / T(2));
  			result.g = YCoCgRColor.z + tmp;
  			result.b = tmp - (YCoCgRColor.y / T(2));
  			result.r = result.b + YCoCgRColor.y;
  			return result;
  		}
  	};
  
  	template <typename T, precision P>
  	class compute_YCoCgR<T, P, true> {
  	public:
  		static GLM_FUNC_QUALIFIER tvec3<T, P> rgb2YCoCgR
  		(
  			tvec3<T, P> const & rgbColor
  		)
  		{
  			tvec3<T, P> result;
  			result.y/*Co*/ = rgbColor.r - rgbColor.b;
  			T tmp = rgbColor.b + (result.y >> 1);
  			result.z/*Cg*/ = rgbColor.g - tmp;
  			result.x/*Y */ = tmp + (result.z >> 1);
  			return result;
  		}
  
  		static GLM_FUNC_QUALIFIER tvec3<T, P> YCoCgR2rgb
  		(
  			tvec3<T, P> const & YCoCgRColor
  		)
  		{
  			tvec3<T, P> result;
  			T tmp = YCoCgRColor.x - (YCoCgRColor.z >> 1);
  			result.g = YCoCgRColor.z + tmp;
  			result.b = tmp - (YCoCgRColor.y >> 1);
  			result.r = result.b + YCoCgRColor.y;
  			return result;
  		}
  	};
  
  	template <typename T, precision P>
  	GLM_FUNC_QUALIFIER tvec3<T, P> rgb2YCoCgR
  	(
  		tvec3<T, P> const & rgbColor
  	)
  	{
  		return compute_YCoCgR<T, P, std::numeric_limits<T>::is_integer>::rgb2YCoCgR(rgbColor);
  	}
  
  	template <typename T, precision P>
  	GLM_FUNC_QUALIFIER tvec3<T, P> YCoCgR2rgb
  	(
  		tvec3<T, P> const & YCoCgRColor
  	)
  	{
  		return compute_YCoCgR<T, P, std::numeric_limits<T>::is_integer>::YCoCgR2rgb(YCoCgRColor);
  	}
  }//namespace glm
  