text: #pragma once
  #ifndef MATH_QUATERNION_H
  #define MATH_QUATERNION_H
  //------------------------------------------------------------------------------
  /**
      @class Math::quaternion
  
      Nebula's quaternion class.
  
      (C) 2004 RadonLabs GmbH
      (C) 2013-2016 Individual contributors, see AUTHORS file
  
  */
  
  #if __USE_XNA
  #include "math/xnamath/xna_quaternion.h"
  #elif __USE_VECMATH
  #include "math/vecmath/vec_quaternion.h"
  #else
  #error "quaternion class not implemented!"
  #endif
  //-------------------------------------------------------------------
  #endif
  