title: How does this Quaternion rotation code work?
body: <p>I'm trying to understand how the quaternion rotations work, I found this mini tutorial <a href="http://www.julapy.com/blog/2008/12/22/quaternion-rotation/" rel="noreferrer">http://www.julapy.com/blog/2008/12/22/quaternion-rotation/</a> but He makes some assumptions that I can't workout, like how can I do "<em>work out the rotation vectors around each axis, simply by rotating the vector around an axis.</em>" and how does he calculate angleDegreesX, angleDegreesY and angleDegreesZ?</p>
  
  <p>Can some one provide a working example or explanation?</p>