   "Freelancer" style mouse movement.
  Hi there, How do I setup rotation matrices for freelancer style mouse movement in space? I have code that rotates the model view matrix around the Y axis (left right) and then concatenates X axis movement (up down). Should I be using quaternions to avoid gimble? Even so, how do I rotate the quaternion using the mouse to achieve the right effect? Any pointers greatly appreciated. Robin 
  Simply using quaternions will not solve the problem of gimbal lock.  You have to remove all dependence on Euler angles completely, which is the only way to solve the problem.Unfortunately, I still haven''t completely understood how to get around it, so right now I''m simply hoping that the mouse never moves to _exactly_ 90 degrees. 