Camera roll inversion

Hi,

I'm trying to stabilise a camera (1st person) with info. from the entity it is attached to, i.e. the pitch yaw and roll of the subject is added to the pitch yaw and roll of the camera in order to make the camera move in exactly the same manner as the subject.

Everything works OK until I spin the character through 360 degrees, for 180 of those degrees the roll and therefore the camera is inverted.

Any ideas as to why and how I can stop this inversion?

Thanks.

I suppose I should try this on the main Ogre board