Copy Tracks ?
hmmm…. Quaternions are incredibly complex equations that provide answers
to rotational problems that occur when rotational axes pass through the
"north and south poles" of the world coordinate system. They were
developed in the early 1800's to deal with gimble lock problems on large
sailing vessels, and then Ken Shoemake rediscovered them about 15 years ago
(at Xerox Parc I believe) and wrote some great papers about how to use them
with 3D animation to provide smooth rotations in all cases. The books that
Dan Silva used to develop our routines are about 700 pages long (each,
there are two of them), and every page is filled with bizarre
mult-dimensional geometry equations. If you want specific references to
the book titles, or the ACM Siggraph papers that Shoemake wrote, I can dig
them up for you.
The rotations are all relative to the objects inherent transformation
matrix. This is the orientation that the object is in when you look at it
in Object Pivot mode. (again, if you want me to look at that file of
yours, zip up a simple case and send it on over and I'll explain what's
going on for you)
– G(lad to help)