Re: axis-angle rotations

quat <spam@xxxxxxxx> wrote:
My book, "Computer Animation: Algorithms and Techniques," says "Note that
the axis-angle representation [of rotations] cannot be easily used when
compiling a series of rotations."

What does that mean? If you had several axis-angle rotation matrices,

Well, once you have matrices, you're using matrix representation, but
no longer using the axis-angle representation, and so the above
statement doesn't apply.

Matrices and quaternions are usable for composition of rotations.
Euler angles and axis+angle aren't.

From my understanding, axis-angle representation can be interpolated
just as well as a quaternion can by interpolating the angle and axis
vector separately.

Well, if you're so sure of that --- go ahead and try it out. Just
spare us the complaints if you don't like the results. ;-)

--
Hans-Bernhard Broeker (broeker@xxxxxxxxxxxxxxxxxxxxx)
Even if all the snow were burnt, ashes would remain.
.

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