[SOLVED] CCL:Ambiguous rotation values

On Tue, 1 Jul 2003 17:53:48 -0400 Rick Venable wrote:
 >It occurs to me that for a unit vector and it's inverse, and rotations
 >of A that differ by pi, you will get the same relative orientation.
 >Try just sampling A from 0 to pi
 Yes, that was one part of the problem, but that was not all.
 We changed the sampling of phi and theta (angles that define axis direction)
 to be from 0 to PI (thus limiting the axis direction to one hemisphere), but
 the problem was still present. Then we noted two points:
 1. If A (the rotation angle) equals zero then every <phi, theta>
 combination
 will result in the same rotation (or should I say lack of rotation)
 2. If the direction of the rotation axis is parallel to Z (theta==0), for a
 given A angle, all phi values will result in the same rotation.
 Thanks for help
 --
 Boris Gorelik
 -= ( 2*b || !(2*b)) That's the question =-
 Wed, 02/Jul/2003, 2 Tamuz 5763
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