Q3Quaternion_MatchReflection (IM: QD3D)

Inside Macintosh: 3D Graphics Programming With QuickDraw 3D /

Chapter 20 - QuickDraw 3D Mathematical Utilities / QuickDraw 3D Mathematical Utilities Reference

QuickDraw 3D Mathematical Utilities / Managing Quaternions

Q3Quaternion_MatchReflection
You can use the Q3Quaternion_MatchReflection function to match the orientation of a quaternion.
TQ3Quaternion *Q3Quaternion_MatchReflection (
const TQ3Quaternion *q1, 
const TQ3Quaternion *q2, 
TQ3Quaternion *result);
q1
A quaternion.
q2
A quaternion.
result
On exit, a quaternion that is either q1 or the negative of q1, and that matches the orientation of q2.

DESCRIPTION
The Q3Quaternion_MatchReflection function returns, as its function result and in the result parameter, a quaternion that is either identical to the quaternion specified by the q1 parameter or is the negative of q1, depending on whether q1 or its negative matches the orientation of the quaternion specified by the q2 parameter.