Re: [ggt-devel] Quaternion bug?

[Justin H. <ja...@vr...>]

> Is this a bug, or am I making some bad assumptions about how quaternion 
> multiplication should work?
> 

Okay, I've made the incorrect assumption that 

quatA *= quatB;

makes quatA be the rotation combination of quatA and THEN quatB. But it 
appears that quaternions are handled like matrix multiplication so they 
are applied in reverse order. 

So to get what I want, I need

quatA = quatB * quatA;

Is this how people generally handle quaternions? I know it's the way
matrix multiplication works, but should reverse ordering also apply to
quats?

justin

-----------------------------------------
Justin Hare  <ja...@vr...>
Virtual Reality Applications Center
Iowa State University, Howe Hall
http://www.vrac.iastate.edu/~jahare
-----------------------------------------