[ODE] FW: Quick dQuaternion question

[Andrew Arcilla]

Just forwarding to the list for everyone's reference.  Thanks Tomek.

-----Original Message-----
From: tomek [mailto:klinikk at o2.pl] 
Sent: Friday, June 02, 2006 6:17 PM
To: Andrew Arcilla
Subject: Re: [ODE] Quick dQuaternion question

Hello Andrew,

> Hello,

> I just want some confirmation about the dQuaternion object.  So, could
> someone please tell me how ODE interprets the order of the dQuaternion
> array?  In other words, does dQuaternion[0] refer to W or X?

>From ODE Manual:

"9.1. Rotation functions
Rigid body orientations are represented with quaternions. A quaternion
is four numbers [cos( theta /2),sin( theta /2)*u] where theta is a
rotation angle and u is a unit length rotation axis."

The order is [W,X,Y,Z].

-- 
Tomek