Re: r * p * h

"Philippe C.D. Robert" <[email protected]> Fri, 12 Jul 2002 19:59:49 +0200
Newsgroups gmane.comp.gnu.3dkit.general
Message-ID <[email protected]>
Hi Brent,

On Friday, July 12, 2002, at 07:02 PM, Brent Gulanowski wrote:
> In the function G3DMakeEulerTransform4f, this comment:
>
>   /*
>    * Euler(h,p,r) := Rz(r) * Rx(p) * Ry(h)
>    *
>    */
>
> doesn't seem to be supported by the code which follows, where the 
> angles are applied
>
> Ry(h) * Rx(p) * Rz(r) -- where multiplication is done right to left, 
> these being matrices.
>
> I think the convention is reflected in the comment, not in the code. 
> Alternately, please explain how the existing setup is best used.

Nope, read carefully through the code! What is done is:

1. create Rz
2. create Rx, calculate Rzx = Rz * Rx
3. create Ry, calculate Euler = Rzx * Ry

which is what it should be: Rz * Rx * Ry.

-Phil
--
Philippe C.D. Robert
http://www.nice.ch/~phip