[ODE] Matrices

Si Brown si at sjbrown.co.uk
Fri May 31 07:17:01 2002

Hi all,

dMULTIPLY1_331 applies the transpose of the argument matrix to the vector 
(from a quick look at the source - so I could be wrong). Since rotation 
matrices are orthonormal this is also the inverse, so your function should 
look something like:

void dBodyGetAngularVel_BodySpace (dBodyID b, dReal* v)
  dAASSERT (b && v);
  dMULTIPLY1_331 (v,b->R,b->avel);

Hope that helps,


>From: "Tony Peguero" <Tony.Peguero@xtra.co.nz>
>To: "ODE list" <ode@q12.org>
>Subject: [ODE] Matrices
>Date: Sat, 1 Jun 2002 01:35:36 +1200
>Hi all.
>I want to create a version of the dBodyGetAngularVel function that returns
>the vector in body space rather than world space. However, I'm not so hot 
>matrix math. I notice that many of the dBody functions use the
>dMULTIPLY0_331 macro to convert a vector from body space to world space.
>What should I do to convert in the other direction?
>Thanks in advance.
>ODE mailing list

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