Real-Time Physics Simulation Forum

Hi folks,

Sorry for the noob question, but I got my boxes stacking by dividing the angular velocity by 1/2. Erin's Iterative dynamics states that the *quaternion* integration is achieved by:

q2 = q1 + dt/2 * q1 * w2

The factor of 1/2 in there seems to be required for the quaternion integration. I don't do my integration via quaternions, I do it with matrix math. Do I still need to divide by 2 for a matrix integration?

Thanks in advance,
Mike

Here is my success story*. It's got an asterisk because it's dependent on dividing angular velocity by 2, lol.



Mike

Nevermind! It works even with angular velocity not divided by 2. I don't know what I did, but it does the teeter-totter that Erin describes in his paper and then stabilizes due to the caching of lambda values. Oh, and the bias calculation for the normal constraint: I'm not dividing by anything--it's straight up difference in velocity + penetration / dt. It's working and I'm happy. I can get some sleep now.

Mike