I've never used the angular velocity on the trail sop. After spending a half hour looking at it right now, I'm no closer to understanding it's use. Anyone able to provide an example of when you would want this attribute to be created?

it's similar to curl ya? so localised rotation.

I believe packed primitives/render-time instances can use angular velocity for motion blur.

Hmm… packed primitive seems to motion blur just with v, but I'll keep it in mind next time I try instances.

Example!

Yeah they'll motion blur just fine with v, in a straight line, but angular velocity gives rotational blur. If you have a packed prim spinning around at the origin v is gonna be {0,0,0}. This is why w is stored on RBDs too, it is rotation about the center of mass, which can be converted to linear point velocity but also expressed as a single vector for the whole rigid body.

I'm assuming Matt's file shows this, can't seem to open it on my dumb dang Windows machine.

Yep, the example shows a translating box next to a box rotating like a propellor. Probably should've attached an image. Indeed, should add one to this post. But I won't. (Well, I can't, can't get to the sidefx site from work atm, boo, typing this on my phone…)

Wait a sec, yes I can! Thanks iOS!

Ah! Cheers, thanks for that. (Would have responded earlier, but didn't get any notification email for some reason )