Velocity Pass Issues on hair...

[evanerichards]

I wanted to get some eyes on this to see if anyone recognizes anything they might have seen before.
We have a hairy character.
He has a bunch of different grooms. The velocity pass seems to work fine on everything EXCEPT for the whiskers.
Take a look at the included velocity passes for examples.

Maybe just by looking at it you really can't tell if something is messed up. But it SEEMS to me that especially frames 1 and 3 can't possibly be right. Especially if you look at how smooth the hair on the back of the head is in 5 and 6.
Any reason why the whiskers would get so blocky like that? I've been working on this problem for the better part of a week now and I'm completely out of ideas.

Thanks in advance!

[vlado]

It looks like it may be a bug or something else strange (the velocity values seem really really large). Can you get me a scene (maybe with just the whiskers) to vlado@chaosgroup.com ?

Best regards,
Vlado

[Morbid Angel]

I wanted to get some eyes on this to see if anyone recognizes anything they might have seen before.
We have a hairy character.
He has a bunch of different grooms. The velocity pass seems to work fine on everything EXCEPT for the whiskers.
Take a look at the included velocity passes for examples.
[ATTACH=CONFIG]19213[/ATTACH]
Maybe just by looking at it you really can't tell if something is messed up. But it SEEMS to me that especially frames 1 and 3 can't possibly be right. Especially if you look at how smooth the hair on the back of the head is in 5 and 6.
Any reason why the whiskers would get so blocky like that? I've been working on this problem for the better part of a week now and I'm completely out of ideas.

Thanks in advance!

Yeah we just narrowed down this bug (If its the same bug) if that is a yeti groom, yeti has incorrect data for some of the grooms so it throws the velocity way off on parts of the hair. Their suppose to have a fix in yeti 1.3.9 but Colin suggested to put a transform node at the end of the yeti graph, this should force to reevaluate each graph and produce proper motion data for each of the hairs.

Let me know if this makes sense.

[vlado]

Ah, Yeti... yes, there is that bug (I don't know why I thought the original post was for Maya hair though?)

Best regards,
Vlado

[evanerichards]

That does make sense. We did the transform trick but it did not work.
Funny it only happens on a groom where we convert strands to fibers (his whiskers). Other than that all of the hair renders velocities beautifully.