Realflow alembic motionblur

[pechart]

Hi!
I have to render some realflow meshes, which I got exported as abc meshes. The FX guy said he baked the velocity into the mesh, but I can't render it with motionblur.
I import the ABC via the maya pipeline cache. I don't want to use the vray proxy, because we want to do some deformations on the meshes in maya before rendering.

Is there a chance to render those meshes with motion blur when doing the import with maya? I guess not, but maybe someone figured something out here.

Thanks a lot!

[vlado]

First of all, if you do deformations on the mesh, the stored velocity channel will be useless as it doesn't take into account those deformations.

In any case, you can specify the name of the velocity channel in the "Motion vector color set" of the mesh (see attachment).

Best regards,
Vlado

[pechart]

Thanks. I hope our deformations are small enough to work, so I already took that into account. Great, I'll try the attr, thanks a lot!

[pechart]

So, I checked my mesh with SOuP and it definitely has data in the vertex channel "velocity".
But when I enter that channel into the motionVectorColorSet and enable motionblur in vray still nothing happens in the render and the velocity pass. Sorry for this "step by step" questions, but we really have get this to work, if it's possible.

(I'm doing this on an undeformed mesh, of course.)


EDIT: I just recognized that the velocity in my mesh is a float. Should be a vector, I guess. Hmm

[vlado]

If you still can't get it to work, it would be best to post a scene or send it to me at vlado@chaosgroup.com to check out.

Best regards,
Vlado

[ivaylo.ivanov]

Yep, velocity should be a vector.

[pechart]

Hmm, dunno what's happening. Has anyone managed this workflow properly from realflow via maya abc to vray3? We use standart realflow particle meshes, no hybrido.

[pechart]

Okay, as I couldn't find a solution we have to choose another way to render that stuff.

I tested this in mental ray and it worked pretty good. I just imported everything as a regular .bin sequence and applied some deformers to the mesh. In mental ray everything worked well, the results are okay.

Now, is it possible to render that .bin sequence with motionblur in vray? I didn't work right "out of the box", but maybe I'm missing something.

I can't believe that this is something so special, that there's no real solution to get it to work. And I really don't want to mix vray and mray renderings for this job. (My workaround would be to render only the motion vectors in mray and comp that with my vray beauty render. But that's not the way I want to do it, obviously.)

Thanks!

[Dan Andersen]

Rendering a Reaflow bin sequence with VRay motion blur works right out of the box for me. Haven't tried with RF alembic.

[pechart]

What? Really? Which version are you using? We are on Maya2015 EXT1 SP6 with V-Ray for Maya version 3.05.04, revision 25656 from Mar 25 2015.
Do you use hybrido or particle meshes from RF?


I'm losing my mind here trying to get this to work.

Thanks for the feedback!

[Dan Andersen]

Standard RF particle mesher. M2012/M2014, any VRay 2/3 version we've run, I believe. I've used it on a few different shows, and just never had any problems with it.

[pechart]

Would you mind if I send you some frames of the bin sequenze and you'd give it a quick shot?

[Dan Andersen]

Would you mind if I send you some frames of the bin sequenze and you'd give it a quick shot?

sure, no problem

[pechart]

I sent you a PM.

[Dan Andersen]

Our default mblur settings are duration=0.5 (180 degree shutter), intervalCenter=0 and mblur works fine on your sequence with those settings. However, I think the VRay defaults are duration=1, intervalCenter=0.5 and those don't work for me. So I guess my 'works out of the box' comment isn't valid - it's just that we never actually use the default settings, so for me it's never been a problem. Hope this helps.