VRayMesh + motion blur issues

[jeremyp]

We are having some trouble getting proxies and alembic in VRayMesh loaders to work with our motion blur settings.
In this example we are using centered motion blur, a duration of 0.5 and 2 geo samples.
Caches were exported at -0.25 and 0.25.
Red is original, green is alembic and blue is proxy.

1) Proxy (blue) lines up alembic (green) does not?



2) Adding subd to the VRayMesh (vraydisplacement) causes the motion blur offset to change.




We'd like to use alembic. Any ideas what is happening here?



This render shows the full path of the original sphere (duration set to 2 with many geometry mblur samples)


windows
maya 2015
vray 30504.26024

J

[tashko.zashev]

Hi,

I have information from our developers that we are working on some improvements on that regard, but it would be helpful if you can supply a scene for that behavior. Please send them to support@chaosgroup.com.
Thank you.

[jeremyp]

Hi Tashko,

Yes I'll send it through.

[jeremyp]

We also played with referencing the alembic file into Maya which does line up (motion blur wise) - but it does not displace at all?

Can you confirm this, is VRay loading the alembic directly at render instead of geo export from Maya to VRay?

Thanks!

[vlado]

How exactly are you referencing the Alembic file? As a GPU cache?

Best regards,
Vlado

[jeremyp]

Disregard the referenced alembic does not displace (lets just say that was user error).

No not using GPU cache at the moment, just straight referenced alembic. It seems like that may be an option for us. Loading via VRayMesh seems to be preferred though with the extra options it provides.

[svetlozar.draganov]

The alembic motion blur issue has been fixed for the next service pack. The result now is exactly the same as with a normal Maya geometry:

On top of that all Motion Blur parameters like Duration/Interval Center/Bias and etc are supported for the alembic files too.

[jeremyp]

Svetlozar,
Is this fix now available, how can we get access?

[ydm]

We expect to release the next SP within a month or so. Is this fine for you or do you need it urgently?

[jeremyp]

Yes urgently, we really need to be testing it now.

[vlado]

Ok then, please email me to vlado@chaosgroup.com and we'll sort it out.

Best regards,
Vlado