Houdinin meshed fluid sim into Maya VIA Alembic Vray Motion Blur?

[Intuition]

So I've used Realflow in a case like this but today is the first time I've tried using Alembic to get a meshed fluid sim into Maya from Houdini.

Well, it works quite well. Yet I can't seem to get the motion blur to work right off. Is there some attribute I need to hook up to get the motion vector/velocity from the mesh to talk to Vray's motion blur?

Thanks.

[Intuition]

Should I upload a zip example file for testing?

I can't seem to get motion blur on a fluid sim from Houdini.

[georgi.zhekov]

Hello,

An example test scene would be great so we can see where the problem is. You can attach it here or if the file is too big just send an email to support@chaosgroup.com with link to this thread and they will provide you with an ftp access.

Thank you,

[Intuition]

This is the maya scene file which is just a hold scene with vray settings

http://www.mediafire.com/download/l0...ur_Test_v01.ma

for this alembic file which has the fluid pouring.

http://www.mediafire.com/download/36...Fluid_v002.abc

The motion blur is on. I've sucessfully used motion blur with Realflow and Vray so I imagine it is just the particular way Vray could pickup the info from this alembic concerning the houdini velocity.

[georgi.zhekov]

Hello,

Seems like the problem is in the Maya importer. If you load the alembic as VRayProxy there is motion blur and velocity channel. Can you try it this way?

Thank you,

[ivaylo.ivanov]

Maya is using color sets to represent per vertex velocities, but I can't see such set created on import.

[Intuition]

Ah ok. Yes. The alembic as a Vray proxy is working, though is there a method for subdividing/smooting at rendertime the proxymesh?

In this case it may not be an issue as the mesh will end up being much higher res later but... there are other objects that are low res SUBD.

I know that is a limitation, or was, in regards to Proxy because I realize that you can just store as much as you want.

Maybe there should be an option at create proxy time where it subD's the mesh on creation so you can just get what you need however you need it at Proxy render time. Say for instance I have a low res mesh that is getting displaced ala Zbrush/Mudbox and that at proxy creation time it does the subD calculation based on the Vray disp settings (max subDivs etc) then uses that upresed smoothed mesh for the final displacement.

[vlado]

Ah ok. Yes. The alembic as a Vray proxy is working, though is there a method for subdividing/smooting at rendertime the proxymesh?

You can control subdivision surfaces for Alembic files from the "Alembic" section of the proxy. There is an option to subdivide all geometry, or just geometry marked as subdivision surfaces in the Alembic file.

You can also subdivide/displace the proxy as any other object using a VRayDisplacement node, however in that case V-Ray will load and subdivide the entire proxy at once.

Best regards,
Vlado

[Intuition]

Ah ok, thanks for the tip Vlado, good to know that all speaks to Vray properly. Everything working here as planned now. Thanks for all the help Chaosgroup.