Alembic, Vrscene and latest nightly

V-Ray V-Ray for Houdini General
1

Hi Guys,

Been reading through a lot of the posts here and Chaos devs seem to be pushing Alembic as the preferred file format. I’m ok with that but I have one issue I need to resolve in order to be able to use it instead of vrscene in my workflow.
I’m using vrscene as a proxy for assets like vegetation and I like how it lets you reduce the viewport poly count on a mesh. How do you do that with Alembic, there is no Viewport Preview Faces limit option.
Also by the way Alembic is about 75% larger file size than vrscene.
And finally, vrscene export via Vray render node in /out is broken, doesn’t let you export as vrscene in the latest nightly. (Well it exports and makes the file, but when you bring it back in its blank)

Vray - vray_adv_62005
Houdini - FX 20.0.547

2

> lot of the posts here and Chaos devs seem to be pushing Alembic as the preferred file format

Yes, it’s preferred over vrmesh, but not vrscene.

> but when you bring it back in its blank

This is probably because new instancing backend and vrscene preview generation, we’ll fix this… It should still render though.
As a workaround you could switch ROP → Translator → Instancing Backend to Legacy before vrscene export.

But why do you want to export vrscene from Houdini and then bring it back to Houdini?
It doesn’t sound very efficient to me. vrscene format was never designed to be an asset sharing format… It could be used to some extent though…

3

Hi Bdancer,

Thanks for the quick response.

Roger that on all comments.

Ok so I’m using vrscene as a proxy mechanism. Eg one species of tree that I’ve setup and shaded in Houdini, export as vrscene (only the tree model and shaders in it). Then bring it into whatever scene and instance as required (usually copy to points), basically building my asset library up as vrscene files. Seems to be good on memory, good on file size and faster to first pix in rendering.

I’m in archviz and require 1000s of trees in a scene, vrscene handles it well and lets you reduce viewport polys to be manageable on the vrscene node. Is this not the correct way to do vray proxies in houdini?

FYI I’m about three months in on my transition from Vray and Maya to Vray and Houdini. I’ve been converting my whole pipeline over to Houdini, its been doing well, love how Houdini works.

Thanks.

4

> Is this not the correct way to do vray proxies in houdini?

vray proxies is vrmesh file, vrscene is not vrmesh.

> Seems to be good on memory, good on file size and faster to first pix in rendering.

Well, then I’m glad vrscene works for you :slight_smile:

5

Yeah don’t use vrmesh, had issues with it and find it unreliable. Looses shaders etc.

Vrmesh seems to be more reliable and keeps the shaders.

Thanks.

6

> vrmesh .. Looses shaders etc.

vrmesh is geometry data only, there are no shaders baked into.

vrscene is full render ready scene description, and it has shaders, yes.

7

hi. i used to email support for access to nightlies. who do i contact now? think email addresses have changed?
i couldnt find a post telling me how to get access so dont know where to post this question.
thanks

8

And what about USD?
Runns away :smile:

9

Dear @the_one_j , hello.

Please use our contact form.
Under Request Type choose License Management.