Hi all.

I have some very heavy geometry going out of Houdini to (shudders) Maya and I we set up the gubbins so that it can bring in all the attributes I desire for use in Arnold and render them out fine.

However, the .abc files are single files and need to cook in one strait hit which can take some considerable time pending what you are doing.

Is there a way to get either….

• An Alembic to cook on a farm (deadline) in a distributed way?
  
• A 1 file per frame alternative that can pass attributes through when read in maya reliably?
  

Does the Houdini engine integration with Maya bring through all these Attributes on geometry? Haven't played with that yet to be fair. Might be the answer but then that would mean more licenses to pay for.

Many thanks all,
Rich.

Richard Costin
Is there a way to get either….

An Alembic to cook on a farm (deadline) in a distributed way?
A 1 file per frame alternative that can pass attributes through when read in maya reliably?

Yes and yes.

On the alembic rop, you can put a frame number expression in the file name, e.g. ‘out.$F4.abc’, to create an abc per frame. You may also have to uncheck ‘Render Full Range’. Then submit as a normal job of frames to the farm. I'm not familiar with deadline, but in my farm software this is controlled with the chunking size. Setting it to one means each work item executes a single frame.

I'm not sure how abc frames are read into maya, but I know it is possible as this method is used for rendering heavy caches such as fluid simulations in VRay with maya at my studio. One caveat is that motion blur requires requires velocity to work as each cache only contains one frame.

Maya natively won't read sequenced ABC files but VRay and Arnold's proxy loaders can, at the expense of the geometry being immutable. It's much easier on the viewport, too.

Thanks guys, appreciated.

I know we couldn't get them to read in soft or maya, but the arnold proxy loader could work for some scenes where all it needs is to render in place.

I have rendered out .ass files from houdini before that render super quickly in maya/arnold at the expense of a slower export time for some elements, although that can be offloaded to the farm. Really helped out on a super heavy geometry rbd cache.

Oh to simply stay in Houdini…….

Cheers,
Rich.

Hi
Even if you want to import sequenced abc files with Maya native alembic, there is some free script for doing that.

The only limitation of Maya native alembic is it doesn't support particles when Houdini Alembic does.

About alternative faster format instead of Alembic, It's vdb !

I know there is new feature in vdb which let you to export other type of geometries not just volume and it is so fast and efficient.

But currently it is using by some vfx companies and I think it's not released for public yet !


My suggestion about your project is try to render all of fx elements inside of Houdini and others inside of Maya.

Thanks Sadjad, will keep my ear to the ground on that!

If poss I like to keep everything inside houdini but not always viable!

Cheers,
Rich.

The Alembic ROP can be used to generate an Alembic archive per frame by putting an expression in the “File Name” parameter like “output$F4.abc”

Consider using the “abcstitcher” command line tool (from the Alembic project) to combine the per frame Alembic archives into a single archive.

Save out per frame Alembics, and get Multi-Verse [j-cube.jp].
It will change your life. All houdini geo is supported, so particles! Also, all per point attrs too.
Everything comes in delayed load streamed to VP2, your scenes will stay light as the Arnold procedural
translates everything at render time.


Cheers

Lewis