Caching Vray Fur?

[jgriffin]

Is there any way to cache vray fur? I have several shots of a grassy field that uses vray fur for the grass and the "compiling geometry" time is from 7 to 20 minutes depending on the render node. The render itself is quite fast, only taking a few minutes.

The grass isn't animated at all so it'd be really nice if the geometry only had to compile once.

I've tried caching to vrmesh and vrscene but they don't make any difference.

Thanks!

[Mihail.Djurev]

Caching V-Ray fur is not currently possible. But 20 minutes sounds a bit too much. Could you send us a log so we can see what's going on?

[Dan Andersen]

Yeah, we've run into the same problem whenever we've been trying to cover more than a few square meters with grass - geo compile takes forever! So pretty much always ended up using VRayScatter instead. Would really like to have VRay Fur as an option for this scenario though, so it would be great if compile time could be brought down dramatically..

[Dan Andersen]

.. Here's a script that will create a field of 'grass' 10x10 meters (in centimeters):

import pymel.core as pm
import maya.mel as mel

geo = pm.polyPlane()[0]
geo.setScale((1000, 1, 1000))

fur = pm.PyNode(mel.eval('vray objectProperties add_multiple VRayFur;')[0])
fur.length.set(5)
fur.thickness.set(0.1)
fur.distribution.set(1)
fur.taper.set(0.8)
fur.bend.set(0.5)
fur.perArea.set(10.0)

It takes around 30 seconds to compile on my workstation (dual Xeon 2630 v4 with 128GB ram) and takes up about 14GB ram.

If we took this set up and assigned it to a grassy field of 100x100 meters instead, the geo compile would probably take 50 minutes and my machine would run out of memory.

I tried dabbling in the LOD settings but didn't see any major difference + I'm not sure how it handles an animated camera.

Linux
Maya 2016 Ext1 SP5
VRay #27809

[jgriffin]

Caching V-Ray fur is not currently possible. But 20 minutes sounds a bit too much. Could you send us a log so we can see what's going on?

Sure thing. Log is attached.

Rendered on my workstation: Mac Pro, 6 Core Xeon, 3.4GHz. 32GB RAM.

This render maxes out RAM and uses about 4GB of swap on the local SSD which is slowing things down slightly, I'm sure.

I've also played with LOD settings and lowering the distribution and can get compile times down but renders just don't look as good.

Thanks for looking into this!

Related question: log files used to be in /tmp on MacOS. Where are they now? I just copied the attached log from a terminal window.

[jgriffin]

So pretty much always ended up using VRayScatter instead.

Was not aware of this plugin... I'll check it out. Thanks!

[oglu]

has someone tried the world node in maya..?
https://vimeo.com/205891678

[Dan Andersen]

That looks very interesting, oglu. We're still on Maya 2016 though. Look forward to comparing it to VRayScatter once we switch to a newer version of Maya..

Mihail, did you have a chance to look at the log jgriffin attached and the little 'grass' script I posted?

[Mihail.Djurev]

That looks very interesting, oglu. We're still on Maya 2016 though. Look forward to comparing it to VRayScatter once we switch to a newer version of Maya..

Mihail, did you have a chance to look at the log jgriffin attached and the little 'grass' script I posted?

Yes, unfortunately, making it faster might take a while.