Chaos scatter - missing scatter instances.

[sylk]

Hi, we are experiencing a problem with Chaos scatter on our renderfarm. 3dsmax 2024.2, V-Ray 6 update 1.2, Chaos scatter v.4 (release candidate 0).

In this case we have a scene with a single VrayMesh scattered about 5000 times on some cylinders.

When submitting to our farm (RoyalRender) the rendernodes each get roughly 10 frames assigned to them. The first frame in each assigned sequence is missing the instances. The rest are perfect.

It feels like the render starts before the instances are fully loaded? The rendernodes keeps the scene open between frames.

We load V-Ray and Chaos scatter as application plugins from a network share for the rendernodes.


If anyone has a hint of what is going wrong it would be much appreciated!


Cheers!
/Andreas

[vladimir_krastev]

Hi, thanks for posting. What happens if you send only the missing frames to the farm as single frames? Have you tried to render the animation on the remote machines without RoyalRender?
How is RoyalRender managing the jobs - opens a 3ds Max node? Do you have error messages in your V-Ray logs?

[Joelaff]

One possibility: See this post. Add .vrmesh to the list if you use the list. Curious if this helps.

[sylk]

Hi, thanks for your replies.


vladimir_krastev

We have our workstations on the farm as well and we get the same result on those machines when they render through Royalrender.


RoyalRender renders with max as a service, no ui. On all clients, workstation or rendernode.


No Errors in the Royalrender/V-Ray logs.


Here are some of the env.vars we set when Royalrender launches Max:

VRAY_FOR_3DSMAX2024_MAIN: "//share/ApplicationPlugins/VRay3dsMax2024/bin"
VRAY_FOR_3DSMAX2024_PLUGINS: "//share/ApplicationPlugins/VRay3dsMax2024/bin/plugins"
VRAY_MDL_PATH_3DSMAX2024: "//share/ApplicationPlugins/VRay3dsMax2024/mdl"
VRAY_OSL_PATH_3DSMAX2024: "//share/ApplicationPlugins/VRay3dsMax2024/opensl"
ADSK_APPLICATION_PLUGINS: "//share/ApplicationPlugins" -- chaosscatter and vray are located in this folder

Does the order we set them in matter?


We made a hacky workaround for now where we made a postload-script that renders a 10x10px no lights frame before the actual frame gets rendered. That fixes it for us. Not a great solution though... One interesting thing was that we had to save that dummy render as well. otherwise it didn't work.


Joelaff

To rule out the .vrmesh as the culprit we sent a render with a freshly created teapot as scatter object. We got the same result. First frames in each sequence had no scattered instances. I guess that rules out your potential solution?

[vladimir_krastev]

Hi, after deeper investigation it turned out we have the same issue logged internally as a bug (VMAX-13515).

max as a service, no ui

Our automated tests run the same way and this bug was spotted and reported by the QA. I will now link the thread to it and raise the priority.

[vladimir_krastev]

Hi again. Would you mind sharing what processors you are using on your farm and workstations. We have a suspicion it could be an issue with specific processors only.
If you prefer to share this information privately, please open a ticket (preferable) or as a private message using the forum platform. If you use a ticket please add a link to this thread for reference.

[sylk]

Ok, thanks!

I opened a support ticket.

/Andreas

[vladimir_krastev]

Thanks for the assistance. We highly appreciate it