V-Ray Volume Grid

[hunter_williams]

Not sure if I should post this in here or in the regular V-Ray Maya area but here goes:

I was doing some research about the V-Ray Volume Grid and how it can load .aur (Phoenix files). I tried to load one in from my missile smoke simulation and nothing show up. I just get a box and that's it.

Am I missing a step?

[georgi.zhekov]

Which versions of Phoenix and V-Ray are you using?

Sometimes we make improvements to the aur format and if the aur file is saved by a newer Phoenix version compared to the V-Ray one, the Volume Grid won't be able to read the file.

Soo if you're using a Phoenix nightly build for example, but relatively older official V-Ray version, you won't be able to load the aura file in the Volume Grid until there is a new V-Ray version.

[georgi.zhekov]

Are you using V-Ray 5 by any chance?

[hunter_williams]

Georgi, I'm using the latest version of V-Ray 6 Maya but I am using a nightly from December 1st.

Funny thing is that I loaded in a sim into the Volume Grid on a file from a two weeks ago and that works but a sim I did last night doesn't.

So the reason last nights sim isn't showing because it was done with the Phoenix December 1st nightly?

[hunter_williams]

Also, I loaded an ocean sim from a couple of weeks ago and it shows up in the viewport but nothing renders.



I even tried assigning the water material that was used in the simulation scene and still nothing renders.

[georgi.zhekov]

Yes, we did some changes a few days ago so you will need a newer V-Ray build.

For the V-Ray Volume Grid to be able to load caches from the Phoenix nightlies you will need a nightly version of V-Ray as well. You can get the latest one from here - https://nightlies.chaos.com/main#/me...ble/stable_6.0
If you don't see them for some reason, drop a mail to the support people and they will help you out with the rights.

As for the ocean rendering inside of the Volume Grid you will have to adjust the settings a bit - first you will need to set the render mode in the Rendering rollout of the Volume Grid to one of the mesh modes - Cap Mesh or Ocean mesh (for example) if you're after an ocean look.
Then from the Surface channel option you will need to pick the Liquid/Temperature channel - this option tells which channel to meshed. Finally you will need to set the Surface level to 0.5 (this is the default value for liquids).

You can find more detailed info about what each option does here - https://docs.chaos.com/display/PHX4MAYA/Rendering

Please note that the V-Ray Volume Grid is not able to load particles such as splashes, foam and mist. If you wish to render these you will have to load the .aur file through a Phoenix simulator.

[hunter_williams]

Good to know. Thanks!

[hunter_williams]

Please note that the V-Ray Volume Grid is not able to load particles such as splashes, foam and mist. If you wish to render these you will have to load the .aur file through a Phoenix simulator.

Does that mean that I can't use the Chaos Cloud to render my ocean sim out?

[georgi.zhekov]

Chaos Cloud supports Phoenix nodes, so there shouldn't be any problem rendering ocean scenes. Still if you find any issues, please ping us.

As long as you use Phoenix and then you send over the scene to the Cloud - it should render properly.

[georgi.zhekov]

Hey, just a note that if you're using a Phoenix nightly build you won't be able to use the Chaos Cloud with it for now. We recently made some changes to the aur format and this is still to be updated on the Chaos Cloud.

If you use an official Phoenix build (from the chaos.com download section) it should work though.

[hunter_williams]

So if I wanted to setup a one or two computer render farm would I only need a V-Ray render license on those machines if my main machine has Phoenix installed?

[georgi.zhekov]

If you wish the two additional machines to be render workers only, you will need v-ray render licenses for them and Phoenix to be installed there (no need for an additional Phoenix license, it just needs to be installed). You can find a bit more on Distributed rendering here - https://docs.chaos.com/display/PHX4M...uted+Rendering

If you wish the other machines to be able to simulate as well - you will need at least a simulation license. You can find more about gui and sim licenses here - https://docs.chaos.com/display/PHX4M...ation+Licenses