Best way to render wetting particles with Redshift

[cam.crichton]

I have some fluid sims exported as alembics and looking very nice rendered in Redshift. I would like to make use of the wetting particles and I'm looking for recommendations as to the best way to do this.


Maya 2023.3, Phoenix 5.1 and Redshift 3.5.09

[Svetlin.Nikolov]

Hey,

The standard method in Phoenix is to use the Phoenix Particle Texture to read the positions of the particles and use that as a mask for blending between a wet and a dry material. Here is an example at the bottom of this page setup: https://docs.chaos.com/display/PHX4M...articleTexture

However, I strongly suspect that this might not work in Redshift as the Particle Texture might not be supported.

Another method I can think of is meshing the wetmap particles into a separate mesh that you have a separate material. It's also happening using a particle texture, but it would happen in the viewport and eventually you should be able to convert the mesh into Maya Mesh mode from the Simulator's rendering menu, allowing it to render in Redshift. Here is the technique for creating the mesh from the particles - the video is in Max, but the same principle should work in Maya: https://youtu.be/6J5XjLeZQyo
And a related video as well: https://youtu.be/ETl6CjvWFDc

The mesh produced from the particles might probably need some refining, so please also check this page for different things you could do to smooth it out: https://docs.chaos.com/display/PHX4M...+and+Smoothing

I hope this helps get you in the right direction!

[cam.crichton]

Doesn't appear to be any way to select the particle system in Maya


I connected it in the Node editor but it's not working as far as I can tell

[cam.crichton]

I guess I can just duplicate the grid and set the preview to the wetting particles - that'll probably work.

[georgi.zhekov]

Ah, when you press the Edit Particle System button in the Particle texture you can connect the set for the Particle texture to the Wetmap particle set like this.

Note that only 1 particle system needs to be selected so make sure to pick only the Wetmap or any other one you wish to use.

[cam.crichton]

I am trying to connect the particleTexture to the surface texture in the Simulator but it just freezes every time I turn on the mesh.

It does this in my scene and in the waterfall preset in a new scene.

[cam.crichton]

If I can't specify another channel (like splash or mist) in the texture I can't get anything out of Phoenix except the liquid/temperature mesh. If I have to make the splash and mist separately I may as well make the whole thing in another package.

Right now I'm tossing up whether to use tyFlow in Max or get Vray for Maya and hope that I can render the Phoenix particles that way.

[georgi.zhekov]

Hey,

Seems to be working on our side with the waterfall preset. Here are my steps to make it work - https://youtu.be/PpAG8PMvSEI

Can you tell us the exact steps to make it freeze?

Also can you try using the latest Phoenix 5.20 build from the Chaos website, just in case it is something we fixed along the way?

Thanks!

[cam.crichton]

Sure I'll update to the latest, currently using 5.1.

At 32 seconds in the video is when Maya freezes - adding the shader into the texture field.

Assuming everything after that will be fine as it is the same for how I am rendering the liquid.

Is there a way to actually render them as particles?

[georgi.zhekov]

Yes, you can. In the Outliner go to Display > disable the checkbox for DAG objects only.

Then in the Outliner you should be able to see the Phoenix particle systems. Select the one you wish to use and while it is selected you will have an option in the Attribute editor to use this system to create Maya nParticles - https://docs.chaos.com/display/PHX4M...Particle+Group

Then you can render these as you would render any other nParticle systems in Maya.

[cam.crichton]

Thank you. Updated to 5.2 and the freeze still occurs at the same step.

[georgi.zhekov]

Can you do a screen-record by any chance of your steps? Maybe I'm doing something little different over here?

Also can you set the Phoenix log verbosity to "Debug" from the top PhoenixFD menu > Phoenix Preferences and try to break it again.
Then can you send over the log file? In the Phoenix preferences menu there is button to open the log file location.

Thanks!

[cam.crichton]

can't upload mp4!

[cam.crichton]

https://drive.google.com/file/d/1Rpj...ew?usp=sharing

[cam.crichton]

I have tried nParticles about a dozen times. It only worked once but was completely unresponsive at render time, I had to force quit and it has never worked since. When I select the Splashes and "create nParticles" it still creates the nodes but nothing is visible.


edit:
I had some success setting up the waterfall with nParticles - but after closing the file and reopening, the particles don't render anymore