randomwalk SSS

[LeoYfver]

It would be really nice to have random walk SSS in vray. Here is the implementation in blender https://developer.blender.org/D3054#72261

[Muhammed_Hamed]

The volume scatter material in Max uses Random walk SSS.. It is very easy to setup and gives impressive results
Hopefully Chaos Group implements this material in Vray for Maya. You will find countless threads here asking about this material
You will find other threads on Blender/Modo/C4D forums as well.

[vlado]

Yes, it's coming up in the nightly builds for Maya.

Best regards,
Vlado

[Paul Oblomov]

OMG. Rly ? Can you plz add gradient mapping abilities, so volume can falloff at the edges ? That will close atmosphere quest for me. Plz plz plz.

[vlado]

OMG. Rly ? Can you plz add gradient mapping abilities, so volume can falloff at the edges ? That will close atmosphere quest for me. Plz plz plz.

This is more complicated, although one of the guys recently was doing some research related to that.

Best regards,
Vlado

[jasonhuang1115]

vlado is VraysSatterVolume added to Maya nightly builds now? I can only find "BRDFScatterVolume" from V-Ray plugins which seems to be the one but I am not 100% positive. I am running the official Next update 1 build.

[vlado]

You will have to go through the BRDFScatterVolume for now, yes. Let me know if you have any questions about it.

Best regards,
Vlado

[jasonhuang1115]

vlado Would this node be a better candidate for rendering sss for skin over the VrayAlsurface?

If yes, is it a good approach to use it as a base and blend a couple of spec lobes as coat materials using VrayMtl in a VrayBlendMtl?

The idea is to render skin with random-walk sss and two spec lobes while still being physically-plausible/energy conserved.

[vlado]

vlado Would this node be a better candidate for rendering sss for skin over the VrayAlsurface?

The scatter volume is more physically accurate but may require 20-25 volume bounces to look ok, which may take a while to render. It also has more strict requirements to the base mesh (i.e. it must be a single closed volume without self-intersections). From my experience, it is mostly useful for objects that have small translucent details. For skin specifically, I'm not sure you will be able to tell the difference between the scatter volume and the alSurface model in most cases - but I would advise you to experiment.

If yes, is it a good approach to use it as a base and blend a couple of spec lobes as coat materials using VrayMtl in a VrayBlendMtl?

This will work well enough for now until VRayScatterVolume makes its way to VRayMtl itself along with a second specular lobe.

Best regards,
Vlado