V-Ray 3.0 For 3ds Max Updates

[^Lele^]

On the subject of the disney principled BRDF, i took to scripting a version of it as close to the one on the paper as i can muster (of course, only working for everyone at the time of sp1) which works for vray.
It has a few caveats, but they are quite minor.
Work isn't finished yet, but some early tests while building looked promising enough to show.
The shader is the same scripted one for the three sculptures, it took a handful of second to author each variant, using only very very few clear controls.
Aside from the obvious (raytraced) SSS, everything else is reflective microfacet GTR, there is nothing else but that.

[Nicinus]

and a link to the chief paper in matters of BRDFs at this moment in time, from Disney, from which pretty much everyone is drawing inspiration or straight-out code (see fig.18 for the BRDFs gamma comparison.)

https://disney-animation.s3.amazonaw...f_notes_v2.pdf

Great read! Understood it all. Super simple actually.

[wyszolmirski]

On the subject of the disney principled BRDF, i took to scripting a version of it as close to the one on the paper as i can muster (of course, only working for everyone at the time of sp1) which works for vray.
It has a few caveats, but they are quite minor.
Work isn't finished yet, but some early tests while building looked promising enough to show.
The shader is the same scripted one for the three sculptures, it took a handful of second to author each variant, using only very very few clear controls.
Aside from the obvious (raytraced) SSS, everything else is reflective microfacet GTR, there is nothing else but that.

[ATTACH=CONFIG]21723[/ATTACH]

Thats very cool. I'm giving it a try now.

[^Lele^]

you will need a nightly build for that (in max at least)...

[wyszolmirski]

you will need a nightly build for that (in max at least)...

I know . Did it in newer builds name changed from GGX to GTR after adding tail parameter ? The one I have is still GGX and tail.

Anyway after first tests and from visual standpoint I like the most simple specular (tail 2.0) + diffuse (tail 10, and very low gloss) + just a bit of sheen. Also I can see using Sheen + Diffuse quite a lot actually.

Best,

Tomasz

[^Lele^]

Here are the layers, at their default settings, for the material i scripted (will continue in the next posts).
in order, from left to right (representing the corresponding layering order in the material from bottom to top): SSS, Refraction, Sheen (A.K.A. retro-reflection, or a very pronounced rim-line)

[^Lele^]

Layer 4: Diffuse (with variable roughness and IoR, to control exactly the look. here's made to resemble the standard diffuse material.), layer 5: metallic (with the ability to produce a cheap, fast thincoat-like effect, and to change reflection contrast), and the standard Isotropic Specular (quite broad here. both glossiness and contrast -the tail parameter- for the lobe can be modified.) for Layer 6.

[^Lele^]

Anisotropic specular (with the same iso spec parameters, plus all those needed for the aniso shape), gunMetal (to be tried on a gun! ^^) is just a special case of lobe-to-tail ratio which seems to work really well for stuff like the metallic alloys used in weapon making. Emissive comes last, top of the 9-layers pile.

[wyszolmirski]

Very interesting. Is the script going to create base VRayBlend shader as starting point for the artist ? Or will there be some more complex math to it and shader creation and modification will be left almost fully for the script ?

[^Lele^]

This is an earlier UI screenshot, where the texturing, and presets management rollouts were still amiss.
Would you like/be able, to work with such a minimalistic interface, provided you could dig deeper later if you so wished? (See the "Extract Material Copy" button, which allows for de-encapsulation of the underlying blend and standard vray materials, so that you can treat it as a standard shader with the full set of usual controls)
Or would you still prefer to go and build away from scratch, and the building blocks, each time?
It's a personal curiosity, mind you, as i know i would use this type of approach for most of my basic setups (particularly with the insta-save presets, iteration is a breeze.), and only go fiddle with the full blown material setup if i needed to (say, to texture a material parameter for which the brdf mixer UI provided no control), but i'm not sure of what others think of it...

[wyszolmirski]

That's interesting approach. I personally would prefer some simple starting setup that I can just import and use. But my shaders usually are very complex on the "map" side. That said, I think your approach will be very appealing for quick setups, also very good for less experienced artists that don't necessarily have to understand every single parameter.

After taking an closer look at the behavior of tail in GGX I still would try to go with single VRayMtl without blending if possible. Just to save a bit of render time. I would need to control tail with map though.

Also what's the reason for using such a high IoR for Diffuse layer ? I just find that keeping it below 2 works well in most cases, but I may be wrong.

Best,

Tomasz

[thomaskc]

Uh I haven't heard anything about this upcoming service pack!?
Is there a list or unofficial list of "promised / expected" features or changes for this? Sounds awesome!

Thanks

[^Lele^]

Well, it renders prettier, and faster.
Much, prettier; much, faster: much wow. ^^
Like so:

[bardo]

the dog facial expression is wonderful... it saw the new features of the service pack?

[thomaskc]

Well, it renders prettier, and faster.
Much, prettier; much, faster: much wow. ^^
Like so:
[ATTACH=CONFIG]21881[/ATTACH]

They all say that.. but very little proof so far :P