Full (Universal) GGX Range

[dubcat]

There are a lot of valid reasons here.

Right now 0 Gloss is more like 0.4 on the full range.

[Juraj]

This would be great.

I wonder how to keep consistency with past model though and scenes. Should have been done from get-go.

BTW, why does your example (I presume those are Vray renders then ?) look so different in color/total sheen as well, what material is that ? One without IOR ?

[dubcat]

Yes the one on the left is V-Ray, they are using the same settings. Same HDRI at same intensity.
It just looks darker because it's so damn rough, really nice for fabric stuff, you can see example in the other thread I linked to.



and here is the 0.4 V-Ray that kinda looks like Coronas 0.0



I don't know if it's possible, but what if Corona remapped the values based on the curve they are using. The first time you open a legacy scene. Kinda like what they did with bump value.

[Malor]

I wonder how to keep consistency with past model though and scenes. Should have been done from get-go.

People are offering to implement another legacy tickbox already.

Just from a lowly user's standpoint. I will happily rework all my glossiness maps on all my assets, if it will mean, that there's one industry standart for a roughness curve, and i don't have to tweak any downloaded mats anymore ever. Gotta admit, "industry standart"sounds great, heh?:) Not having to fake fabric falloff, sells the whole idea rather well i must say. Kudos dubcat.

[pokoy]

Fully agree. Also, having control over the tail parameter wouldn't be bad imo.
Since the legacy checkbox is there already, a transition shouldn't be too hard. I don't like the legacy idea but in this case it's useful.
Hopefully this would be the last change to the shading model, but like Juraj said this should've been done with full range right from the start.

[Juraj]

Ah, now I see, IOR=100 is what made the difference so obvious. Not sure metal can even get this rough ? Also I don't think velvet effect has anything to do with tail parameter, it's just as "fake" as diffuse falloff, only real way would be modelling millions of micro fibers scattering light at grazing angle, so what does it matter which fake is less fake :- ) ? Even UE4 shading model based on GGX which has full roughness scale has another node that basically just streamlines falloff effect to albedo/diffuse slot.

If the current model can seamlessly get under "legacy" again (merging/replacing current legacy ? The system would internally recognize both levels or the original would be forgone altogether ?) that would be nice.

[dubcat]

having control over the tail parameter wouldn't be bad imo.

That would be The Dream
Neil Blevins has a very nice article on why we would need this for realistic metals.

so what does it matter which fake is less fake :- ) ?

I'm not going to argue about that, but I'll take the GGX shader setup any day :)
You have more control with the falloff setup though, guess it depends on what fabric you are making.

[dubcat]

Quixel SUITE 2 and Megascans are right around the corner. Perfect time to trash the curve of evil :)

Stuff made with Megascans
https://www.artstation.com/artist/quixel

[Ondra]

done in 1.5