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Re: When is principled shader coming out?

Posted: Tue Dec 11, 2018 5:39 am
by lacilaci
patrickawalz wrote: ↑Tue Dec 11, 2018 3:23 am the Disney material doesn't account for a lot of effects that can be present in a scene, for instance multiple scattering or irridescents. admittedly we don't account for the latter yet ourselves, but I'm hoping one of the open source papers released last year will be implemented as part of the new materials
Yes that's why I keep mentioning that instead some basic implementation or cycles copy, luxcore should have it's own and more robust ubermaterial that also follows principled material.
But like Dade said, it's a big topic. So I don't think it should be hurried up just for the sake of having any principled mat.

Re: When is principled shader coming out?

Posted: Wed Dec 12, 2018 3:16 am
by madcat117
Mutiple scattering and irridescents are only two factors and are not something that slows down princicpled shader especially considering it’s open source from Disney principled should have been added at same time when blender added to official build hurry up and add so I can finally use lux and use it without compromising my workflow that is the new standard for all CGI long gone is the days of gross and disgusting gloss and specular maps lmfao

Re: When is principled shader coming out?

Posted: Wed Dec 12, 2018 12:36 pm
by Racleborg
hurry up and add so I can finally use lux and use it without compromising my workflow
A little 'please' and 'thank you' could be added too!

Re: When is principled shader coming out?

Posted: Wed Dec 12, 2018 7:05 pm
by madcat117
they don't call me the madcat for no reason muahahahaha :twisted:

Re: When is principled shader coming out?

Posted: Wed Dec 12, 2018 8:23 pm
by marcatore
madcat117 wrote: ↑Wed Dec 12, 2018 7:05 pm they don't call me the madcat for no reason muahahahaha :twisted:
so we should happy that your nick is not something like "fuc***f_everyone_666" ? :)

Re: When is principled shader coming out?

Posted: Thu Dec 13, 2018 5:20 am
by madcat117
you mad bro?

Re: When is principled shader coming out?

Posted: Thu Dec 13, 2018 10:32 am
by B.Y.O.B.
1471388183675.png

Re: When is principled shader coming out?

Posted: Fri Jan 11, 2019 11:30 am
by epilectrolytics
Back to topic :)

From my experience in Blender/Cycles and Cheetah3D on the Mac side diffuse materials with PBR shaders render slower than with simple diffuse nodes.
That is because the principled shader has specular/glossy reflection at 50% by default and makes it diffuse via roughness and fresnel.
That's more realistic because in reality every material becomes reflective at grazing angles so the behaviour of the diffuse node no matter if Lambertian or Oren-Nayar is not physically correct.

So basically a principled shader always does blurred glossy reflections and thus produces caustic noise slowing down convergence.
Besides Clamping in Cycles there is a caustics filter to help with that called Filter Glossy.
This helps reflective and refractive caustic noise to converge faster by introducing biased blur which is not much noticeable when the material is rough anyways.

I would like very much to have this filter in LuxCore once the principled shader comes.
( Also it would help rendering caustics in PathOCL ;) )

Re: When is principled shader coming out?

Posted: Fri Jan 11, 2019 11:37 am
by lacilaci
epilectrolytics wrote: ↑Fri Jan 11, 2019 11:30 am
Besides Clamping in Cycles there is a caustics filter to help with that called Filter Glossy.
This helps reflective and refractive caustic noise to converge faster by introducing biased blur which is not much noticeable when the material is rough anyways.

I would like very much to have this filter in LuxCore once the principled shader comes.
( Also it would help rendering caustics in PathOCL ;) )
I would hope that secondary GI caching would help with that too. I think lightcache in vray has glossy ray filtering enabled by default.
On other hand, gi and rough reflections in cycles are insanely slow compared to luxcore (unless it's like very rough where you don't expect to read a silhouette of reflected object)