Disney BRDF material

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B.Y.O.B.
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Re: Disney BRDF material

Post by B.Y.O.B. »

epilectrolytics wrote: Thu Jun 06, 2019 3:07 pm I was not able to tweak the parameters so that both look the same, roughness works totally different between the two.
This is intended, the disney shader uses a more artist-friendly roughness (I like it a lot).
But you can convert between the two:
https://docs.blender.org/manual/en/dev/render/shaders/nodes/types/shaders/principled.html wrote:When converting from the older Glossy BSDF node, use the square root of the original value.
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Re: Disney BRDF material

Post by epilectrolytics »

Thanks for the tip, this will help with converting old glossy to new Disney materials!
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Re: Disney BRDF material

Post by lacilaci »

How much different is it from luxcore materials, in laymans terms do we "loose realistic look" with this?

I'm kinda getting used to luxcore materials, though I would appreciate a monster ubermaterial that can go from glass to metal to plastic to paper or leaf with handful of sliders.
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Re: Disney BRDF material

Post by epilectrolytics »

lacilaci wrote: Thu Jun 06, 2019 4:41 pm How much different is it from luxcore materials, in laymans terms do we "loose realistic look" with this?
I'd say it looks slightly better, theoretically it should because of GGX microfacet model and other goodies,
but you should test yourself now that it is accessible from Blender (latest master).
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Re: Disney BRDF material

Post by sarmath »

Hi there. Just updated to latest builds but cant see Disney material exposed anywhere? Any ideas why?
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Re: Disney BRDF material

Post by Dade »

Side note

There is a theoretical advantage in using disney BRDF for all materials in a scene when rendering on GPUs: lack of threads divergence. In theory GPUs while evaluate a lot faster a scene where each hit point requires to run the same material code (threads can run the code in parallel instead of having to serialize the execution of divergent code).

It would be interesting to do some test with a scene using many LuxCore materials and the same scene using only the LuxCore Disney material to check if there is a real advantage on GPUs or not.
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Re: Disney BRDF material

Post by Dade »

sarmath wrote: Fri Jun 07, 2019 2:18 pm Hi there. Just updated to latest builds but cant see Disney material exposed anywhere? Any ideas why?
You need also to update BlendLuxCore, have you ?
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Re: Disney BRDF material

Post by Dade »

Dade wrote: Fri Jun 07, 2019 2:24 pm
sarmath wrote: Fri Jun 07, 2019 2:18 pm Hi there. Just updated to latest builds but cant see Disney material exposed anywhere? Any ideas why?
You need also to update BlendLuxCore, have you ?
This: https://wiki.luxcorerender.org/BlendLux ... _to_Update
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Re: Disney BRDF material

Post by marcatore »

Dade wrote: Fri Jun 07, 2019 2:24 pm Side note

There is a theoretical advantage in using disney BRDF for all materials in a scene when rendering on GPUs: lack of threads divergence. In theory GPUs while evaluate a lot faster a scene where each hit point requires to run the same material code (threads can run the code in parallel instead of having to serialize the execution of divergent code).

It would be interesting to do some test with a scene using many LuxCore materials and the same scene using only the LuxCore Disney material to check if there is a real advantage on GPUs or not.
Interesting...it could be a win win situation...
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Re: Disney BRDF material

Post by epilectrolytics »

Dade wrote: Fri Jun 07, 2019 2:25 pm
Dade wrote: Fri Jun 07, 2019 2:24 pm
sarmath wrote: Fri Jun 07, 2019 2:18 pm Hi there. Just updated to latest builds but cant see Disney material exposed anywhere? Any ideas why?
You need also to update BlendLuxCore, have you ?
This: https://wiki.luxcorerender.org/BlendLux ... _to_Update
I think that will only install the latest beta but not the latest commits.
B.Y.O.B. said there is a special Blender 2.79 maintenance branch in which the Disney shader is exposed.
This has to be opened in Github and downloaded from there, then used to manually overwrite the Blender add-on files on the user's harddisk before putting the latest LuxCore files in the bin directory there.
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