PBR Materials

[dobe]

Hi,

I'm trying to use poliigon textures right now. But it does not work.
What's wrong?

For example, the wood reflects too much!
The noise in the simple scene is also very strong although I use PhotonGI?
Is it possible to use Displacement(Map)?

Blendfile: https://drive.google.com/open?id=1afsnm ... BY4RuwJblU

Thanks for helping,

[marcatore]

Could you post also the material references ?

[dobe]

Wood: https://sketchfab.com/3d-models/wood-pl ... 74f31b8d7e
Concrete: https://sketchfab.com/3d-models/concret ... 903f515e49

I still have a Reflectionmap for each material. Is that needed for a good result?
octane and cycles do not need these textures!

[B.Y.O.B.]

One thing I found so far is that the normalmaps are set up wrong:

This is how it's done correctly (enable the "Normalmap" checkbox):

[B.Y.O.B.]

Next, why the cache is not helping:

Your roughness textures should have gamma 1.0 instead of gamma 2.2 set, because they are non-color data. I will try to make this easier in the future, I logged it as a github issue.

With gamma 2.2, this is how the cache debug view looks like.
Blue means that the cache is used for this pixel, red means that LuxCore falls back to brute force path tracing.
Basically, your roughness textures are too dark because of wrong gamma, and they make the material too glossy to be safely included in the cache.

After I fixed the gamma values of all roughness textures, this is the debug view:

And indeed, the cache is now helping.
Before, it took 60 seconds to render 200 samples. Now it takes 42 seconds for 200 samples, and the samples are of much higher quality so the image is almost noise-free.

Here is the fixed scene: https://drive.google.com/open?id=18cxO1 ... XZEuIG1UOH

[tayo6]

Next, why the cache is not helping:

Your roughness textures should have gamma 1.0 instead of gamma 2.2 set, because they are non-color data. I will try to make this easier in the future, I logged it as a github issue.

With gamma 2.2, this is how the cache debug view looks like.
Blue means that the cache is used for this pixel, red means that LuxCore falls back to brute force path tracing.
Basically, your roughness textures are too dark because of wrong gamma, and they make the material too glossy to be safely included in the cache.


debug_1.jpg


After I fixed the gamma values of all roughness textures, this is the debug view:


debug_2.jpg


And indeed, the cache is now helping.
Before, it took 60 seconds to render 200 samples. Now it takes 42 seconds for 200 samples, and the samples are of much higher quality so the image is almost noise-free.


fixed.jpg


Here is the fixed scene: https://drive.google.com/open?id=18cxO1 ... XZEuIG1UOH

Probably a 2 pages pdf on pbr setup in luxcore would be good. Thanks for the explanation of the relationship between roughness texture and gamma

[tayo6]

Wood: https://sketchfab.com/3d-models/wood-pl ... 74f31b8d7e
Concrete: https://sketchfab.com/3d-models/concret ... 903f515e49

I still have a Reflectionmap for each material. Is that needed for a good result?
octane and cycles do not need these textures!

I believe cycles doesn't really need reflection maps, yet it provides you with roughness node. Sometimes I connect textures of various types into the roughness node so I could get a unique reflection. Every material has reflection; it's either much or less

[dobe]

thx for help

[Sharlybg]

the floor look almost diffuse and it isn't automatically cacheable. it is a large surface that can give more performance if cacheable.

[dobe]

when will PBR be released? is that already planned?