Search found 405 matches

by CodeHD
Mon Nov 30, 2020 4:48 pm
Forum: Development
Topic: Disney BRDF material
Replies: 122
Views: 27632

Re: Disney BRDF material

Hi, just wanted to write down some thoughts on this that I have collected. Let me know what you think. 1) The topic of subsurface scattering could use a bit of consideration. There has been some talk about this again yesterday on Discord. It seems that it is important for artists to have SSS somehow...
by CodeHD
Fri Nov 27, 2020 2:52 pm
Forum: User Support
Topic: Specular reflection vs diffuse reflection.
Replies: 21
Views: 2124

Re: Specular reflection vs diffuse reflection.

To me the actual disney halo problem seems to be much simpler as it looks. The specular disney shader, as i see it implemented in Lux, seems to me a simple reflection layer following a fresnel function on top of diffuse reflection. There are two parts to this in the Disney shader: 1) There is indee...
by CodeHD
Fri Nov 27, 2020 12:57 pm
Forum: User Support
Topic: strange behaviour of homogeneous scattering volume
Replies: 17
Views: 2364

Re: strange behaviour of homogeneous scattering volume

Ok thanks for the additional info. Really don't know why I resented the idea that VDI would be the organisation in this context :lol: You would certainly have to play with the anisotropy of the volume scattering to get this effect. I could imagine one could even recreate this test setup, and write a...
by CodeHD
Thu Nov 26, 2020 8:50 pm
Forum: User Support
Topic: strange behaviour of homogeneous scattering volume
Replies: 17
Views: 2364

Re: strange behaviour of homogeneous scattering volume

Looking back at the data sheets, you might be right that there should be a diffuse volume component to the DF range, however it really looks small if any in you images... Do you have any more explicit data on what DF"23" and "8N" actually mean? I didn't find anything on their website. What is a "VDI...
by CodeHD
Wed Nov 25, 2020 3:43 pm
Forum: User Support
Topic: Specular reflection vs diffuse reflection.
Replies: 21
Views: 2124

Re: Specular reflection vs diffuse reflection.

What do you think or suggest? Sorry, forgot to respond again... My follow-up on Disney was here . That makes it a bit clearer what you're after, thanks. I'm looking at the updated Disney model now as you can see from the thread I linked. But it will probably a persistent question after that: Is the...
by CodeHD
Wed Nov 25, 2020 3:23 pm
Forum: User Support
Topic: How to cite LuxCoreRender?
Replies: 4
Views: 409

Re: How to cite LuxCoreRender?

There is no scientific- or conference paper about LuxCore if that's what you ask. Citing software in science generally is an "awkward" topic, partly because of that. As an alternative, you can also cite the GitHub repository, i.e. where the source-code is available, togther with a version number of ...
by CodeHD
Wed Nov 25, 2020 12:58 pm
Forum: Development
Topic: exr image output
Replies: 24
Views: 2744

Re: exr image output

Dade wrote:
Wed Nov 25, 2020 12:54 pm
It is not a linear space. A fixed scale can not fix the problem but I assume it is exactly what you are trying to show.
Yes, the factor 0.39 is specific to the LUXLINEAR tonemapper when comparing between gamma 1.0 and 2.2.
by CodeHD
Wed Nov 25, 2020 12:44 pm
Forum: Development
Topic: exr image output
Replies: 24
Views: 2744

Re: exr image output

No, the factor 0.39 was the ratio between the scale factors for different gamma, not the scale factor itself. At gamma 2.2, this evaluates to 2.465e-4.
by CodeHD
Wed Nov 25, 2020 12:09 pm
Forum: Development
Topic: exr image output
Replies: 24
Views: 2744

Re: exr image output

So to get the same result I have to map maximum value in exr to 1 and after this apply gamma correction. You might still not end up with exactly the same result as the LuxCore output, because LuxCore doesn't apply normalisation but a scaling factor that depends on gamma. (Normalisation doesn't real...
by CodeHD
Tue Nov 24, 2020 6:50 pm
Forum: Development
Topic: Disney BRDF material
Replies: 122
Views: 27632

Re: Disney BRDF material

Be careful, Cycles has extend Disney material in multiple way including using no GGX model for micro-facets (something never even vaguely mentioned by Disney people). Do you refer to the "Multiscatter - GGX" ? I ask this because I only see two models in the cycles principled shader, GGX and Multisc...