WIP - melMass

[melMass]

Hi all,

I recently started using LuxCore and I love it.
In this thread, I will be posting WIP images while discovering Lux.

Car Paint
The settings of the CarPaint shader are still quite obscure to me so in the next few days I'm planning to do a lot of cars renders that I'll post here.

Pink Golf II


And the shader in case someone realizes I'm doing something stupid

[Dade]

The settings of the CarPaint shader are still quite obscure

It is mostly a 3 layers material where you can set the properties of each layer.

[melMass]

Oh, I missed that point thanks!

So are they stacked in a specific order? 3 is the "most out" layer?

I'm I right to assume that I can isolate each of them by setting the others to black then?

EDIT: also the presets do not seem to work on my end (Mac OSX Mojave in Blender 2.81)

[Dade]

So are they stacked in a specific order? 3 is the "most out" layer?

I'm I right to assume that I can isolate each of them by setting the others to black then?

Yes, if you check the code (https://github.com/LuxCoreRender/LuxCor ... nt.cpp#L71) you will see the 3 layers are summed and setting the specular value to black will disable a layer.

EDIT: also the presets do not seem to work on my end (Mac OSX Mojave in Blender 2.81)

They should, what version are you using ?

[Sharlybg]

Sorry for pointing that out but there is a mess here about carpaint :

viewtopic.php?f=4&t=2004

[kintuX]

From the looks, make sure you don't have image overexposed.

[melMass]

Thanks Dave!
The preset issue might be related to Sharlybg's thread, I'll check it further.

From the looks, make sure you don't have image overexposed.

Definitely, I'm not sure of the reason or the way to have the same global light without overexposing, if I expose it right it's very dark, I'm using ACES which might not be fully compatible with LuxCore...

[lacilaci]

I would rather maybe try mixing 2 disney materials and try to construct your carpaint that way rather than this dedicated shader... Doesn't seem too useful to me

[melMass]

I would rather maybe try mixing 2 Disney materials and try to construct your car paint that way rather than this dedicated shader... Doesn't seem too useful to me

Thanks for the advice I had not tried the Disney shader yet! It does have all the components I need.
About my overexposing issue, I realize that the shader's components of the car paint are summed not averaged.

Does that mean that all the R's summed should equal 1?

[Dade]

Does that mean that all the R's summed should equal 1?

It is probably even worse because there is 1 diffuse layer and 3 glossy layers so you have to balance all of them (including the diffuse layer). If you check the Glossy2 material code, you will see it has automatic energy conservation between diffuse and glossy layer. Carpaint is missing it.

Carpaint has its root in something written more than 10 years ago, I assume it was originally intended to be used with the with one of the pre-computed presets: https://github.com/LuxCoreRender/LuxCor ... t.cpp#L463