Dual Lobe Gloss?
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Can some kind soul explain Iray Dual Lobe Gloss to me in plain English please? I just can't understand what it is and what it is used for.
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Can some kind soul explain Iray Dual Lobe Gloss to me in plain English please? I just can't understand what it is and what it is used for.
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* Offers popcorn and sits next to, to wait ... *
Dual Lobe Specular? I treat it as an alternative to Glossy but with much finer control.
Specular - Gloss all the same to me and it is obvious that it is an alternative to the main Gloss Layer Weight but why is the real main Q. Seems like more work to set it up and more fiddling around to get it right.
As Uncle Ben said to Peter Parker, "...with great power comes more fiddling..."
The unreal documentation gives a good example.
https://docs.unrealengine.com/en-us/Resources/Showcases/DigitalHumans
Having 2 roughnesses and the ability to combine them on the same layer allows you to do things that the single Glossy can not do.
oh sweet thx, yeah that explains it well and not really needed for everything, really depends on the surface. That was big help prixat
Are you supposed to have two separate Glossiness or Roughness maps to make this work like in the Unreal example? I'm experimenting with it now, and while it gives nice control, it always seems like one of the Lobe values has no effect depending on how the Ratio is set.
Yes, you would need different roughness values to change the angles of where the effect will be seen. You may also need to adjust your viewing angle. In my simple diagram below, the lighter cone is "lobe 1" with a smaller roughness value and the darker is "lobe 2" with a larger one. From ViewPoint 1 (the orange wedge), you'd see a mixture of 1 and 2 depending on the weighting. From ViewPoint 2, you'd only see Lobe 2's effect.
Thanks, that's an interesting diagram. I thought maybe the 2nd lobe was showing reflections from other light sources or bounced light or something. Much appreciated.
Here's a little explanation I did for the diffeomorphic implementation. Please anyone feel free to add comments if you see anything that can be improved.
https://bitbucket.org/Diffeomorphic/import-daz/issues/321/dual-lobe-specularity-implementation-and
nice read thank you