Peter Kutz

Hi @sharktacos , I agree that being able to make dark fuzz would be very useful. I also raised this concern a while back and we actually already included this...

@portsmouth All of your reasoning makes sense. Thanks for thinking about this in depth. I have a few questions about the details of your proposals. > It could be argued...

> Technically the metal_weight is needed to be able to kill the metal lobe completely to zero (as mentioned in a https://github.com/AcademySoftwareFoundation/OpenPBR/issues/140#issuecomment-2023817200above). As without it, setting both metal_color and metal_edge_tint...

This was first suggested and derived by @Reedbeta : Using the syntax from the [ASM technical document](https://helpx.adobe.com/substance-3d-general/adobe-standard-material/asm-technical-documentation.html), given `F_F82Tint(θ) = r + (1 − r)(1 − cosθ)⁵ − bcosθ(1 −...

The Disney BSDF notes @fpsunflower mentioned are from the 2015 Physically Based Shading course and linked from here: https://blog.selfshadow.com/publications/s2015-shading-course/#course_content Attached is the relevant part of the course notes. While it...

Last year, @portsmouth and I also discussed a similar concept in the context of polarization. Here's a recap of that, including diagrams illustrating the scaling. Like @fpsunflower mentioned, `F(n_t /...

Here's another example, plotted in Mathematica, illustrating that the Fresnel curve for going from high to low IOR can be transformed to match the Fresnel curve for going from low...

In practice, the key is that, as @fpsunflower described, when going from high IOR to low IOR, you don't evaluate the Fresnel equations directly. You first calculate the refraction angle...

Nice analysis and investigation @portsmouth ! Based on all of the considerations, "Proposal II: Decoupled IORs" does seem like the best approach. It makes sense intuitively that this approach conserves...

Hi @portsmouth , Thanks for working on this improvement. Since you've iterated on this multiple times, I want to make sure I understand the problem that this is trying to...