Ior to metalness conversion - VRayMtl

[jos_dasilvaneto]

Hello everyone,

I've been trying to come up with a conversion from reflection ior to metalness aiming to standardize my assets within the metallic/roughness workflow. I want to get rid of the high ior values used to emulate metalness in the past, replacing them by the standard ior (1.6) and adjusting the metalness value accordingly. I am trying to do this in two steps:

• Mapping the reflection ior to a flat metalness value: this means I assume there's a direct relationship or function with an unknown shape that can be used to compute it directly
• Scaling this flat value based on the reflection and diffuse colors

With that said, how diffuse and reflection colors actually act on defining how metallic a surface is given its reflection ior?


Best,
JN

[sirio76]

https://www.chaos.com/blog/understanding-metalness