We find that there’s no visual change when using Substrate’s second roughness when the Blendable GBuffer format is enabled. Looking at the slab complexity and material graph substrate stats, we see that the material topology preview correctly updates with 2Ro, the per pixel byte count increases and the slab complexity shifts to single.
[Image Removed]
Looking at the material properties, we see that the material mode is still marked as Simple.
[Image Removed]
We wanted to confirm if using second roughness should lead to a visual change with future updates or if it will be marked as disabled, like with the glints slab pins.
Yes that is as designed: because what legacy does not support is not supported by the blendable gbuffer. Which is using the legacy gbuffer representation. Blendable gbuffer won’t support colored specular, SSS using MFP, Glint or layering for isntance.
I have a task to have the second roughness accounted for with legacy gbuffer, but it will only be a blend of roughness leading to a single specular lobe.
Adaptive GBuffer must be use for advanced look and use cases at a cost.