Unfortunately the last time I brought this up, this was the current stance.
So I don’t think we’ll see a per anything switch to stop traces that can’t exploit data already present in the gbuffer - like we’ve seen now with translucency.
A per shading model toggle would honestly be good enough for most cases I think.
But there are also some cases where regular, opaque geometry has a large mismatch between its screen trace vs lumen scene representation. I’m not sure what existing data within the opaque model could be readily used to determine whether to screen trace or not.
An example of this is when using certain features that don’t properly render into the surface cache. Distance field based effects, or camera vector based material effects don’t work in the lumen scene, but will work fine in the screen trace. This can lead to jarring differences in material appearance that are exposed at points where trace coverage ends. In these cases I’d want the option to skip the screen trace.
I just haven’t thought of a common thread that can isolate them without using that extra bit.