[UE5] Is there now a specular workflow or still only metalness?
interpolator
Metalness has problems and generally less control than the specular workflow. Especially for gradual transition areas where you do not want to have a binary on/off for metal. Metalness workflow frequently results in artifacts on these borders (or areas that blend metalness with dirt etc). I don't know why UE5 would not also offer a specular workflow like for example Marmoset which offers metalness and specular workflows.
Replies
Use the specular Channel to control dielectric reflectance - that's what it's for.
I thought the specular channel was not really useful in UE4-UE5, and they advised against using it? Does UE5 have a full specular workflow that can completely replace the metalness workflow, and still create realistic metal surfaces?
the specular map works as it should - it represents 0 - 0.08f in a linear 0-1 scale
the default is 0.5 which covers most stuff, dropping that to around .37 gets you a half decent representation of scattery surfaces like skin.
these are all non metallic with specular values of 0.0, 0.35, 0.5 and 1.0 respectively. 1.0 is nonsense for normal real world materials but mathematically speaking it's fine
there's really no advantage to the specular workflow, it uses more texture memory and is still prone to the halo artefacts if you dont soften transitions between dielectrics and metals sensitively.
the output from the shader in both workflows is identical assuming equivalent inputs.
Id imagine they haven't allowed for a specular workflow because it has potential to massively increase shader build times and would break batching of materials at render time.
Thanks! What's the best way to reduce 'halo artifacts'? When I add for example dirt on top of the metal, there will inherently be a soft transition between metal and another material. Dark dirt on metal will look far too light because of this even if I set it almost to black Albedo and high roughness.
I tried a lot of different settings, but the Specular workflow in Marmoset results in far better quality and fewer artifacts when blending metals with other surfaces than the metalness workflow in Marmoset.
Also, the Unreal Engine metalness workflow has the same problems as the metalness workflow in Marmoset. But, the specular workflow from Marmoset creates superior results for soft blending metal with other materials.
Does anyone know if UE5 is planning to add colored specular instead of metalness at some point? How do you achieve AO dirt on metal for example in the metalness workflow? As far as I can tell this always results in some sort of washed-out values instead of dark AO dirt. I just don't understand why the colored specular PBR workflow isn't an option in UE.
Is 'Strata' the solution?
https://dev.epicgames.com/community/learning/courses/92D/unreal-engine-strata-materials/vEaW/unreal-engine-strata-what-is-strata
only in the sense that any layered material system is the solution - which is to say it'll fix lots of problems if you're prepared to pay for it