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Poll: Metalness or Specular Reflectance (PBR)

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radiancef0rge Polycount Sponsor
No debate here please, just vote. I'm looking for average users for each workflow. Doesn't have to be in production, just what you use most often on an everyday basis. 


  • omar3d
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    omar3d polycounter lvl 5
    I couldn't tint spec color of non metals (Cloth, skin, etc) on stylized models with metalness. 
    Colored spec reflection isn't needed for most things realistic though (except fringe materials).

    Comparison above by @EarthQuake http://www.marmoset.co/toolbag/learn/pbr-conversion
    That second point in the cons of the metalness is why I will use metalness for a realistic model and instead spec color map for a stylized model.
    Can I still call the latter PBR because the diffuse map is shade-less with no light info?

  • ActionDawg
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    ActionDawg greentooth
    Metalness not by choice but because it's what UE4 supports and that's really the only engine I use personally, and for work (mobile apps) my packed metalness shader is cheaper memory-wise than spec would be.

    @omar3d yep even if your values are very unrealistic it's still all """PBR""" just not matching any real world thing. PBR being in super quotes because of the bajillion shortcuts taken for realtime that result in energy loss.

    Edit: A con inherent in both workflows that's worth repeating is that it's mathematically impossible to get a linear transition from a dielectric to a conductor without using layered materials. So rust to metal transitions will always lose energy if you're using a single spec or metallic material (Long time coming @radiancef0rge but I did eventually get around to making a unity program showing the difference).
  • poopipe
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    poopipe insane polycounter
    i prefer reflectance and it's also the model our engine uses but I've set up our substance library to support both models simultaneously with switchable outputs because I always assume the worst will happen..
  • alamonelf
    Some Obscure Workflow (Explain in Comments)
    We should use both languages  in the dielectric dialectic.
  • Joopson
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    Joopson Polycount Sponsor
    Personally, I wish all engines had the choice. But as it stands, I mostly use UE4, and that got me into metalness, where I remain.
  • gnoop
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    gnoop interpolator
    Have to work with metalness approach.   Personally would prefer   specular one .    Imo Metalness variant of PBR is most weird "improvement" I ever saw in gamedev.    It's like a disaster you should  adapt and survive .    Still fighting its artifacts and locked nature every day. 

    Those "illogical reflectance values" are usually pretty obvious .     And very subtle deviations  don't make perception of materials  less real while allow to work around some metalness approach oversimplification.
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