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PBR workflow

zombie420
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zombie420 polycounter lvl 10
I'm trying out the PBR workflow but I'm having trouble adopting it. More precisely, what maps do I select from Quixel's Suite and what inputs do they correspond to in Toolbag 2?

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  • JustMeSR
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    JustMeSR polycounter lvl 4
    zombie420 wrote: »
    ...what maps do I select from Quixel's Suite...

    All of them

    zombie420 wrote: »
    ...and what inputs do they correspond to in Toolbag 2?

    Aren't they the same? Albedo to Albedo, normal to normal...
  • zombie420
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    zombie420 polycounter lvl 10
    Perhaps I've explained this wrong. Albedo and normal? Those understand, no problem. But Quixel's Suite has tons of maps, and plenty are not relevant at all... So I'm positive I don't need "all of them." And Quixel's "albedo for metalness"? Not sure what that one is. I'm doing a hard surface gun with some metals, so it might be useful, but a quick test shows me that the regular albedo is closer to the results I'm looking for.

    In conjunction with alebdo and normal, some people seem to use different maps for different PBR workflows. Stevston89's dagger used spec and gloss/ roughness in a PBR workflow. The PBR pipeline on Marmoset's wiki references microsurface and reflectivity; two maps that are absent from Quixel's Suite. Joeri Vromman uses reflectance and roughness maps on his killer firearms (absent on Quixel's Suite) and Clinton Crumpler puts his roughness/ metalness and ao maps in a single map (which is smart, but again the first two maps are absent from Quixel's Suite).

    So I suppose my original question can be restated as "Does Quixel support metalness and roughness maps? And if so, how do I use them? And after that, where do I plug them into Toolbag 2?"
  • EarthQuake
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    I would start with these tutorials to understand the differences between the various inputs (pbr does not necessarily require metalness or roughness maps, this varies depending on target engine):

    http://www.marmoset.co/toolbag/learn/pbr-theory
    http://www.marmoset.co/toolbag/learn/pbr-practice

    Now, to load a metalness map in TB2, swap the reflectivity from specular map to metalness. To load a roughness map, load it in the gloss slot and click the invert box. If you want the GGX shader model (like UE4) swap the reflection model from blinn-phong to GGX. If you want all of this, load the Unreal 4 material preset from the material presets dropdown.

    For dDo, simply enable metalness as one of your map types, and I think also "albedo for metalness" is what its called, and disable specular. I think there is a roughness option too, if not, simply add a curves layer in PS to the top of your gloss map to invert it, or invert it after you're finished with the texture if you want to preview with 3Do. dDo doesn't support GGX calibration yet but it should in the next update.
  • throttlekitty
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    Specular = Reflectivity.
    Gloss = Microsurface and Roughness.

    Your average asset would use Albedo, Reflectivity, Microsurface and Normal. All the other map types get into app-specific requirements for each main type.

    Albedo for Metalness refers to the metalness workflow, where Albedo and Specular do the same job, while Metalness is masking metal vs non-metal.
  • EarthQuake
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    When using the metalness workflow, the albedo map represents the albedo values for non-metals, and reflectivity values for metals, so you need to use the albedo for metalness map type so dDo knows what to do with the texture content.
  • throttlekitty
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    Oh, that makes much more sense, thanks! Guess I kind of glossed that over when reading up on that.
  • CharlieD
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    CharlieD polycounter lvl 11
    Hey guys, I'm just now finally jumping onto the PBR train. I've been watching videos and reading tutorials. The more they describe the reflectivity map, it basically sounds just like making a black and white specular map. Is this correct? Also, in what cases would you use the metalness method?
  • ZacD
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    ZacD ngon master
    A lot of game engines, like UE4, use metalness because it is cheaper, and the results are very similar.

    Reflectivity maps are much less noisy when compared to traditional specular textures. They are basically solid color separating different materials, the gloss/microsurface/roughness is going to have all of the noise, detail, and variation.
  • CharlieD
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    CharlieD polycounter lvl 11
    Ah, wow, that really just cleared everything up for me. Thanks! Another quick question though, do people still use spec maps? I still see people mention spec maps here and there.
  • Fogbrain
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    Fogbrain polycounter lvl 5
    I also have a quick question for you guys, since there are 2 different workflows for PBR, the metalness and the specular/reflectivity. What if you are working on an object that isn't metal anywhere. Would the metalness workflow still be applicable or would you have to use the other workflow? I've only used metalness so far and it makes the most sense to me.
  • JordanN
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    JordanN interpolator
    CharlieD wrote: »
    Ah, wow, that really just cleared everything up for me. Thanks! Another quick question though, do people still use spec maps? I still see people mention spec maps here and there.

    Spec maps have no effect on metals. Usually a single number value is plugged in into the specular node if you want to change something (although most times it's just left alone).
    Fogbrain wrote: »
    I also have a quick question for you guys, since there are 2 different workflows for PBR, the metalness and the specular/reflectivity. What if you are working on an object that isn't metal anywhere. Would the metalness workflow still be applicable or would you have to use the other workflow? I've only used metalness so far and it makes the most sense to me.
    The opposite of metal in UE4 is the 0 value. So you use that, and continue your roughness/normal/AO workflow as usual.
  • EarthQuake
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    JordanN wrote: »
    Spec maps have no effect on metals. Usually a single number value is plugged in into the specular node if you want to change something (although most times it's just left alone).

    Its important to note that the "specular" input in UE4 isn't a specular input at all. Its more like a cavity map. Its really confusing, but don't even think of that as specular as its something completely different.

    People do still use specular intensity maps, but not in UE4, and generally not along with the metalness workflow, its usually an either or situation.
    Fogbrain wrote: »
    I also have a quick question for you guys, since there are 2 different workflows for PBR, the metalness and the specular/reflectivity. What if you are working on an object that isn't metal anywhere. Would the metalness workflow still be applicable or would you have to use the other workflow? I've only used metalness so far and it makes the most sense to me.

    Generally you will not have a choice, your engine will use either a full color spec map or the metalness map workflow, so you do whatever your engine requires. If there are no metallic areas, you can you a constant input of 0 for your shader and skip the texture.
  • Millenia
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    Millenia polycount sponsor
    e: nvm, delete me
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