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Zbrush to Substance Painter Issue

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BucketOfNuggets polycounter lvl 6
HI all, got a bit of an issue. 

I am trying to export my Highpoly from Zbrush straight in to Substance Painter to bake on my Lows and I am having some issues. Below is what comes out. I think it might be a scale issue but when I import it in to Maya, the highs match up perfect with the lows. I would normally bring the highs in to maya to rename and export but I am using Maya LT at home and the output limit is a joke.
I'm doing a bunch of rocks at once, maybe that is the issue? I tried exporting the High pieces one at a time and still the same result. in substance I have different materials for each low piece, so there is no overlapping uvs.

This is the export settings in Zbrush, which come in to Maya fine. I am working in meters in Maya. When I adjust the scale though to 1 it is too small even though that should mean it is working 1:1? When I move it to 1 than scale it back up again to 10000 it starts coming back in to maya at a smaller scale.  I've also tried the fbx exporter and while it still all lines up in maya it still has the same issue in Substance.



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  • kanga
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    kanga quad damage
    No idea what is going on, but did you use the FBX exporter from zBrush? In zBrush 4R8 and zBrush 2018 my FBX exporter looks different. Maybe something to try.
  • sprunghunt
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    sprunghunt polycounter
    I also use maya LT 

    I've had problems with the offsets in zbrush causing the mesh to not be in the same spot as the OBJ lowpoly I import to Maya - I'd set the offset to zero before exporting. 

    I personally set the scale to 16. This seems like a good size when I import it into maya - but it depends on how big the meshes are in zbrush. Turn on the floor grid to see how big they are. Or append a box polytool for scale.

    Also you can try using decimation master to make a  version of your  hipoly that you can import to check size and location. 
  • Steamy_Steve
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    Steamy_Steve triangle
    Some most obvious "did you....?" from someone who's been banging his head on normal maps baking for the last few months:
    .- did you export high and low in the same format? OBJs and FBXs seem to export with different scales and axis directions (at least in Blender)
    -. did you make low-polys by ZRemesh-ing in ZBrush or by hand in Maya? if it's the latter case, be sure to freeze transformations in Maya and then re-check low/high meshes overlapping (use subdiv lvl 3 as high-poly from ZBrush to make the process faster, that's precise enough for this purpose)
    .- if you make lows by Zremesh-ing, did you subsequently apply a "Project all" from the original high-poly? That's needed to ensure low-poly's vertices are all in the right spots (they never are!!)
    -. did you try setting front and rear distances just a pinch higher when baking? Sometimes the low-poly's surface is too distant from the high-poly's and the result is those blank/shaved spots
    .- did you try baking your normal maps by using level 2 or 3 subdivs as the low-poly mesh? by trying to achieve remarkably low polycounts, sometimes low-poly meshes divert too much from the high-polys, causing those blank spots; using a subdivided low-poly can fix it

    Nothing else comes to my mind, for now....

  • BucketOfNuggets
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    BucketOfNuggets polycounter lvl 6
    I got it to work, something weird happens with the scale if I export as an obj instead of an fbx from maya to zbrush. If I keep everything as an fbx it seems to work for now. 
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