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Substance to Unreal, lighting issue

Can anyone help? I haven't used Unreal in a long time, and I'm struggling.

I'm trying to get my meshes from Substance to Unreal, but after setting up the material, it has extremely strange lighting, and looks completely different to how it did in Substance. You can see that Substance's lighting was clean and uniform. But Unreal's is all over the place. When I view the mesh in unlit, it's fine, but no matter how else I arrange the lighting, it looks like the image on the right.

BTW the image from Unreal is in the Blueprint editor.

Anyone know how I fix this? Is it my lightmaps? Is it my UVs? My texture imports? I've tried looking online for advice but I can't find the same issue anywhere else.


  • icegodofhungary
  • sprunghunt
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    sprunghunt interpolator
    There's no shadows in the substance image. It actually looks unlit to me. 

    If you want the same effect in Unreal put a skylight actor in your level and turn up the intensity of it until you don't have shadows. 
  • Bonsparks
    pior said:
    This is not a lighting issue, this is a shading issue. As shown by the undesired shading on this face, that should really be flat :

    This can be caused by :

    • inconsistent vertex normals/mesh shading,
    • no attention paid to the mesh importer settings in UE4 (the default option causes the normals to be recalculated by the engine, which is *not* what one wants 99,9% of the time)
    • inconsistent normalmap green channel orientation (very easy to fix but frequently overlooked by beginners)
    • inconsistent triangulation (or lack of triangulation, causing mismatches when displayed in different environments)
    • inconsistent baking scheme (maya default / max default / mikkt / tb3 default are all different)
    • bad texture settings (normalmap not set as such)
    • Undesired lightmaps (unlikely)

    The TLDR is that none of that is likely caused by lighting itself. The issue is that because of normalmaps, one is "one step removed" from noticing shading problems. Therefore you have to verify every layer of the stack as opposed to just looking at the end result (which looks like a lighting issue, but very likely isn't)

    Good luck !
    Thank you for your reply. The shading on the pillar was indeed caused by inconsistent green channels.

    For the shading on the base, I thought I was correct in separating the smoothing groups by UV channels, but the shading didn't seem to like that there was a seam there, so I merged my UV channels and ran a weighted normals script for 3DS Max, which seemed to work.

    (Excuse the atrocious lighting itself. The scene isn't properly lit, and it's late at night)

    Thank you for your help. I was really wracking my brain over this!
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