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Mesh shading problem [Solved]

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MomentoDemento polycounter lvl 2


Hey,

I have a general shading problem with my mesh. I made the low poly in 3ds Max.

Everything under 1 smoothing group because there is no hard edge (it's a body of a bow). I tried to fix the shading with weighted normal, unifying normal, add more support edges but nothing works.

I got that feedback at Dinusty discord that there is a problem with my topology but even after I tried to fix that in a hundred ways that also didn't work, so I thought I ask here as well.

Please let me know what can cause this terrible shading.

Substance Painter after baking:

3ds Max before baking:


Replies

  • Ghogiel
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    Ghogiel greentooth

    Triangulate the mesh at export from max before baking. (lots of ways you can do so: just tick the preserver triangulation tickbox on the fbx export dialog or just add a turn to poly modifier and set max face sides to 3 then export to painter)


    (edit it actually looks like you triangulated in the first pic,

    What I would do is first check the mesh isn't too small.

    But what I would be most curious abuot is something to do with normals messing up. So assuming nothing is weird with the geometry, ie no doubled verts etc and the UV isn't fucked up, I'd export the mesh as an obj, then reimport it to a fresh scene with just UVs , then add an edit normals and reset everything and reapply a single smoothing group.

    Crank the AA and resolution and see how that fairs

  • lluc21
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    lluc21 polycounter lvl 5

    The corner is too extreme for the normal map to manage coupled with the very distorted UV's that you must have if you don't have any cuts it's making things hard to manage. If you don't want to add a hard edge there you can try adding a support loop, and even this will only make the issue less visible. Sometimes that is good enough though...

    What is the reason to not add hard edges and UV cuts on the harder angles though?


  • MomentoDemento
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    MomentoDemento polycounter lvl 2

    Thank you for the ideas! It helped a bit, but after all I had to render in 4K with maxed AA, only that helped to hide those shading problems. Unfortunately I still don't really understand what was the main issue there but at least like this it's worked. Later I will try to downscale that normal render back to 2K to stay in my budget and hope that also will be okay.

  • gnoop
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    gnoop polycounter

    All shading issues could be fixed with explicit vertex normals. By projecting them from hi res mesh and face weighting . Sometimes hard edge could be an easy solution indeed. But since hard edges double vertex count in many cases, including this one IMO, it's possible to just have not 90 deg face bend but rather 60deg and have vertex normals parallel. Letting this surface bend be exclusively in the normal map only, not the polygon shading . Would work fine for LODs too.

  • rollin
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    rollin polycounter

    Can't remember atm but this issue is bc there is something shady with your lowpoly going on.

    Something not cleanly done about the normals (partly flipped) uvs (overlapping) or doubled faces.

    Sorry that this is so vage but I had tackled this issue once and my head ist just too foggy atm.

    Baking in 4k with max AA is just hiding this issue.

  • MomentoDemento
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    MomentoDemento polycounter lvl 2

    Yeah, I was able to hide it but yesterday I finally get the solution as well. All what I had to do is to handle the edges as they're hard so set multiple smoothing groups with separated uv islands helped and totally fixed the problem. So basically @lluc21 solved my problem. I had a delusion about the hard edges like they need to be 90 degrees or more but apperantly I have to handle some meshes like that with even smoother edges as well. I'm really happy because this project helped me a lot to improve and thanks for the answers!

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