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Normal Seams

polycounter lvl 18
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SyaPed polycounter lvl 18
Is there any way to get rid of these normal map seams? I've tried using Melody and Santiago's xNormal with different settings in each but no luck.

Dino.jpg

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  • MoP
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    MoP polycounter lvl 18
    Have you tried using different DX shaders or Max's default Normal Bump material? Sometimes certain shaders don't deal well with UV seams.
  • aesir
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    aesir polycounter lvl 18
    It looks to me like a lot of that seam is in the diffuse map. I think if you work that out first, the normal seams will be less noticeable. It also seems like youre doing an in-viewport shader. I think those tend to show the seams more easily.
  • Ben Cloward
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    Ben Cloward polycounter lvl 18
    My favorite write-up on the topic of normal mapping is by Alan Noon - the lead tech artist at Day 1 Studios. You can find it in this CgTalk thread:

    http://forums.cgsociety.org/showthread.php?t=359082

    There are a lot of tips there for avoiding seems.

    -Ben
  • J.I. Styles
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    J.I. Styles polycounter lvl 18
    looks sexy

    as for the seams, I think I'm one of the lucky ones that's never had any problems (except with max7... ick). I just rip with max8, updated service pack, and always make sure you never break your low poly up if you're ripping areas seperately -- just break up the high poly, not the low... never have seam problems with that.
  • SyaPed
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    SyaPed polycounter lvl 18
    MoP - I've tried a couple other shaders/materials and the seams still show up. Sometimes to a lesser extent but still pretty bad.

    aesir - There are seams in the diffuse map but the normal map is doing most of the damage.

    Ben Cloward - Thanks for the link Ben, lots of good info there.

    J.I Styles - Hmm... I've been breaking up the lowpoly when rendering normals. I'll try giving it a go keeping it solid.

    Oh btw, you can probably tell but that's your shader I'm using. I'm really liking it.

    And hey to a fellow aussie wink.gif
  • MoP
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    MoP polycounter lvl 18
    Ah yes, breaking up the lowpoly when it's meant to be a single seamless mesh will cause those seams.
    Normal maps are rendered based off the low-poly normals - as soon as you break polys you will change the normal angle at the break, so when you stitch them back together the normal maps will be trying to calculate lighting based on different low-poly normals, hence the obvious seam.

    For single organic meshes, you need to keep the lowpoly mesh complete (as JI Styles said) - if there are areas you don't want to render, just add an Unwrap UV modifier and move the unwanted UVs out of the 0-1 range, that way you keep the lowpoly smoothing while being able to selectively render areas.

    I only ever render different segments of lowpoly if they're physically separate objects.
  • SyaPed
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    SyaPed polycounter lvl 18
    Keeping the mesh complete has helped alot. There's still some faint seams but I guess that unavoidable. I'm also using the Kaldera normal material in this pic which helps too.

    Unfortunately there is still some weird stuff happening on the inside of his legs and a few other places. I think this might be xNormal's fault though, as tests I've done with Kaldera's normal mapper doesn't create these. Problem is I can't use Kaldera for the final normal map as the highpoly mesh is too big for max to handle. frown.gif

    Dino2.jpg
  • Neox
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    Neox godlike master sticky
    Try to import the file while in bounding box mode, then set the properties to show as bounding box and you can handle your file in max, i handled 10 million polygons with that once, you can't see it but you can work with it, that's the way i'm creating my normalmaps with cryteks polybump tool.
    You can't avoid some seams, only if all faces are perfectly relaxed rotated and scaled to each other on your map but this will end in a total mess and lots of wasted UV space.
  • dejawolf
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    dejawolf polycounter lvl 18
    how on earth do you manage to align something to bounding box, and making sure the normal mapping cage is properly set up?
  • CrazyButcher
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    CrazyButcher polycounter lvl 20
    I'd guess he first imports a lower-res version of the hi-res to do the setup, and then import the full hi-res ?
  • Neox
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    Neox godlike master sticky
    as i said, i'm using cryteks polybump tool, I'm not using the cage so i don't care about that wink.gif
    the thing crazy butcher says is one sollution, another is just to use the lowpoly with 40% opacity as a guide in mudbox so i stay in it's volume (I do the lowpoly first and paint directly over it. Who needs a clean basemesh when having millions of polygons?)
    so you can be sure, that importing the highres it fits into the lowpoly so you can just hit the render normalmap button and everything is fine.
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