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Smoothing Groups

Hey, I'm having difficulties with smoothing groups and keep getting smoothing errors.
Theres no n-gons as far as I can see. Any ideas? :)

smoothingerrors.jpg

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  • Firebert
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    Firebert polycounter lvl 15
    I'm from a Maya bkgd and I use this script in Max.
    http://www.scriptspot.com/3ds-max/scripts/hard-soft-edge
    I haven't had many problems with it yet.

    But if you wanna stick to traditional smoothing groups here, you'll need to illustrate how you have your current groups set up to really tackle this scenario I think.
  • Mark Dygert
    The first thing that jumps out at me is the long thin tri at the front of the shell exit. It might be wise to carry that loop around the front instead. With the way it is now I don't see it smoothing any better no matter what tricks you pull.

    You can control the smoothing with more geometry but it costs ya tris you might not have to spend.

    Flipping the hidden edge at the back of the shell ejection slot, could smooth it out a little better, at least spread it around a tiny bit.

    It could also be coming from the polys not being properly aligned. If you select all the polys on that side and make them planar it might get rid of the smoothing.

    Also putting the inner part of the shell ejection on a separate smoothing group might get rid of the errors.

    How does this render, the viewport isn't always trusty when it comes to this kind of thing. It's possible that if you put a texture on it and stick it an engine no one is going to see it.
  • MRico
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    MRico polycounter lvl 10
    Sorry for the thread hijack...similar issue..

    triwtf.jpg

    Can someone explain why that weird triangle shading happens? I would like to understand why/how this happens so I can avoid it next time.

    The whole thing is set to SG1 except for that extrusion in the front.

    I tried turning the hidden edge but it only rotates the shading issue, doesn't get rid of it.

    I also tried what Vig sugested...to make all the faces planar, that didn't do the trick either.

    The shading is baking onto the normal maps and I don't know how to get rid of it, any help please?
  • Mark Dygert
    If that's your high poly then you can add more loops around the areas that shade poorly, 3 loop minimum to help near 90 degree angles smooth correctly.

    SupportingSmoothing.jpg
    You should run a few more supporting loops in other places and probably turbosmooth the whole thing, to make sure its has a sufficient amount of verts to light the large areas and transition all edges correctly.

    Normals.jpg
    It might help to visualize the edge angles and blending going on if you apply an "edit normals" modifier. The more unified normals you have going around a sharp angle the better it will smooth.
  • MRico
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    MRico polycounter lvl 10
    Hey Vig, thanks for the help!

    The first image I posted is the low poly...here is the high poly....

    Dies_04.jpg

    I'm trying to bake that trigger guard thing...the dark green metal part.

    Is the image you posted turbosmoothed? hard to tell on the third example of the first image...it's not, right?

    If I were to add an edit poly ontop and make loops like you suggested to bake out the normal map...

    ...then put that normal map on the model in my first image, will it get rid of those shading issues?

    EDIT: I'll try an edit normals mod and check it out...man, there's so many modifiers in there I don't know what they do!
  • Calabi
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    Calabi polycounter lvl 12
    I'll try and explain how I understand it.

    Why you get those shading errors is because the idea behind smoothing is to average out the angle of the surface polygons. Its like its trying to flatten out the whole object(not really but sort of). When theres lots of extreme angles the software trys to blend them in perfectly with the polgyon next to them but it doesnt quite work because as vig demonstrated their isnt quite enough polgyons.

    Its trying to make a perceptibly perfectly curved surface with only two polgyons at a right angle from one another, very hard. I cant imagine how you would do it, but there must be some limit to how much each polgyon can be smoothed into the next. Plus it has to be smoothed in every direction equally, there's only so much a single polgyon can handle before it breaks.

    So the only ways to sort it are to separate the object into smoothing groups which creates lots of hard edges(which is like separating the object into parts), or spread the load over more polgyons if you want to keep the smoothing, as a whole.

    Not sure if thats entirely right or if helps.
  • ajr2764
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    ajr2764 polycounter lvl 10
    Ive had some shading issues with a current model of a subway train similar to whats goin on here in this thread. I've been trying to figure out what to do, Ill see if I can post some images later and see what you'll think. It seems due to using tris in certain areas to keep it optimized is causing issues.
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