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Shading issue on flat surfaces?

guitarguy00
guitarguy00
polycounter lvl 7
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guitarguy00 polycounter lvl 7
Hey guys, I'm following the Blade tutorial made by Tim Bergholz and I'm getting a strange shading issue on an area that is presumably flat? This occurs when I assign a smoothing group to that area:



What do you guys think? Here is the wireframe shot:

Any help would be much appreciated!
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  • ZacD
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    ZacD ngon master
    Flat areas like that will still try to smooth with the edges that start to curve around the sides. You would need to either weight the edges or add an edge loop along the end of the flat areas. 
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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    ZacD said:
    Flat areas like that will still try to smooth with the edges that start to curve around the sides. You would need to either weight the edges or add an edge loop along the end of the flat areas. 
    Ahhh  I see. Will it be an issue if I leave it as is? I'm going to bake a high poly version down to this one(low poly). When you say weight the edges, do you mean give them a seperate smoothing group? Thanks for the advice by the way.
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  • Neox
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    Neox godlike master sticky
    is this supposed to be your high or lowpoly? if the high, well it needs support loops. if its the low then a normalmap will fix these issues
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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    It's the low poly. Just very strange considering it is not an abrupt change in angle? I'm new to MAX(was using Maya before) so I want to be sure before I move on to save me having to come back hehe.
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  • Dividuum
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    Dividuum polycounter lvl 6
    Maybe try out the Face Weighted Normals plugin. Should fix you problem, but use it at the end of you workflow because if you work on you r mesh after applying it the normals won't update. But this is easy to fix if you put another edit poly above. Hope this will help you ;)

    http://wiki.polycount.com/wiki/Face_weighted_normals
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  • poopipe
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    poopipe grand marshal polycounter
    Or just harden the edges at the 90 degree corner
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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    poopipe said:
    Or just harden the edges at the 90 degree corner

    It's hard to show in a picture but the angle looks much shallower than 90 degrees.

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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    Dividuum said:
    Maybe try out the Face Weighted Normals plugin. Should fix you problem, but use it at the end of you workflow because if you work on you r mesh after applying it the normals won't update. But this is easy to fix if you put another edit poly above. Hope this will help you ;)

    http://wiki.polycount.com/wiki/Face_weighted_normals
    Thanks I will check it out :D Are there any drawbacks to using this?
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  • Dividuum
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    Dividuum polycounter lvl 6
    Not really.. It's just another way of calculating your normals, just the things I have mentioned, It's not as flexible in the workflow
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  • ZacD
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    ZacD ngon master
    Face weighting can be an extra step. Sometimes it's quicker to face weight, sometimes it's quicker not to worry about it. Definitely a tool artists should be aware of, can be a quick fix for highpoly issues, and an optimization and artifact reducing tool for lowpoly. 

    So learn both how to use edge loops to control shading and face weighting :D 



    The smoothing is happening between these 3 vertexes. Since the middle vertex is between a 2 surfaces at 2 difference angles, it's going to smooth between them, causing your unwanted shading. 



     


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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    ZacD said:
    Face weighting can be an extra step. Sometimes it's quicker to face weight, sometimes it's quicker not to worry about it. Definitely a tool artists should be aware of, can be a quick fix for highpoly issues, and an optimization and artifact reducing tool for lowpoly. 

    So learn both how to use edge loops to control shading and face weighting :D 



    The smoothing is happening between these 3 vertexes. Since the middle vertex is between a 2 surfaces at 2 difference angles, it's going to smooth between them, causing your unwanted shading. 



     



    ZacD said:
    Face weighting can be an extra step. Sometimes it's quicker to face weight, sometimes it's quicker not to worry about it. Definitely a tool artists should be aware of, can be a quick fix for highpoly issues, and an optimization and artifact reducing tool for lowpoly. 

    So learn both how to use edge loops to control shading and face weighting :D 



    The smoothing is happening between these 3 vertexes. Since the middle vertex is between a 2 surfaces at 2 difference angles, it's going to smooth between them, causing your unwanted shading. 

    Thanks for that, I understand now. Is it a major issue or will the normal map take care of it? I think the circular bevels are also contributing to the shading irregularies. Would they also need edge loops around them?

    I'm trying the weighted normals plug in now. I'm fairly new to MAX as I was previously using Maya which didn't have this issue because it comes standard with weighted normals hehe.
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  • ZacD
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    ZacD ngon master
    The high poly needs to be mostly shading error free, tiny smoothing issues are ignorable if they will be smaller than a few pixels. 

    The normal map on the low poly will fix shading errors only if you are using a synced normal map workflow, otherwise, the lowpoly needs to be free from most shading errors. Even if you are using a sync'd workflow, compression and not enough texture resolution may still show artifacts. 

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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    Tried the plug in, cleaned it up bigtime! Turns out this feature is standard in Maya which I was using prior to this so I found it weird how I neved came across this problem in Maya before.

    Still gotta mess around with the settings. Should be some tutorial on Youtube about it. I think the linear shading issues now are probably related to the geometry which I will try alter.
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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    Still can't get rid of all the shading. Max says I have T-verts in those area which can cause shading errors. I assumed that they were N-gons but in most cases they are quads. Am really stuck here.
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  • Axi5
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    Axi5 interpolator
    guitarguy00 said:
    Tried the plug in, cleaned it up bigtime! Turns out this feature is standard in Maya which I was using prior to this so I found it weird how I neved came across this problem in Maya before.

    Technically that Maya feature isn't the same, Maya does a weighted average of the normal whereas that script does a comparison and chooses the larger of the two values. The two will produce similar looking results but they will differ on some curvature.
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  • Axi5
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    Axi5 interpolator
    guitarguy00 said:
    Still can't get rid of all the shading. Max says I have T-verts in those area which can cause shading errors. I assumed that they were N-gons but in most cases they are quads. Am really stuck here.
    Show your wireframes!

    Also, experiment with this feature:
    https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/3DSMax/files/GUID-26CAF521-851A-4F91-8937-C44B40BB20F2-htm.html

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  • guitarguy00
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    guitarguy00 polycounter lvl 7
    Axi5 said:
    guitarguy00 said:
    Still can't get rid of all the shading. Max says I have T-verts in those area which can cause shading errors. I assumed that they were N-gons but in most cases they are quads. Am really stuck here.
    Show your wireframes!

    Also, experiment with this feature:
    https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/3DSMax/files/GUID-26CAF521-851A-4F91-8937-C44B40BB20F2-htm.html



    I checked all of those features in Xview, I got some overlapped UVW faces but I don't think those are an issue as I have not yet UV unwrapped hehe. A few T-verts, no isolated verts, no overlapping edges etc.
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  • Axi5
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    Axi5 interpolator
    You still need better topology in that area, try having an inset edge loop around the whole flat part side of it, that'll act as a support loop for the shading. It'll require some tweaking of your topology to achieve though.

    For the sake of it, try putting the flat side's faces into a unique smoothing group by themselves (make sure they're only in that group) and see if the shading issues improve (I expect they will), them slowly add more and more connected faces to the group and you'll start to realize how the topology is affected it.
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  • Neox
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    Neox godlike master sticky
    what does it look like in your final output engine? seriously it doesnt really matter what it looks like in max. Maya by dafault shades by face and area angle, max doesn't so the shading on lowpolies will always look inferiour. But who cares? How does it look with normalmaps applied in the engine is all that matters.
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  • CarlCraft
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    CarlCraft polycounter lvl 9
    Like some have said before, add another edge loop on the flat surface... Just try it first and see the results, then go back and clean up the topology

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