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Blender: Help with shading?

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  • MasterWorks

    So I am having trouble with the shading of object and I don't know why. I identified that the line segments going diagonally affect the light reflection, but I still run into lines showing for quads for the holes.

  • okidoki
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    okidoki triangle

    Your front (and top ) doesn't seem to be co-planer anymore.. (scale to 0 in Y and Z direction) or maybe also check the normals (recalc or enable face orientation overlay) or double geometry (merge by distance).. also try make it "cleaner" (?):

  • Michael Knubben

    Good advice so far. Additionally, try deleting any Custom Split Normals under the 'Geometry Data' section of the Object Properties. While you're there, check what your autosmooth is set to. If it's set to a hard 90, any small deviation as shown by @okidoki will result in a smooth edge

  • MasterWorks

    So, I've checked the normals and they're oriented correctly. The extra lines are to help remove Ngons and some helped Clear some of the issues (I actually started having issues when I started to clear geometry so I kind of don't want to)

    I'll try to straighten out some geo, but it can affect the size of the extrusions if I just scale or the bevel will be altered. I didn't know about custom normals being made so I'll check that out.

    Interestingly The subdivision modifier using simple shade smooth fixes almost all of this. I'll post the results tomorrow or the day after.

  • MasterWorks

    I love you. Deleting the custom split normals solved the shading issues I think entirely (have to do a closer look). I didn't know that was a thing until now. I'm honestly not sure how autosmooth does the calculation. Is it anything above the number or below the number (< than 90 or than 90. )

  • Michael Knubben

    It adds hard edges automatically at any edge with an angle greater than the set angle.

    Set your mesh to Auto Smooth and 180: everything will be smooth, because no angle is is greater than 180. This is great if you want to add hard edges manually and not have any interference from automatic processes.

    At 90, it adds hard edges at any angle over 90 degrees. So all edges on a default cube. If one of them gets nudged a bit though, you might get a weird artifact on just that one edge, which might have been part of what you were seeing.

    The Custom Split Normals are basically all the normals, including manual tweaks, baked into the mesh. This can happen when applying certain modifiers, or often: when bringing in meshes from external software.

  • MasterWorks

    Thank you for responding so quickly. I'm going to try to make a habit of using this forum for now on. Currently I tend to forget to go on here.

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