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Having a problem extruding segments on Maya

TheKlu
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TheKlu polycounter lvl 9
Ok, so first of all, hello everyone! :)
This is my problem. When i extrude the segments they don't have the smooth shading as the rest of the model, this is what i mean:

oMHbS76.png

A wireframe view:

epUNMcb.png

How i can fix that? :l
Thanks you! :)
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  • Bartalon
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    Bartalon polycounter lvl 12
    What you are seeing is the vertex normals are split along those edges. Vertex normals control the direction that light bounces off your polygons. If your vertices are split on an edge, light is reflecting off the adjacent polygons in opposite directions which results in a sharp break.

    If you want a visual representation of what is happening, you can view the directions of your vertex normals with Display > Polygons > Vertex Normals (use again to disable).

    To smooth your edges out, select the offending edges and choose Mesh Display > Soften Edge. Smoothing edges averages the vertex normals which allows light to smoothly blend across the adjacent polygons.

    You can also harden edges which can help with dark shading artifacts around sharp corners.
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  • TheKlu
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    TheKlu polycounter lvl 9
    Bartalon wrote: »
    What you are seeing is the vertex normals are split along those edges. Vertex normals control the direction that light bounces off your polygons. If your vertices are split on an edge, light is reflecting off the adjacent polygons in opposite directions which results in a sharp break.

    If you want a visual representation of what is happening, you can view the directions of your vertex normals with Display > Polygons > Vertex Normals (use again to disable).

    To smooth your edges out, select the offending edges and choose Mesh Display > Soften Edge. Smoothing edges averages the vertex normals which allows light to smoothly blend across the adjacent polygons.

    You can also harden edges which can help with dark shading artifacts around sharp corners.

    What you say seems to be the answer, but i think i'm stupid lol
    Ok, well, i've soften the vertical edges from the botton part, so this is what happens :l

    FzBsRVi.png

    It looks almost right but the horizontal edges from doesn't look alright, so i try to make the same to the horizontal...
    Oh yeah, before i do that to the horizontal edges, is weird because the loop is not longer there
    Zbx9p9v.png

    Ok so this is the result now:
    77Ibz5U.png

    Nothing... So i tried to make the vertical loops from the top part and this happend:
    K16cDRJ.png

    I even tried to smooth the whole mesh edges and it doesn't look alright...
    So, if you could help me, i would really appreciate that! :)
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  • throttlekitty
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    throttlekitty
    It looks like you have some hidden and bad geometry at that seam. Is there a horizontal row of faces along that edge on the inside?
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  • TheKlu
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    TheKlu polycounter lvl 9
    throttlekitty wrote: »
    It looks like you have some hidden and bad geometry at that seam. Is there a horizontal row of faces along that edge on the inside?

    Not sure what are you triying to say, i'm quite noob at this...
    This is how it looks from inside:
    83MPkqG.png

    lLq2GjH.png

    Can't find other geometry inside
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  • Bartalon
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    Bartalon polycounter lvl 12
    I think you have what is known as non-manifold geometry. It's a fancy term for "impossible" geometry.

    Edges should never be connected to more than 2 adjacent polygons. It's physically impossible if you think of how that shape would exist as one piece in the real world.

    CZg7l32.png

    Above image: Left mesh has non-manifold geo. You can see the edge where all three polygons meet is breaking the "no more than 2" rule. The center vertical polygon was extruded upward from from the center edge of the two other polygons. If you need to extrude upwards in this manner, you need to extrude a polygon rather than an edge.

    Right mesh has vertical polygon extruded from an edge that will maintain correct geometry.

    Basic rule of thumb: Do not extrude edges from the interior edges of a mesh, only border edges.


    2EfDtpu.png

    This is a makeshift cross-section of the shape you are having problems with. The yellow-highlighted polygons and edges are causing non-manifold geometry because edges were extruded from interior edges one way or another. These highlighted edges should be deleted if you want to maintain the lip you created. If you want to keep the whole under-side of your model, then delete the lip and move the whole under-side portion down.

    UA4Znya.png

    I strongly recommend working with border edges enabled. You can turn on this setting in the Window > Settings/Preferences > Preferences menu. What this option does is it draws edge lines a little thicker at areas where there are no connecting polygons (edges that are only part of 1 polygon). You can see an example of this option working in my first couple images where the outside edges are slightly thicker, visually, than the inside edges.

    It won't identify non-manifold geometry but it will help you identify which edges are okay to extrude, as well as find any unwelded edges resulting from bad extrudes or deleted faces.

    Turning on border edges only applies to all future mesh objects created in Maya, so you will need to do one other thing to get your existing models to display border edges. See next image.

    sjLktS2.png

    Select all your mesh objects and choose this menu option. Border edges should now be on for all current and future models in Maya.


    YqpVHaA.png

    Finally, the Cleanup tool is your best friend. Select your model in Object Mode and choose Mesh > Cleanup... Copy the settings shown above and click Cleanup.

    If your mesh has no problems, it will de-select.
    If your mesh has ngons, those polygons will highlight. Even if it looks like a triangle or quad (4 sides), if it highlights there is something going on and you should investigate. Usually a floating vertex along an edge or something is the culprit.
    If your mesh has non-manifold geometry, the offending vertices will highlight.

    Make your repairs and run the Cleanup tool again. Repeat until there are no more issues.
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  • TheKlu
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    TheKlu polycounter lvl 9
    Bartalon wrote: »
    I think you have what is known as non-manifold geometry. It's a fancy term for "impossible" geometry.

    Edges should never be connected to more than 2 adjacent polygons. It's physically impossible if you think of how that shape would exist as one piece in the real world.

    CZg7l32.png

    Above image: Left mesh has non-manifold geo. You can see the edge where all three polygons meet is breaking the "no more than 2" rule. The center vertical polygon was extruded upward from from the center edge of the two other polygons. If you need to extrude upwards in this manner, you need to extrude a polygon rather than an edge.

    Right mesh has vertical polygon extruded from an edge that will maintain correct geometry.

    Basic rule of thumb: Do not extrude edges from the interior edges of a mesh, only border edges.


    2EfDtpu.png

    This is a makeshift cross-section of the shape you are having problems with. The yellow-highlighted polygons and edges are causing non-manifold geometry because edges were extruded from interior edges one way or another. These highlighted edges should be deleted if you want to maintain the lip you created. If you want to keep the whole under-side of your model, then delete the lip and move the whole under-side portion down.

    UA4Znya.png

    I strongly recommend working with border edges enabled. You can turn on this setting in the Window > Settings/Preferences > Preferences menu. What this option does is it draws edge lines a little thicker at areas where there are no connecting polygons (edges that are only part of 1 polygon). You can see an example of this option working in my first couple images where the outside edges are slightly thicker, visually, than the inside edges.

    It won't identify non-manifold geometry but it will help you identify which edges are okay to extrude, as well as find any unwelded edges resulting from bad extrudes or deleted faces.

    Turning on border edges only applies to all future mesh objects created in Maya, so you will need to do one other thing to get your existing models to display border edges. See next image.

    sjLktS2.png

    Select all your mesh objects and choose this menu option. Border edges should now be on for all current and future models in Maya.


    YqpVHaA.png

    Finally, the Cleanup tool is your best friend. Select your model in Object Mode and choose Mesh > Cleanup... Copy the settings shown above and click Cleanup.

    If your mesh has no problems, it will de-select.
    If your mesh has ngons, those polygons will highlight. Even if it looks like a triangle or quad (4 sides), if it highlights there is something going on and you should investigate. Usually a floating vertex along an edge or something is the culprit.
    If your mesh has non-manifold geometry, the offending vertices will highlight.

    Make your repairs and run the Cleanup tool again. Repeat until there are no more issues.


    Thanks you very much, you don't how much you have teached me today...
    I really appreciate your help! :)
    Again thanks you!
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