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Tris causing normal map issues

Ahsan55
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Ahsan55 triangle
This is a watch for the character I'm currently working on
Smooth shaded

Weighted normals
Wireframe of tris. Had to add this bevel because my lowpoly couldn't catch the bevels in that area even after I manually adjusted the cage in blender
 UVs

Normal map(smooth shaded)

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  • poopipe
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    poopipe grand marshal polycounter
    What's the problem?
  • Ahsan55
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    Ahsan55 triangle
    See first two images
  • pxgeek
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    pxgeek keyframe
    How does the high poly look? Does it also have that shading artefact?
  • Ahsan55
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    Ahsan55 triangle
    No issues I can see  
  • pior
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    pior grand marshal polycounter
    - The first thing to check is the direction of the ray being cast (literally : along the normal of the face). Perhaps this tiny triangle is ever so slightly bent.

    - Now besides that, the way you've built the lowpoly for this watch asset doesn't make much sense. You have these minuscule dense bevels on the areas where the strap attaches, yet you are using very low density in other places that would benefit from some extra geometry.

    If you have that much of a polygon budget to work with (allowing for such tiny bevels), then you should use this budget in ways that are worth it - hence relying much less on the normalmap in order to correct the shading.
  • Neox
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    Neox godlike master sticky
    just look at the lowpoly mesh without wireframe. 

    the shading is just very strong. without more resolution and probably 16bit depth, the normalmap can only do so much. ideally you want as little shading as possible in your lowpoly.
    you can achieve this by using extra chamfers (costs more geo) or using hard edges on UV seams, where it makes sense. any angle around and above 90° i would just harden to relief stress from the normalmap.

    as this is a hard surface object with a lot of steep angles, looks like converting UV seams to hard edges can be done without any extra edits or thoughts, so this would be the first thing i would try.

    personally i would also straighten the pieces that are almost straight anyways

    with your smooth shading you should also definitely resolve these ngons into quads/tris

  • Ahsan55
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    Ahsan55 triangle
    yes the normals appear to be slightly bent should I manually rotate them or something
    to your second point the low poly isn't finished yet I'm just trying to sort the baking issues  low poly without bevel


  • Ahsan55
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    Ahsan55 triangle
    thanks @Neox hardening the edges reduced the artifact just enough so that you cant see it unless you get really close and view it from an angle. should I stop here or try to remove it entirely Regular view
     Viewed from a specific angle
    Edit: Fixed it completely by playing around with the shading and hardening more edges. Thanks everyone for your help.
  • Neox
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    Neox godlike master sticky
    Wait until that normalmap is compressed and it might get worse.
    If you close enough you can always find something. The question is, how close will you ever get?
    I guess if you re structure this area to not have this long thing triangle youd balance it out more. Or you need to give the try more space in the UVs so there are enough pixels to handle it.

    But then again, how close will you be? Whats the Usecase? Check it out at its purpose to decide if you want to fix something that is visible when you crawl in super close.
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