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Low Poly Normals are getting baked into my Normal Map - HELP

Alander787
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Alander787 triangle
Hi, I wanted to bake my high poly details on a normal map in Substance Painter, but when I do so and then export the textures, the shading on my model looks weird. Almost as if it had baked in the normals of my low poly mesh, which is smoothed, marked sharp on hard edges with uv seams. 

What am I doing wrong?

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  • Fabi_G
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    Fabi_G polycounter lvl 3
    I think your exact problem would be more clear, if you provided more specific information, ideally with screenshots.
    How does the low poly with normal map applied look like in Painter? Does it look correct in there?
    In which application do you view the low poly with normal map?

  • Alander787
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    Alander787 triangle
    As soon as I get home, I will provide more details with screenshots.

    Also I view them in Blender and Vectary.
  • Alander787
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    Alander787 triangle
    So here are screenshots:



    And I have couple questions.

    1st picture's normals are doomed because of me forgetting to make seams and marking sharp edges, so that could be the problem.
    In the 2nd picture there seems to be baked shading informations on the normal map from my low poly model, don't know why that is.
    The 3d picture's normal map detail should be straight, they did appear straight in SP, but in Blender they are distorted like this.
    4th picture has some weird shading artifacts as well as last two pictures, but I would also like to know, if I should mark sharp edges on that bent part and place seams there or not.
    And also why do I have these weird shading artifacts?

    Thank you for helping me with this
  • Obscura
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    Obscura godlike master sticky
    A lot of those errors, specifically the "x" shaped ones are happening because you didn't triangulate the lowpoly before baking. Different softwares tends to triangulate the mesh differently, so its important to triangulate before baking, and then use that export for previewing too. Also, the lowpoly vertex normals ARE taken into account during baking, so seeing them in the normalmap is expected, but they should not show in the final shading. Lets take an example with a lowpoly  cube with one smoothing group. The shading of it will be still kinda bad due to the low polycount and low amount of vertex normals. If you bake from a highpoly counterpart, the normalmap will fix those shading uglinesses, but in order to do that, the lowpoly vertex normals must have to be taken into account. After a second look on your pictures, the rest of the errors are coming from the non triangulated lowpoly mesh. So... Triangulate it before baking, and use the same mesh for previewing. It should fix the most if not all your errors.
  • Alander787
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    Alander787 triangle
    So I guess then that I will sharpen some edges, because they should be, but aren't and I also should triangulate the mesh. That should fix the problems, shouldn't it?
  • Obscura
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    Obscura godlike master sticky
    No need to sharpen the edges. Just triangulate the lowpoly before baking and make sure to use that same export for previewing too. The baking lowpoly and preview lowpoly must have to have the same triangulation, otherwise these kinds of errors will show up.
  • Alander787
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    Alander787 triangle
    shouldn't the previewing lowpoly be the same as the baking low poly? what could be the diference?
  • Obscura
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    Obscura godlike master sticky
    Damn...You should just do what I wrote .... It really takes like 2 minutes to try and I'm writing things here for like 15 minutes now...Like I described in the longer post, different softwares (say marmoset and substance) tends to triangulate the mesh differently, so the triangulation of the mesh can change. Every renderer uses triangles for rendering under the hood. Even if it allows to display them as quads. The gradients in the normalmap are there because of the triangulation of the mesh during baking. Which is normal and expected. But then, if you put that normal map on the same mesh but its triangulated differently, these errors will start to show up. No more questions, go and try.
  • Alander787
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    Alander787 triangle
    I get it now, thank you.
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