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Question about baking normal/uv mapping

Hi, I'm having some problems with baking normal map. Could you help me if I done it correctly, should it look like this? Thank you

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  • Fabi_G
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    Fabi_G insane polycounter
    Hi! Can you elaborate/show what problem you're having exactly? Seems you didn't include an image of the lit mesh with normal map applied. 

    Frequently people are wondering about the normal maps different colors that show up along seams, however it's to be expected with a tangent space normal map. What matters is that the lit mesh looks good. Here is a wiki page: Tangent space NM

    Looking at your UVs, you could straighten some UV borders to reduce visible aliasing artifacts along seams (seams cutting pixels at an angle). Personally, I would make use of hard edges at steep angles to reduce shading gradients of the low poly, accompanied by UV splits. To get the most out of the pixels available, you could give hidden parts less space or reuse existing parts of the texture. Same goes for mirroring or duplicating parts (make sure those UVs are offset by 1, outside of the 0-1 space).

    Using the search function, you could probably find more threads related to the topic, as it's a fairly common one.
  • Eric Chadwick
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    Good advices ^^
    Also make sure to add padding outside the edges of the UV islands.
  • ZacD
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    ZacD ngon master
    Looks perfectly normal and reasonable. The stronger the gradients and colors in a tangent space normal map- the more difference there is between the high poly and low poly shading/normals. With a properly synced tangent space workflow, it shouldn't be much of an issue, but it can cause issues when textures get mip'd down to lower resolutions or when using LODs. I'd follow Fabi's advise and mark those places as hard edges.

    Cylinders and tight bevels can sometimes be tricky to get perfect when learning how to use normal maps, definitely check those areas when viewing the low poly with the normal map applied. 

    My main critique of the model is the geometry density could be a little more even, the roof segments could probably use more geometry with how much you're using elsewhere.  
  • Puggy
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    Thank you for your advices. I test rendered it with basic texture and it looks good. I'm creating a set of these stone lanterns and I'll keep in mind even density. I've got one more basic question about edges. In past I ran into problems while baking onto low poly with steep edges and I started to bevel them but I am not sure if I should. Which cube would be better as low poly? Is it better to keep geometry as low as possible or beveled edges give better results/more information?
    Edges in my model
  • ZacD
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    ZacD ngon master
    For a first person game with modern graphics you probably would bevel an asset like that, especially if you expect players to walk up to them. With normal maps you generally don't need to bevel assets if it wont have a noticeable effect on the silhouette, and for a 3rd person or top down game (or something more stylized) you probably wouldn't bevel these assets. 
  • Puggy
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    thanks for clarification!
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