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So, I'm still quite new to high->low poly workflows and I'm having an issue where I'm not getting any geo in my normal bakes from my high poly to my low poly. My expectation is to have the pentacle shown on the low poly via normal map (with diffuse roughness coming after).

I've played around with various scale factors for the low poly, extrusion and ray distance via bake process. I think I understand how max ray distance works (from Blender Guru's how to bake perfect normals video), but I'm still not sure I understand the process of baking normal from high to low as I'm not getting the results I expect.

Do I need to use a cage? Is it true that blender calculates normals from shooting rays inside the low poly? Does this mean I need to extrude my low poly more? Still new and learning.

Example normal bake image: Example normal bake image

Here's the blend file: https://pasteall.org/media/2/0/2096a67028a89ca823677505a6115558.blend

Edit: I noticed a bug in the version of the blend file I uploaded, I corrected it and do indeed have LowPolyMat set to Baked1K image texture (selected) for baking purposes.

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  1. First, you have ray distance 0 this blocks ray cast to reach the geometry below and above the surface.

enter image description here

  1. You have top and bottom part of the box overlaid each other, so that normals from bottom part bakes on top of top part. So you have to redo UV map.

Normal bake after moving bottom part away: enter image description here

  1. Selected to active is not set. Don't know, is it the issue.

And of course set render samples to something around 8 to get the results faster:

enter image description here

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  • $\begingroup$ I do have ray max distance set to zero - it's my understanding that this doesn't mean zero length rays but instead means there is no limit to the length of the ray. Am I in error? Also could you link the corrected blend file? or describe what specifically you did to correct the UV map? I can clearly see you did it right I'm just not sure how or what to change. Yes, I do have selected to active checked - the file I uploaded had issues with it because I mod'd it, was unsuccessful in reuploading. To your last point, agreed, max cycles should be fairly low thank you for pointing that out :) $\endgroup$
    – Kessair
    Commented Apr 25, 2022 at 18:51
  • $\begingroup$ hm, for ray distance seems to be you are correct, but not the extrusion $\endgroup$
    – Crantisz
    Commented Apr 25, 2022 at 19:43
  • $\begingroup$ understood - could you elaborate on how you changed the UV map, and did you do this to the high poly or the low poly or both? Thank you so much! $\endgroup$
    – Kessair
    Commented Apr 25, 2022 at 22:50
  • $\begingroup$ Only low poly map is important, high poly doesn't have to have UV map at all. You have top and bottom part basically in the same position, fix that $\endgroup$
    – Crantisz
    Commented Apr 25, 2022 at 23:01
  • $\begingroup$ Got it, that resolved it - thank you so much @Crantisz $\endgroup$
    – Kessair
    Commented Apr 25, 2022 at 23:50

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