Baking normal map from high poly to low poly

Support Materials and Textures
#1

Hi guys, thank you for coming. :smiley: I have encountered 2 problems when baking the normal map from high poly to low poly. I would be appreciated if there is any help.

I have 2 mesh, 1 is the low poly, and the other one is the clone of that mesh with a subdivide modifier up to level 3 (I call it high poly).

From P1 in the picture, there is a octagonal cylinder with a circle cylinder “shadow” baked from high poly on my octagonal cylinder. But what I want to is a circle cylinder (or near circle) without corners after the normal map has applied. I have followed Blender Guru’s Anvil tutorial but I don’t feel like I have missed something.

For P2, my normal map appears some red and green area. From what I’ve learnt from blender guru, it is not a good normal map. I tried changing the ray distance setting, but no matter how I set there are red and green.

NormalMapProblemE
NormalMapProblemE1920×1024 400 KB

My blender file

Thank you so much if you can shed some light for me or other new users who might face the same problems.

#2

P1) A normal map does not modify your geometry. An 8-sided cylinder is an 8-sided cylinder. You can’t make it “without corners”, if I understand correctly what you’re asking. If you want it to look circular, use more sides.

P2) Ray distance won’t help you here. Those are areas where:

  • your high-poly and low-poly deviate from each other, substantially, and, because of that (very important):
  • the normals on your low-poly are pointing in such a way as to miss intersection with the high-poly completely:
    image

On that particular rim of the cover, all the rays that are shot from the low-poly will always miss the high-poly, no matter how you adjust the ray distance.

You’ll either need to edit the objects so that they follow each other more closely (very important especially for these concave surfaces), use a cage for baking, or rethink your approach and make the sides and cover their own meshes, just as they are distinct objects in reality.

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