[HELP!] Normal Map showing hairline cracks

artbunny

Hi all,
I've trawled the internets and the "how to normal map" in this forum and outside, and I still can't figure out why my normal map is baking with hairline cracks in it.

I had previously baked a normal map for this asset and it came out perfect. Then I decided to add a few more poly's to the lowpoly version, and re-did the UV. After that the normal map bake came out with tiny little cracks all over!

I've set the whole low poly object to one smoothing group. Rebaked. Turned it off and on again, no luck. Using 3ds 2012.

Does anyone know how to solve this/ what am I doing wrong? Any help would be much appreciated.

Attached is wireframe of the low and high poly asset, plus the flaky normal map. And the old normal that had no hairline cracks (the green channel had already been inverted)

.Wiki

What you´re calling "hairline cracks" is the pixel padding that gets applied after the bake.

http://wiki.polycount.com/wiki/Edge_padding

Without the pixel padding you would see normal map seems on texture mipmaps.

artbunny

Ah Wiki, thank you for the reply. However I just realised the image I attached got compressed and the arrows I drew made it look like I was pointing at the seams of the UV.

My issue is that I'm getting these crazy hairline cracks all over the normal map texture (see middle image attached), where there shouldn't be cracks, and I can't figure out why! (on the right is the old normal that exported smoothly)

Anyone have any idea how to solve this?

edit: I seem to have solved this issue by exporting my normals with xNormal instead of 3ds Max. MAX, why you troll me like that?!

That said, (out of technical curiosity) has anyone ever encountered this problem and know why it happened/ how to solve it?