Normal map seam issue...

CaptianPuglet

I'm in the middle of working on a character model and the normal map on the head is being really annoying for some reason. The picture below shows the low poly head with normal map applied which is also shown on the right. Everything looks fine until it gets to the UV seam at which point the lighting goes all horribly wrong. I have actually spent hours trying to figure out what's wrong here, searched the internet, redone the uvw mapping multiple times, baked countless normal maps and all sorts of other things and now I've just run out of steam and wonder if anyone knows what's wrong here and how to fix it?

Ben Apuna

It almost looks as though the vertex normals are pointing the wrong way on the left side, but I think that would show some wonky colors in the normal map... It might be worth looking into anyway, maybe check the highpoly too.

Is your mesh all welded up along the seam? No duplicated verts or doubled faces or anything of that sort?

I hope you are baking with a cage rather than simple ray distance as that seems to solve many problems.

Be sure to add some more padding to your bake settings as well as it seems to be rather nonexistent in your normal map.

I hope that helps.

EDIT:

Oh and what app are you baking in and what app are you viewing the lowpoly with applied normal map in? That might make a huge difference.

rollin

I hope you are baking with a cage rather than simple ray distance as that seems to solve many problems.

? . Definitely not in this case and I'm quite sure not in most cases..


As the normal map looks quite flat at the borders it's obvious it's not the problem for this very wrong shading at the backside of the head (using padding is never a bad idea though)
I guess its the model or rather the shader who is causing this

cptSwing

tangents of the low poly exported into your baking and later your viewing app?

almighty_gir

tried flipping the green channel?

disanski

Are you using max 2012 and the new nitro display if you are and you have gamma and LUT correction enabled it might be because of that .. just a guess. it is located under customize/ preference/ gamma and lut

cupsster

check your channels (most engines use X+ Y+ Z+) max is using one flipped channel i think X+ Y- Z+

CaptianPuglet

Hey guys, thanks for the replies. I baked the map in Max 2012 and I'm viewing using the Xoliul realtime viewport shader. I have tried fliping the green channel it just makes the shading look wrong and the seam problem is still there. I have nitro disabled since it conflicts with Xoliul. Gamma and lut correction is disabled, enabling doesn't fix it. That bake only had 2px padding on it, I tried with 32px and the problem still persists. I am using a cage on the proj modifier not the ray cast distance. The mesh is fully welded and there are no double faces or duplicated verts.

I think its something to do with vertex normals along the seam since the seam essentially splits one vertex into two.

How do I check the channels cupsster?

CaptianPuglet

I noticed something weird. My normal map works. However, if I open the file in photoshop then save it out and re-apply it to the mesh (even with no edits) it goes like this.

cptSwing

Maybe you need to renormalize (using xNormal's PS tools, for instance) before saving.. then again, if you haven't edited anything, you shouldn't have to..

Stupid question, but are you inadvertently saving to CMYK or something of the sort?

EarthQuake

CaptianPuglet wrote: »

I noticed something weird. My normal map works. However, if I open the file in photoshop then save it out and re-apply it to the mesh (even with no edits) it goes like this.

Gamma/Color Correction issue most likely. Try using the default color profile in photoshop.

cupsster

EarthQuake wrote: »

Gamma/Color Correction issue most likely. Try using the default color profile in photoshop.

Could be the case as well..

Wesley

I had this problem with Photoshop as well. Normals look fine until I open and re-save in Photoshop. I had horrible shading all along my mirrored seems. Even after renormalizing. Was just my Photoshop having a funky colour profile.