Normal Map Seam Issue

[Nhoefer146]

I've been battling seams like this one on multiple static meshes now, and I decided to come to the community to help me out. I put together a picture showing what I am having problems with.


1. Here is the seam on the mesh that I'm working on.

2. Here is the UVW map that I laid out, but if you notice, I split the spirals in half to optimize texture space.

3. This is the rendered normal map without any editing. One thing I point out is that I don't even have anything in that texture space but the seams are still there!

I am just wondering why this is happening and if I can fix this with the spiral's uvs remaining split.

Thanks!

[darthviper107]

Not with the UV's split like that

[Nhoefer146]

Can you be a little more specific?

[juguefre]

did you set a smoothing group on the split?

[Nhoefer146]

The smoothing group connects through the split, and when I look at the mesh without the normal map, there isn't any seam...
So the normal map is the direct influence of the seam. I just can't figure this one out!

[TheAgent]

Try setting SRGB on the normalmap's texture property.

[Nhoefer146]

What do you mean SRGB?

[TheAgent]

In the texture properties of the NormalMap, in the content browser.

You can set the SRGB property to true, sometimes that fixes seam issues. Or false, if already set to true.

[darthviper107]

When you split the UV's at a point it will separate the mesh at that edge. You can try to fix this by separating it already in 3ds Max and then rendering a normal map to smooth the mesh to correct the seam.

[Nhoefer146]

The Agent: I tried both true and false and nothing helped, but would you be willing to explain what SRGB stands for? I haven't looked into it at all and I would be greatful!

darthviper107: Do you mean separating the geometry at the seam that I created? or use different smoothing groups at the split?

[YakZSmelk]

Is there overlapping UVs on the model?

[darthviper107]

The Agent: I tried both true and false and nothing helped, but would you be willing to explain what SRGB stands for? I haven't looked into it at all and I would be greatful!

darthviper107: Do you mean separating the geometry at the seam that I created? or use different smoothing groups at the split?

Yes, make a copy of your mesh and separate the mesh where you created your UV seams. Then use Render to Texture to bake the normals from your original mesh onto the one with the UV's separated. The issue is that UDK will separate your mesh on the smoothing groups (which isn't a problem for normals) and on your UV seams, so you're simply correcting the normals with a normal map.

[Nhoefer146]

YakZSmelk: there is overlapping UVs, but I believe that shouldn't affect the model if I don't have any "normal" information for the spirals.

darthviper107: Thanks for all the help! Now that I've started using the forums, I've found out so much information helping me! Your idea works if I split the uv's, and I also found another idea to leave the uv's together: just
use a 1024x512 texture! I just hate when the solution's are so simple that I just look over them...