Normal Map seams in 3ds Max
polycounter lvl 12
Hey,
So I'm having some seam issues in Max. When I display the normal map on my model in Crazybump, everything is flawless, not a seam anywhere. However, once it's in max, there are lighting seams everywhere along my UV seams.
Is it my fault? Or is there something that I'm not doing right in max?
For the record, I baked in xNormal, and I tried flipping the green channel. No difference. Also, I'm viewing this with the xoliul viewport shader. However, I experienced the same seam issues with the offline renderer. So the problem isn't that.
Thanks!
So I'm having some seam issues in Max. When I display the normal map on my model in Crazybump, everything is flawless, not a seam anywhere. However, once it's in max, there are lighting seams everywhere along my UV seams.
Is it my fault? Or is there something that I'm not doing right in max?
For the record, I baked in xNormal, and I tried flipping the green channel. No difference. Also, I'm viewing this with the xoliul viewport shader. However, I experienced the same seam issues with the offline renderer. So the problem isn't that.
Thanks!
Replies
Apps usually use different tangent bases. A map baked in one app should display perfectly in the same app, but probably won't in another app. You just have to test variations. I think Xnormal includes 3ds Max's tangent basis as an option to bake to.
3ds Max is an exception in that it uses a different tangent basis for baking than it does for viewport display, causing seams. It uses the same tangent basis for scanline rendering however.
Just drop it into unreal to trim down the potential offenders.
Before you do that, make sure that when you bake the maps, your space coordinates in Xnormal are set to x+ y-z+; these are the settings that Unreal uses. You wouldn't believe how many times I forget to set them up properly and then I ponder why my normals look like crap.
This is the same thing as flipping the green channel, it just automates it, so I don't think it will solve your problem.
I would recommend previewing stuff in Marmoset, it is the easiest and clearest way to look at props, and it is a game engine, so you can preview what your stuff will look like in an engine. If it looks good in marmoset, it is a pretty good bet it will look good in any other engines too.
I don't preview stuff in xNormal because it can look good in xNormal and bad in other engines. Marmoset is a good impartial 3rd party observer for testing your props. I wouldn't put any stock into whether something looks good in Max.
FYI: Marmoset uses +X +Y +Z, so you don't flip the green channel for it.
It looks like there is a hard edge in the model in Max. I use a hard/soft edges script in Max, and I've noticed that sometimes it doesn't translate properly to smoothing groups when exporting to engines. Maybe something similar is happening to you.
Predator:
I think that Xnormal's display matches Unreal pretty well. Unless my green channel is pointing in the wrong direction, I've yet to encounter any problems where it looks right in one, but wrong in the other.
I got seams or better shader errors with my viewport shader in max (xoliuls)
I thought of doing different smoothing groups for each side to avoid that but i decided to chamfer the edges and do it one smoothing group to have it easier when texutring.
Since i got some "holes" in the mesh there are some sharp tris unavoidable which lead to that effect.
However in Unreal shader this problem is non existent.
Now my question is after reading this thread. is this just normal and you ll better of in testing things in marmoset/unreal etc?