Mudbox still can't generate tangent space normal maps

Vii

Edit: Generating normals from xnormal result in the same issue. Can't even troubleshoot this, there's nowhere to start from.

1. Open Mudbox 2014/2015/2016. I used fresh install with no saved settings.
2. Grab any 'starting point' object
3. Sculpt over the seam
4. Export & Extract into Maya, any version, any settings so long as it's tangent space normal
5. The normal map has nasty seams in any app/renderer

Does anyone know a fix?

JedTheKrampus

Vii wrote: »

And no, using another program isn't a solution to mudbox not even having the most absolute basic functionality working after almost a decade.

It's the only fix that's around unfortunately. Look, xNormal is a production-quality baker that's not really hard to use. If you have xNormal and Handplane you can easily bake normal maps that work in 99% of renderers out there, choosing between MikkTSpace, Unity, Max, Maya, Source Engine, and UE3. You can write a batch file to automate the bakes for a particular asset too, making the rebake process really easy. Why anyone still uses a broken baker like Mudbox's in this day and age is beyond me.

If you can't figure out how to use xNormal you could always try baking in world space in Mudbox and then use Handplane to convert the world space map to tangent space. If you need to convert to Mikk you can do that with xNormal's object space to tangent space converter.

If you're not satisfied with Mudbox's glacially-paced development, perhaps it would be worth considering a move to a different sculpting program.

Edit: Also seams like that on UV seams are to be expected and will happen with any tangent basis. To diagnose normal maps you need to view them as normal maps, because something that looks odd on a bake might actually look OK on the model.

Vii

You started responding prior to my edit.

XNormal has the same issue. Testing some things and will post again soon..

The issue with the seams are much more severe than you apparently think.

WarrenM

If every baker is giving you seams, it's likely a problem with the UVs. Not enough padding or whatever.

Vii

Did you read the OP at all? It occurs with the mudbox starter models as well as my own.

Anyway, I think it's fixed.. *I think*. When I first encountered the issue I was using Mudbox/Maya 2016 and I dumped the texture into the depth and changed it to tangent space normal, the problem occurred. It had sRGB set for color space etc, and there's no way to turn it off. I found when having Maya make a file specifically for normal map that's off but I still can't find any way to do that myself (doesn't matter, so long as I'm aware that it happens).

I continued to investigate and did things such as playing with the normals at the seams to see if anything would change and I think I accidentally replicated the issue through another means so even when I fixed the color space issue it seemed to still occur and this also caused it to appear to occur in other renderers.

Freak occurrence, I guess. For now things are working and there's no seams (not sure why people always insist there are with tangents whenever someone raises an issue! There definitely are not when they work right).

Cheers for the assistance

Eric Chadwick

Color differences across uv seams are to be expected with tangent space maps.

In fact it's necessary to get proper lighting, as long as your baking tool uses the same tangent basis as your display tool.

Here's a picture and some text that helps explain it.
http://wiki.polycount.com/wiki/Normal_Map_Technical_Details#UV_Coordinates

If you're still seeing a seam when the map is used as a normal map (not as a color map, in your OP) then you may have a problem. However it's fixable, see Jed's post.

Vii

No comment.

Eric Chadwick

Lol. You're missing the point. Or else you're posting the wrong image. Post an image showing a shaded seam.

WarrenM

Did you read the OP at all? It occurs with the mudbox starter models as well as my own.

I did actually. Understand that just because a model comes with Mudbox, that doesn't mean it's been set up correctly. All it means is that it came with Mudbox.

Eric Chadwick

Also, Mudbox normal maps may not work properly in other apps. It depends which tangent basis they're using in their baking tool, vs. the tangent basis used by other tools.

fade1

Sorry. But I think there is no problem at all. It never occured to me and I just tested again with your head example. Shows just fine in Maya.

Maybe your problem comes from using the wrong base model. Mudbox alters the base model when you sculpt on it. You need to export the level you are baking to again, so the baked textures show up right...