Substance Painter - AO baking errors from reimported normal map

Pegbird

Hello all,

I've been getting to grips with Substance Painter at work and have encountered a strange issue.

I want my AO and curvature map to include the extra normal map details that I have painted into my mesh, so I am trying to do the workflow that everybody uses for this:

-Bake Normals from High Poly
-Add new details in Substance Painter
-Export New Normal map with combined details
-Reimport it as the Base Normal map
-Bake AO and Curvature (to include new normal details)

The curvature seems to work fine, but I am having some strange artefacts in the AO map. There are several gaps or "blank spots" over the mesh where no AO information has baked for some reason, and the edges have a strong seam. It looks like this:






Does anybody have any idea what could be causing this? None of the Common/AO baking settings seem to have any impact on this. Really liking Substance besides this strange bug.

Thanks!

Fuiosg

I get the same results, think it might be broken.

Pegbird

Thanks for the reply Fuiosg, its good to know somebody else is experiencing this. Can anyone else confirm / advise?

Froyok

To make things easier to track we will provide support on the duplicate thread on our forums : https://forum.allegorithmic.com/index.php/topic,17170.0.html

Pegbird

Froyok, I deliberately posted this here on Polycount to reach a wider group of people. So far my thread has sat on the Substance forum for several weeks with no solution or support.

Had a new Graphics card installed at work (Nvidia 1070, Drivers 381.89)
Also we updated Substance to version 2.6.1

I re-baked the same model using all the same settings and the results have improved, but there is still a problem with the AO calculation. It looks actually quite different than it did before, but I dont know if this is the substance update or the new Graphics Card / Drivers.

The Curvature map by comparison is much better, so what is up with the Normals > AO calculations?
Would greatly appreciate anyone with any info about this.

Thanks

Jerc

Are you using a high poly mesh to generate the AO? The artefacts look like what you would get by generating the AO from the low poly+normal map and the normal map green channel was inverted. But the fact that your curvature bakes fine is intriguing.

Pegbird

No, I am baking from a low poly+normal map (which itself was baked in Substance). I am doing this because the extra normal map details I did in Painter were not being used in any of the Masking / Grunge generators (because there was no AO or Curvature there).

From what I understand, you guys are trying to figure out a way to 'update' the AO + Curvature maps on the fly, as new normal map details are painted onto the model.

In the mean time however, this is a work around that many people are using and was even explained in one of the Allegorithmic tutorials. I am just curious if this is some sort of bug, or if its an issue with my particular hardware/drivers. As you rightly point out, it makes no sense that I am getting good curvature bakes but bad AO bakes. At least one other person is getting this, as indicated above.

Jerc

I can't manage to reproduce the issue on my side. Would you be able to send me the Painter project file?

Pegbird

Sure thing Jerc, I have sent you a PM

Jerc

This is really weird, I can't figure out why the AO is generating as if the normal was inverted. If you create a new project from scratch, does the same behavior happen?
A workaround you can use in the meantime is to switch your project to OpenGL ( Edit > Project Config ) before baking your AO, and then switch it back to Dx after the bake.

Pegbird

Thank you for taking the time to look at this Jerc. Yes it happens if I create a new project, I have done this several times. The fact that you are getting the same problem as me on an entirely different machine makes me think it is a weird DirectX bug with SP. The Open GL workaround you suggested works very well, here is the result:





Ideally, there should be some sort of "Update AO/Cavity/Height from Normals" feature in SP which takes all the extra normal map detail you have added and gives it AO/Cavity info so that when you use all of the procedural generators it actually includes them.

In the mean time I will use the OpenGL workaround to the workaround