[Solved] AO artifacts when baking in SD

Justo

I would love to move to Substance for baking, but I've never managed to squash all the little bugs that prevent me from doing so. For example, Substance's Match by Mesh Name feature is excellent for baking AO and getting that occlusion where meshes collide, but I'm always getting artifacts like in the example pictures.

This baking process consists of one FBX composed of various meshes ending with _low, and various OBJs ending with the corresponding _high. I can't use a cage, since SD still hasn't implemented cages into the Match by Mesh feature, and exploding everything would remove the benefit from doing all this work. 

Could anyone who's managed to use this workflow give me some tips? Have you ever had artifacts like these, and if so, what was the problem?

NicolasW

"I can't use a cage, since SD still hasn't implemented cages into the Match by Mesh feature."

What do you mean ? The cage matches the low poly mesh by the UVs, there is no reason why it'd not work.
Concerning the artefact, could you send me the meshes ?

Justo

Hi Nicolas. I said that because in Substance´s Match by Mesh Name documentation there is nothing about cages, and the only thing I could find was a post from Jerc I think back in June saying cages hadn´t been implemented yet. How would one get them to sync with their corresponding meshes? Have a _cage at the end? The baker window does not let me upload multiple cage files, unlike high polys...In that case, should I group all cages into one FBX, and be sure each separate mesh is correctly named?

As for sending you the meshes, I´d be happy to But I will only be able to send them to you in around 6 hours, when I get back home. 

NicolasW

I think what Jerc said, was we do not support multiple cages: if your fbx contains two models with two different materials each using a specific UV set, since the cage relies on UV you can't merge the two cages. In this particular case you'd have to use two cages and for now you can't specify the two cages in SD/SP.

So, if you are not baking multiple texture set, a single cage will perfectly work. As I said the cage does not relies on mesh names but only on the UV information. So even though you have split the low poly objects into multiple parts, the cage can also contain multiple objects, or be merged as a single one, it does not matter.
The only important thing is to make sure the cage has the SAME UVs as the low poly object.

Justo

Thankfully it´s all one texture set this time. I tried grouping all cages and saving them as an FBX (I did not bother naming them since you said their UVs were the only important thing), so the way I baked now in SD was one FBX for lowpolys, one FBX for cages, and multiple OBJs for the highpolys. However, I´m getting almost the exact same artifacts as last time, so I´m assuming I´m doing something stupidly wrong. I PMed you the meshes too, in case you have some minutes to check if there´s any obvious flaw in my setup...in any case, thanks for the help Nic.   

NicolasW

Ah sorry, for some reason I've not been noticed I got a pm..
I'll take a look and get you posted!

NicolasW

So I imported the meshes in max to check everything was OK and it looks like some parts have weird normals:



But I'm not sure it corresponds to the artefact you show on your screenshot (the image is quite small..).
This is what I get in Designer (match by name on, single fbx for low, single fbx for cage and single fbx for high).


Edit: I rest the normals in max and rebaked. I'll send you the meshes by pm.

Justo

Thank you for taking the time to try some test bakes Nicolas. The problem you show is definitely not what I expected, nor can I reproduce it altering parameters inside the baker. Are you sure you exported the normals correctly when you grouped the highpolys as an fbx? Stranger still, much like you said the artifacts that I was having seemed to have disappeared...

Justo

A little late in doing this, but if anyone ever reads this...

The problem was in the naming convention I was using and more importantly in the highpoly's normals. NicolasW kindly helped me out via PMs and told me all this. Now that all that's sorted out, I can definitely say I looove baking everything now in Substance. Fast and super comfortable!