How do you composite the additional maps in Substance Painter 2?

WindchILL

So my situation is that ive baked out maps for several sets of objects since my character is a fairly complex knight with several armor pieces that intersect other parts. My problem now is figuring out how to composite them all into one map. AO and normal seems easy enough (overlay blend mode in Photoshop), but how do I do the other ones like world normals/position/thickness/etc which have strange colors in them????

musashidan

Are you aware of SP's 'bake by mesh name' feature? It's the same as doing an explode bake, without the exploding. If all your parts are on the same texture sheet you can name all your low/high parts exactly the same, with the suffix _low and _high, respectively, and export all parts as a single .fbx. Then in the baking settings make sure match by mesh name is active.

WindchILL

@musashidan would this work if I'm using a UDIM-based texture set? I was just made aware of this by someone else so I gotta try this tmrw

musashidan

Only if you're rendering offline. Not in-engine (ue/unity/etc) Because SP works in 0-1 uv space each udim tile is a separate texture set.

WindchILL

@musashidan so just to clarify, exporting both the highpoly and lowpoly as an fbx preserves each object name right? and also im assuming the two fbx files also have to match names with _high and _low respectively

musashidan

No, the .fbx file name doesn't matter. It's the names of the meshes saved within the file. So for instance if you had a gun made 3 parts: body/handle/trigger, it would be like this:

These 3 meshes would be exported in an .fbx file, together as a selection, and might be named gun_game_res.fbx

body_low
handle_low
trigger_low

These 3 meshes would be exported in an .fbx file, together as a selection, and might be named gun_highpoly.fbx

body_high
handle_high
trigger_high

Then in SP baking settings>Match dropdown>select 'by mesh name'

The baker will look for these names and the .fbx file will respect them. So when you bake, each mesh will be baked only from the matching name and will ignore any high-poly targets with a different name.

It's important that names are exactly the same. The suffix can be customised in the baking options to your own '_xxxxx' naming convention, if you prefer.

WindchILL

@musashidan strange, I selected all of my lowpoly and it exported fine as .fbx but when I tried taking it to substance painter it gave me an error "[Scene 3D] Failed to load 3D scene. FBX : Could not import scene properly."

Jerc

Could you try exporting again in a different location? This error happen seemingly at random and I haven't been able to figure out what is causing it.

musashidan

What version of fbx are you using? 14/15 is solid for me.

WindchILL

@musashidan @Jerc
I've used zbrush4r7 to export the highpoly fbx and maya 2016 for the lowpoly one. I've tried exporting to all sorts of folders on my computer but it still doesnt work.

Currently I've just imported the lowpoly as an obj and it reads fine BUT whenever i try bake by name from the highpoly fbx the software just crashes (sometimes the app just shutting down without any sort of error message). I have no idea why this happens and its stressing me out...I've tried further testing and found out that SP auto-closes whenever I try to bake normals/AO/ID/thickness at any resolution. the other additional maps seem to bake out fine...

musashidan

I'm guessing it's zbrush naming convention. It uses a hyphen instead of an underscore. You need to press alt+shift to use an underscore. Without an underscore SP will not bake by name. Also, as far as I know .obj doesn't respect the mesh names within the file. You can open an .obj with notepad and see what it has written to the file.
Personally I will always export low and high from the same package for baking. In my case, 3D Max. That way I know everything is 100% on export for bake.

WindchILL

I've made sure to avoid that, thats not the issue. I've realized that i didnt have "grp" turned off on EACH subtool, and made sure. THIS time substance doesnt crash anymore it just says "baking failed. bad allocation" whenever i try now. Im about to pull my hair out, why can't i just bake my maps...

i only know zbrush and maya for this workflow, but even though i dont know max theres still gotta be a way for this to work

VEDAMER

If you're getting the same problem, what I did is I checked UV maps of the intersecting meshes and it was possible for my project that I can separate those UV sets. IF you select both intersecting meshes, you will find the UV sets are overlapping. If so separate them (if possible)
you will not see the problem anymore.