Help with workflow - Zbrush > Maya > Zbrush > Substance??

penisfritzgerald

Hello guys

Well, I will try to explain my problem, which is driving me nuts! I have been trying to solve it by myself, but I can't find a solution and my deadline is approaching.

So, I made this model in Zbrush, and my idea was to texturize in Substance Painter. I did my retopology in Maya, that way I could have my low and hi poly to bake it. After that, I import my file back to Zbrush and did that Divide/Project process. So far so good, I think..


When I export my .obj file directly from Zbrush into Substance and bake, I get some weird results. Like this:


It seems that things are out of place. And when I export from Zbrush to SP as .fbx, I can't even bake...

So I decided to use Blender in this process (lol)... And the whole process was much better than using zbrush to generate the files. The result was this one: 

But as u guys can see, all the small sculpt details are gone if compared to the model from Zbrush. First I thought SP was doing this, but then I realize it was Blender. As soon I import my .obj from Zbrush to Blender, all the tiny details are gone and I was not happy with this result, specially because I've already seen some ppl working in SB with models thar had this ammount of details.. 

I've read somewhere that a good way to import these details to Blender is importing it back to Zbrush..then back to Blender (?) - I've tried that but when I import it to Zbrush all the UV and  the retopology are gone. So it didn't help me. I also read that I could export my maps from zbrush to blender and use them to bring those details back. Is that true??? I could try it...because just look at how my maps are coming out from Zbrush: 



I think now, thats why I had those problems when I export my file directly from Zbrush to SB.
My questions are: 
What's wrong with my workflow? What did I do wrong? Is there something wrong in my UV, or any incompatibility between the uv result from maya and zbrush??? Is there another way to bring those details to blender ir even to SP??

Sorry for the long post, but I really wanted to explain all my steps, it's been quite frustrating.
Thanks in advance for any help yo guysu are able to provide .

Alex_J

It is unclear to me what you were doing exactly, but it sounds like you over-complicated things. You shouldn't try to trial and error your way through this. The overall process of baking seems complicated at first, but it's not really. Spend a few days reading and doing simple test with cubes to confirm workflow before stressing over your final model.

Looks like you got some janky UV's going on. If you upload your low poly model as fbx I'll take a look at it.

penisfritzgerald

Hey Alex, thanks for your reply.
Believe me, I'v read a lot haha. Well, my idea at first was model in zbrush> repotology in maya> then go back to zbrush to export a .fbx file with all my subtools to substance. I think I did something wrong in Maya, but I can't fins what.
This is my UV:

And my file: https://drive.google.com/open?id=10dCh9oFPA5flxPqw98HayqYyEVwXiDbA

Thanks a lot

Alex_J

UV's aren't in 0-1 space. I make a video that is uploading now to show in more detail.

Very cool model btw.

Alex_J

https://www.youtube.com/watch?v=08Pj_PVj2GM&feature=youtu.be

penisfritzgerald

Hey Alex! Thanks a lot for your time! 
I had a lot of ideas, but I was really complicating it.
Finally I was able to bake it with more details  
And thanks for ur compliment, this model was made with the help of 3 cientists, including the guy who found it
Im going to follow u in instagram!

Alex_J

penisfritzgerald said:

this model was made with the help of 3 cientists, including the guy who found it

thats awesome!

cryrid

UV's aren't in 0-1 space.

Yeah, this is practically a requirement for Zbrush. If you do any baking in it and a UV coordinate so much as touches the edge of the 0-1 borders then Zbrush will wrap that coordinate around to the other side of the texture, showing the kind of stretching artifacts you posted. There might be an exception with the MME plugin but utilizing other ranges, but a standard zbrush bake needs them inside 0-1. 

So, I made this model in Zbrush, and my idea was to texturize in Substance Painter. I did my retopology in Maya, that way I could have my low and hi poly to bake it. After that, I import my file back to Zbrush and did that Divide/Project process. 

I'd skip the last part. For maximum convenience, all you need to export from zbrush is the original higpoly sculpt (polypaint is optional, UVs are completely unnecessary). Decimate it if you need to make the file lighter. 

Putting a UV'd model back into zbrush and projecting is only needed if you are baking maps in Zbrush, and that's not something I'd personally recommend. If you have a retopologized model already made and UV'd from another program, just use a different program (Maya, Substance Painter, Marmoset, XNormal...) to bake your maps. You'll get a lot more control over the results, will be able to make use of a lot more tricks, and the results be more accurate for the final model (for example: zbrush isn't going to care about vertex normals, let alone tangent basis). 

penisfritzgerald

Hey cryrid, yes I suspected that. It makes sense. 
I spent these last days studying and testing stuffs, and I've noticed this about zbrush. Maya really give us much more control.

Finally, I've got the the ammount of details I wanted in Substance Painter now, this is the result: 

Now I have all the scales.
I've just got two little issues in my entire model:


I know that it might be related to the retopology edge loops...but I can't find a solution. It was worse before, I fixed the retopology around these areas and add more edge loops but I can't get rid of it. Can u guys give me any sugestion?



Thanks a lot for u both. I couldn't get here without your help!