ZBrushCentral

goz mental ray issue

ZBrush Usage Questions
#1

Hi all, thanks for reading this.

I’ve just discovered GoZ and it looks amazing. I’ve spent hours and hours trying the old-fashioned way - exporting displacement maps, trying to convert .tifs to .maps, make sure I’ve got everything flipped the right way… (ect…) and goz seems to solve everything with one fell swoop.

And its idiot proof right? Well this idiot won’t lay down that easy…

It’s just my luck (or stupidity) - I can’t seem to get it to work.

So I built my low poly in silo. I brought it into Zbrush and sculpted away. I then created a displacement map and normal map and hit the goz btn.

Maya fires up and my low poly mesh shows up, but when I go to render with mental ray there’s no mesh - the model is gone! It seems to show up in the software renderer, but obviously… ahem… the less said about those results produced, the better.

Could it be a uv problem? Admittedly I didn’t go through the UVLayout process this time -do you actually still need to, or does goz take care of that for you?

Anyway it’s been a long and frustrating few days so I hope this all makes sense. I’m getting ready to start from scratch with my model (from low poly at least) and give it another shot, but if someone could offer a solution I’d be very grateful.

Cheers guys and great community, I’ve learnt so much from this board.

link
ps i’m using zb4 and maya 2011

#2

Never had this trouble before but I’m having it now! I have roughed it down to the displacement maps… I am also stumped. I was wondering if there was a cure or a workaround?

V

#3

An issue has been found especially with UV normals, but the model should be visible, only the normal maps should have a flipped channel.
What happen if you force a double side render? (Sorry, I’m not a Maya expert)

#4

Just bumped into this problem myself. Has anyone been able to find a solution? I checked over my process a few times and followed the instructions correctly, but I must be missing something. Render stats are fine, lighting the scene obviously doesn’t solve it, redoing the UV’s in zbrush failed to fix it also. mental ray just won’t read the Goz object, it’s treating it as nothing! I wouldn’t be surprised if it were a one click solution that’s hiding somewhere. How annoying, it makes no sense right now.

Anyone??

#5

Got it!

For me the problem was bad tessellation, or bad geometry, around the feet of my character. Mental Ray got confused and just dropped the whole model and rendered black. This I’m guessing happened because I started modeling with Zspheres and went about it incorrectly. Once I fixed the problematic areas in Maya, the model rendered fine.

Hope this helps!

Ofer

#6

If you guys retopologized the mesh in another software and imported it back in check if there are holes and bad polygons in zbrush. Because sometimes zbrush does not display bad polygons and ignore them. When you use goz to put the mesh in maya, max or whatever you will see those polygons again. They might look ok but thats the reason why mental ray is not rendering. So go back to the retopo software you are using and adjust the topology or if those bad polygons are in hidden places get rid of them and it will render again.

#7

I also had this issue. After messing round for a while, I found the simple fix.
Duplicate the mesh. Thats all I had to do. Duplicate, delete the original mesh and it was done!