I have a rare occurance of a Maya .obj not importing correctly into Zbrush - the normals are flipped. I did all the usual sanity checks: make sure that the normals are facing the right way in Maya, freeze transformations and clean up the polygons before I export etc. To top it off, the obj imports fine into other packages, with the normals pointing out of it correctly.
Any suggestions how I can fix this? Is there an option in Zbrush to flip face orientation of a tool?
Did you try Tool>Display Properties>Flip ?
Thanks, that fixes the problem inside ZBrush and I can detail the model. Unfortunately I’ll get problems when I try to create a normalmap for the mesh, because I can’t simply reimport the low-res model over SubDiv level 1. The normals will be facing the wrong way again, and I can’t flip the normals this time.
Exporting the tool to .obj from ZBrush doesn’t seem to do the trick (normals will be facing the wrong way), and I don’t think you can import a .ztl tool over the lowest subD level, can you?
I’m having the same problem, did you figure out how to solve it?
Can you try and flip the UV map in Maya horizontally and export again? Does that solve the polygon normals in Zbrush?
I have a feeling the vertice order of the UV map is used in Zbrush when calculating the normal. There was a thread a while back regarding maya, normal maps and a couple of flipped polygons, as far as I remember. Cannot find the thread right now. Will have a look tomorrow
I just tried flipping the UV’s (I’m actually using Max, but I dont think thats really important) and it didn’t do a thing. The thing that is the most frustrating is that I have multiple objects that I’ve been working on ans only a few do this, oddly enough its the ones that are cage like(imagine a cup with no bottom on it and lotsa holes on the sides)
I just figured out how to work around the problem. Originally I was using the “flip” (tool>display properties>flip) tool in ZBrush to fix the problem with the normal, but when i tried to create a normal map i was running to major problems. If you use the “double sided” (tool>display properties>double) tool instead, you will be able to create your normal maps without all the problems.
Hmmm. Well that blows my theory out of the water. Could you post an .OBJ that shows this behaviour. Or maybe you should wait until somebody with an answer comes along.
If you post an .OBJ I will first be able to look at it tomorrow.
Edit: Good to see you solved the problem. BTW, I sent you a PM.