OBJ UV ok in Marmoset, NOT ok in C4D


#1

Hey so I have a very annoying problem in C4D that I don’t seem to find the solution to, since I’m not even sure what is the problem.
So I have a model given to me by a modeler, it’s an OBJ with UV coordinates and a normal map. No matter what I do, the normal map shows where the seam is on the back of the model in C4D. When I import the model to marmoset with the same normal map, there is no seam. However in C4D it just gives a weird distortion, I can’t even explain it, because the texture seem to continue smoothly, it’s just that something becomes off once it gets to the seem.
I tried inverting all channels, tried to mess with in the UV editor, re-export the OBJ as .DAE, but the seam is still there.
Please does anybody have an idea whats going on here?

This project is long over-due so I really need to fix this already, I tried many things and this is one of my last resorts.

Here are some examples of the issue:
The UV issue (there’s a similar one in the front too:

In Marmoset, no issue there:

How it looks with texture in Arnold:


Here’s the UV map in C4D and the Normal Map:


I would really, really appreciate some help here, I’m desperate.
Thank you!


#2

My guess is that the polygon normals aren’t aligned consistently. Looks like some are flipped the wrong way.

If not that then the Vertex Normals aren’t consistently applied.

If it was created in an AutoDesk program then they have what are called “Smoothing Groups”. C4d works a bit differently.

If the problem is the Vertex Normals I suggest you purchase a cheap little plugin called, “VERTEX NORMAL TOOL PLUGIN”

The help section shows how to use the tool to fix a very similar situation. See this page!!!


#3

HEy IceCaveMan, thanks for your reply.
The Vertex Normal consistency problem really seemed like it could be it, bought the plugin and tried what it says in the tutorial as well as different variations on it and just tried different options in the plugin, but unfortunately nothing seems to work, the seam is still showing. When I apply the “Average Vertex” they all seem to align, but the texture still comes out chopped. Doesn’t matter if I render it in Physical Renderer or Arnold Renderer.

God this is SOOOO frustrating.
Here’s the OBJ and the Normal Map, if anyone wants to take a look at them, maybe I’m missing something completely obvious. I really appreciate anyone who takes their time to help with this, I’m all out of ideas.

LP2(1).obj (2.1 MB)
Jacket__normal.psd (41.8 MB)


#4

It looks like whatever is generating/exporting your Normal Map is doing a bad job.

I did a very quick test of basic fixing of the Normal Map using Photoshop and those areas are highlighted in yellow circles. The C4D screens show where on the map I worked and what the difference under the left arm of the jacket looks like once that has changed. It seems the be where the issues lays. I hope it’s at least some help for finding a fix.


#5

Different Programs have different formulas for how to encode and decode normal maps. I’d play around with how c4d is decoding the normal maps.

Normals_Orient

Either the normal method/flip should do it…or go back to the manual for Vertex Tool plugin.


#6

I tested all that, both on Import of the .OBJ and in Material Editor before I altered the Photoshop file as a quick test. I also viewed the Vertex Normals using Viewport>Options>Vertex Normals and they seem to point the correct way, at least where I was testing.

I may be wrong, but in this instance it seems to only be incorrect in certain spots so, for instance, flipping Tangents will only change the problem, not fix it.


#7

Thank you both! IceCave, I definitely tried every one of these, and like Drew said it changed the normal orientation of the whole jacket, not just in those seams.

Drew thank you SO MUCH! You’re awesome for taking a jab at it, I really appreciate it.
So did you basically just clone stamp/purple paint over those janky edges?


#8

Yes, that’s exactly what I did. Obviously I did it quickly to test if it resolved the issue, but it shows that the map itself is not good.

If it works in Marmoset, is it possible to export that Normal Map from there to test if it’s different?


#9

Not sure how to export it from Marmoset, I just import the OBJ and the normal map into it and see how it looks, I actually just downloaded it for that purpose to see the differences, beyond that I’ve never touched that software…

I’ll try cleaning the UV map manually and check it, thanks again buddy.


#10

I took a look and the UVs could be better on the TopBack of the Jacket, it’s pinched on the left side which affects the sharpness of the stitch in the area where the UV island break is. Also the seam cuts right between TopBack and TopBottom of the Jacket which doesn’t help. I can also the see the seam in your Marmoset image. The normal map doesn’t have a chance with that UV layout.


#11

Also, a lot of your UV space is being used up by inner polygons. Shrink 'em to make room for reworked outer polys and get the most resolution for normal detail.


#12

Thank you all for your responses, I ended up exporting the model from Marmoset, and for some reason it fixed the UV issues, however now the model quadpolys got triangulated, which kinda sucks but at least it does look as bad.