Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: andregonweb on 2021-09-20, 15:05:02

Title: Mesh/UVW or Material problem
Post by: andregonweb on 2021-09-20, 15:05:02
Hi all,

I'm having a slight issue with a file I have had in my pipeline a short while (over multiple versions of Corona and Max).

There is a distinct seam visible directly on top of the underlying geometry (in both mutli-geo and collapsed geo setups - please see screenshots attached.)

I've tried removing UV's via the built in Max utility, exported and re-imported the mesh itself, and all to no avail.

I'd really appreciate a second pair of eyes on the problem and all of your input.

Regards -
Title: Re: Mesh/UVW or Material problem
Post by: romullus on 2021-09-20, 15:21:30
Maybe i don't know where to look at, but i don't see any issues in your screenshots. Maybe it's worth to make them more obvious, paint a big red arrow perhaps?
Title: Re: Mesh/UVW or Material problem
Post by: andregonweb on 2021-09-20, 17:00:34
Ah - yes of course.

Please see herewith where I have indicated the seam on the rendered version.

Its causing the artifacts that are making those area seam to pop out unnaturally.
Title: Re: Mesh/UVW or Material problem
Post by: maru on 2021-09-20, 17:03:19
Does this material look different in other renderers, even just Scanline? Maybe the UVW mapping itself is done like this.

It seems that those seams are appearing in places where there are some geometry edges or other objects in place. Could it be related?
If you are using displacement in this material, you can also try subdividing the mesh. Otherwise it may get pushed a little bit in the direction of the normals, which may result in some overall deformation. (compare a simple box object with displacement and no tessellation and with tessellation). 
Title: Re: Mesh/UVW or Material problem
Post by: andregonweb on 2021-09-20, 17:28:23
I didn't try that - no.

I am using displacement, and just plain old UVW Box mapping.

Also checked for geometry overlaps but there were none. However, there was a residual horizontal piece of geometry which I deleted - and it has solved the problem.

It's odd though - I can't say I have had exactly this problem before - and all the other models for this project (about 10 in total have retained their geometry and Uv's perfectly. Guess it's one to ascribe to the "corrupted geo" category.