UV Smoothing

[Steffen Dünner]

Hi there

is there a UV smoothing mode in V-Ray for MODO that matches the results of MODO's UV smoothing?
I'd like to use the "ignore MODO subdvision" switch to use V-Ray's subdivisions only but UVs are getting stretched no matter what combination of options I use.

MODO Subdivisions:



V-Ray Subdvisions:



V-Ray OpenSubDiv:



Cheers
Steffen

[vladimir.nedev]

The problem is most likely the topology of the UV space in the mesh exported by V-Ray for MODO.
Basically when we get the UV coordinates of a vertex from MODO, we don't know how it is connected to other vertices in UV space.
So each polygon in the mesh becomes a separate "island" in UV space, which of course gets subdivided incorrectly.
I wonder why the V-Ray subdivision seems to work though.

We ran into this problem in V-Ray for Blender and it is possible to reconstruct the UV topology in most cases.
I don't think there is a way to get it from the MODO API directly. The reconstruction might make the export a little
slower though.

Can you attach this mesh so I can test with it ?

Greetings,
Vladimir Nedev

[Steffen Dünner]

Ah I remember that problem / feature from another bug report (with vector displacements IIRC).
Sadly I can't send you this exact mesh, as it's being used in production at the moment (although not in MODO and not in V-Ray). I was just playing around with it and noticed that I couldn't match the UVs.
The mesh itself is nothing too fancy. A simple version of it with a relaxed planar projection for the inner and outer surface should lead to similar results.

Thanks
Steffen

[vladimir.nedev]

Can you try your scene with the next nightly build from 2015-04-29 ?
This problem should be fixed in there.

Greetings,
Vladimir Nedev

[Steffen Dünner]

Wow! Nice to hear.

The project this asset was used on is long gone and archived, but I will give UV smoothing a special try ASAP.

Thanks
Steffen