Back shading with bump

[flat]

With back shading with bumps, light leaks.



It can not be seen with 3ds Max or Maya GPU.



V-Ray 4.04.01 With Maya 2018 confirmed.
Probably this problem is from V-RayMaya 3.30 onwards.

Attach Test scene
qd.zip

[flat]

someone at Chaos Guy?

[damaggio]

Yeah , have the same issue , I just cover the back or add thickness to mesh.

[yolov]

I can confirm that. I wouldn't say it's a light leak, though, as it seems to be the bump itself calculated for the backside. I'm also unsure if this is normal behavior or not, so I'll need to run it through the devs before I can say anything.

[flat]

It is wonder why it can be seen only with Maya CPU Production.

[Mihail.Djurev]

We have reproduced the issue. We'll investigate why this happens and write back to you.

[flat]

This problem is obviously problematic with PolyHair and Cloth shading.

want a workaround method

Thanx

[yolov]

I can't think of anything else than what damaggio suggested. I hope it will work for you.

Yeah , have the same issue , I just cover the back or add thickness to mesh.

[flat]

Ok.

There is no solution.

Please display a warning in the V-Ray log "There is a Single Side mesh with Bump in the scene!"