Bug?: Alpha transparency close to another surface issue.

[seanlo]

Hello,

While using the genesis 8 character, i have two different surfaces X &Y set to very close distances (0.01 cm).
Surface X is the body.
Surface Y is a shell.
The shell has a alpha transparency associated with it. Where it is fully transparent, octane render renders through surface X & Y.
Ray epsilon is set to the minimal value of 0.000001.

The issue is resolved if i set surface Y to distances of 1 CM or greater. However, the realism of my rendered image drops significantly.

Thanks.

[face_off]

Hi - this is due the the Kernel->Ray Epsilon being to large, resulting in close vertices causing artifacts.

Paul

[seanlo]

Hi - this is due the the Kernel->Ray Epsilon being to large, resulting in close vertices causing artifacts.

Paul

Hi Paul,

Is there a workaround?

As i mentioned in my previous post, I have already set Ray epsilon to the minimum of 0.000001.
I have to set surfaces to > 1 CM which reduces the realism of my renders.

[face_off]

A Ray Epsilon of 0.000001 means you should be able to have your vertices a fraction of a millimeter apart. Is it possible the scene units are incorrect? Or there is another geometry item interfering?

Paul

[seanlo]

A Ray Epsilon of 0.000001 means you should be able to have your vertices a fraction of a millimeter apart. Is it possible the scene units are incorrect? Or there is another geometry item interfering?

Paul

It appears that this body prop I am using creates a geometry shell attached to Genesis 8.
The body prop then clashes with this geometry shell which causes an interference.
If i reattach the geometry shell to this body prop, there is no collision but there is an ugly artifact floating on top of the skin.

Oddly enough, there is no issue with iray when this is rendered.

[valzheimer]

When using geoshells with Octane (and sometimes Iray if geoshells were created for previous renders) you have to set offset higher, set it to 0.1 for an example to avoid interference.
Same goes with some hairs if you get artefacts from the cap of the hair, simply use the morph to enlargen head size if available or go to the head bone and up by a few percent so that cap doesn't clash with the model.

[seanlo]

Looks like this issue is still not fixed..

To be frank, it seems silly that a 100% transparent shell would clash with the object below it. Can't you implement a quick fix to completely remove 100% transparent shells from even rendering? This is causing a huge amount of artifacts that i am temporarily resolving by attaching magnets to pull the 100% transparent shells away from the surfaces.