objects with opacity in materials doesn't work with render mask mode and fog

[frodopytlicek]

Hello,
we found another issue.

How to reproduce:
1) add vray fog
2) apply some material with opacity on some scene objects
3) use render mask to render any object

Outcome:
Visible fog on objects which sould not be visible.

[hermit.crab]

Are you sure the side teapots are not leftovers from previous renders? Does it happen if you set "Previous Render" (Settings>System) to "Clear"? Could you attach the scene, because I cannot reproduce it?

[frodopytlicek]

I didnt explaint it well propably sorry. Here is example scene.
I leave description inside the file but Ill put it here too.

- there is thick green fog to make it more visible
- big teapot is masked by layer
- small teapots are visible outide mask,
but as you can see only the parts in fog,
so its combination of fog and opacity
- increasing max transparency doesnt help

[hermit.crab]

Okay, my fog was not thick enough - it's reproducible. I've logged it (internal tracker ID: VMAX-14875) for dev investigation. You can workaround it by increasing the fog distance and (if little artifacts appear) setting the opacity mode of the VRayMtl to "Clip".

[frodopytlicek]

We cannot change fog distance because it will change the look and setting up clip by itself doesnt help. So I hope for a quick fix