Environment Background Color override not working. Objects with single sided Materials render, but shouldn't.

[BeneZ]

Hello,
I have two issues, not sure if it has to do with the new Vray version:

1.
Environment backgound override color is not working.
I enabled in Rendersettings > Overrides > Vray Environment > Background Texture WHITE
and I enabled in the camera itself > envidonment > white color
But still the background is grey (empty)

2. I always have set my "room" set on single sided, in order to look through them at my set.
In the viewport it also works as always, but when rendering the object is not single sided and hiding my view.
What could be the reason?

3. When I try to adjust by rendering near clip plane, also here the problem: Vray does not respect the settings.
In the VP2 I can see that clipping works, but not in render.

Thanks for help

IPR render, Vray5, Maya 2020.3

[Dimitrina.Milanova]

Hello there, I am looking at this problem at the moment. Is it possible for you to send a scene, with which you are able to reproduce the bug?

Kind Regards,
Dimitrina

[BeneZ]

Hello Dimitrina.Milanova

I have prepared now a file with two cameras to recreate the problem.
It's here attached.

Thanks for investigating

[Dimitrina.Milanova]

Hello again,

In regards to the first problem, it seems that it happens when the camera is set to be Physical camera. The moment the opiton is disabled, the background goes back to white. Changing the values of any of the options for F-number, ISO or Shutter Speed should fix this problem.

Kind Regards,
Dimitrina

[BeneZ]

Thanks. I found also out, that if I set the value over 1 in the override color of environment diffuse, it gets brighter until white.
I will check that once again.
So it seems just to be seen with a physical camera as a diffuse of an standard object (sphere). I imagined that it is auto-adjusting like a surface shader which is always exposure independently.
I always use physical cameras, they were always recommended.

Let me know, if you find out something for the single-sided view.
It is by the way something I am desperately missing in 3dsMax. Especially as the main focus there is interior!

Single-sided material render would be a great feature for 3dsMax.

[Dimitrina.Milanova]

Hello again,

I have looked into all the issues you have faced throughly. The first issue, I have loged is the one for the 'Near Clip Plane' option and
you can track it with this internal bug tracker ID: VMAYA-10113.

I have forwarded the request for transparent back-side rendering to our developers to consider and loged in an issue into our system too and this is the internal bug tracker ID:VMAYA-10117.

Here is a workaround you can use for now:
Set VRay2SidedMtl to the walls, enable the Back material option and use black color for translucency. In the front material slot set your walls material.
In the back material slot set some material with black opacity. This will make back faces render transparent.

Kind Regards,
Dimitrina

[dian.nikolov]

Hello BeneZ,

Regarding the back face rendering and the single-sided option of VRayMtl:
Single-sided is not supposed to render back faces as invisible. It basically just controls whether the normals on the back faces used for shading are the same as the normals on the front faces (double sided off) or flipped (double sided on - default).
It was useful in a few specific cases which should now be covered by the thin-walled option.

From your description, it looks like you actually need some form of backface culling.
For example you can check Lele's suggestions here (hopefully not too hard to adapt from V-Ray for 3ds Max):
https://forums.chaos.com/forum/v-ray...cull-in-render

Best regards,
Dian