OCIO environment variable, V-Ray 6.2

[sylk]

Hi, so did something change in the 6.2 update in regards to OCIO env. variables? In 6.01.08 everything is fine and dandy but when I installed 6.2 my whole display correction got all screwed up. Nothing shows in the dropdowns for view transform, display device and input colorspace. And I can't switch between OCIO, sRGB, ICC or None.

Tried some VfbControl() commands but they didn't seem to work either...

I had to revert back to 6.1.08 so I can't show my issues just now but maybe someone can shed some light on the situation anyway?

/Andreas

[vladimir_krastev]

Hi, thanks for posting. Here I can see a few things that are done to the OCIO support.

One bug fix: VFB 2 doesn't read the VRAY_VFB_SRGB env. variable. This environment variable did not work consistently in all 3ds Max versions and Standalone. If it did not work preciously but you still have it could be that.

A modified feature: Abort on missing OCIO display corrections. This should send a message and stop rendering if you have missing ocio config file.

And another bug fix: VFB OCIO settings lost when opening a scene with a broken config path. This is regarding the input color space, display device and view transform settings. They are kept internally until you load a ocio file or fix the missing one.

What is your case? What version of 3ds Max are you using? Do you have missing ocio config files and what environment variables did you set? Any other details that you can think of will hep us solve your issue.

[sylk]

We installed 2024.2 two days ago (and were hoping to update V-Ray to 6.2 as well). That's when I noticed the problems.

The Env. Variables we set present day:
OCIO = \\fileserver\project\ocio\3dsmax.ocio
VRAY_VFB_OCIO = 1

We used to set these too:
VRAY_VFB_OCIO_INPUT_COLORSPACE
VRAY_VFB_OCIO_DISPLAY_DEVICE
VRAY_VFB_OCIO_VIEW_TRANSFORM

That was back in V-Ray Next days. But we stopped doing that in VRay 6 because it greyed out the dropdowns so you couldn't change the view transforms while working.
So we started setting those settings via maxscript in our startup scripts. Using the VfbControl().

#ocio true
#ocioinputcolorspace "ACES - ACEScg"
#ociodisplaydevice "ACES"
#ocioviewtransform "sRGB"

I noticed now that we set (#ocio true) via VfbControl as well as via Env. Variable (VRAY_VFB_OCIO = 1). Could that have something to do with our issue?


BTW. Thanks for making ChaosScatter into an applicationplugin! Love it!


/Andreas

[vladimir_krastev]

I noticed now that we set (#ocio true) via VfbControl as well as via Env. Variable (VRAY_VFB_OCIO = 1). Could that have something to do with our issue?

This will grey out the None/sRGB/Gamma2.2/OCIO selector and will leave it in OCIO mode.

But we stopped doing that in VRay 6 because it greyed out the dropdowns so you couldn't change the view transforms while working

This does not happen on my end with environment variables.

We used to set these too:
VRAY_VFB_OCIO_INPUT_COLORSPACE
VRAY_VFB_OCIO_DISPLAY_DEVICE
VRAY_VFB_OCIO_VIEW_TRANSFORM

What values are you using for them?

[sylk]

This will grey out the None/sRGB/Gamma2.2/OCIO selector and will leave it in OCIO mode.

Ok, from the help files I got the feeling that it just checks the OCIO radiobutton. Not that it disables the whole selector UI. Seems excessive? But ok.

This does not happen on my end with environment variables.

Ok, interesting. We first got issues when moving from V-Ray Next to 6.0. I made a post about it back in the day. OCIO environment variable - Chaos Forums
We got around it by not using those three env.variables and making the settings via startup script instead. Using VfbControl().

What values are you using for them? In my test I used values of 1.

We had those set to string values, like this:
VRAY_VFB_OCIO_INPUT_COLORSPACE = "ACES - ACEScg"
VRAY_VFB_OCIO_DISPLAY_DEVICE = "ACES"
VRAY_VFB_OCIO_VIEW_TRANSFORM = "sRGB"

snippet from the help docs:

set VRAY_VFB_OCIO_INPUT_COLORSPACE=ACEScg
set VRAY_VFB_OCIO_DISPLAY_DEVICE=sRGB
set VRAY_VFB_OCIO_VIEW_TRANSFORM=ACES 1.0 - SDR Video

But like I said, we don't use those env.variables anymore since it locked the dropdowns in the VFB and we switched to setting those values via startup scipts instead. Via VfbControl().

However in 6.2 that didn't work either...

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Could the issue arise from not using OCIO 2.x? I believe we are still on the 1.x versions with LUTs and what not.


/Andreas

[vladimir_krastev]

we don't use those env.variables anymore since it locked the dropdowns in the VFB

This is intentional. If you have set an environment variable you should not use the dropdowns.

snippet from the help docs:

Yes this is the correct values and with them the dropdowns should be grayed out. I made a mistake in my test and this is why the dropdowns were accessible.