ID 464540 - Nuke does not load a custom LUTs inverse look correctly if it is not in the first display set of the config.ocio file

Problem summary
Within Nuke it is possible to load one or more custom 'looks' (color transforms) from an OCIO config file, as selectable Viewer Processes within the Viewer.

 

In addition to a standard look, it is also possible to load an inverted look to negate the LUT at a later point in time.

 

It has been discovered that if an inverted look is not in the first display set (default), then this inverted look will not be correctly loaded within the Nuke Viewer.

 

Note: While this appeared to be resolved within the Nuke 12.0v1 release, it still does occur when the config.ocio is reloaded.

Customer reported version
nuke.11.3v6

Customer reported platform
centos7

Steps to reproduce

1) Within a Nuke 12 session, load an OCIO config that contains the 'default' display set and an additional display set, with each containing a look and inverted look (example attached)

 

2) Create a Colorwheel node

3) View the results of the 'default' look and its inverted look on the Colorwheel node by selecting them within the Viewer Process drop down

 

4) View the results of any additional looks and their inverted looks on the Colorwheel node by selecting them within the Viewer Process drop down

Result: Correct results

5) Reload the OCIO config through the Project Settings, and repeat steps 3 and 4
Result: Any looks that are not the first display set have the incorrect result.

Expected behaviour
When reloading the OCIO config, any additional looks and the inverted looks should transform as per the first display set

Actual behaviour
Reloading the OCIO config causes the inverted looks of additional display sets to not be applied correctly.

Workaround
As an alternative it is possible to apply the inverted look via the OCIOLookTransform node, as long as the OCIO config is loaded.

Reproduced by support
This bug has been reproduced in:
Nuke 12.2v4 - Windows 10, CentOS 7, MacOS 10.15.6
Nuke 12.2v1 - Windows 10
Nuke 12.1v1 - Windows 10
Nuke 12.0v1 - Windows 10

Nuke 11.3v1 - Windows 10

Nuke 11.2v1 - Windows 10

Nuke 11.1v1 - Windows 10

Nuke 11.0v1 - Windows 10

Nuke 10.5v1 - Windows 10

Nuke 10.0v1 - Windows 10

Nuke 9.0v1 - Windows 10

Earliest version tested
Nuke 9.0v1
- Occurs in all Nuke regressive testing versions