[COLOR] Provide Colourimetry options

[itsmattkc]

Issue by sobotka
Thursday Apr 30, 2020 at 18:28 GMT
Originally opened as sobotka#50

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General TODO Summary

Provide optional colourimetric overrides.

Additional Information / Notes

Not all colourimetric information is provided or available via OpenColorIO configuration files. As such, provide overrides for behaviour, such as:

• Luminance weights for certain saturation / desaturation UI.
• Colourimetric information regarding working space for nodes.