[RFC wayland-protocols] Color management protocol

[Graeme Gill]

Niels Ole Salscheider wrote:
> Am Donnerstag, 8. Dezember 2016, 15:51:12 CET schrieb Graeme Gill:

>> Looking through the current Wayland color-management protocol
>> proposal, I think it is missing a really fundamental thing -
>> managing the output device color calibration state and color
>> profile. I guess the assumption is that this is being done
>> by colord, but my understanding is that colord is specific
>> to Gnome based systems, and certainly depends on DBus, which
>> Wayland does not. [ Please correct me if I've got any of this wrong. ]

> It is (currently) up to the compositor to decide how to implement this. The 
> compositor could come with its own settings for the output color profiles or 
> query some other program. This might be colord, but it could also be 
> kolormanager, or something else.

1) This doesn't address how this information is communicated
   to a Wayland application.

2) Expecting color management applications to deal with
   configuring the compositor in a platform dependent
   way, is expecting far too much. I for one am not
   about to add multiple platform dependent back
   ends (multiple flavors of Linux, BSD's, Android,
   etc.) to my tools to do this, and no other major
   platform expects it (i.e. none of MSWindows, OS X
   or X11 based systems have this requirement.)

The correct approach to avoiding such issues is simply
to make both aspects Wayland (extension) protocols, so
that Wayland color management and color sensitive applications
have the potential to work across all Wayland systems,
rather than being at best balkanized, or at worst, not
supported.

Graeme Gill.