[RFC wayland-protocols] Color management protocol

[Graeme Gill]

Kai-Uwe wrote:

> Maybe the device link is kind of a extension for later implementation.

I'm not enthused by that - I'd rather have it there right from the
start if no other practical means of an application doing the
color conversion itself. To do otherwise means that it will never be
uniformly supported, and relegates Wayland to being second class for
color critical applications.

In terms of the compositor support needed, I don't see it as adding
any significant extra complexity - the processing needed is simpler
in many ways to the device profile case - no linking is needed.
There is just a little extra book keeping in storing one
device link per Output, and using it in preference to the
device profile if it is present.

One of my concerns about this approach is whether it limits the
precision of the conversion in ways that do not apply if
the application is able to do the conversion. HDR is arriving,
so this could be important if it turns out that current
ICC V2 and V4 is insufficient in some way. ICC Max is
too immature at the moment to write into a spec., although
it is moving along. (The presentations at ICC DevCon in
San Diego were interesting from that point of view.)

Graeme Gill.