[RFC wayland-protocols] Color management protocol

[Niels Ole Salscheider]

Am Donnerstag, 1. Dezember 2016, 15:17:53 CET schrieb Graeme Gill:
> Niels Ole Salscheider wrote:
> 
> Hi,
> 
> > Then they use the "set_colorspace" request
> > to set the color space of their surface to the same color space in order
> > to
> > indicate that the compositor must not perform any additional color
> > conversion.
> that's one issue I have. This is a *really bad idea*,
> based on experience with its use on Apple OS X,
> and experience in designing other color management systems.
> 
> Use an explicit "color management off" flag instead.
> That clearly indicates what is intended, is not time
> sensitive (i.e. it's meaning is the same irrespective of
> what the device profile changes to in the future),
> doesn't demand that the client, application or file have the
> ability to identify or fetch the device profile, and is not
> subject to mistakes or confusion about whether the right
> profile has been set or whether profiles match, or whether
> pixel values are really being altered or not.

The first version of my proposal had such a flag. I removed it and replaced it 
by the described version based on feedback from Zoxc (zoxc32 at gmail.com).

I can see advantages with both solutions. One advantage with the current 
proposal is that you can have a surface that covers multiple screens. In this 
case the compositor can still try its best to correct the colours for all but 
the main screen.

Back then I argued that this might not be good enough if you want to calibrate 
the monitor. But the consent was that this would require another protocol to 
disable all colour corrections anyway and that it could be developed at a 
later point.

I've CCed the list again because others might have an opinion on that...

> Cheers,
> 	Graeme Gill.