HDR support in Wayland/Weston

[Michel Dänzer]

On 2019-03-07 10:07 p.m., Graeme Gill wrote:
> Michel Dänzer wrote:
> 
>> Yep. The alternative is that the different mechanisms clobber the
>> hardware LUT from each other, which sucks from a user POV.
> 
> Which user though ?
> 
> It certainly does the opposite of suck if you are a user
> who wants reliable color management, and so want a simple
> and direct mechanism to set the post frame buffer manipulation
> to a known state.
> 
> What does suck if you are a color critical user is that
> what used to be a reliable system (i.e. "run the profile
> loader") just became unreliable due to a system update.

It was never reliable for that. Other clients using any of those
mechanisms could always interfere, at least for the RandR compatibility
output.

> From this perspective I'm puzzled as to why such a change
> was implemented.

To make all these mechanisms work reliably and consistently at all times.


>> Welcome to
>> the wonderful world of "colour management" in X, please pick your
>> poison. I guess you can see why Wayland has a different design. :)
> 
> X11 has only got that way with such changes in behavior. It's
> been pretty reliable up to now, and at least is possible
> thanks to some foresight on the designers and implementer s part.

If you have specific suggestions, please post them to the xorg-devel
mailing lists or create a merge request at
https://gitlab.freedesktop.org/xorg/xserver/merge_requests .


-- 
Earthling Michel Dänzer               |              https://www.amd.com
Libre software enthusiast             |             Mesa and X developer