Hi, On 1 February 2018 at 22:00, Derek Foreman <der...@osg.samsung.com> wrote: > On 2017-12-14 05:40 AM, Pekka Paalanen wrote: >> The 'head' member of 'struct weston_output' is going to go unused and >> then disappear, so stop using it and find a head from the proper list. >> >> However, this leaves a problem in cms-colord: if you have multiple >> monitors driver with the same CRTC, what do you say to the color >> management system? The monitors could be different, but all the color >> LUTs etc. are in the CRTC and are shared, as is the framebuffer. >> >> Do the simple hack here and just use whatever head happens to be the >> first in the list. > > I am a complete non-expert in this area, so if I'm making no sense feel free > to tell me to shut up... > > I think if someone's going through the effort to properly setup color > management, then we can't use cloned heads off a single CRTC? > > We should probably disallow a CRTCs to drive multiple heads if two or more > of those heads have differing color profiles? > > If I went to the trouble of calibrating two displays, I would probably be > extremely surprised to see them looking different with clone mode enabled.
Yeah, what Derek said. I think non-homogeneous colour properties when colour management is enabled, should be cause to unclone. That being said, it's a niche enough usecase that I'd be comfortable landing it with documentation that it was a known shortcoming. I'd be super comfortable landing it if we also had an output configuration tweak we could use to force non-clone mode, or really even just a simple out-of-tree patch (or environment variable, a la atomic?) that allows people to work around it easily enough by disabling clones. Cheers, Daniel _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/wayland-devel
