On 2020-03-11 9:09 p.m., Simon Ser wrote: > Hi all, > > I've been working on adding VRR support to Sway [1] (a Wayland > compositor). The compositor just sets the VRR_ENABLED property. > > This works fine for some screens, but causes flcikering for other > screens as expected [2]. Fixing the flickering is something we've > talked about last XDC [3]. The flickering is caused by physical > limitations of the screen: changing the refresh rate too quickly > results in brightness issues. > > The approach taken by xf86-video-amdgpu is to only enable VRR if an app > is fullscreen and not present in a special Mesa blacklist (e.g. Firefox > is in the blacklist because it doesn't render at a fixed interval). > > For Wayland, I'd prefer to avoid having a blacklist. I'd like to be > able to use VRR in the general case (not just for fullscreen apps). > A way to fix the flickering would be to implement a slew rate and make > it so refresh rate variations are capped by the slew rate. One potential issue I see with this is the cursor, which can feel awkward if it only moves at 30 Hz. I wonder if a slew rate which can reliably prevent flickering allows the framerate to ramp up quickly enough for this not to be annoying. -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and X developer _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
