On Thu, Oct 15, 2015 at 09:45:56AM +0100, Daniel Stone wrote: > Hi, > > On 15 October 2015 at 09:32, Jonas Ådahl <jad...@gmail.com> wrote: > > On Thu, Oct 15, 2015 at 09:16:14AM +0100, Daniel Stone wrote: > >> On 15 October 2015 at 04:56, Jonas Ådahl <jad...@gmail.com> wrote: > >> > On Thu, Oct 08, 2015 at 12:15:10PM -0500, Derek Foreman wrote: > >> >> Perhaps I should read what's in phabricator before I continue to > >> >> comment, though. > >> > > >> > Hmm. I can't find it any more. It was in the fdo phabricator task > >> > <https://phabricator.freedesktop.org/T1> but all those comments are no > >> > longer there. I have no idea why. > >> > >> Hmm, is it in the individual commits for review? > >> > >> e.g. https://phabricator.freedesktop.org/D13 > > > > "You Shall Not Pass: Restricted Differential Revision" > > Oops. Given that was the first revision (D1!) ever in there, it was > against an old repository import that I later junked. Phabricator got > confused since it partly inherits the permission from the repository - > fixed now. As you can probably guess from all the spam in your inbox > ... > > >> > I wonder if we should put "wl_double_fixed" in wayland/ and declare that > >> > an "official mutli part type" thing so we don't have to reimplement the > >> > awkward from/to functions all over the place. Maybe even > >> > a wl_double_fixed_t type as was suggested at an earlier point? > >> > >> I'm still a bit uneasy on the actual need for this: wl_fixed_t gives > >> us 1/256th-pixel precision. Is that not enough? Surely changes less > >> than that cannot affect the viewport, so why would we spam clients > >> with them rather than accumulating internally and sending when it > >> passes the threshold? Is it just about implementing acceleration on > >> the client side? > > > > For absolute motions I agree. For relative, I don't know. I'm no high > > end gaming device expert (or where high precision might be relevant) > > There were discussions about this before that resulted in changing > > from ms to us timestamps and from 32 bit to 64 bit fixed for deltas, > > because we didn't want to pretend to be sure that the precision we had > > was definitely enough for all relative pointer use cases. > > Ack, fair enough. Anyone?
mostly thinking aloud here: The precision that humans can consciously control a mouse with is very high. Whether 24.8 is insufficient for *us*, I'm not sure. Maybe leave it at wl_fixed_t for now and figure out a transition plan for making this a latched event in the style of the wl_pointer.axis_discrete proposal, if we ever need it? i'd stick with the 64-bit timestamps though, we know we have devices out there that exceed the current granularity. Cheers, Peter _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/wayland-devel