On Fri, Oct 30, 2015 at 08:33:16AM +0000, Daniel Stone wrote: > Hi, > > On 30 October 2015 at 04:27, Jonas Ådahl <[email protected]> wrote: > > On Fri, Oct 30, 2015 at 08:41:18AM +1000, Peter Hutterer wrote: > >> On Thu, Oct 29, 2015 at 09:33:14AM +0000, Daniel Stone wrote: > >> > Right, so I think we agree here. I'd prefer to keep the types matching > >> > as well; I do struggle to see how wl_fixed_t isn't sufficient, but on > >> > the other hand am not entirely sure I care enough about it, so am > >> > happy with whichever. Keeping it purely raw might in fact just be > >> > easier for everyone. > >> > >> fwiw, I still read this bug as an issue of timestamp granularity, not > >> motion > >> granularity. unless I'm missing this, I can't find anything that says the > >> deltas themselves are insufficient. > >> > >> and deltas are just that - device-specific deltas, and the raw motion isn't > >> accelerated or normalized, so even a 8200 dpi mouse will give you a delta > >> of > >> 1/1 for the minimal movement. > >> Even if we normalize those down to 1000dpi, the minimum delta is ca 1/8, > >> and > >> wl_fixed_t granularity is 1/256, right? > > > > That is true. Where we might have even smaller values would be if we > > normalize to 1000dpi and apply pointer deceleration, but then we still > > wouldn't end up with such small values because usually the smallest > > factor we decelerate with is 0.3, meaning we still wouldn't end up with > > that small deltas. We discussed this on IRC, and after your > > explanations, I think we could just as well just use wl_fixed_t. If > > there would be acceleration profiles that decelerate even more (for > > example 0.03 instead of 0.3 on a 8200dpi mouse normalized to 1000dpi), > > then since the resulting delta doesn't really represent a hardware event > > anyway, accumulating the leftover fraction isn't that big of a deal. > > Daniel, what do you think? > > Right, that makes sense to me. Though in the raw case, surely > deceleration won't be applied?
Right. At least not in weston/libinput. What "unaccelerated" actually means is really up to the compositor. Jonas > > Cheers, > Daniel _______________________________________________ wayland-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/wayland-devel
