Hi, On 11 February 2012 15:42, Chase Douglas <[email protected]> wrote: > On 02/11/2012 11:51 AM, Daniel Stone wrote: >> On 11 February 2012 01:25, Chase Douglas <[email protected]> wrote: >>> This means we also can't emit touch events while moving the cursor. I >>> added a patch that ensures the cursor is only ever moved when one touch >>> is on the device so we can emit touch events when two touches are on the >>> device. >> >> The click case in particular is a difficult one to solve correctly. I >> guess you ultimately don't want to crush any movement which is a >> direct continuation of what came previously, but only new movement. >> You do need to stop at least some movement though, since otherwise it >> becomes near-impossible to click something accurately, as your finger >> will invariably wiggle a bit while doing the physical click. > > I believe you are getting at a different issue. I will admit that I > don't attempt to solve the issue of pointer motion while trying to click > on a button pad in this patch series. It's a problem that should be > addressed, I'm just not sure how yet. > > What Bryce was saying is when you go from one touch on the touchpad to > two, but before the button is pressed, the cursor freezes. As soon as > the button is pressed, the cursor unfreezes so you can click and drag > with two fingers. On irc, Bryce told me that he tends to leave one > finger on the buttonpad, move the pointer with another, and press the > button when he's got the cursor in the right location. That's not > possible anymore because we inhibit pointer motion when more than one > touch is on the touchpad.
Right - separate but all related - we hit this too during our clickpad work. When the second finger lands, it could be for a scroll, for a click, or for some other gesture. So perhaps one approach could be to not change state until we've definitively established what's going on - so if you've got pointer motion on going and a second finger lands, continue tracking the same finger for pointer motion until you've worked out whether it's a scroll, or a click, or a pure touch gesture. We did this to some extent with the scroll stuff, to make sure we were avoiding unwanted pointer motion when doing two-finger scrolling. Some of this stuff gets pretty worrying though; people expect to be able to do two-finger scrolling with one finger, so distinguishing between that case, and the case with one finger down for clicks and another for motion, becomes basically impossible. Cheers, Daniel _______________________________________________ [email protected]: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
