On Wed, Mar 13, 2013 at 02:18:26PM +1000, Peter Hutterer wrote: > On Tue, Mar 12, 2013 at 12:53:33PM -0700, Paul Vojta wrote: > > Dear all: > > > > I've been working on adding "smooth scrolling" to xdvi (after a long > > hiatus), and I'm encountering some glitches when switching pointer devices. > > > > Specifically, when a slave is being switched back on, the scroll valuators > > are always reported as having value 0 in the classes field of the > > XIDeviceChanged event. > > > > When using the evdev driver, however, the valuator values are the same > > as when the device was last used, and so this causes a large scroll > > glitch when resuming using the device. (When using the synaptics driver, > > the values are always reset, so there is no problem in that case.) > > (I'm only checking the vertical scroll valuator so far, but I expect > > that the same would be true for the horizontal scroll valuator.) > > unfortunately, that is the correct behaviour > http://who-t.blogspot.com.au/2012/06/xi-21-protocol-design-issues.html > > the reset should not happen in synaptics, that's likely a bug in the driver.
No, it's not the problem with leaving, scrolling elsewhere, and then re-entering a window. I've encountered and (imperfectly) dealt with that problem already. Rather, it's a problem with SlaveSwitch. It can happen even if the pointer never leaves the window. In more detail: I have my laptop's built-in Synaptics touchpad (with the synaptics driver), and an external USB mouse (Cirque USB GlidePoint, 0488:0022) (with the evdev driver -- it behaves just like a normal mouse, except that it doesn't cause a SlaveSwitch every time I jiggle the table). I can start up xdvi, move the pointer into the window, scroll down with the external (Cirque) mouse, switch to the built-in touchpad, resume using the external mouse, and then when I scroll the mouse with it I get a huge scroll effect instead of just one click. There *is* a place in the SlaveSwitch XI2-event for a valuator value, but it's always zero. --Paul Vojta, vo...@math.berkeley.edu _______________________________________________ xorg@lists.x.org: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: http://lists.x.org/mailman/listinfo/xorg Your subscription address: arch...@mail-archive.com