Re: tablet touchscreen configuration

[Carlos Garnacho <carlosg gnome org>]

Hi Bruce!,

On lun, 2014-02-24 at 21:35 -0800, Bruce Perens wrote:
> Hi folks,
>
> Is there a mailing list for tablet issues or tablet developers? I
> didn't see one. Indeed the mailing lists that aren't for developers
> seem to be for specific applications rather than the system itself.
> So, please forgive me if this is misplaced.

It is true that there is no specific ML around touch/tablet support,
most activity happens in the wider desktop-devel-list gnome org , or on
specific clutter/gtk+ mailing lists.

> I've set up Gnome 3 from Debian unstable on a Panasonic Toughpad
> FZ-G1. This has two sensor surfaces on the screen: a stylus that is or
> emulates a Wacom, and an eGalaxy Touch which is a multitouch finger
> touchscreen. Both are using evdev, the eGalaxy also has mtdev. Kernel
> is 3.14 .
>
> If anyone has tested this device with Gnome or indeed Linux, there
> isn't any web evidence. It works, with a few little issues that I am
> now running down.
>
> The Wacom works correctly. The eGalaxy Touch mostly works, but
> something is different about the button events. On the screen
> keyboard, the buttons highlight when I touch them but they don't act
> as if they've been pressed. This also happens on all of the shell
> panel buttons. But finger-touch on a dock icon correctly launches the
> program.

This was a known bug in gnome-shell 3.8, which is fixed in gnome-shell
3.10.

> In xev, button press and release events look identical between the two
> devices.

xev reports legacy events that toolkits don't use that much anymore
nowadays... "xinput test-xi2" will report the more modern events that
gnome-shell and gtk+ applications see, XI_TouchBegin/Update/End between
those, it is the interpretation of those what was causing the trouble
here.

> Nice to see that Gnome 3 is mostly usable on tablets. I can probably
> test multitouch when I get through this issue.

That's something that's improving over the late/future release
cycles :). Unfortunately, this also means that having the latest and
greatest would help in testing here...

Cheers,
  Carlos