Tablets with GIMP

[Peter Hutterer]

On Sat, Nov 20, 2010 at 10:53:52PM -0800, Neil Whelchel wrote:
> I have been trying to get a VisTablet working with the GIMP with limited 
> success. I am not interested in the tablet acting as a core pointer so
> I added a section to the xorg configuration:
> 
> Section "InputClass"
>         Identifier "evdev tablet"
>         MatchVendor "WALTOP"
>         MatchDevicePath "/dev/input/event*"
>         Option "SendCoreEvents" "false"
>         Driver "evdev"
> EndSection
> 
> And in the GIMP extended input device configuration  I selected the tablet 
> device and set its mode to window.
> At first glance all worked as expected, then I ran into a problem...
> If I center a small drawing window in the middle of my screen, and start 
> drawing in the middle, all is fine, and I can draw to the edges, however, if I 
> start from a corner, the GIMP doesn't see the events from the tablet.
> My guess is that xorg assumes that the coordinates from the tablet corners are 
> outside of the GIMP window and does not send events. This looks like a bug, 
> because if I start in the middle, and go to the edge, all is fine until I 
> release the pen.

gimp grabs the device when a button press is registered on the canvas, but
does not do so for events outside the canvas (well, because it wouldn't get
them since they don't arrive on the canvas)

http://who-t.blogspot.com/2010/11/high-level-overview-of-grabs.html

> Another problem is that I am unable to find any real documentation on 
> InputClass. All I can find is bits here and there. Am I looking in the wrong 
> places or do I need to take on a documentation project?

xorg.conf(5) isn't enough?

Cheers,
  Peter