Re: [gentoo-user] Display name and Wacom tablet

[YoYo Siska]

On Sun, Nov 13, 2011 at 04:07:42PM -0500, Daniel D Jones wrote:
> I have an Nvidia GeForce GTX 560 Ti running nvidia-drivers 275.09.07.  It
> supports dual monitors via Twinview.  I have a Wacom Inspire3 6 x 8 Tablet.
> The tablet is working but it covers the entire display across both monitors
> and I'd like to restrict it to one monitor.
>
> This is supposed to be done via
>
> xsetwacom set "Wacom Intuos3 6x8 pad" MapToOutput VGA1
>
> VGA1 is supposed to be the name of the display you want to restrict it to, and
> that name is supposed to be available via xrandr.  xrandr gives me the
> following output:
>
> ddjones@kushiel ~ $ xrandr
> xrandr: Failed to get size of gamma for output default
> Screen 0: minimum 2048 x 768, current 3360 x 1050, maximum 3360 x 1050
> default connected 3360x1050+0+0 0mm x 0mm
>    3360x1050      50.0*
>    2048x768       51.0
>
>
> ddjones@kushiel ~ $ xrandr --verbose
> xrandr: Failed to get size of gamma for output default
> Screen 0: minimum 2048 x 768, current 3360 x 1050, maximum 3360 x 1050
> default connected 3360x1050+0+0 (0x166) normal (normal) 0mm x 0mm
>         Identifier: 0x165
>         Timestamp:  13703
>         Subpixel:   unknown
>         Clones:
>         CRTC:       0
>         CRTCs:      0
>         Transform:  1.000000 0.000000 0.000000
>                     0.000000 1.000000 0.000000
>                     0.000000 0.000000 1.000000
>                    filter:
>   3360x1050 (0x166)  176.4MHz *current
>         h: width  3360 start    0 end    0 total 3360 skew    0 clock
> 52.5KHz
>         v: height 1050 start    0 end    0 total 1050           clock   50.0Hz
>   2048x768 (0x167)   80.2MHz
>         h: width  2048 start    0 end    0 total 2048 skew    0 clock
> 39.2KHz
>         v: height  768 start    0 end    0 total  768           clock   51.0Hz
>
> I've tried guessing at the display name, trying VGA, DVI and LVDS with various
> numbers appended but xsetwacom simply complains that the display does not
> exist.
>
> I've also tried setting the Coordinate Transformation Matrix as described
> here:
>
> http://sourceforge.net/apps/mediawiki/linuxwacom/index.php?title=Dual_and_Multi-
> Monitor_Set_Up#Dual_Monitors
>
> I can set the matrix via the xinput command and xinput list-props for the
> device confirms that the matrix is set to the new value but it does not alter
> the behaviour of the tablet - it still spans both displays.  I set and
> confirmed the matrix for the pad, the eraser and the cursor.
>
> Any advice or suggestions on how to either either identify the display names
> (or fix whatever issue causes xrandr not to display the info) or to otherwise
> restrict the tablet to one monitor would be greatly appreciated.


Nvidia driver doesn't use the xrandr protocol when dealing with multiple
monitors... they have their own extension and they say that it is better
and that xrandr is bad, and they report through xrandr only one output
(monitor) that covers all nvidia outputs. Thhat's the 'default' output
in your xrandr output, it's widht is the sum of widhts of both monitors
etc..

They report the physicall layout of monitors through the xinerama
extension, but  I guess that wacom uses xrandr (xinerama only numbers
the display, it doesn't have names, reports only a subset of randr
information and is generally older...)

I guess your only chance is to find parameters in the wacom display that
allow you to restrict the tablet to a certain area by setting the
coordinates... (and that would ofcourse work only for a specific
resolution...)

yoyo