Dual monitor setup gives wrong aspect ratio

[Ramalho]

Hello,

I'm using the wizardpen with a dual monitor setup (latest drivers from PPA, via HAL/fdi).
The tablet is working smoothly -- sensitivity/buttons/mouse/Gimp/Inkscape/Blender/etc -- except for the aspect ratio along my two monitors (same size/resolution, using TwinView), i.e., when drawing circles I get ellipses instead.

I've tried playing with KeepShape ( <merge key="input.x11_options.KeepShape" type="string">on</merge> ) on the fdi file with no success. Xorg.0.log doesn't mention any KeepShape option at all.

Is there a way to make my tablet keep the aspect ratio along both monitors or restrict the tablet to one of them?

Thanks.

[Gerard Krol (gerard-)]

The wizardpen driver doesn't support KeepShape (yet?). You can try setting ScreenX and ScreenY to the resolution of the monitor you want to use. Let me know if that works.

[Gerard Krol (gerard-)]

My goal is to get a "KeepShape" option, which is enabled by default and correctly supports multiple monitors into 0.9

[Fabrice NEYRET (fabrice-neyret-inria)]

I have implemented an extention to wizardpen that exactly solved that:
I added a config flag biscreen = 0 (usual behavior) , 1 (map tablet on left screen), 2 (map tablet on right screen).

How can I integrate it in the distrib ?
These are really few lines of code, I can easily email them to somebody more responsible and aware about packaging than I am.
Mail me to Fabrice.Neyret AT inria.fr

Regards,

Fabrice

[Wladimir J. van der Laan (laanwj)]

Fabrice: can you please attach your patch here, it'd be very useful for me at least. I'd like to restrict the pen to one monitor at a time.

[Fabrice NEYRET (fabrice-neyret-inria)]

See my patch below. The code editing was easy, but I don't know anything about packaging and reinserting into community project, so it would be cool that somebody who knows do the trick. (I had multiple individual request, I guess updating the official code would be really usefull).

Fabrice

Here is the detail:

....................................................................................
I added a simple extention allowing to use dual-screen (with one single large Desktop): rather than deforming the tablet-to-desktop mapping caused by the different aspect ratio (which shows very impractical in practice), I added a configuration variable 'biscreen' which, if set to 1 or 2, only maps the tablet on the left or right screen (which fit to the common usage: one gimp on one side and the remainder on the other). Value 0 correspond to the nowaday behavior.

....................................................................................
My modifications, based on version 0.6.0.2:
....................................................................................

* wizardpen.h:
   in "struct WizardPenPrivateRec":
     ADD:

       int screenflag;

* wizardpen.c:
    in "WizardPenPreInit() ":
      right before "// increment setting"
        ADD:

    s = xf86FindOptionValue(local->options, "BiScreen");
    if (s && strlen(s) > 0) {
    priv->screenFlag = atoi(s);
    xf86Msg(X_CONFIG, "%s: BiScreen = %d\n", local->name, priv->screenFlag);

* in "USBReadInput() "
       right before "if (1)"
         ADD:

     if (priv->screenFlag) {
            report_x /= 2; /* half of the bi-screen */
            if (priv->screenFlag==2) report_x += screenInfo.screens[0]->width/2;
    }
        if (1)

* in "ConvertProc() "
     right before "return TRUE"
       ADD:
         if (priv->screenFlag) {
            *x /= 2; /* half of the bi-screen */
            if (priv->screenFlag==2) *x += screenInfo.screens[0]->width/2;
    }

* in "ReverseConvertProc () "
    right before " valuators[]= "
       ADD:
          if (priv->screenFlag) {
        if (priv->screenFlag==2) x -= screenInfo.screens[0]->width/2;
         x *= 2; /* half of the bi-screen */
      }

enjoy !

[Martin Owens (doctormo)]

Hey Fabrice, you need to make either a diff patch or a bazaar branch containing your changes.

http://developer.ubuntu.com/packaging/html/fixing-a-bug.html

[Ken Causey (bx0-ozn-zwn)]

I have the same issue with dual screens and I appreciate Fabrice's solution but I have to wonder if it isn't somewhat short-sighted. I can see a use for a much more general solution that doesn't assume simply two monitors side by side.

I'm thinking that what might be best is a set of four floating point numbers to indicate the 'percentage' of the display in each direction to which the tablet should be mapped: starting and ending x values and starting and ending y values. Each value would have a valid range of 0.0 to 1.0 where, for example an x value of 0.0 is the far left edge of the virtual screen and 1.0 is the far right.

Thoughts?