[Development] Removing Wacom support in Qt5

[Shawn Rutledge]

On 10 September 2012 12:58, Shaw Andy <Andy.Shaw at digia.com> wrote:

> To clarify, I did the patch that everyone is referring to, I actually did it in my Nokia days when I had access to the tablet and passed it on to someone after I joined Digia.  It is a hack because I had to try and get around the mouse position problem, I tried then to figure out how to do it properly so it could be submitted at the time but was unable to do so.  Since I guess the tablet is going to end up back in Digia hands (assuming someone knows where it is in the Oslo office) I am willing to look at this again but would prefer someone who could help on this side of things as my knowledge of the tablet side is limited at best and I couldn't find out where the information needed was actually being stored.  If I could get that information I think I could solve the rest.  Again assuming the tablet is still around and usable somewhere :)

I grabbed the Intuos 3, it's still around.  And I can reproduce the
bug that with Qt 4.x apps (even the latest Creator released) it's not
usually possible to interact with most QWidgets using the Wacom mouse.
 (The stylus has gone missing for the moment but I think we will find
it, and I also have an old Cintiq at home so maybe the stylus is
compatible).  Whereas with Qt 5, Thiago's explanation makes sense, it
works OK as a simple mouse because there is no specific support for
it.

So now I'm trying to understand how it worked in Qt 4 and what the
right way forward ought to be.  I see that there are two choices:
wintab32.dll which is provided by Wacom, that is what Qt 4 links
against; and the RealTimeStylus class provided in the Windows SDK,
which in theory ought to be more portable to other types of tablet
PCs.  So I wonder if there is any reason we shouldn't use that for Qt
5?  Of course it may be a dumb question if too many features are
missing (we have 2-axis pressure, 2-axis tilt and rotation, so I hope
most of the data is there in the MS events, when the device reports
it?)  There is a commercial program called ArtRage which apparently
uses either or both drivers (you can choose them in the app settings).
 Users report that wintab doesn't provide gesture support, and the
reports are mixed about whether RTS provides pressure.

It's interesting that the first example I tried from Wacom confines
the mouse to the window.  Probably not what we want Qt doing by
default, so maybe that's the reason we needed a full-screen invisible
window?  Just guessing.

I'm not normally a Windows guy, so if you know how to really fix this,
maybe you will get it done faster than I will.  I just figured maybe I
should have a quick look to see how feasible it is to fix this bug.