Client: Add basic support for tablet-unstable-v2

[ChangeLog][QPA plugin] Added support for drawing tablets through the
tablet-unstable-v2 protocol.

Adds support for the basic one tablet, one tool, no pads scenario.

Besides the auto tests, I tested with a Huion Kamvas Pro 16 with a simple
pressure sensitive pen with two buttons. As far as I can tell, it works the
same way as on xcb on Sway and Gnome Shell.

Also tested on a Wacom PTZ-630 with a mouse, art pen, airbrush and a stylus.

Mapped the distance event to QTabletEvent::Z and slider to
QTabletEvent::tangentialPressure.

For now we send QTabletEvents even when there's a mouse or finger on the
tablet. Those should ideally be sent as QMouseEvents/QTouchEvents, but that's
out of scope for this patch, but at least we will send synthesized mouse events
if the tablet events are not accepted.

Change-Id: I93291ffa5f00fa2bb8533eddd8d873b84a3386b8
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

1 files changed, 5 insertions, 0 deletions

diff --git a/src/client/qwaylandinputdevice_p.h b/src/client/qwaylandinputdevice_p.h
index 87f8559c4..448d0fce5 100644
--- a/src/client/qwaylandinputdevice_p.h
+++ b/src/client/qwaylandinputdevice_p.h
@@ -89,6 +89,7 @@ class QWaylandDisplay;
 #if QT_CONFIG(wayland_client_primary_selection)
 class QWaylandPrimarySelectionDeviceV1;
 #endif
+class QWaylandTabletSeatV2;
 class QWaylandTextInput;
 #if QT_CONFIG(cursor)
 class QWaylandCursorTheme;
@@ -127,6 +128,9 @@ public:
     QWaylandPrimarySelectionDeviceV1 *primarySelectionDevice() const;
 #endif
 
+    void setTabletSeat(QWaylandTabletSeatV2 *tabletSeat);
+    QWaylandTabletSeatV2* tabletSeat() const;
+
     void setTextInput(QWaylandTextInput *textInput);
     QWaylandTextInput *textInput() const;
 
@@ -183,6 +187,7 @@ private:
     Touch *mTouch = nullptr;
 
     QScopedPointer<QWaylandTextInput> mTextInput;
+    QScopedPointer<QWaylandTabletSeatV2> mTabletSeat;
 
     uint32_t mTime = 0;
     uint32_t mSerial = 0;