QTouchEvent: add uniqueId and rotation; TUIO: support fiducial tokens

TUIO supports tracking tagged physical objects on touchscreens by
various means (QR codes, RFIDs etc.)  It can detect both position
and rotation.  Likewise, it may be possible for some touchscreens or
drivers to detect orientation of the fingers.  So, just as QTabletEvent
has rotation, each touchpoint needs to include the rotation value.

When using tokens, each object has a permanent unique ID, whereas
QTouchEvent::TouchPoint::id() is a transient ID which usually auto-
increments each time a finger is pressed to the device.  So we need to
make that available too, to identify each token.  Different platforms
may use different kinds of IDs (int, UUID, QR code etc.); however for
TUIO 1.x, the unique IDs are just 32-bit integers.  QPointerUniqueId
is added, storing only a qint64 for now (like QTabletEvent::uniqueId())
but able to be expanded as necessary later on.

Task-number: QTBUG-51844
Change-Id: I04182042f47fa2954728079139a4664a31184b54
Reviewed-by: Robin Burchell <robin.burchell@viroteck.net>

1 files changed, 22 insertions, 1 deletions

diff --git a/src/gui/kernel/qevent.h b/src/gui/kernel/qevent.h
index 1c42c61e85..785884681f 100644
--- a/src/gui/kernel/qevent.h
+++ b/src/gui/kernel/qevent.h
@@ -790,6 +790,22 @@ inline bool operator==(QKeyEvent *e, QKeySequence::StandardKey key){return (e ?
 inline bool operator==(QKeySequence::StandardKey key, QKeyEvent *e){return (e ? e->matches(key) : false);}
 #endif // QT_NO_SHORTCUT
 
+class QPointerUniqueIdPrivate;
+class Q_GUI_EXPORT QPointerUniqueId
+{
+    Q_GADGET
+    Q_PROPERTY(qint64 numeric READ numeric CONSTANT)
+public:
+    explicit QPointerUniqueId(qint64 id = -1);
+
+    qint64 numeric();
+
+private:
+    // TODO for TUIO 2, or any other type of complex token ID, a d-pointer can replace
+    // m_numericId without changing the size of this class.
+    qint64 m_numericId;
+};
+
 class QTouchEventTouchPointPrivate;
 class Q_GUI_EXPORT QTouchEvent : public QInputEvent
 {
@@ -798,7 +814,8 @@ public:
     {
     public:
         enum InfoFlag {
-            Pen  = 0x0001
+            Pen  = 0x0001,
+            Token = 0x0002
         };
 #ifndef Q_MOC_RUN
         // otherwise moc gives
@@ -824,6 +841,7 @@ public:
         { qSwap(d, other.d); }
 
         int id() const;
+        QPointerUniqueId uniqueId() const;
 
         Qt::TouchPointState state() const;
 
@@ -848,12 +866,14 @@ public:
         QRectF screenRect() const;
 
         qreal pressure() const;
+        qreal rotation() const;
         QVector2D velocity() const;
         InfoFlags flags() const;
         QVector<QPointF> rawScreenPositions() const;
 
         // internal
         void setId(int id);
+        void setUniqueId(qint64 uid);
         void setState(Qt::TouchPointStates state);
         void setPos(const QPointF &pos);
         void setScenePos(const QPointF &scenePos);
@@ -871,6 +891,7 @@ public:
         void setSceneRect(const QRectF &sceneRect);
         void setScreenRect(const QRectF &screenRect);
         void setPressure(qreal pressure);
+        void setRotation(qreal angle);
         void setVelocity(const QVector2D &v);
         void setFlags(InfoFlags flags);
         void setRawScreenPositions(const QVector<QPointF> &positions);