iOS: Add support for hover feature for Apple Pencil 2nd gen or later

Add UIHoverGestureRecognizer to support Hover feature.

Task-number: QTBUG-128473
Change-Id: I73bbd1b8cca1ffcb8fcc27f6c26cb4ab8830c690
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

src/plugins/platforms/ios/quiview.mm

@@ -59,6 +59,9 @@ inline ulong getTimeStamp(UIEvent *event)
     UIPanGestureRecognizer *m_scrollGestureRecognizer;
     CGPoint m_lastScrollCursorPos;
     CGPoint m_lastScrollDelta;
+#if QT_CONFIG(tabletevent)
+    UIHoverGestureRecognizer *m_hoverGestureRecognizer;
+#endif
 }
 
 + (Class)layerClass
@@ -99,6 +102,13 @@ inline ulong getTimeStamp(UIEvent *event)
         m_lastScrollCursorPos = CGPointZero;
         [self addGestureRecognizer:m_scrollGestureRecognizer];
 
+#if QT_CONFIG(tabletevent)
+        m_hoverGestureRecognizer = [[UIHoverGestureRecognizer alloc]
+                                     initWithTarget:self
+                                     action:@selector(handleHover:)];
+        [self addGestureRecognizer:m_hoverGestureRecognizer];
+#endif
+
         // Set up layer
         if ([self.layer isKindOfClass:CAMetalLayer.class]) {
             QWindow *window = self.platformWindow->window();
@@ -362,6 +372,39 @@ inline ulong getTimeStamp(UIEvent *event)
     return [super pointInside:point withEvent:event];
 }
 
+#if QT_CONFIG(tabletevent)
+- (void)handlePencilEventForLocationInView:(CGPoint)locationInView withState:(QEventPoint::State)state withTimestamp:(ulong)timeStamp
+    withForce:(CGFloat)force withMaximumPossibleForce:(CGFloat)maximumPossibleForce withZOffset:(CGFloat)zOffset
+    withAzimuthUnitVector:(CGVector)azimuth withAltitudeAngleRadian:(CGFloat)altitudeAngleRadian
+{
+    QIOSIntegration *iosIntegration = QIOSIntegration::instance();
+
+    QPointF localViewPosition = QPointF::fromCGPoint(locationInView);
+    QPoint localViewPositionI = localViewPosition.toPoint();
+    QPointF globalScreenPosition = self.platformWindow->mapToGlobal(localViewPositionI) +
+            (localViewPosition - localViewPositionI);
+    qreal pressure = 0;
+    if (force != 0 && maximumPossibleForce != 0)
+        pressure = force / maximumPossibleForce;
+    // azimuth unit vector: +x to the right, +y going downwards
+    // altitudeAngleRadian given in radians, pi / 2 is with the stylus perpendicular to the iPad, smaller values mean more tilted, but never negative.
+    // Convert to degrees with zero being perpendicular.
+    qreal altitudeAngle = 90 - qRadiansToDegrees(altitudeAngleRadian);
+    qreal xTilt = qBound(-60.0, altitudeAngle * azimuth.dx, 60.0);
+    qreal yTilt = qBound(-60.0, altitudeAngle * azimuth.dy, 60.0);
+
+    qCDebug(lcQpaTablet) << ":" << timeStamp << localViewPosition << pressure << state << "azimuth" << azimuth.dx << azimuth.dy
+                << "altitude" << altitudeAngleRadian << "xTilt" << xTilt << "yTilt" << yTilt;
+    QWindowSystemInterface::handleTabletEvent(self.platformWindow->window(), timeStamp,
+            // device, local, global
+            iosIntegration->pencilDevice(), localViewPosition, globalScreenPosition,
+            // buttons
+            state == QEventPoint::State::Released ? Qt::NoButton : Qt::LeftButton,
+            // pressure, xTilt, yTilt, tangentialPressure, rotation, z, modifiers
+            pressure, xTilt, yTilt, 0, 0, zOffset, Qt::NoModifier);
+}
+#endif
+
 - (void)handleTouches:(NSSet *)touches withEvent:(UIEvent *)event withState:(QEventPoint::State)state withTimestamp:(ulong)timeStamp
 {
     QIOSIntegration *iosIntegration = QIOSIntegration::instance();
@@ -370,30 +413,11 @@ inline ulong getTimeStamp(UIEvent *event)
 #if QT_CONFIG(tabletevent)
     if (m_activePencilTouch && [touches containsObject:m_activePencilTouch]) {
         NSArray<UITouch *> *cTouches = [event coalescedTouchesForTouch:m_activePencilTouch];
-        int i = 0;
         for (UITouch *cTouch in cTouches) {
-            QPointF localViewPosition = QPointF::fromCGPoint([cTouch preciseLocationInView:self]);
+            [self handlePencilEventForLocationInView:[cTouch preciseLocationInView:self] withState:state withTimestamp:timeStamp
-            QPoint localViewPositionI = localViewPosition.toPoint();
+                withForce:cTouch.force withMaximumPossibleForce:cTouch.maximumPossibleForce withZOffset:0
-            QPointF globalScreenPosition = self.platformWindow->mapToGlobal(localViewPositionI) +
+                withAzimuthUnitVector:[cTouch azimuthUnitVectorInView:self]
-                    (localViewPosition - localViewPositionI);
+                withAltitudeAngleRadian:cTouch.altitudeAngle];
-            qreal pressure = cTouch.force / cTouch.maximumPossibleForce;
-            // azimuth unit vector: +x to the right, +y going downwards
-            CGVector azimuth = [cTouch azimuthUnitVectorInView:self];
-            // altitudeAngle given in radians, pi / 2 is with the stylus perpendicular to the iPad, smaller values mean more tilted, but never negative.
-            // Convert to degrees with zero being perpendicular.
-            qreal altitudeAngle = 90 - qRadiansToDegrees(cTouch.altitudeAngle);
-            qreal xTilt = qBound(-60.0, altitudeAngle * azimuth.dx, 60.0);
-            qreal yTilt = qBound(-60.0, altitudeAngle * azimuth.dy, 60.0);
-            qCDebug(lcQpaTablet) << i << ":" << timeStamp << localViewPosition << pressure << state << "azimuth" << azimuth.dx << azimuth.dy
-                    << "altitude" << cTouch.altitudeAngle << "xTilt" << xTilt << "yTilt" << yTilt;
-            QWindowSystemInterface::handleTabletEvent(self.platformWindow->window(), timeStamp,
-                    // device, local, global
-                    iosIntegration->pencilDevice(), localViewPosition, globalScreenPosition,
-                    // buttons
-                    state == QEventPoint::State::Released ? Qt::NoButton : Qt::LeftButton,
-                    // pressure, xTilt, yTilt, tangentialPressure, rotation, z, modifiers
-                    pressure, xTilt, yTilt, 0, 0, 0, Qt::NoModifier);
-            ++i;
         }
     }
 #endif
@@ -759,6 +783,28 @@ inline ulong getTimeStamp(UIEvent *event)
 }
 #endif // QT_CONFIG(wheelevent)
 
+#if QT_CONFIG(tabletevent)
+- (void)handleHover:(UIHoverGestureRecognizer *)recognizer
+{
+    ulong timeStamp = [[NSProcessInfo processInfo] systemUptime] * 1000;
+
+    CGFloat zOffset = 0;
+    if (@available(ios 16.1, *))
+        zOffset = [recognizer zOffset];
+
+    CGVector azimuth;
+    CGFloat altitudeAngleRadian = 0;
+    if (@available(ios 16.4, *)) {
+        azimuth = [recognizer azimuthUnitVectorInView:self];
+        altitudeAngleRadian = recognizer.altitudeAngle;
+    }
+
+    [self handlePencilEventForLocationInView:[recognizer locationInView:self] withState:QEventPoint::State::Released
+        withTimestamp:timeStamp withForce:0 withMaximumPossibleForce:0 withZOffset:zOffset
+        withAzimuthUnitVector:azimuth withAltitudeAngleRadian:altitudeAngleRadian];
+}
+#endif
+
 @end
 
 @implementation UIView (QtHelpers)