Implemented pinch gesture recognizer.

Reviewed-by: trustme

9 files changed, 130 insertions, 102 deletions

diff --git a/examples/gestures/imagegestures/imagewidget.cpp b/examples/gestures/imagegestures/imagewidget.cpp
index 28de6da270..c798fcc479 100644
--- a/examples/gestures/imagegestures/imagewidget.cpp
+++ b/examples/gestures/imagegestures/imagewidget.cpp
@@ -102,17 +102,13 @@ void ImageWidget::mouseDoubleClickEvent(QMouseEvent *)
 //! [gesture event handler]
 bool ImageWidget::gestureEvent(QGestureEvent *event)
 {
-    if (QGesture *pan = event->gesture(Qt::PanGesture)) {
-        panTriggered(static_cast<QPanGesture*>(pan));
-        return true;
-    } else if (QGesture *pinch = event->gesture(Qt::PinchGesture)) {
-        pinchTriggered(static_cast<QPinchGesture*>(pinch));
-        return true;
-    } else if (QGesture *swipe = event->gesture(Qt::SwipeGesture)) {
-        swipeTriggered(static_cast<QSwipeGesture*>(swipe));
-        return true;
-    }
-    return false;
+    if (QGesture *pan = event->gesture(Qt::PanGesture))
+        panTriggered(static_cast<QPanGesture *>(pan));
+    if (QGesture *pinch = event->gesture(Qt::PinchGesture))
+        pinchTriggered(static_cast<QPinchGesture *>(pinch));
+    if (QGesture *swipe = event->gesture(Qt::SwipeGesture))
+        swipeTriggered(static_cast<QSwipeGesture *>(swipe));
+    return true;
 }
 //! [gesture event handler]
 
diff --git a/src/gui/kernel/qgesture_p.h b/src/gui/kernel/qgesture_p.h
index 34fbb26c87..73a6bcf0f4 100644
--- a/src/gui/kernel/qgesture_p.h
+++ b/src/gui/kernel/qgesture_p.h
@@ -121,6 +121,9 @@ public:
     qreal totalRotationAngle;
     qreal lastRotationAngle;
     qreal rotationAngle;
+
+    bool isNewSequence;
+    QPointF startPosition[2];
 };
 
 class QSwipeGesturePrivate : public QGesturePrivate
diff --git a/src/gui/kernel/qgesturemanager.cpp b/src/gui/kernel/qgesturemanager.cpp
index 1d33c84873..6ea350ba15 100644
--- a/src/gui/kernel/qgesturemanager.cpp
+++ b/src/gui/kernel/qgesturemanager.cpp
@@ -77,6 +77,7 @@ QGestureManager::QGestureManager(QObject *parent)
   #endif
 #else
     registerGestureRecognizer(new QPanGestureRecognizer);
+    registerGestureRecognizer(new QPinchGestureRecognizer);
 #endif
 }
 
diff --git a/src/gui/kernel/qstandardgestures.cpp b/src/gui/kernel/qstandardgestures.cpp
index dec2311da2..57cf12d966 100644
--- a/src/gui/kernel/qstandardgestures.cpp
+++ b/src/gui/kernel/qstandardgestures.cpp
@@ -44,6 +44,7 @@
 #include "qgesture_p.h"
 #include "qevent.h"
 #include "qwidget.h"
+#include "qabstractscrollarea.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -54,7 +55,13 @@ QPanGestureRecognizer::QPanGestureRecognizer()
 QGesture *QPanGestureRecognizer::createGesture(QObject *target)
 {
     if (target && target->isWidgetType()) {
+#if defined(Q_OS_WIN)
+        // for scroll areas on Windows we want to use native gestures instead
+        if (!qobject_cast<QAbstractScrollArea *>(target->parent()))
+            static_cast<QWidget *>(target)->setAttribute(Qt::WA_AcceptTouchEvents);
+#else
         static_cast<QWidget *>(target)->setAttribute(Qt::WA_AcceptTouchEvents);
+#endif
     }
     return new QPanGesture;
 }
@@ -132,104 +139,124 @@ void QPanGestureRecognizer::reset(QGesture *state)
     d->lastPosition = QPoint();
     d->acceleration = 0;
 
-//#if defined(QT_MAC_USE_COCOA)
-//    d->singleTouchPanTimer.stop();
-//    d->prevMousePos = QPointF(0, 0);
-//#endif
-
     QGestureRecognizer::reset(state);
 }
 
-/*
-bool QPanGestureRecognizer::event(QEvent *event)
+
+//
+// QPinchGestureRecognizer
+//
+
+QPinchGestureRecognizer::QPinchGestureRecognizer()
 {
-#if defined(QT_MAC_USE_COCOA)
-    Q_D(QPanGesture);
-    if (event->type() == QEvent::Timer) {
-        const QTimerEvent *te = static_cast<QTimerEvent *>(event);
-        if (te->timerId() == d->singleTouchPanTimer.timerId()) {
-            d->singleTouchPanTimer.stop();
-            updateState(Qt::GestureStarted);
-        }
+}
+
+QGesture *QPinchGestureRecognizer::createGesture(QObject *target)
+{
+    if (target && target->isWidgetType()) {
+        static_cast<QWidget *>(target)->setAttribute(Qt::WA_AcceptTouchEvents);
     }
-#endif
+    return new QPinchGesture;
+}
 
-    bool consume = false;
+QGestureRecognizer::Result QPinchGestureRecognizer::filterEvent(QGesture *state, QObject *, QEvent *event)
+{
+    QPinchGesture *q = static_cast<QPinchGesture *>(state);
+    QPinchGesturePrivate *d = q->d_func();
 
-#if defined(Q_WS_WIN)
-#elif defined(QT_MAC_USE_COCOA)
-    // The following implements single touch
-    // panning on Mac:
-    const int panBeginDelay = 300;
-    const int panBeginRadius = 3;
-    const QTouchEvent *ev = static_cast<const QTouchEvent*>(event);
+    const QTouchEvent *ev = static_cast<const QTouchEvent *>(event);
+
+    QGestureRecognizer::Result result;
 
     switch (event->type()) {
     case QEvent::TouchBegin: {
-        if (ev->touchPoints().size() == 1) {
-            d->delayManager->setEnabled(true);
-            consume = d->delayManager->append(d->gestureTarget, *event);
-            d->lastPosition = QCursor::pos();
-            d->singleTouchPanTimer.start(panBeginDelay, this);
-        }
-        break;}
+        result = QGestureRecognizer::MaybeGesture;
+        break;
+    }
     case QEvent::TouchEnd: {
-        d->delayManager->setEnabled(false);
-        if (state() != Qt::NoGesture) {
-            updateState(Qt::GestureFinished);
-            consume = true;
-            d->delayManager->clear();
+        if (q->state() != Qt::NoGesture) {
+            result = QGestureRecognizer::GestureFinished;
         } else {
-            d->delayManager->replay();
+            result = QGestureRecognizer::NotGesture;
         }
-        reset();
-        break;}
+        break;
+    }
     case QEvent::TouchUpdate: {
-        consume = d->delayManager->append(d->gestureTarget, *event);
-        if (ev->touchPoints().size() == 1) {
-            if (state() == Qt::NoGesture) {
-                // INVARIANT: The singleTouchTimer has still not fired.
-                // Lets check if the user moved his finger so much from
-                // the starting point that it makes sense to cancel:
-                const QPointF startPos = ev->touchPoints().at(0).startPos().toPoint();
-                const QPointF p = ev->touchPoints().at(0).pos().toPoint();
-                if ((startPos - p).manhattanLength() > panBeginRadius) {
-                    d->delayManager->replay();
-                    consume = false;
-                    reset();
-                } else {
-                    d->lastPosition = QCursor::pos();
-                }
+        d->whatChanged = 0;
+        if (ev->touchPoints().size() == 2) {
+            QTouchEvent::TouchPoint p1 = ev->touchPoints().at(0);
+            QTouchEvent::TouchPoint p2 = ev->touchPoints().at(1);
+
+            d->hotSpot = p1.screenPos();
+            d->isHotSpotSet = true;
+
+            if (d->isNewSequence) {
+                d->startPosition[0] = p1.screenPos();
+                d->startPosition[1] = p2.screenPos();
+            }
+            QLineF line(p1.screenPos(), p2.screenPos());
+            QLineF tmp(line);
+            tmp.setLength(line.length() / 2.);
+            QPointF centerPoint = tmp.p2();
+
+            d->lastCenterPoint = d->centerPoint;
+            d->centerPoint = centerPoint;
+            d->whatChanged |= QPinchGesture::CenterPointChanged;
+
+            const qreal scaleFactor = QLineF(p1.pos(), p2.pos()).length()
+                                      / QLineF(d->startPosition[0],  d->startPosition[1]).length();
+            if (d->isNewSequence) {
+                d->lastScaleFactor = scaleFactor;
             } else {
-                d->delayManager->clear();
-                QPointF mousePos = QCursor::pos();
-                QPointF dist = mousePos - d->lastPosition;
-                d->lastPosition = mousePos;
-                d->lastOffset = d->offset;
-                d->offset = QSizeF(dist.x(), dist.y());
-                d->totalOffset += d->offset;
-                updateState(Qt::GestureUpdated);
+                d->lastScaleFactor = d->scaleFactor;
             }
-        } else if (state() == Qt::NoGesture) {
-            d->delayManager->replay();
-            consume = false;
-            reset();
+            d->scaleFactor = scaleFactor;
+            d->totalScaleFactor += d->scaleFactor - d->lastScaleFactor;
+            d->whatChanged |= QPinchGesture::ScaleFactorChanged;
+
+            const qreal rotationAngle = -line.angle();
+            if (d->isNewSequence)
+                d->lastRotationAngle = rotationAngle;
+            else
+                d->lastRotationAngle = d->rotationAngle;
+            d->rotationAngle = rotationAngle;
+            d->totalRotationAngle += d->rotationAngle - d->lastRotationAngle;
+            d->whatChanged |= QPinchGesture::RotationAngleChanged;
+
+            d->isNewSequence = false;
+            result = QGestureRecognizer::GestureTriggered;
+        } else {
+            d->isNewSequence = true;
+            result = QGestureRecognizer::MaybeGesture;
         }
-        break;}
+        break;
+    }
     case QEvent::MouseButtonPress:
     case QEvent::MouseMove:
     case QEvent::MouseButtonRelease:
-        if (d->delayManager->isEnabled())
-            consume = d->delayManager->append(d->gestureTarget, *event);
+        result = QGestureRecognizer::Ignore;
         break;
     default:
-        return false;
+        result = QGestureRecognizer::Ignore;
+        break;
     }
-#else
-    Q_UNUSED(event);
-#endif
-    return QGestureRecognizer::Ignore;
+    return result;
+}
+
+void QPinchGestureRecognizer::reset(QGesture *state)
+{
+    QPinchGesture *pinch = static_cast<QPinchGesture*>(state);
+    QPinchGesturePrivate *d = pinch->d_func();
+
+    d->whatChanged = 0;
+
+    d->startCenterPoint = d->lastCenterPoint = d->centerPoint = QPointF();
+    d->totalScaleFactor = d->lastScaleFactor = d->scaleFactor = 0;
+    d->totalRotationAngle = d->lastRotationAngle = d->rotationAngle = 0;
+
+    d->isNewSequence = true;
+
+    QGestureRecognizer::reset(state);
 }
-    */
 
 QT_END_NAMESPACE
diff --git a/src/gui/kernel/qstandardgestures_p.h b/src/gui/kernel/qstandardgestures_p.h
index fec5c2fbd9..827b2a2615 100644
--- a/src/gui/kernel/qstandardgestures_p.h
+++ b/src/gui/kernel/qstandardgestures_p.h
@@ -69,6 +69,17 @@ public:
     void reset(QGesture *state);
 };
 
+class QPinchGestureRecognizer : public QGestureRecognizer
+{
+public:
+    QPinchGestureRecognizer();
+
+    QGesture *createGesture(QObject *target);
+
+    QGestureRecognizer::Result filterEvent(QGesture *state, QObject *watched, QEvent *event);
+    void reset(QGesture *state);
+};
+
 QT_END_NAMESPACE
 
 #endif // QSTANDARDGESTURES_P_H
diff --git a/src/gui/kernel/qwidget.cpp b/src/gui/kernel/qwidget.cpp
index ac2808c535..00d9a990a2 100644
--- a/src/gui/kernel/qwidget.cpp
+++ b/src/gui/kernel/qwidget.cpp
@@ -197,6 +197,7 @@ QWidgetPrivate::QWidgetPrivate(int version)
       , picture(0)
 #elif defined(Q_WS_WIN)
       , noPaintOnScreen(0)
+      , nativeGesturePanEnabled(0)
 #elif defined(Q_WS_MAC)
       , needWindowChange(0)
       , isGLWidget(0)
diff --git a/src/gui/kernel/qwidget_win.cpp b/src/gui/kernel/qwidget_win.cpp
index 5bf7649198..3a92735e09 100644
--- a/src/gui/kernel/qwidget_win.cpp
+++ b/src/gui/kernel/qwidget_win.cpp
@@ -2071,17 +2071,6 @@ void QWidgetPrivate::winSetupGestures()
             gc[0].dwBlock = GC_PAN;
         }
 
-//        gc[1].dwID = GID_ZOOM;
-//        if (gestures.pinch)
-//            gc[1].dwWant = GC_ZOOM;
-//        else
-//            gc[1].dwBlock = GC_ZOOM;
-//        gc[2].dwID = GID_ROTATE;
-//        if (gestures.pinch)
-//            gc[2].dwWant = GC_ROTATE;
-//        else
-//            gc[2].dwBlock = GC_ROTATE;
-
         qAppPriv->SetGestureConfig(winid, 0, sizeof(gc)/sizeof(gc[0]), gc, sizeof(gc[0]));
     }
 }
diff --git a/src/gui/kernel/qwinnativepangesturerecognizer_win.cpp b/src/gui/kernel/qwinnativepangesturerecognizer_win.cpp
index 12d3058188..c3c8a28cf6 100644
--- a/src/gui/kernel/qwinnativepangesturerecognizer_win.cpp
+++ b/src/gui/kernel/qwinnativepangesturerecognizer_win.cpp
@@ -56,16 +56,16 @@ QWinNativePanGestureRecognizer::QWinNativePanGestureRecognizer()
 {
 }
 
-QGesture* QWinNativePanGestureRecognizer::createGesture(QObject *target) const
+QGesture *QWinNativePanGestureRecognizer::createGesture(QObject *target)
 {
     if (!target)
         return new QPanGesture; // a special case
-    if (qobject_cast<QGraphicsObject*>(target))
-        return 0;
     if (!target->isWidgetType())
         return 0;
+    if (qobject_cast<QGraphicsObject *>(target))
+        return 0;
 
-    QWidget *q = static_cast<QWidget*>(target);
+    QWidget *q = static_cast<QWidget *>(target);
     QWidgetPrivate *d = q->d_func();
     d->nativeGesturePanEnabled = true;
     d->winSetupGestures();
diff --git a/src/gui/kernel/qwinnativepangesturerecognizer_win_p.h b/src/gui/kernel/qwinnativepangesturerecognizer_win_p.h
index a1e8511f66..1d723daa3e 100644
--- a/src/gui/kernel/qwinnativepangesturerecognizer_win_p.h
+++ b/src/gui/kernel/qwinnativepangesturerecognizer_win_p.h
@@ -62,7 +62,7 @@ class QWinNativePanGestureRecognizer : public QGestureRecognizer
 public:
     QWinNativePanGestureRecognizer();
 
-    QGesture* createGesture(QObject *target) const;
+    QGesture *createGesture(QObject *target);
 
     QGestureRecognizer::Result filterEvent(QGesture *state, QObject *watched, QEvent *event);
     void reset(QGesture *state);