Use use touch events to generate mouse events in Quick canvas.

Allowing the canvas to deal with mouse event emulation provides
a couple of advantages: 1. touches outside a reactive area can
be ignored, allowing a touch within a reactive area to become
the "mouse touch". 2. we can extend the mouse events with
data available in touch events for use within the quick elements;
specifically velocity in this case.

Change-Id: Id9df397f1a3a03dbda2ef5dcf6189e7eb3377356
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>

4 files changed, 184 insertions, 19 deletions

diff --git a/src/quick/items/qquickcanvas.cpp b/src/quick/items/qquickcanvas.cpp
index ad2f016b28..c9371b5087 100644
--- a/src/quick/items/qquickcanvas.cpp
+++ b/src/quick/items/qquickcanvas.cpp
@@ -44,6 +44,7 @@
 
 #include "qquickitem.h"
 #include "qquickitem_p.h"
+#include "qquickevents_p_p.h"
 
 #include <QtQuick/private/qsgrenderer_p.h>
 #include <QtQuick/private/qsgtexture_p.h>
@@ -60,6 +61,7 @@
 #include <QtGui/qpainter.h>
 #include <QtGui/qevent.h>
 #include <QtGui/qmatrix4x4.h>
+#include <QtGui/qstylehints.h>
 #include <QtCore/qvarlengtharray.h>
 #include <QtCore/qabstractanimation.h>
 #include <QtDeclarative/qdeclarativeincubator.h>
@@ -68,6 +70,7 @@
 
 QT_BEGIN_NAMESPACE
 
+DEFINE_BOOL_CONFIG_OPTION(qmlTranslateTouchToMouse, QML_TRANSLATE_TOUCH_TO_MOUSE)
 
 void QQuickCanvasPrivate::updateFocusItemTransform()
 {
@@ -283,6 +286,8 @@ QQuickCanvasPrivate::QQuickCanvasPrivate()
     : rootItem(0)
     , activeFocusItem(0)
     , mouseGrabberItem(0)
+    , touchMouseId(-1)
+    , touchMousePressTimestamp(0)
     , renderWithoutShowing(false)
     , dirtyItemList(0)
     , context(0)
@@ -348,6 +353,76 @@ void QQuickCanvasPrivate::initRootItem()
     rootItem->setHeight(q->height());
 }
 
+static QQuickMouseEventEx touchToMouseEvent(QEvent::Type type, const QTouchEvent::TouchPoint &p)
+{
+    QQuickMouseEventEx me(type, p.pos(), p.scenePos(), p.screenPos(),
+            Qt::LeftButton, Qt::LeftButton, 0);
+    me.setVelocity(p.velocity());
+    return me;
+}
+
+void QQuickCanvasPrivate::translateTouchToMouse(QTouchEvent *event)
+{
+    for (int i = 0; i < event->touchPoints().count(); ++i) {
+        QTouchEvent::TouchPoint p = event->touchPoints().at(i);
+        if (touchMouseId == -1 && p.state() & Qt::TouchPointPressed) {
+            bool doubleClick = event->timestamp() - touchMousePressTimestamp
+                            < static_cast<ulong>(qApp->styleHints()->mouseDoubleClickInterval());
+            touchMousePressTimestamp = event->timestamp();
+            if (doubleClick) {
+                QQuickMouseEventEx me = touchToMouseEvent(QEvent::MouseButtonDblClick, p);
+                me.setTimestamp(event->timestamp());
+                me.setAccepted(false);
+                deliverMouseEvent(&me);
+                if (me.isAccepted()) {
+                    touchMouseId = p.id();
+                    event->setAccepted(true);
+                }
+            }
+            QQuickMouseEventEx me = touchToMouseEvent(QEvent::MouseButtonPress, p);
+            me.setTimestamp(event->timestamp());
+            me.setAccepted(false);
+            deliverMouseEvent(&me);
+            if (me.isAccepted()) {
+                touchMouseId = p.id();
+                event->setAccepted(true);
+                break;
+            }
+        } else if (p.id() == touchMouseId) {
+            if (p.state() & Qt::TouchPointMoved) {
+                QQuickMouseEventEx me = touchToMouseEvent(QEvent::MouseMove, p);
+                me.setTimestamp(event->timestamp());
+                if (!mouseGrabberItem) {
+                    if (lastMousePosition.isNull())
+                        lastMousePosition = me.windowPos();
+                    QPointF last = lastMousePosition;
+                    lastMousePosition = me.windowPos();
+
+                    bool accepted = me.isAccepted();
+                    bool delivered = deliverHoverEvent(rootItem, me.windowPos(), last, me.modifiers(), accepted);
+                    if (!delivered) {
+                        //take care of any exits
+                        accepted = clearHover();
+                    }
+                    me.setAccepted(accepted);
+                    break;
+                }
+
+                deliverMouseEvent(&me);
+            } else if (p.state() & Qt::TouchPointReleased) {
+                touchMouseId = -1;
+                if (!mouseGrabberItem)
+                    return;
+                QQuickMouseEventEx me = touchToMouseEvent(QEvent::MouseButtonRelease, p);
+                me.setTimestamp(event->timestamp());
+                deliverMouseEvent(&me);
+                mouseGrabberItem = 0;
+            }
+            break;
+        }
+    }
+}
+
 void QQuickCanvasPrivate::transformTouchPoints(QList<QTouchEvent::TouchPoint> &touchPoints, const QTransform &transform)
 {
     for (int i=0; i<touchPoints.count(); i++) {
@@ -752,6 +827,8 @@ bool QQuickCanvas::event(QEvent *e)
         QTouchEvent *touch = static_cast<QTouchEvent *>(e);
         d->translateTouchEvent(touch);
         d->deliverTouchEvent(touch);
+        if (qmlTranslateTouchToMouse())
+            d->translateTouchToMouse(touch);
 
         return touch->isAccepted();
     }
@@ -852,8 +929,11 @@ bool QQuickCanvasPrivate::deliverMouseEvent(QMouseEvent *event)
     if (mouseGrabberItem) {
         QQuickItemPrivate *mgPrivate = QQuickItemPrivate::get(mouseGrabberItem);
         const QTransform &transform = mgPrivate->canvasToItemTransform();
-        QMouseEvent me(event->type(), transform.map(event->windowPos()), event->windowPos(), event->screenPos(),
-                       event->button(), event->buttons(), event->modifiers());
+        QQuickMouseEventEx me(event->type(), transform.map(event->windowPos()),
+                                event->windowPos(), event->screenPos(),
+                                event->button(), event->buttons(), event->modifiers());
+        if (QQuickMouseEventEx::extended(event))
+            me.setVelocity(QQuickMouseEventEx::extended(event)->velocity());
         me.accept();
         q->sendEvent(mouseGrabberItem, &me);
         event->setAccepted(me.isAccepted());
@@ -867,7 +947,8 @@ bool QQuickCanvasPrivate::deliverMouseEvent(QMouseEvent *event)
 void QQuickCanvas::mousePressEvent(QMouseEvent *event)
 {
     Q_D(QQuickCanvas);
-
+    if (qmlTranslateTouchToMouse())
+        return; // We are using touch events
 #ifdef MOUSE_DEBUG
     qWarning() << "QQuickCanvas::mousePressEvent()" << event->pos() << event->button() << event->buttons();
 #endif
@@ -878,7 +959,8 @@ void QQuickCanvas::mousePressEvent(QMouseEvent *event)
 void QQuickCanvas::mouseReleaseEvent(QMouseEvent *event)
 {
     Q_D(QQuickCanvas);
-
+    if (qmlTranslateTouchToMouse())
+        return; // We are using touch events
 #ifdef MOUSE_DEBUG
     qWarning() << "QQuickCanvas::mouseReleaseEvent()" << event->pos() << event->button() << event->buttons();
 #endif
@@ -895,6 +977,8 @@ void QQuickCanvas::mouseReleaseEvent(QMouseEvent *event)
 void QQuickCanvas::mouseDoubleClickEvent(QMouseEvent *event)
 {
     Q_D(QQuickCanvas);
+    if (qmlTranslateTouchToMouse())
+        return; // We are using touch events
 
 #ifdef MOUSE_DEBUG
     qWarning() << "QQuickCanvas::mouseDoubleClickEvent()" << event->pos() << event->button() << event->buttons();
@@ -930,7 +1014,8 @@ bool QQuickCanvasPrivate::sendHoverEvent(QEvent::Type type, QQuickItem *item,
 void QQuickCanvas::mouseMoveEvent(QMouseEvent *event)
 {
     Q_D(QQuickCanvas);
-
+    if (qmlTranslateTouchToMouse())
+        return; // We are using touch events
 #ifdef MOUSE_DEBUG
     qWarning() << "QQuickCanvas::mouseMoveEvent()" << event->pos() << event->button() << event->buttons();
 #endif
diff --git a/src/quick/items/qquickcanvas_p.h b/src/quick/items/qquickcanvas_p.h
index e6b9f7d8a0..d4d6a01f75 100644
--- a/src/quick/items/qquickcanvas_p.h
+++ b/src/quick/items/qquickcanvas_p.h
@@ -113,9 +113,12 @@ public:
     QQuickItem *activeFocusItem;
     QQuickItem *mouseGrabberItem;
     QQuickDragGrabber dragGrabber;
+    int touchMouseId;
+    ulong touchMousePressTimestamp;
 
     // Mouse positions are saved in widget coordinates
     QPointF lastMousePosition;
+    void translateTouchToMouse(QTouchEvent *event);
     void translateTouchEvent(QTouchEvent *touchEvent);
     static void transformTouchPoints(QList<QTouchEvent::TouchPoint> &touchPoints, const QTransform &transform);
     bool deliverInitialMousePressEvent(QQuickItem *, QMouseEvent *);
diff --git a/src/quick/items/qquickevents_p_p.h b/src/quick/items/qquickevents_p_p.h
index 91b218875c..3298fcef9c 100644
--- a/src/quick/items/qquickevents_p_p.h
+++ b/src/quick/items/qquickevents_p_p.h
@@ -58,6 +58,7 @@
 #include <qdeclarative.h>
 
 #include <QtCore/qobject.h>
+#include <QtGui/qvector2d.h>
 #include <QtGui/qevent.h>
 
 QT_BEGIN_NAMESPACE
@@ -137,6 +138,60 @@ private:
     bool _accepted;
 };
 
+class QQuickMouseEventEx : public QMouseEvent
+{
+public:
+    QQuickMouseEventEx(Type type, const QPointF &pos, Qt::MouseButton button,
+                Qt::MouseButtons buttons, Qt::KeyboardModifiers modifiers)
+        : QMouseEvent(type,pos,button,buttons,modifiers)
+    {
+    }
+
+    QQuickMouseEventEx(Type type, const QPointF &pos, const QPointF &globalPos,
+                Qt::MouseButton button, Qt::MouseButtons buttons,
+                Qt::KeyboardModifiers modifiers)
+        : QMouseEvent(type,pos,globalPos,button,buttons,modifiers)
+    {
+    }
+
+    QQuickMouseEventEx(Type type, const QPointF &pos, const QPointF &windowPos, const QPointF &globalPos,
+                Qt::MouseButton button, Qt::MouseButtons buttons,
+                Qt::KeyboardModifiers modifiers)
+        : QMouseEvent(type,pos,windowPos,globalPos,button,buttons,modifiers)
+    {
+    }
+
+    QQuickMouseEventEx(const QMouseEvent &event)
+        : QMouseEvent(event)
+    {
+        if (extended(&event))
+            setVelocity(extended(&event)->velocity());
+    }
+
+    static const QQuickMouseEventEx *extended(const QMouseEvent *e) {
+        const QQuickMouseEventEx *ex = static_cast<const QQuickMouseEventEx*>(e);
+        return reinterpret_cast<const QMouseEvent*>(ex->d) == e ? ex : 0;
+    }
+    static QQuickMouseEventEx *extended(QMouseEvent *e) {
+        QQuickMouseEventEx *ex = static_cast<QQuickMouseEventEx*>(e);
+        return reinterpret_cast<QMouseEvent*>(ex->d) == e ? ex : 0;
+    }
+
+    void setExtended() {
+        d = reinterpret_cast<QEventPrivate*>(this);
+    }
+
+    void setVelocity(const QVector2D &v) {
+        setExtended();
+        _velocity = v;
+    }
+    QVector2D velocity() const { return _velocity; }
+
+private:
+    QVector2D _velocity;
+};
+
+
 QT_END_NAMESPACE
 
 QML_DECLARE_TYPE(QQuickKeyEvent)
diff --git a/src/quick/items/qquickflickable.cpp b/src/quick/items/qquickflickable.cpp
index 7d497fbbf0..43aaf92b1a 100644
--- a/src/quick/items/qquickflickable.cpp
+++ b/src/quick/items/qquickflickable.cpp
@@ -43,6 +43,7 @@
 #include "qquickflickable_p_p.h"
 #include "qquickcanvas.h"
 #include "qquickcanvas_p.h"
+#include "qquickevents_p_p.h"
 
 #include <QtDeclarative/qdeclarativeinfo.h>
 #include <QtGui/qevent.h>
@@ -907,7 +908,7 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
                 }
             }
             if (!rejectY && stealMouse && dy != 0.0) {
-                vData.move.setValue(qRound(newY));
+                vData.move.setValue(newY);
                 vMoved = true;
             }
             if (qAbs(dy) > qApp->styleHints()->startDragDistance())
@@ -939,7 +940,7 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
                 }
             }
             if (!rejectX && stealMouse && dx != 0.0) {
-                hData.move.setValue(qRound(newX));
+                hData.move.setValue(newX);
                 hMoved = true;
             }
 
@@ -972,12 +973,23 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
         if (elapsed <= 0)
             return;
         lastPosTime = currentTimestamp;
-        qreal dy = event->localPos().y()-lastPos.y();
-        if (q->yflick() && !rejectY)
-            vData.addVelocitySample(dy/elapsed, maxVelocity);
-        qreal dx = event->localPos().x()-lastPos.x();
-        if (q->xflick() && !rejectX)
-            hData.addVelocitySample(dx/elapsed, maxVelocity);
+        QQuickMouseEventEx *extended = QQuickMouseEventEx::extended(event);
+        if (q->yflick() && !rejectY) {
+            if (extended) {
+                vData.addVelocitySample(extended->velocity().y(), maxVelocity);
+            } else {
+                qreal dy = event->localPos().y()-lastPos.y();
+                vData.addVelocitySample(dy/elapsed, maxVelocity);
+            }
+        }
+        if (q->xflick() && !rejectX) {
+            if (extended) {
+                hData.addVelocitySample(extended->velocity().x(), maxVelocity);
+            } else {
+                qreal dx = event->localPos().x()-lastPos.x();
+                hData.addVelocitySample(dx/elapsed, maxVelocity);
+            }
+        }
     }
 
     lastPos = event->localPos();
@@ -1005,7 +1017,11 @@ void QQuickFlickablePrivate::handleMouseReleaseEvent(QMouseEvent *event)
 
     bool canBoost = false;
 
-    qreal vVelocity = elapsed < 100 ? vData.velocity : 0;
+    qreal vVelocity = 0;
+    if (elapsed < 100 && vData.velocity != 0.) {
+        QQuickMouseEventEx *extended = QQuickMouseEventEx::extended(event);
+        vVelocity = extended ? extended->velocity().y() : vData.velocity;
+    }
     if (vData.atBeginning || vData.atEnd) {
         vVelocity /= 2;
     } else if (vData.continuousFlickVelocity != 0.0
@@ -1016,7 +1032,11 @@ void QQuickFlickablePrivate::handleMouseReleaseEvent(QMouseEvent *event)
         canBoost = true;
     }
 
-    qreal hVelocity = elapsed < 100 ? hData.velocity : 0;
+    qreal hVelocity = 0;
+    if (elapsed < 100 && hData.velocity != 0.) {
+        QQuickMouseEventEx *extended = QQuickMouseEventEx::extended(event);
+        hVelocity = extended ? extended->velocity().x() : hData.velocity;
+    }
     if (hData.atBeginning || hData.atEnd) {
         hVelocity /= 2;
     } else if (hData.continuousFlickVelocity != 0.0
@@ -1155,7 +1175,7 @@ void QQuickFlickablePrivate::captureDelayedPress(QMouseEvent *event)
     if (!isOutermostPressDelay())
         return;
     delayedPressTarget = q->canvas()->mouseGrabberItem();
-    delayedPressEvent = new QMouseEvent(*event);
+    delayedPressEvent = new QQuickMouseEventEx(*event);
     delayedPressEvent->setAccepted(false);
     delayedPressTimer.start(pressDelay, q);
 }
@@ -1746,9 +1766,11 @@ bool QQuickFlickable::sendMouseEvent(QMouseEvent *event)
     bool disabledItem = grabber && !grabber->isEnabled();
     bool stealThisEvent = d->stealMouse;
     if ((stealThisEvent || myRect.contains(event->windowPos())) && (!grabber || !grabber->keepMouseGrab() || disabledItem)) {
-        QMouseEvent mouseEvent(event->type(), mapFromScene(event->windowPos()), event->windowPos(), event->screenPos(),
-                               event->button(), event->buttons(), event->modifiers());
-
+        QQuickMouseEventEx mouseEvent(event->type(), mapFromScene(event->windowPos()),
+                                event->windowPos(), event->screenPos(),
+                                event->button(), event->buttons(), event->modifiers());
+        if (QQuickMouseEventEx::extended(event))
+            mouseEvent.setVelocity(QQuickMouseEventEx::extended(event)->velocity());
         mouseEvent.setTimestamp(event->timestamp());
         mouseEvent.setAccepted(false);