Don't try to maintain a current and active list of points for the app and widgets/items

Instead, build the list of touchPoints per event. This solves the problem when encountering
releases early in the active/current list while there are still touch points in move/stationary
states (which effectively caused the code to "forget" about the released point).

5 files changed, 30 insertions, 115 deletions

diff --git a/src/gui/graphicsview/qgraphicsscene.cpp b/src/gui/graphicsview/qgraphicsscene.cpp
index e7a0547..1cd51d6 100644
--- a/src/gui/graphicsview/qgraphicsscene.cpp
+++ b/src/gui/graphicsview/qgraphicsscene.cpp
@@ -5694,13 +5694,12 @@ void QGraphicsScenePrivate::updateTouchPointsForItem(QGraphicsItem *item,
     }
 }
 
-QGraphicsSceneTouchEvent::TouchPoint *QGraphicsScenePrivate::findClosestTouchPoint(const QList<QGraphicsSceneTouchEvent::TouchPoint *> &sceneActiveTouchPoints,
-                                                                       const QPointF &scenePos)
+QGraphicsSceneTouchEvent::TouchPoint *QGraphicsScenePrivate::findClosestTouchPoint(const QPointF &scenePos)
 {
     QGraphicsSceneTouchEvent::TouchPoint *closestTouchPoint = 0;
     qreal closestDistance;
-    for (int i = 0; i < sceneActiveTouchPoints.count(); ++i) {
-        QGraphicsSceneTouchEvent::TouchPoint *touchPoint = sceneActiveTouchPoints.at(i);
+    for (int i = 0; i < sceneCurrentTouchPoints.count(); ++i) {
+        QGraphicsSceneTouchEvent::TouchPoint *touchPoint = sceneCurrentTouchPoints.at(i);
         qreal distance = QLineF(scenePos, touchPoint->scenePos()).length();
         if (!closestTouchPoint || distance < closestDistance) {
             closestTouchPoint = touchPoint;
@@ -5710,8 +5709,7 @@ QGraphicsSceneTouchEvent::TouchPoint *QGraphicsScenePrivate::findClosestTouchPoi
     return closestTouchPoint;
 }
 
-void QGraphicsScenePrivate::appendTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint,
-                                             QList<QGraphicsSceneTouchEvent::TouchPoint *> *currentTouchPoints)
+void QGraphicsScenePrivate::appendTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint)
 {
     // insort touch point (for the app)
     int at = 0;
@@ -5720,16 +5718,9 @@ void QGraphicsScenePrivate::appendTouchPoint(QGraphicsSceneTouchEvent::TouchPoin
             break;
     }
     sceneCurrentTouchPoints.insert(at, touchPoint);
-    // again, for the items's currentTouchPoints
-    for (at = 0; at < currentTouchPoints->count(); ++at) {
-        if (currentTouchPoints->at(at)->id() > touchPoint->id())
-            break;
-    }
-    currentTouchPoints->insert(at, touchPoint);
 }
 
-void QGraphicsScenePrivate::removeTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint,
-                                             QList<QGraphicsSceneTouchEvent::TouchPoint *> *currentTouchPoints)
+void QGraphicsScenePrivate::removeTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint)
 {
     // remove touch point from all known touch points
     for (int i = qMin(sceneCurrentTouchPoints.count() - 1, touchPoint->id()); i >= 0; --i) {
@@ -5738,21 +5729,13 @@ void QGraphicsScenePrivate::removeTouchPoint(QGraphicsSceneTouchEvent::TouchPoin
             break;
         }
     }
-    // again, for the items's currentTouchPoints
-    for (int i = qMin(currentTouchPoints->count() - 1, touchPoint->id()); i >= 0; --i) {
-        if (currentTouchPoints->at(i) == touchPoint) {
-            currentTouchPoints->removeAt(i);
-            break;
-        }
-    }
 }
 
 void QGraphicsScenePrivate::touchEventHandler(QGraphicsSceneTouchEvent *sceneTouchEvent)
 {
-    QList<QGraphicsSceneTouchEvent::TouchPoint *> sceneActiveTouchPoints = sceneCurrentTouchPoints;
-
     typedef QPair<Qt::TouchPointStates, QList<QGraphicsSceneTouchEvent::TouchPoint *> > StatesAndTouchPoints;
     QHash<QGraphicsItem *, StatesAndTouchPoints> itemsNeedingEvents;
+
     for (int i = 0; i < sceneTouchEvent->touchPoints().count(); ++i) {
         QGraphicsSceneTouchEvent::TouchPoint *touchPoint = sceneTouchEvent->touchPoints().at(i);
 
@@ -5765,7 +5748,7 @@ void QGraphicsScenePrivate::touchEventHandler(QGraphicsSceneTouchEvent *sceneTou
                                                     touchPoint->scenePos(),
                                                     sceneTouchEvent->widget());
             item = cachedItemsUnderMouse.isEmpty() ? 0 : cachedItemsUnderMouse.first();
-            QGraphicsSceneTouchEvent::TouchPoint *closestTouchPoint = findClosestTouchPoint(sceneActiveTouchPoints, touchPoint->scenePos());
+            QGraphicsSceneTouchEvent::TouchPoint *closestTouchPoint = findClosestTouchPoint(touchPoint->scenePos());
             if (closestTouchPoint) {
                 QGraphicsItem *closestItem = itemForTouchPointId.value(closestTouchPoint->id());
                 if (!item
@@ -5779,33 +5762,22 @@ void QGraphicsScenePrivate::touchEventHandler(QGraphicsSceneTouchEvent *sceneTou
                 continue;
 
             itemForTouchPointId.insert(touchPoint->id(), item);
-
-            QList<QGraphicsSceneTouchEvent::TouchPoint *> &currentTouchPoints = itemCurrentTouchPoints[item];
-            appendTouchPoint(touchPoint, &currentTouchPoints);
-            // make sure new points are added to activeTouchPoints as well
-            sceneActiveTouchPoints = sceneCurrentTouchPoints;
-            activeTouchPoints = currentTouchPoints;
+            appendTouchPoint(touchPoint);
         } else if (touchPoint->state() == Qt::TouchPointReleased) {
             item = itemForTouchPointId.take(touchPoint->id());
             if (!item)
                 continue;
 
-            QList<QGraphicsSceneTouchEvent::TouchPoint *> &currentTouchPoints = itemCurrentTouchPoints[item];
-            sceneActiveTouchPoints = sceneCurrentTouchPoints;
-            activeTouchPoints = currentTouchPoints;
-            removeTouchPoint(touchPoint, &currentTouchPoints);
+            removeTouchPoint(touchPoint);
         } else {
             item = itemForTouchPointId.value(touchPoint->id());
             if (!item)
                 continue;
-
-            sceneActiveTouchPoints = sceneCurrentTouchPoints;
-            activeTouchPoints = itemCurrentTouchPoints.value(item);
         }
 
         StatesAndTouchPoints &statesAndTouchPoints = itemsNeedingEvents[item];
         statesAndTouchPoints.first |= touchPoint->state();
-        statesAndTouchPoints.second = activeTouchPoints;
+        statesAndTouchPoints.second.append(touchPoint);
     }
 
     if (itemsNeedingEvents.isEmpty()) {
@@ -5856,14 +5828,6 @@ void QGraphicsScenePrivate::touchEventHandler(QGraphicsSceneTouchEvent *sceneTou
             acceptSceneTouchEvent = acceptSceneTouchEvent || res;
             break;
         }
-        case QEvent::GraphicsSceneTouchEnd:
-        {
-            QList<QGraphicsSceneTouchEvent::TouchPoint *> currentTouchPoints = itemCurrentTouchPoints.take(item);
-            if (!currentTouchPoints.isEmpty()) {
-                qFatal("Qt: INTERNAL ERROR, the widget's currentTouchPoints should be empty!");
-            }
-            // fall-through intended
-        }
         default:
             if (item->d_ptr->acceptedTouchBeginEvent) {
                 updateTouchPointsForItem(item, &touchEvent);
@@ -5922,9 +5886,6 @@ bool QGraphicsScenePrivate::sendTouchBeginEvent(QGraphicsItem *origin, QGraphics
                 QGraphicsSceneTouchEvent::TouchPoint *touchPoint = touchEvent->touchPoints().at(i);
                 itemForTouchPointId[touchPoint->id()] = item;
             }
-            if (origin != item)
-                itemCurrentTouchPoints.remove(origin);
-            itemCurrentTouchPoints[item] = touchEvent->touchPoints();
             break;
         }
     }
diff --git a/src/gui/graphicsview/qgraphicsscene_p.h b/src/gui/graphicsview/qgraphicsscene_p.h
index 22feb4c..4af35a0 100644
--- a/src/gui/graphicsview/qgraphicsscene_p.h
+++ b/src/gui/graphicsview/qgraphicsscene_p.h
@@ -280,15 +280,11 @@ public:
     mutable QVector<int> freeSceneTransformSlots;
 
     QList<QGraphicsSceneTouchEvent::TouchPoint *> sceneCurrentTouchPoints;
-    QHash<QGraphicsItem *, QList<QGraphicsSceneTouchEvent::TouchPoint *> > itemCurrentTouchPoints;
     QHash<int, QGraphicsItem *> itemForTouchPointId;
     static void updateTouchPointsForItem(QGraphicsItem *item, QGraphicsSceneTouchEvent *touchEvent);
-    static QGraphicsSceneTouchEvent::TouchPoint *findClosestTouchPoint(const QList<QGraphicsSceneTouchEvent::TouchPoint *> &activeTouchPoints,
-                                                                       const QPointF &scenePos);
-    void appendTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint,
-                          QList<QGraphicsSceneTouchEvent::TouchPoint *> *currentTouchPoints);
-    void removeTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint,
-                          QList<QGraphicsSceneTouchEvent::TouchPoint *> *currentTouchPoints);
+    QGraphicsSceneTouchEvent::TouchPoint *findClosestTouchPoint(const QPointF &scenePos);
+    void appendTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint);
+    void removeTouchPoint(QGraphicsSceneTouchEvent::TouchPoint *touchPoint);
     void touchEventHandler(QGraphicsSceneTouchEvent *touchEvent);
     bool sendTouchBeginEvent(QGraphicsItem *item, QGraphicsSceneTouchEvent *touchEvent);
 };
diff --git a/src/gui/kernel/qapplication.cpp b/src/gui/kernel/qapplication.cpp
index 88b9a66..01c7c4a 100644
--- a/src/gui/kernel/qapplication.cpp
+++ b/src/gui/kernel/qapplication.cpp
@@ -4031,7 +4031,6 @@ bool QApplication::notify(QObject *receiver, QEvent *e)
     // Note: TouchUpdate and TouchEnd events are sent to d->currentMultitouchWidget and never propagated
     {
         QWidget *widget = static_cast<QWidget *>(receiver);
-        QWidget *origin = widget;
         QTouchEvent *touchEvent = static_cast<QTouchEvent *>(e);
         bool eventAccepted = touchEvent->isAccepted();
         if (widget->testAttribute(Qt::WA_AcceptTouchEvents) && e->spontaneous()) {
@@ -4055,9 +4054,6 @@ bool QApplication::notify(QObject *receiver, QEvent *e)
                     QTouchEvent::TouchPoint *touchPoint = touchEvent->touchPoints().at(i);
                     d->widgetForTouchPointId[touchPoint->id()] = widget;
                 }
-                if (origin != widget)
-                    d->widgetCurrentTouchPoints.remove(origin);
-                d->widgetCurrentTouchPoints[widget] = touchEvent->touchPoints();
                 break;
             } else if (widget->isWindow() || widget->testAttribute(Qt::WA_NoMousePropagation)) {
                 break;
diff --git a/src/gui/kernel/qapplication_p.h b/src/gui/kernel/qapplication_p.h
index 34395c9..1424611 100644
--- a/src/gui/kernel/qapplication_p.h
+++ b/src/gui/kernel/qapplication_p.h
@@ -435,7 +435,6 @@ public:
     QMap<QString, int> grabbedGestures;
 
     QHash<int, QWidget *> widgetForTouchPointId;
-    QMap<QWidget *, QList<QTouchEvent::TouchPoint *> > widgetCurrentTouchPoints;
     static void updateTouchPointsForWidget(QWidget *widget, QTouchEvent *touchEvent);
 
 #if defined(Q_WS_WIN)
@@ -448,12 +447,9 @@ public:
     QList<QTouchEvent::TouchPoint *> appCurrentTouchPoints;
 
     void initializeMultitouch();
-    static QTouchEvent::TouchPoint *findClosestTouchPoint(const QList<QTouchEvent::TouchPoint *> &activeTouchPoints,
-                                                          const QPointF &screenPos);
-    void appendTouchPoint(QTouchEvent::TouchPoint *touchPoint,
-                          QList<QTouchEvent::TouchPoint *> *currentTouchPoints);
-    void removeTouchPoint(QTouchEvent::TouchPoint *touchPoint,
-                          QList<QTouchEvent::TouchPoint *> *currentTouchPoints);
+    QTouchEvent::TouchPoint *findClosestTouchPoint(const QPointF &screenPos);
+    void appendTouchPoint(QTouchEvent::TouchPoint *touchPoint);
+    void removeTouchPoint(QTouchEvent::TouchPoint *touchPoint);
     bool translateTouchEvent(const MSG &msg);
 #endif
 
diff --git a/src/gui/kernel/qapplication_win.cpp b/src/gui/kernel/qapplication_win.cpp
index 0fc76ae..f980f8e 100644
--- a/src/gui/kernel/qapplication_win.cpp
+++ b/src/gui/kernel/qapplication_win.cpp
@@ -3989,19 +3989,17 @@ void QApplicationPrivate::initializeMultitouch()
     CloseTouchInputHandle = static_cast<qt_CloseTouchInputHandlePtr>(library.resolve("CloseTouchInputHandle"));
 
     widgetForTouchPointId.clear();
-    widgetCurrentTouchPoints.clear();
     touchInputIDToTouchPointID.clear();
     appAllTouchPoints.clear();
     appCurrentTouchPoints.clear();
 }
 
-QTouchEvent::TouchPoint *QApplicationPrivate::findClosestTouchPoint(const QList<QTouchEvent::TouchPoint *> &appActiveTouchPoints,
-                                                                    const QPointF &screenPos)
+QTouchEvent::TouchPoint *QApplicationPrivate::findClosestTouchPoint(const QPointF &screenPos)
 {
     QTouchEvent::TouchPoint *closestTouchPoint = 0;
     qreal closestDistance;
-    for (int i = 0; i < appActiveTouchPoints.count(); ++i) {
-        QTouchEvent::TouchPoint *touchPoint = appActiveTouchPoints.at(i);
+    for (int i = 0; i < appCurrentTouchPoints.count(); ++i) {
+        QTouchEvent::TouchPoint *touchPoint = appCurrentTouchPoints.at(i);
         qreal distance = QLineF(screenPos, touchPoint->screenPos()).length();
         if (!closestTouchPoint || distance < closestDistance) {
             closestTouchPoint = touchPoint;
@@ -4011,22 +4009,15 @@ QTouchEvent::TouchPoint *QApplicationPrivate::findClosestTouchPoint(const QList<
     return closestTouchPoint;
 }
 
-void QApplicationPrivate::appendTouchPoint(QTouchEvent::TouchPoint *touchPoint,
-                                           QList<QTouchEvent::TouchPoint *> *currentTouchPoints)
-{
-    // insort touch point (for the app)
+void QApplicationPrivate::appendTouchPoint(QTouchEvent::TouchPoint *touchPoint)
+{    
+    // insort touch point
     int at = 0;
     for (; at < appCurrentTouchPoints.count(); ++at) {
         if (appCurrentTouchPoints.at(at)->id() > touchPoint->id())
             break;
     }
     appCurrentTouchPoints.insert(at, touchPoint);
-    // again, for the widget's currentTouchPoints
-    for (at = 0; at < currentTouchPoints->count(); ++at) {
-        if (currentTouchPoints->at(at)->id() > touchPoint->id())
-            break;
-    }
-    currentTouchPoints->insert(at, touchPoint);
 
     if (appCurrentTouchPoints.count() > appAllTouchPoints.count()) {
         qFatal("Qt: INTERNAL ERROR: appCurrentTouchPoints.count() (%d) > appAllTouchPoints.count() (%d)",
@@ -4035,8 +4026,7 @@ void QApplicationPrivate::appendTouchPoint(QTouchEvent::TouchPoint *touchPoint,
     }
 }
 
-void QApplicationPrivate::removeTouchPoint(QTouchEvent::TouchPoint *touchPoint,
-                                           QList<QTouchEvent::TouchPoint *> *currentTouchPoints)
+void QApplicationPrivate::removeTouchPoint(QTouchEvent::TouchPoint *touchPoint)
 {
     // remove touch point from all known touch points
     for (int i = qMin(appCurrentTouchPoints.count() - 1, touchPoint->id()); i >= 0; --i) {
@@ -4045,13 +4035,6 @@ void QApplicationPrivate::removeTouchPoint(QTouchEvent::TouchPoint *touchPoint,
             break;
         }
     }
-    // again, for the widget's currentTouchPoints
-    for (int i = qMin(currentTouchPoints->count() - 1, touchPoint->id()); i >= 0; --i) {
-        if (currentTouchPoints->at(i) == touchPoint) {
-            currentTouchPoints->removeAt(i);
-            break;
-        }
-    }
 }
 
 bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
@@ -4062,10 +4045,9 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
     if (!widgetForHwnd)
         return false;
 
-    QList<QTouchEvent::TouchPoint *> appActiveTouchPoints = appCurrentTouchPoints;
-
     typedef QPair<Qt::TouchPointStates, QList<QTouchEvent::TouchPoint *> > StatesAndTouchPoints;
     QHash<QWidget *, StatesAndTouchPoints> widgetsNeedingEvents;
+
     QVector<TOUCHINPUT> winTouchInputs(msg.wParam);
     memset(winTouchInputs.data(), 0, sizeof(TOUCHINPUT) * winTouchInputs.count());
     QApplicationPrivate::GetTouchInputInfo((HANDLE) msg.lParam, msg.wParam, winTouchInputs.data(), sizeof(TOUCHINPUT));
@@ -4090,14 +4072,13 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
         bool down = touchPoint->state() != Qt::TouchPointReleased;
         QPointF screenPos(qreal(touchInput.x) / qreal(100.), qreal(touchInput.y) / qreal(100.));
 
-        QList<QTouchEvent::TouchPoint *> activeTouchPoints;
         if (!down && (touchInput.dwFlags & TOUCHEVENTF_DOWN)) {
             // determine which widget this event will go to
             widget = widgetForHwnd->childAt(widgetForHwnd->mapFromGlobal(screenPos.toPoint()));
             if (!widget)
                 widget = widgetForHwnd;
 
-            QTouchEvent::TouchPoint *closestTouchPoint = findClosestTouchPoint(appActiveTouchPoints, screenPos);
+            QTouchEvent::TouchPoint *closestTouchPoint = findClosestTouchPoint(screenPos);
             if (closestTouchPoint) {
                 QWidget *closestWidget = widgetForTouchPointId.value(closestTouchPoint->id());
                 if (closestWidget
@@ -4107,11 +4088,7 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
             }
             widgetForTouchPointId[touchPoint->id()] = widget;
 
-            QList<QTouchEvent::TouchPoint *> &currentTouchPoints = widgetCurrentTouchPoints[widget];
-            appendTouchPoint(touchPoint, &currentTouchPoints);
-            // make sure new points are added to activeTouchPoints as well
-            appActiveTouchPoints = appCurrentTouchPoints;
-            activeTouchPoints = currentTouchPoints;
+            appendTouchPoint(touchPoint);
 
             touchPoint->setState(Qt::TouchPointPressed);
             touchPoint->setScreenPos(screenPos);
@@ -4120,10 +4097,8 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
             touchPoint->setPressure(qreal(1.));
         } else if (down && (touchInput.dwFlags & TOUCHEVENTF_UP)) {
             widget = widgetForTouchPointId.take(touchPoint->id());
-            QList<QTouchEvent::TouchPoint *> &currentTouchPoints = widgetCurrentTouchPoints[widget];
-            appActiveTouchPoints = appCurrentTouchPoints;
-            activeTouchPoints = currentTouchPoints;
-            removeTouchPoint(touchPoint, &currentTouchPoints);
+
+            removeTouchPoint(touchPoint);
 
             touchPoint->setState(Qt::TouchPointReleased);
             touchPoint->setLastScreenPos(touchPoint->screenPos());
@@ -4131,8 +4106,7 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
             touchPoint->setPressure(qreal(0.));
         } else if (down) {
             widget = widgetForTouchPointId.value(touchPoint->id());
-            appActiveTouchPoints = appCurrentTouchPoints;
-            activeTouchPoints = widgetCurrentTouchPoints.value(widget);
+
             touchPoint->setState(screenPos == touchPoint->screenPos()
                                  ? Qt::TouchPointStationary
                                  : Qt::TouchPointMoved);
@@ -4144,7 +4118,7 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
 
         StatesAndTouchPoints &maskAndPoints = widgetsNeedingEvents[widget];
         maskAndPoints.first |= touchPoint->state();
-        maskAndPoints.second = activeTouchPoints;
+        maskAndPoints.second.append(touchPoint);
     }
     QApplicationPrivate::CloseTouchInputHandle((HANDLE) msg.lParam);
 
@@ -4194,14 +4168,6 @@ bool QApplicationPrivate::translateTouchEvent(const MSG &msg)
             returnValue = returnValue || (qt_tabletChokeMouse = qt_tabletChokeMouse || res);
             break;
         }
-        case QEvent::TouchEnd:
-        {
-            QList<QTouchEvent::TouchPoint *> currentTouchPoints = widgetCurrentTouchPoints.take(widget);
-            if (!currentTouchPoints.isEmpty()) {
-                qFatal("Qt: INTERNAL ERROR, the widget's currentTouchPoints should be empty!");
-            }
-            // fall-through intended
-        }
         default:
             if (widget->testAttribute(Qt::WA_AcceptedTouchBeginEvent)) {
                 (void) QApplication::sendSpontaneousEvent(widget, &touchEvent);