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** ensure the GNU Lesser General Public License version 2.1 requirements
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** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
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#include "qquickwindow.h"
#include "qquickwindow_p.h"

#include "qquickitem.h"
#include "qquickitem_p.h"
#include "qquickevents_p_p.h"

#include <QtQuick/private/qsgrenderer_p.h>
#include <QtQuick/private/qsgtexture_p.h>
#include <QtQuick/private/qsgflashnode_p.h>

#include <private/qquickwindowmanager_p.h>

#include <private/qguiapplication_p.h>
#include <QtGui/QInputMethod>

#include <private/qabstractanimation_p.h>

#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 <QtQml/qqmlincubator.h>

#include <QtQuick/private/qquickpixmapcache_p.h>

#include <private/qqmlprofilerservice_p.h>
#include <private/qqmlmemoryprofiler_p.h>

QT_BEGIN_NAMESPACE

void QQuickWindowPrivate::updateFocusItemTransform()
{
    Q_Q(QQuickWindow);
#ifndef QT_NO_IM
    QQuickItem *focus = q->activeFocusItem();
    if (focus && qApp->focusObject() == focus)
        qApp->inputMethod()->setInputItemTransform(QQuickItemPrivate::get(focus)->itemToWindowTransform());
#endif
}


class QQuickWindowIncubationController : public QObject, public QQmlIncubationController
{
    Q_OBJECT

public:
    QQuickWindowIncubationController(const QQuickWindow *window)
        : m_window(QQuickWindowPrivate::get(const_cast<QQuickWindow *>(window)))
    {
        // Allow incubation for 1/3 of a frame.
        m_incubation_time = qMax(1, int(1000 / QGuiApplication::primaryScreen()->refreshRate()) / 3);

        m_animation_driver = m_window->windowManager->animationDriver();
        if (m_animation_driver) {
            connect(m_animation_driver, SIGNAL(stopped()), this, SLOT(animationStopped()));
            connect(window, SIGNAL(frameSwapped()), this, SLOT(incubate()));
        }
    }

protected:
    virtual bool event(QEvent *e)
    {
        if (e->type() == QEvent::User) {
            incubate();
            return true;
        }
        return QObject::event(e);
    }

public slots:
    void incubate() {
        if (incubatingObjectCount()) {
            if (m_animation_driver && m_animation_driver->isRunning()) {
                incubateFor(m_incubation_time);
            } else {
                incubateFor(m_incubation_time * 2);
                if (incubatingObjectCount())
                    QCoreApplication::postEvent(this, new QEvent(QEvent::User));
            }
        }
    }

    void animationStopped() { incubate(); }

protected:
    virtual void incubatingObjectCountChanged(int count)
    {
        if (count && (!m_animation_driver || !m_animation_driver->isRunning()))
            QCoreApplication::postEvent(this, new QEvent(QEvent::User));
    }

private:
    QQuickWindowPrivate *m_window;
    int m_incubation_time;
    QAnimationDriver *m_animation_driver;
};

#include "qquickwindow.moc"


#ifndef QT_NO_ACCESSIBILITY
/*!
    Returns an accessibility interface for this window, or 0 if such an
    interface cannot be created.

    \warning The caller is responsible for deleting the returned interface.
*/
QAccessibleInterface *QQuickWindow::accessibleRoot() const
{
    return QAccessible::queryAccessibleInterface(const_cast<QQuickWindow*>(this));
}
#endif


/*
Focus behavior
==============

Prior to being added to a valid window items can set and clear focus with no
effect.  Only once items are added to a window (by way of having a parent set that
already belongs to a window) do the focus rules apply.  Focus goes back to
having no effect if an item is removed from a window.

When an item is moved into a new focus scope (either being added to a window
for the first time, or having its parent changed), if the focus scope already has
a scope focused item that takes precedence over the item being added.  Otherwise,
the focus of the added tree is used.  In the case of of a tree of items being
added to a window for the first time, which may have a conflicted focus state (two
or more items in one scope having focus set), the same rule is applied item by item -
thus the first item that has focus will get it (assuming the scope doesn't already
have a scope focused item), and the other items will have their focus cleared.
*/


// #define FOCUS_DEBUG
// #define MOUSE_DEBUG
// #define TOUCH_DEBUG
// #define DIRTY_DEBUG

#ifdef FOCUS_DEBUG
void printFocusTree(QQuickItem *item, QQuickItem *scope = 0, int depth = 1);
#endif

QQuickItem::UpdatePaintNodeData::UpdatePaintNodeData()
: transformNode(0)
{
}

QQuickRootItem::QQuickRootItem()
{
}

/*! \reimp */
void QQuickWindow::exposeEvent(QExposeEvent *)
{
    Q_D(QQuickWindow);
    d->windowManager->exposureChanged(this);
}

/*! \reimp */
void QQuickWindow::resizeEvent(QResizeEvent *)
{
    Q_D(QQuickWindow);
    d->windowManager->resize(this, size());
}

/*! \reimp */
void QQuickWindow::showEvent(QShowEvent *)
{
    d_func()->windowManager->show(this);
}

/*! \reimp */
void QQuickWindow::hideEvent(QHideEvent *)
{
    d_func()->windowManager->hide(this);
}

/*! \reimp */
void QQuickWindow::focusOutEvent(QFocusEvent *)
{
    Q_D(QQuickWindow);
    d->contentItem->setFocus(false);
}

/*! \reimp */
void QQuickWindow::focusInEvent(QFocusEvent *)
{
    Q_D(QQuickWindow);
    d->contentItem->setFocus(true);
    d->updateFocusItemTransform();
}


void QQuickWindowPrivate::polishItems()
{
    int maxPolishCycles = 100000;

    while (!itemsToPolish.isEmpty() && --maxPolishCycles > 0) {
        QSet<QQuickItem *> itms = itemsToPolish;
        itemsToPolish.clear();

        for (QSet<QQuickItem *>::iterator it = itms.begin(); it != itms.end(); ++it) {
            QQuickItem *item = *it;
            QQuickItemPrivate::get(item)->polishScheduled = false;
            item->updatePolish();
        }
    }

    if (maxPolishCycles == 0)
        qWarning("QQuickWindow: possible QQuickItem::polish() loop");

    updateFocusItemTransform();
}

/**
 * This parameter enables that this window can be rendered without
 * being shown on screen. This feature is very limited in what it supports.
 *
 * For this feature to be useful one needs to hook into beforeRender()
 * and set the render target.
 *
 */
void QQuickWindowPrivate::setRenderWithoutShowing(bool render)
{
    if (render == renderWithoutShowing)
        return;

    Q_Q(QQuickWindow);
    renderWithoutShowing = render;

    if (render)
        windowManager->show(q);
    else
        windowManager->hide(q);
}


/*!
 * Schedules the window to render another frame.
 *
 * Calling QQuickWindow::update() differs from QQuickItem::update() in that
 * it always triggers a repaint, regardless of changes in the underlying
 * scene graph or not.
 */
void QQuickWindow::update()
{
    Q_D(QQuickWindow);
    d->windowManager->update(this);
}

void forceUpdate(QQuickItem *item)
{
    if (item->flags() & QQuickItem::ItemHasContents)
        item->update();
    QQuickItemPrivate::get(item)->dirty(QQuickItemPrivate::ChildrenUpdateMask);

    QList <QQuickItem *> items = item->childItems();
    for (int i=0; i<items.size(); ++i)
        forceUpdate(items.at(i));
}

void QQuickWindowPrivate::syncSceneGraph()
{
    QML_MEMORY_SCOPE_STRING("SceneGraph");
    Q_Q(QQuickWindow);

    emit q->beforeSynchronizing();
    if (!renderer) {
        forceUpdate(contentItem);

        QSGRootNode *rootNode = new QSGRootNode;
        rootNode->appendChildNode(QQuickItemPrivate::get(contentItem)->itemNode());
        renderer = context->createRenderer();
        renderer->setRootNode(rootNode);
    }

    updateDirtyNodes();

    // Copy the current state of clearing from window into renderer.
    renderer->setClearColor(clearColor);
    QSGRenderer::ClearMode mode = QSGRenderer::ClearStencilBuffer | QSGRenderer::ClearDepthBuffer;
    if (clearBeforeRendering)
        mode |= QSGRenderer::ClearColorBuffer;
    renderer->setClearMode(mode);
}


void QQuickWindowPrivate::renderSceneGraph(const QSize &size)
{
    QML_MEMORY_SCOPE_STRING("SceneGraph");
    Q_Q(QQuickWindow);
    emit q->beforeRendering();
    int fboId = 0;
    const qreal devicePixelRatio = q->devicePixelRatio();
    renderer->setDeviceRect(QRect(QPoint(0, 0), size * devicePixelRatio));
    if (renderTargetId) {
        fboId = renderTargetId;
        renderer->setViewportRect(QRect(QPoint(0, 0), renderTargetSize));
    } else {
        renderer->setViewportRect(QRect(QPoint(0, 0), size * devicePixelRatio));
    }
    renderer->setProjectionMatrixToRect(QRect(QPoint(0, 0), size));

    context->renderNextFrame(renderer, fboId);
    emit q->afterRendering();
}

QQuickWindowPrivate::QQuickWindowPrivate()
    : contentItem(0)
    , activeFocusItem(0)
    , mouseGrabberItem(0)
#ifndef QT_NO_CURSOR
    , cursorItem(0)
#endif
    , touchMouseId(-1)
    , touchMousePressTimestamp(0)
    , renderWithoutShowing(false)
    , dirtyItemList(0)
    , context(0)
    , renderer(0)
    , windowManager(0)
    , clearColor(Qt::white)
    , clearBeforeRendering(true)
    , persistentGLContext(false)
    , persistentSceneGraph(false)
    , lastWheelEventAccepted(false)
    , renderTarget(0)
    , renderTargetId(0)
    , incubationController(0)
{
}

QQuickWindowPrivate::~QQuickWindowPrivate()
{
}

void QQuickWindowPrivate::init(QQuickWindow *c)
{
    q_ptr = c;

    Q_Q(QQuickWindow);

    contentItem = new QQuickRootItem;
    QQmlEngine::setObjectOwnership(contentItem, QQmlEngine::CppOwnership);
    QQuickItemPrivate *contentItemPrivate = QQuickItemPrivate::get(contentItem);
    contentItemPrivate->window = q;
    contentItemPrivate->windowRefCount = 1;
    contentItemPrivate->flags |= QQuickItem::ItemIsFocusScope;

    // In the absence of a focus in event on some platforms assume the window will
    // be activated immediately and set focus on the contentItem
    // ### Remove when QTBUG-22415 is resolved.
    //It is important that this call happens after the contentItem has a window..
    contentItem->setFocus(true);

    windowManager = QQuickWindowManager::instance();
    context = windowManager->sceneGraphContext();
    q->setSurfaceType(QWindow::OpenGLSurface);
    q->setFormat(context->defaultSurfaceFormat());

    QObject::connect(context, SIGNAL(initialized()), q, SIGNAL(sceneGraphInitialized()), Qt::DirectConnection);
    QObject::connect(context, SIGNAL(invalidated()), q, SIGNAL(sceneGraphInvalidated()), Qt::DirectConnection);
    QObject::connect(context, SIGNAL(invalidated()), q, SLOT(cleanupSceneGraph()), Qt::DirectConnection);
}

/*!
    \property QQuickWindow::data
    \internal
*/

QQmlListProperty<QObject> QQuickWindowPrivate::data()
{
    initContentItem();
    return QQuickItemPrivate::get(contentItem)->data();
}

void QQuickWindowPrivate::initContentItem()
{
    Q_Q(QQuickWindow);
    q->connect(q, SIGNAL(widthChanged(int)),
            contentItem, SLOT(setWidth(int)));
    q->connect(q, SIGNAL(heightChanged(int)),
            contentItem, SLOT(setHeight(int)));
    contentItem->setWidth(q->width());
    contentItem->setHeight(q->height());
}

static QMouseEvent *touchToMouseEvent(QEvent::Type type, const QTouchEvent::TouchPoint &p, QTouchEvent *event, QQuickItem *item, bool transformNeeded = true)
{
    // The touch point local position and velocity are not yet transformed.
    QMouseEvent *me = new QMouseEvent(type, transformNeeded ? item->mapFromScene(p.scenePos()) : p.pos(), p.scenePos(), p.screenPos(),
                                      Qt::LeftButton, Qt::LeftButton, event->modifiers());
    me->setAccepted(true);
    me->setTimestamp(event->timestamp());
    QVector2D transformedVelocity = p.velocity();
    if (transformNeeded) {
        QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);
        QMatrix4x4 transformMatrix(itemPrivate->windowToItemTransform());
        transformedVelocity = transformMatrix.mapVector(p.velocity()).toVector2D();
    }
    QGuiApplicationPrivate::setMouseEventCapsAndVelocity(me, event->device()->capabilities(), transformedVelocity);
    return me;
}

bool QQuickWindowPrivate::translateTouchToMouse(QQuickItem *item, QTouchEvent *event)
{
    Q_Q(QQuickWindow);
    // For each point, check if it is accepted, if not, try the next point.
    // Any of the fingers can become the mouse one.
    // This can happen because a mouse area might not accept an event at some point but another.
    for (int i = 0; i < event->touchPoints().count(); ++i) {
        const QTouchEvent::TouchPoint &p = event->touchPoints().at(i);
        // A new touch point
        if (touchMouseId == -1 && p.state() & Qt::TouchPointPressed) {
            QPointF pos = item->mapFromScene(p.scenePos());

            // probably redundant, we check bounds in the calling function (matchingNewPoints)
            if (!item->contains(pos))
                break;

            bool doubleClick = event->timestamp() - touchMousePressTimestamp
                            < static_cast<ulong>(qApp->styleHints()->mouseDoubleClickInterval());
            touchMousePressTimestamp = event->timestamp();
            // Store the id already here and restore it to -1 if the event does not get
            // accepted. Cannot defer setting the new value because otherwise if the event
            // handler spins the event loop all subsequent moves and releases get lost.
            touchMouseId = p.id();
            itemForTouchPointId[touchMouseId] = item;
            QScopedPointer<QMouseEvent> mousePress(touchToMouseEvent(QEvent::MouseButtonPress, p, event, item));

            // Send a single press and see if that's accepted
            if (!mouseGrabberItem)
                item->grabMouse();
            item->grabTouchPoints(QVector<int>() << touchMouseId);

            q->sendEvent(item, mousePress.data());
            event->setAccepted(mousePress->isAccepted());
            if (!mousePress->isAccepted()) {
                touchMouseId = -1;
                if (itemForTouchPointId.value(p.id()) == item)
                    itemForTouchPointId.remove(p.id());

                if (mouseGrabberItem == item)
                    item->ungrabMouse();
            }

            if (doubleClick && mousePress->isAccepted()) {
                touchMousePressTimestamp = 0;
                QScopedPointer<QMouseEvent> mouseDoubleClick(touchToMouseEvent(QEvent::MouseButtonDblClick, p, event, item));
                q->sendEvent(item, mouseDoubleClick.data());
                event->setAccepted(mouseDoubleClick->isAccepted());
                if (mouseDoubleClick->isAccepted()) {
                    return true;
                } else {
                    touchMouseId = -1;
                }
            }
            // The event was accepted, we are done.
            if (mousePress->isAccepted())
                return true;
            // The event was not accepted but touchMouseId was set.
            if (touchMouseId != -1)
                return false;
            // try the next point

        // Touch point was there before and moved
        } else if (p.id() == touchMouseId) {
            if (p.state() & Qt::TouchPointMoved) {
                if (mouseGrabberItem) {
                    QScopedPointer<QMouseEvent> me(touchToMouseEvent(QEvent::MouseMove, p, event, mouseGrabberItem));
                    q->sendEvent(mouseGrabberItem, me.data());
                    event->setAccepted(me->isAccepted());
                    if (me->isAccepted()) {
                        itemForTouchPointId[p.id()] = mouseGrabberItem; // N.B. the mouseGrabberItem may be different after returning from sendEvent()
                        return true;
                    }
                } else {
                    // no grabber, check if we care about mouse hover
                    // FIXME: this should only happen once, not recursively... I'll ignore it just ignore hover now.
                    // hover for touch???
                    QScopedPointer<QMouseEvent> me(touchToMouseEvent(QEvent::MouseMove, p, event, item));
                    if (lastMousePosition.isNull())
                        lastMousePosition = me->windowPos();
                    QPointF last = lastMousePosition;
                    lastMousePosition = me->windowPos();

                    bool accepted = me->isAccepted();
                    bool delivered = deliverHoverEvent(contentItem, me->windowPos(), last, me->modifiers(), accepted);
                    if (!delivered) {
                        //take care of any exits
                        accepted = clearHover();
                    }
                    me->setAccepted(accepted);
                    break;
                }
            } else if (p.state() & Qt::TouchPointReleased) {
                // currently handled point was released
                touchMouseId = -1;
                if (mouseGrabberItem) {
                    QScopedPointer<QMouseEvent> me(touchToMouseEvent(QEvent::MouseButtonRelease, p, event, mouseGrabberItem));
                    q->sendEvent(mouseGrabberItem, me.data());
                    if (mouseGrabberItem) // might have ungrabbed due to event
                        mouseGrabberItem->ungrabMouse();
                    return me->isAccepted();
                }
            }
            break;
        }
    }
    return false;
}

void QQuickWindowPrivate::transformTouchPoints(QList<QTouchEvent::TouchPoint> &touchPoints, const QTransform &transform)
{
    QMatrix4x4 transformMatrix(transform);
    for (int i=0; i<touchPoints.count(); i++) {
        QTouchEvent::TouchPoint &touchPoint = touchPoints[i];
        touchPoint.setRect(transform.mapRect(touchPoint.sceneRect()));
        touchPoint.setStartPos(transform.map(touchPoint.startScenePos()));
        touchPoint.setLastPos(transform.map(touchPoint.lastScenePos()));
        touchPoint.setVelocity(transformMatrix.mapVector(touchPoint.velocity()).toVector2D());
    }
}


/*!
Translates the data in \a touchEvent to this window.  This method leaves the item local positions in
\a touchEvent untouched (these are filled in later).
*/
void QQuickWindowPrivate::translateTouchEvent(QTouchEvent *touchEvent)
{
    QList<QTouchEvent::TouchPoint> touchPoints = touchEvent->touchPoints();
    for (int i = 0; i < touchPoints.count(); ++i) {
        QTouchEvent::TouchPoint &touchPoint = touchPoints[i];

        touchPoint.setScreenRect(touchPoint.sceneRect());
        touchPoint.setStartScreenPos(touchPoint.startScenePos());
        touchPoint.setLastScreenPos(touchPoint.lastScenePos());

        touchPoint.setSceneRect(touchPoint.rect());
        touchPoint.setStartScenePos(touchPoint.startPos());
        touchPoint.setLastScenePos(touchPoint.lastPos());

        if (i == 0)
            lastMousePosition = touchPoint.pos().toPoint();
    }
    touchEvent->setTouchPoints(touchPoints);
}

void QQuickWindowPrivate::setFocusInScope(QQuickItem *scope, QQuickItem *item, FocusOptions options)
{
    Q_Q(QQuickWindow);

    Q_ASSERT(item);
    Q_ASSERT(scope || item == contentItem);

#ifdef FOCUS_DEBUG
    qWarning() << "QQuickWindowPrivate::setFocusInScope():";
    qWarning() << "    scope:" << (QObject *)scope;
    if (scope)
        qWarning() << "    scopeSubFocusItem:" << (QObject *)QQuickItemPrivate::get(scope)->subFocusItem;
    qWarning() << "    item:" << (QObject *)item;
    qWarning() << "    activeFocusItem:" << (QObject *)activeFocusItem;
#endif

    QQuickItemPrivate *scopePrivate = scope ? QQuickItemPrivate::get(scope) : 0;
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

    QQuickItem *oldActiveFocusItem = 0;
    QQuickItem *newActiveFocusItem = 0;

    QVarLengthArray<QQuickItem *, 20> changed;

    // Does this change the active focus?
    if (item == contentItem || (scopePrivate->activeFocus && item->isEnabled())) {
        oldActiveFocusItem = activeFocusItem;
        newActiveFocusItem = item;
        while (newActiveFocusItem->isFocusScope()
               && newActiveFocusItem->scopedFocusItem()
               && newActiveFocusItem->scopedFocusItem()->isEnabled()) {
            newActiveFocusItem = newActiveFocusItem->scopedFocusItem();
        }

        if (oldActiveFocusItem) {
#ifndef QT_NO_IM
            qApp->inputMethod()->commit();
#endif

            activeFocusItem = 0;
            QFocusEvent event(QEvent::FocusOut, Qt::OtherFocusReason);
            q->sendEvent(oldActiveFocusItem, &event);

            QQuickItem *afi = oldActiveFocusItem;
            while (afi && afi != scope) {
                if (QQuickItemPrivate::get(afi)->activeFocus) {
                    QQuickItemPrivate::get(afi)->activeFocus = false;
                    changed << afi;
                }
                afi = afi->parentItem();
            }
        }
    }

    if (item != contentItem && !(options & DontChangeSubFocusItem)) {
        QQuickItem *oldSubFocusItem = scopePrivate->subFocusItem;
        if (oldSubFocusItem) {
            QQuickItemPrivate::get(oldSubFocusItem)->focus = false;
            changed << oldSubFocusItem;
        }

        QQuickItemPrivate::get(item)->updateSubFocusItem(scope, true);
    }

    if (!(options & DontChangeFocusProperty)) {
//        if (item != contentItem || QGuiApplication::focusWindow() == q) {    // QTBUG-22415
            itemPrivate->focus = true;
            changed << item;
//        }
    }

    if (newActiveFocusItem && contentItem->hasFocus()) {
        activeFocusItem = newActiveFocusItem;

        QQuickItemPrivate::get(newActiveFocusItem)->activeFocus = true;
        changed << newActiveFocusItem;

        QQuickItem *afi = newActiveFocusItem->parentItem();
        while (afi && afi != scope) {
            if (afi->isFocusScope()) {
                QQuickItemPrivate::get(afi)->activeFocus = true;
                changed << afi;
            }
            afi = afi->parentItem();
        }

        QFocusEvent event(QEvent::FocusIn, Qt::OtherFocusReason);
        q->sendEvent(newActiveFocusItem, &event);
    }

    emit q->focusObjectChanged(activeFocusItem);

    if (!changed.isEmpty())
        notifyFocusChangesRecur(changed.data(), changed.count() - 1);
}

void QQuickWindowPrivate::clearFocusInScope(QQuickItem *scope, QQuickItem *item, FocusOptions options)
{
    Q_Q(QQuickWindow);

    Q_ASSERT(item);
    Q_ASSERT(scope || item == contentItem);

#ifdef FOCUS_DEBUG
    qWarning() << "QQuickWindowPrivate::clearFocusInScope():";
    qWarning() << "    scope:" << (QObject *)scope;
    qWarning() << "    item:" << (QObject *)item;
    qWarning() << "    activeFocusItem:" << (QObject *)activeFocusItem;
#endif

    QQuickItemPrivate *scopePrivate = 0;
    if (scope) {
        scopePrivate = QQuickItemPrivate::get(scope);
        if ( !scopePrivate->subFocusItem )
            return;//No focus, nothing to do.
    }

    QQuickItem *oldActiveFocusItem = 0;
    QQuickItem *newActiveFocusItem = 0;

    QVarLengthArray<QQuickItem *, 20> changed;

    Q_ASSERT(item == contentItem || item == scopePrivate->subFocusItem);

    // Does this change the active focus?
    if (item == contentItem || scopePrivate->activeFocus) {
        oldActiveFocusItem = activeFocusItem;
        newActiveFocusItem = scope;

        Q_ASSERT(oldActiveFocusItem);

#ifndef QT_NO_IM
        qApp->inputMethod()->commit();
#endif

        activeFocusItem = 0;
        QFocusEvent event(QEvent::FocusOut, Qt::OtherFocusReason);
        q->sendEvent(oldActiveFocusItem, &event);

        QQuickItem *afi = oldActiveFocusItem;
        while (afi && afi != scope) {
            if (QQuickItemPrivate::get(afi)->activeFocus) {
                QQuickItemPrivate::get(afi)->activeFocus = false;
                changed << afi;
            }
            afi = afi->parentItem();
        }
    }

    if (item != contentItem && !(options & DontChangeSubFocusItem)) {
        QQuickItem *oldSubFocusItem = scopePrivate->subFocusItem;
        if (oldSubFocusItem && !(options & DontChangeFocusProperty)) {
            QQuickItemPrivate::get(oldSubFocusItem)->focus = false;
            changed << oldSubFocusItem;
        }

        QQuickItemPrivate::get(item)->updateSubFocusItem(scope, false);

    } else if (!(options & DontChangeFocusProperty)) {
        QQuickItemPrivate::get(item)->focus = false;
        changed << item;
    }

    if (newActiveFocusItem) {
        Q_ASSERT(newActiveFocusItem == scope);
        activeFocusItem = scope;

        QFocusEvent event(QEvent::FocusIn, Qt::OtherFocusReason);
        q->sendEvent(newActiveFocusItem, &event);
    }

    emit q->focusObjectChanged(activeFocusItem);

    if (!changed.isEmpty())
        notifyFocusChangesRecur(changed.data(), changed.count() - 1);
}

void QQuickWindowPrivate::notifyFocusChangesRecur(QQuickItem **items, int remaining)
{
    QQmlGuard<QQuickItem> item(*items);

    if (remaining)
        notifyFocusChangesRecur(items + 1, remaining - 1);

    if (item) {
        QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

        if (itemPrivate->notifiedFocus != itemPrivate->focus) {
            itemPrivate->notifiedFocus = itemPrivate->focus;
            emit item->focusChanged(itemPrivate->focus);
        }

        if (item && itemPrivate->notifiedActiveFocus != itemPrivate->activeFocus) {
            itemPrivate->notifiedActiveFocus = itemPrivate->activeFocus;
            itemPrivate->itemChange(QQuickItem::ItemActiveFocusHasChanged, itemPrivate->activeFocus);
            emit item->activeFocusChanged(itemPrivate->activeFocus);
        }
    }
}

void QQuickWindowPrivate::dirtyItem(QQuickItem *)
{
    Q_Q(QQuickWindow);
    q->maybeUpdate();
}

void QQuickWindowPrivate::cleanup(QSGNode *n)
{
    Q_Q(QQuickWindow);

    Q_ASSERT(!cleanupNodeList.contains(n));
    cleanupNodeList.append(n);
    q->maybeUpdate();
}

/*!
    \qmltype Window
    \instantiates QQuickWindow
    \inqmlmodule QtQuick.Window 2
    \ingroup qtquick-visual
    \brief Creates a new top-level window

    The Window object creates a new top-level window for a QtQuick scene. It automatically sets up the
    window for use with QtQuick 2.0 graphical types.

    To use this type, you will need to import the module with the following line:
    \code
    import QtQuick.Window 2.0
    \endcode

    Restricting this import will allow you to have a QML environment without access to window system features.
*/
/*!
    \class QQuickWindow
    \since QtQuick 2.0

    \inmodule QtQuick

    \brief The QQuickWindow class provides the window for displaying a graphical QML scene

    QQuickWindow provides the graphical scene management needed to interact with and display
    a scene of QQuickItems.

    A QQuickWindow always has a single invisible root item. To add items to this window,
    reparent the items to the root item or to an existing item in the scene.

    For easily displaying a scene from a QML file, see \l{QQuickView}.

    \section1 Scene Graph and Rendering

    The QQuickWindow uses a scene graph on top of OpenGL to render. This scene graph is disconnected
    from the QML scene and potentially lives in another thread, depending on the platform
    implementation. Since the rendering scene graph lives independently from the QML scene, it can
    also be completely released without affecting the state of the QML scene.

    The sceneGraphInitialized() signal is emitted on the rendering thread before the QML scene is
    rendered to the screen for the first time. If the rendering scene graph has been released
    the signal will be emitted again before the next frame is rendered.

    The rendering of each frame is broken down into the following
    steps, in the given order:

    \list 1

    \li The QQuickWindow::beforeSynchronizing() signal is emitted.
    Applications can make direct connections (Qt::DirectConnection)
    to this signal to do any preparation required before calls to
    QQuickItem::updatePaintNode().

    \li Synchronization of the QML state into the scene graph. This is
    done by calling the QQuickItem::updatePaintNode() function on all
    items that have changed since the previous frame. When a dedicated
    rendering thread is used, the GUI thread is blocked during this
    synchroniation. This is the only time the QML items and the nodes
    in the scene graph interact.

    \li The window to be rendered is made current using
    QOpenGLContext::makeCurrent().

    \li The QQuickWindow::beforeRendering() signal is
    emitted. Applications can make direct connections
    (Qt::DirectConnection) to this signal to use custom OpenGL calls
    which will then stack visually beneath the QML scene.

    \li Items that have specified QSGNode::UsesPreprocess, will have their
    QSGNode::preprocess() function invoked.

    \li The QQuickWindow is cleared according to what is specified
    using QQuickWindow::setClearBeforeRendering() and
    QQuickWindow::setClearColor().

    \li The scene graph is rendered.

    \li The QQuickWindow::afterRendering() signal is
    emitted. Applications can make direct connections
    (Qt::DirectConnection) to this signal to use custom OpenGL calls
    which will then stack visually over the QML scene.

    \li The rendered frame is swapped and QQuickWindow::frameSwapped()
    is emitted.

    \endlist

    All of the above happen on the rendering thread, when applicable.

    While the scene graph is being rendered on the rendering thread, the GUI will process animations
    for the next frame. This means that as long as users are not using scene graph API
    directly, the added complexity of a rendering thread can be completely ignored.

    When a QQuickWindow is programatically hidden with hide() or setVisible(false), it will
    stop rendering and its scene graph and OpenGL context might be released. The
    sceneGraphInvalidated() signal will be emitted when this happens.

    \warning It is crucial that OpenGL operations and interaction with the scene graph happens
    exclusively on the rendering thread, primarily during the updatePaintNode() phase.

    \warning As signals related to rendering might be emitted from the rendering thread,
    connections should be made using Qt::DirectConnection


    \section2 Resource Management

    QML will typically try to cache images, scene graph nodes, etc to improve performance, but in
    some low-memory scenarios it might be required to aggressively release these resources. The
    releaseResources() can be used to force clean up of certain resources. Calling releaseResources()
    may result in the entire scene graph and its OpenGL context being deleted. The
    sceneGraphInvalidated() signal will be emitted when this happens.

    \sa {OpenGL Under QML Example}

*/

/*!
    Constructs a window for displaying a QML scene with parent window \a parent.
*/
QQuickWindow::QQuickWindow(QWindow *parent)
    : QWindow(*(new QQuickWindowPrivate), parent)
{
    Q_D(QQuickWindow);
    d->init(this);
}

/*!
    \internal
*/
QQuickWindow::QQuickWindow(QQuickWindowPrivate &dd, QWindow *parent)
    : QWindow(dd, parent)
{
    Q_D(QQuickWindow);
    d->init(this);
}

/*!
    Destroys the window.
*/
QQuickWindow::~QQuickWindow()
{
    Q_D(QQuickWindow);

    d->windowManager->windowDestroyed(this);

    QCoreApplication::sendPostedEvents(0, QEvent::DeferredDelete);
    delete d->incubationController; d->incubationController = 0;

    delete d->contentItem; d->contentItem = 0;
}



/*!
    This function tries to release redundant resources currently held by the QML scene.

    Calling this function might result in the scene graph and the OpenGL context used
    for rendering being released to release graphics memory. If this happens, the
    sceneGraphInvalidated() signal will be called, allowing users to clean up their
    own graphics resources. The setPersistentOpenGLContext() and setPersistentSceneGraph()
    functions can be used to prevent this from happening, if handling the cleanup is
    not feasible in the application, at the cost of higher memory usage.

    \sa sceneGraphInvalidated(), setPersistentOpenGLContext(), setPersistentSceneGraph()
 */

void QQuickWindow::releaseResources()
{
    Q_D(QQuickWindow);
    d->windowManager->releaseResources();
    QQuickPixmap::purgeCache();
}



/*!
    Sets whether the OpenGL context can be released as a part of a call to
    releaseResources() to \a persistent.

    The OpenGL context might still be released when the user makes an explicit
    call to hide().

    \sa setPersistentSceneGraph()
 */

void QQuickWindow::setPersistentOpenGLContext(bool persistent)
{
    Q_D(QQuickWindow);
    d->persistentGLContext = persistent;
}


/*!
    Returns whether the OpenGL context can be released as a part of a call to
    releaseResources().
 */

bool QQuickWindow::isPersistentOpenGLContext() const
{
    Q_D(const QQuickWindow);
    return d->persistentGLContext;
}



/*!
    Sets whether the scene graph nodes and resources can be released as a
    part of a call to releaseResources() to \a persistent.

    The scene graph nodes and resources might still be released when the user
    makes an explicit call to hide().

    \sa setPersistentOpenGLContext()
 */

void QQuickWindow::setPersistentSceneGraph(bool persistent)
{
    Q_D(QQuickWindow);
    d->persistentSceneGraph = persistent;
}



/*!
    Returns whether the scene graph nodes and resources can be released as a part
    of a call to releaseResources().
 */

bool QQuickWindow::isPersistentSceneGraph() const
{
    Q_D(const QQuickWindow);
    return d->persistentSceneGraph;
}





/*!
    \property QQuickWindow::contentItem
    \brief The invisible root item of the scene.

  A QQuickWindow always has a single invisible root item containing all of its content.
  To add items to this window, reparent the items to the contentItem or to an existing
  item in the scene.
*/
QQuickItem *QQuickWindow::contentItem() const
{
    Q_D(const QQuickWindow);

    return d->contentItem;
}

/*!
  Returns the item which currently has active focus.
*/
QQuickItem *QQuickWindow::activeFocusItem() const
{
    Q_D(const QQuickWindow);

    return d->activeFocusItem;
}

/*!
  \internal
  \reimp
*/
QObject *QQuickWindow::focusObject() const
{
    Q_D(const QQuickWindow);

    if (d->activeFocusItem)
        return d->activeFocusItem;
    return const_cast<QQuickWindow*>(this);
}


/*!
  Returns the item which currently has the mouse grab.
*/
QQuickItem *QQuickWindow::mouseGrabberItem() const
{
    Q_D(const QQuickWindow);

    return d->mouseGrabberItem;
}


bool QQuickWindowPrivate::clearHover()
{
    Q_Q(QQuickWindow);
    if (hoverItems.isEmpty())
        return false;

    QPointF pos = q->mapFromGlobal(QGuiApplicationPrivate::lastCursorPosition.toPoint());

    bool accepted = false;
    foreach (QQuickItem* item, hoverItems)
        accepted = sendHoverEvent(QEvent::HoverLeave, item, pos, pos, QGuiApplication::keyboardModifiers(), true) || accepted;
    hoverItems.clear();
    return accepted;
}

/*! \reimp */
bool QQuickWindow::event(QEvent *e)
{
    Q_D(QQuickWindow);

    switch (e->type()) {

    case QEvent::TouchBegin:
    case QEvent::TouchUpdate:
    case QEvent::TouchEnd: {
        QTouchEvent *touch = static_cast<QTouchEvent*>(e);
        d->translateTouchEvent(touch);
        // return in order to avoid the QWindow::event below
        return d->deliverTouchEvent(touch);
    }
        break;
    case QEvent::TouchCancel:
        // return in order to avoid the QWindow::event below
        return d->deliverTouchCancelEvent(static_cast<QTouchEvent*>(e));
        break;
    case QEvent::Leave:
        d->clearHover();
        d->lastMousePosition = QPoint();
        if (d->mouseGrabberItem)
            d->mouseGrabberItem->ungrabMouse();
        break;
#ifndef QT_NO_DRAGANDDROP
    case QEvent::DragEnter:
    case QEvent::DragLeave:
    case QEvent::DragMove:
    case QEvent::Drop:
        d->deliverDragEvent(&d->dragGrabber, e);
        break;
#endif
    case QEvent::WindowDeactivate:
        contentItem()->windowDeactivateEvent();
        break;
    case QEvent::FocusAboutToChange:
#ifndef QT_NO_IM
        if (d->activeFocusItem)
            qGuiApp->inputMethod()->commit();
#endif
        break;
    default:
        break;
    }

    return QWindow::event(e);
}

/*! \reimp */
void QQuickWindow::keyPressEvent(QKeyEvent *e)
{
    Q_D(QQuickWindow);

    if (d->activeFocusItem)
        sendEvent(d->activeFocusItem, e);
}

/*! \reimp */
void QQuickWindow::keyReleaseEvent(QKeyEvent *e)
{
    Q_D(QQuickWindow);

    if (d->activeFocusItem)
        sendEvent(d->activeFocusItem, e);
}

QMouseEvent *QQuickWindowPrivate::cloneMouseEvent(QMouseEvent *event, QPointF *transformedLocalPos)
{
    int caps = QGuiApplicationPrivate::mouseEventCaps(event);
    QVector2D velocity = QGuiApplicationPrivate::mouseEventVelocity(event);
    QMouseEvent *me = new QMouseEvent(event->type(),
                                      transformedLocalPos ? *transformedLocalPos : event->localPos(),
                                      event->windowPos(), event->screenPos(),
                                      event->button(), event->buttons(), event->modifiers());
    QGuiApplicationPrivate::setMouseEventCapsAndVelocity(me, caps, velocity);
    me->setTimestamp(event->timestamp());
    return me;
}

bool QQuickWindowPrivate::deliverInitialMousePressEvent(QQuickItem *item, QMouseEvent *event)
{
    Q_Q(QQuickWindow);

    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

    if (itemPrivate->flags & QQuickItem::ItemClipsChildrenToShape) {
        QPointF p = item->mapFromScene(event->windowPos());
        if (!item->contains(p))
            return false;
    }

    QList<QQuickItem *> children = itemPrivate->paintOrderChildItems();
    for (int ii = children.count() - 1; ii >= 0; --ii) {
        QQuickItem *child = children.at(ii);
        if (!child->isVisible() || !child->isEnabled() || QQuickItemPrivate::get(child)->culled)
            continue;
        if (deliverInitialMousePressEvent(child, event))
            return true;
    }

    if (itemPrivate->acceptedMouseButtons() & event->button()) {
        QPointF localPos = item->mapFromScene(event->windowPos());
        if (item->contains(localPos)) {
            QScopedPointer<QMouseEvent> me(cloneMouseEvent(event, &localPos));
            me->accept();
            item->grabMouse();
            q->sendEvent(item, me.data());
            event->setAccepted(me->isAccepted());
            if (me->isAccepted())
                return true;
            if (mouseGrabberItem && !event->buttons())
                mouseGrabberItem->ungrabMouse();
        }
    }

    return false;
}

bool QQuickWindowPrivate::deliverMouseEvent(QMouseEvent *event)
{
    Q_Q(QQuickWindow);

    lastMousePosition = event->windowPos();

    if (!mouseGrabberItem &&
         event->type() == QEvent::MouseButtonPress &&
         (event->buttons() & event->button()) == event->buttons()) {
        if (deliverInitialMousePressEvent(contentItem, event))
            event->accept();
        else
            event->ignore();
        return event->isAccepted();
    }

    if (mouseGrabberItem) {
        QPointF localPos = mouseGrabberItem->mapFromScene(event->windowPos());
        QScopedPointer<QMouseEvent> me(cloneMouseEvent(event, &localPos));
        me->accept();
        q->sendEvent(mouseGrabberItem, me.data());
        event->setAccepted(me->isAccepted());
        if (me->isAccepted())
            return true;
    }

    return false;
}

/*! \reimp */
void QQuickWindow::mousePressEvent(QMouseEvent *event)
{
    Q_D(QQuickWindow);
#ifdef MOUSE_DEBUG
    qWarning() << "QQuickWindow::mousePressEvent()" << event->localPos() << event->button() << event->buttons();
#endif

    d->deliverMouseEvent(event);
}

/*! \reimp */
void QQuickWindow::mouseReleaseEvent(QMouseEvent *event)
{
    Q_D(QQuickWindow);
#ifdef MOUSE_DEBUG
    qWarning() << "QQuickWindow::mouseReleaseEvent()" << event->localPos() << event->button() << event->buttons();
#endif

    if (!d->mouseGrabberItem) {
        QWindow::mouseReleaseEvent(event);
        return;
    }

    d->deliverMouseEvent(event);
    if (d->mouseGrabberItem && !event->buttons())
        d->mouseGrabberItem->ungrabMouse();
}

/*! \reimp */
void QQuickWindow::mouseDoubleClickEvent(QMouseEvent *event)
{
    Q_D(QQuickWindow);
#ifdef MOUSE_DEBUG
    qWarning() << "QQuickWindow::mouseDoubleClickEvent()" << event->localPos() << event->button() << event->buttons();
#endif

    if (!d->mouseGrabberItem && (event->buttons() & event->button()) == event->buttons()) {
        if (d->deliverInitialMousePressEvent(d->contentItem, event))
            event->accept();
        else
            event->ignore();
        return;
    }

    d->deliverMouseEvent(event);
}

bool QQuickWindowPrivate::sendHoverEvent(QEvent::Type type, QQuickItem *item,
                                      const QPointF &scenePos, const QPointF &lastScenePos,
                                      Qt::KeyboardModifiers modifiers, bool accepted)
{
    Q_Q(QQuickWindow);
    const QTransform transform = QQuickItemPrivate::get(item)->windowToItemTransform();

    //create copy of event
    QHoverEvent hoverEvent(type, transform.map(scenePos), transform.map(lastScenePos), modifiers);
    hoverEvent.setAccepted(accepted);

    q->sendEvent(item, &hoverEvent);

    return hoverEvent.isAccepted();
}

/*! \reimp */
void QQuickWindow::mouseMoveEvent(QMouseEvent *event)
{
    Q_D(QQuickWindow);
#ifdef MOUSE_DEBUG
    qWarning() << "QQuickWindow::mouseMoveEvent()" << event->localPos() << event->button() << event->buttons();
#endif

#ifndef QT_NO_CURSOR
    d->updateCursor(event->windowPos());
#endif

    if (!d->mouseGrabberItem) {
        if (d->lastMousePosition.isNull())
            d->lastMousePosition = event->windowPos();
        QPointF last = d->lastMousePosition;
        d->lastMousePosition = event->windowPos();

        bool accepted = event->isAccepted();
        bool delivered = d->deliverHoverEvent(d->contentItem, event->windowPos(), last, event->modifiers(), accepted);
        if (!delivered) {
            //take care of any exits
            accepted = d->clearHover();
        }
        event->setAccepted(accepted);
        return;
    }

    d->deliverMouseEvent(event);
}

bool QQuickWindowPrivate::deliverHoverEvent(QQuickItem *item, const QPointF &scenePos, const QPointF &lastScenePos,
                                         Qt::KeyboardModifiers modifiers, bool &accepted)
{
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

    if (itemPrivate->flags & QQuickItem::ItemClipsChildrenToShape) {
        QPointF p = item->mapFromScene(scenePos);
        if (!item->contains(p))
            return false;
    }

    QList<QQuickItem *> children = itemPrivate->paintOrderChildItems();
    for (int ii = children.count() - 1; ii >= 0; --ii) {
        QQuickItem *child = children.at(ii);
        if (!child->isVisible() || !child->isEnabled() || QQuickItemPrivate::get(child)->culled)
            continue;
        if (deliverHoverEvent(child, scenePos, lastScenePos, modifiers, accepted))
            return true;
    }

    if (itemPrivate->hoverEnabled) {
        QPointF p = item->mapFromScene(scenePos);
        if (item->contains(p)) {
            if (!hoverItems.isEmpty() && hoverItems[0] == item) {
                //move
                accepted = sendHoverEvent(QEvent::HoverMove, item, scenePos, lastScenePos, modifiers, accepted);
            } else {
                QList<QQuickItem *> itemsToHover;
                QQuickItem* parent = item;
                itemsToHover << item;
                while ((parent = parent->parentItem()))
                    itemsToHover << parent;

                // Leaving from previous hovered items until we reach the item or one of its ancestors.
                while (!hoverItems.isEmpty() && !itemsToHover.contains(hoverItems[0])) {
                    sendHoverEvent(QEvent::HoverLeave, hoverItems[0], scenePos, lastScenePos, modifiers, accepted);
                    hoverItems.removeFirst();
                }

                if (!hoverItems.isEmpty() && hoverItems[0] == item){//Not entering a new Item
                    // ### Shouldn't we send moves for the parent items as well?
                    accepted = sendHoverEvent(QEvent::HoverMove, item, scenePos, lastScenePos, modifiers, accepted);
                } else {
                    // Enter items that are not entered yet.
                    int startIdx = -1;
                    if (!hoverItems.isEmpty())
                        startIdx = itemsToHover.indexOf(hoverItems[0]) - 1;
                    if (startIdx == -1)
                        startIdx = itemsToHover.count() - 1;

                    for (int i = startIdx; i >= 0; i--) {
                        QQuickItem *itemToHover = itemsToHover[i];
                        if (QQuickItemPrivate::get(itemToHover)->hoverEnabled) {
                            hoverItems.prepend(itemToHover);
                            sendHoverEvent(QEvent::HoverEnter, itemToHover, scenePos, lastScenePos, modifiers, accepted);
                        }
                    }
                }
            }
            return true;
        }
    }

    return false;
}

#ifndef QT_NO_WHEELEVENT
bool QQuickWindowPrivate::deliverWheelEvent(QQuickItem *item, QWheelEvent *event)
{
    Q_Q(QQuickWindow);
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

    if (itemPrivate->flags & QQuickItem::ItemClipsChildrenToShape) {
        QPointF p = item->mapFromScene(event->posF());
        if (!item->contains(p))
            return false;
    }

    QList<QQuickItem *> children = itemPrivate->paintOrderChildItems();
    for (int ii = children.count() - 1; ii >= 0; --ii) {
        QQuickItem *child = children.at(ii);
        if (!child->isVisible() || !child->isEnabled() || QQuickItemPrivate::get(child)->culled)
            continue;
        if (deliverWheelEvent(child, event))
            return true;
    }

    QPointF p = item->mapFromScene(event->posF());

    if (item->contains(p)) {
        QWheelEvent wheel(p, p, event->pixelDelta(), event->angleDelta(), event->delta(),
                          event->orientation(), event->buttons(), event->modifiers());
        wheel.accept();
        q->sendEvent(item, &wheel);
        if (wheel.isAccepted()) {
            event->accept();
            return true;
        }
    }

    return false;
}

/*! \reimp */
void QQuickWindow::wheelEvent(QWheelEvent *event)
{
    Q_D(QQuickWindow);
#ifdef MOUSE_DEBUG
    qWarning() << "QQuickWindow::wheelEvent()" << event->pixelDelta() << event->angleDelta();
#endif

    //if the actual wheel event was accepted, accept the compatibility wheel event and return early
    if (d->lastWheelEventAccepted && event->angleDelta().isNull())
        return;

    event->ignore();
    d->deliverWheelEvent(d->contentItem, event);
    d->lastWheelEventAccepted = event->isAccepted();
}
#endif // QT_NO_WHEELEVENT


bool QQuickWindowPrivate::deliverTouchCancelEvent(QTouchEvent *event)
{
#ifdef TOUCH_DEBUG
    qWarning("touchCancelEvent");
#endif
    Q_Q(QQuickWindow);
    // A TouchCancel event will typically not contain any points.
    // Deliver it to all items that have active touches.
    QSet<QQuickItem *> cancelDelivered;
    foreach (QQuickItem *item, itemForTouchPointId) {
        if (cancelDelivered.contains(item))
            continue;
        cancelDelivered.insert(item);
        q->sendEvent(item, event);
    }
    touchMouseId = -1;
    if (mouseGrabberItem)
        mouseGrabberItem->ungrabMouse();
    // The next touch event can only be a TouchBegin so clean up.
    itemForTouchPointId.clear();
    return true;
}

// check what kind of touch we have (begin/update) and
// call deliverTouchPoints to actually dispatch the points
bool QQuickWindowPrivate::deliverTouchEvent(QTouchEvent *event)
{
#ifdef TOUCH_DEBUG
    if (event->type() == QEvent::TouchBegin)
        qWarning() << "touchBeginEvent";
    else if (event->type() == QEvent::TouchUpdate)
        qWarning() << "touchUpdateEvent points";
    else if (event->type() == QEvent::TouchEnd)
        qWarning("touchEndEvent");
#endif

    // List of all items that received an event before
    // When we have TouchBegin this is and will stay empty
    QHash<QQuickItem *, QList<QTouchEvent::TouchPoint> > updatedPoints;

    // Figure out who accepted a touch point last and put it in updatedPoints
    // Add additional item to newPoints
    const QList<QTouchEvent::TouchPoint> &touchPoints = event->touchPoints();
    QList<QTouchEvent::TouchPoint> newPoints;
    for (int i=0; i<touchPoints.count(); i++) {
        const QTouchEvent::TouchPoint &touchPoint = touchPoints.at(i);
        if (touchPoint.state() == Qt::TouchPointPressed) {
            newPoints << touchPoint;
        } else {
            // TouchPointStationary is relevant only to items which
            // are also receiving touch points with some other state.
            // But we have not yet decided which points go to which item,
            // so for now we must include all non-new points in updatedPoints.
            if (itemForTouchPointId.contains(touchPoint.id())) {
                QQuickItem *item = itemForTouchPointId.value(touchPoint.id());
                if (item)
                    updatedPoints[item].append(touchPoint);
            }
        }
    }

    // Deliver the event, but only if there is at least one new point
    // or some item accepted a point and should receive an update
    if (newPoints.count() > 0 || updatedPoints.count() > 0) {
        QSet<int> acceptedNewPoints;
        event->setAccepted(deliverTouchPoints(contentItem, event, newPoints, &acceptedNewPoints, &updatedPoints));
    } else
        event->ignore();

    // Remove released points from itemForTouchPointId
    if (event->touchPointStates() & Qt::TouchPointReleased) {
        for (int i=0; i<touchPoints.count(); i++) {
            if (touchPoints[i].state() == Qt::TouchPointReleased) {
                itemForTouchPointId.remove(touchPoints[i].id());
                if (touchPoints[i].id() == touchMouseId)
                    touchMouseId = -1;
            }
        }
    }

    if (event->type() == QEvent::TouchEnd) {
        Q_ASSERT(itemForTouchPointId.isEmpty());
    }

    return event->isAccepted();
}

// This function recurses and sends the events to the individual items
bool QQuickWindowPrivate::deliverTouchPoints(QQuickItem *item, QTouchEvent *event, const QList<QTouchEvent::TouchPoint> &newPoints, QSet<int> *acceptedNewPoints, QHash<QQuickItem *, QList<QTouchEvent::TouchPoint> > *updatedPoints)
{
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

    if (itemPrivate->flags & QQuickItem::ItemClipsChildrenToShape) {
        for (int i=0; i<newPoints.count(); i++) {
            QPointF p = item->mapFromScene(newPoints[i].scenePos());
            if (!item->contains(p))
                return false;
        }
    }

    // Check if our children want the event (or parts of it)
    // This is the only point where touch event delivery recurses!
    QList<QQuickItem *> children = itemPrivate->paintOrderChildItems();
    for (int ii = children.count() - 1; ii >= 0; --ii) {
        QQuickItem *child = children.at(ii);
        if (!child->isEnabled() || !child->isVisible() || QQuickItemPrivate::get(child)->culled)
            continue;
        if (deliverTouchPoints(child, event, newPoints, acceptedNewPoints, updatedPoints))
            return true;
    }

    // None of the children accepted the event, so check the given item itself.
    // First, construct matchingPoints as a list of TouchPoints which the
    // given item might be interested in.  Any newly-pressed point which is
    // inside the item's bounds will be interesting, and also any updated point
    // which was already accepted by that item when it was first pressed.
    // (A point which was already accepted is effectively "grabbed" by the item.)

    // set of IDs of "interesting" new points
    QSet<int> matchingNewPoints;
    // set of points which this item has previously accepted, for starters
    QList<QTouchEvent::TouchPoint> matchingPoints = (*updatedPoints)[item];
    // now add the new points which are inside this item's bounds
    if (newPoints.count() > 0 && acceptedNewPoints->count() < newPoints.count()) {
        for (int i = 0; i < newPoints.count(); i++) {
            if (acceptedNewPoints->contains(newPoints[i].id()))
                continue;
            QPointF p = item->mapFromScene(newPoints[i].scenePos());
            if (item->contains(p)) {
                matchingNewPoints.insert(newPoints[i].id());
                matchingPoints << newPoints[i];
            }
        }
    }
    // If there are no matching new points, and the existing points are all stationary,
    // there's no need to send an event to this item.  This is required by a test in
    // tst_qquickwindow::touchEvent_basic:
    // a single stationary press on an item shouldn't cause an event
    if (matchingNewPoints.isEmpty()) {
        bool stationaryOnly = true;
        Q_FOREACH (QTouchEvent::TouchPoint tp, matchingPoints)
            if (tp.state() != Qt::TouchPointStationary)
                stationaryOnly = false;
        if (stationaryOnly)
            matchingPoints.clear();
    }

    if (!matchingPoints.isEmpty()) {
        // Now we know this item might be interested in the event. Copy and send it, but
        // with only the subset of TouchPoints which are relevant to that item: that's matchingPoints.
        QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);
        transformTouchPoints(matchingPoints, itemPrivate->windowToItemTransform());
        deliverMatchingPointsToItem(item, event, acceptedNewPoints, matchingNewPoints, matchingPoints);
    }

    // record the fact that this item has been visited already
    updatedPoints->remove(item);

    // recursion is done only if ALL touch points have been delivered
    return (acceptedNewPoints->count() == newPoints.count() && updatedPoints->isEmpty());
}

// touchEventForItemBounds has no means to generate a touch event that contains
// only the points that are relevant for this item.  Thus the need for
// matchingPoints to already be that set of interesting points.
// They are all pre-transformed, too.
bool QQuickWindowPrivate::deliverMatchingPointsToItem(QQuickItem *item, QTouchEvent *event, QSet<int> *acceptedNewPoints, const QSet<int> &matchingNewPoints, const QList<QTouchEvent::TouchPoint> &matchingPoints)
{
    QScopedPointer<QTouchEvent> touchEvent(touchEventWithPoints(*event, matchingPoints));
    touchEvent.data()->setTarget(item);
    bool touchEventAccepted = false;

    // First check whether the parent wants to be a filter,
    // and if the parent accepts the event we are done.
    if (sendFilteredTouchEvent(item->parentItem(), item, event)) {
        event->accept();
        return true;
    }

    // Since it can change in sendEvent, update itemForTouchPointId now
    foreach (int id, matchingNewPoints)
        itemForTouchPointId[id] = item;

    // Deliver the touch event to the given item
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);
    itemPrivate->deliverTouchEvent(touchEvent.data());
    touchEventAccepted = touchEvent->isAccepted();

    // If the touch event wasn't accepted, synthesize a mouse event and see if the item wants it.
    if (!touchEventAccepted && (itemPrivate->acceptedMouseButtons() & Qt::LeftButton)) {
        //  send mouse event
        event->setAccepted(translateTouchToMouse(item, event));
        if (event->isAccepted()) {
            touchEventAccepted = true;
        }
    }

    if (touchEventAccepted) {
        // If the touch was accepted (regardless by whom or in what form),
        // update acceptedNewPoints.
        foreach (int id, matchingNewPoints)
            acceptedNewPoints->insert(id);
    } else {
        // But if the event was not accepted then we know this item
        // will not be interested in further updates for those touchpoint IDs either.
        foreach (int id, matchingNewPoints)
            if (itemForTouchPointId[id] == item)
                itemForTouchPointId.remove(id);
    }

    return touchEventAccepted;
}

QTouchEvent *QQuickWindowPrivate::touchEventForItemBounds(QQuickItem *target, const QTouchEvent &originalEvent)
{
    const QList<QTouchEvent::TouchPoint> &touchPoints = originalEvent.touchPoints();
    QList<QTouchEvent::TouchPoint> pointsInBounds;
    // if all points are stationary, the list of points should be empty to signal a no-op
    if (originalEvent.touchPointStates() != Qt::TouchPointStationary) {
        for (int i = 0; i < touchPoints.count(); ++i) {
            const QTouchEvent::TouchPoint &tp = touchPoints.at(i);
            if (tp.state() == Qt::TouchPointPressed) {
                QPointF p = target->mapFromScene(tp.scenePos());
                if (target->contains(p))
                    pointsInBounds.append(tp);
            } else {
                pointsInBounds.append(tp);
            }
        }
        transformTouchPoints(pointsInBounds, QQuickItemPrivate::get(target)->windowToItemTransform());
    }

    QTouchEvent* touchEvent = touchEventWithPoints(originalEvent, pointsInBounds);
    touchEvent->setTarget(target);
    return touchEvent;
}

QTouchEvent *QQuickWindowPrivate::touchEventWithPoints(const QTouchEvent &event, const QList<QTouchEvent::TouchPoint> &newPoints)
{
    Qt::TouchPointStates eventStates;
    for (int i=0; i<newPoints.count(); i++)
        eventStates |= newPoints[i].state();
    // if all points have the same state, set the event type accordingly
    QEvent::Type eventType = event.type();
    switch (eventStates) {
        case Qt::TouchPointPressed:
            eventType = QEvent::TouchBegin;
            break;
        case Qt::TouchPointReleased:
            eventType = QEvent::TouchEnd;
            break;
        default:
            eventType = QEvent::TouchUpdate;
            break;
    }

    QTouchEvent *touchEvent = new QTouchEvent(eventType);
    touchEvent->setWindow(event.window());
    touchEvent->setTarget(event.target());
    touchEvent->setDevice(event.device());
    touchEvent->setModifiers(event.modifiers());
    touchEvent->setTouchPoints(newPoints);
    touchEvent->setTouchPointStates(eventStates);
    touchEvent->setTimestamp(event.timestamp());
    touchEvent->accept();
    return touchEvent;
}

#ifndef QT_NO_DRAGANDDROP
void QQuickWindowPrivate::deliverDragEvent(QQuickDragGrabber *grabber, QEvent *event)
{
    Q_Q(QQuickWindow);
    grabber->resetTarget();
    QQuickDragGrabber::iterator grabItem = grabber->begin();
    if (grabItem != grabber->end()) {
        Q_ASSERT(event->type() != QEvent::DragEnter);
        if (event->type() == QEvent::Drop) {
            QDropEvent *e = static_cast<QDropEvent *>(event);
            for (e->setAccepted(false); !e->isAccepted() && grabItem != grabber->end(); grabItem = grabber->release(grabItem)) {
                QPointF p = (**grabItem)->mapFromScene(e->pos());
                QDropEvent translatedEvent(
                        p.toPoint(),
                        e->possibleActions(),
                        e->mimeData(),
                        e->mouseButtons(),
                        e->keyboardModifiers());
                QQuickDropEventEx::copyActions(&translatedEvent, *e);
                q->sendEvent(**grabItem, &translatedEvent);
                e->setAccepted(translatedEvent.isAccepted());
                e->setDropAction(translatedEvent.dropAction());
                grabber->setTarget(**grabItem);
            }
        }
        if (event->type() != QEvent::DragMove) {    // Either an accepted drop or a leave.
            QDragLeaveEvent leaveEvent;
            for (; grabItem != grabber->end(); grabItem = grabber->release(grabItem))
                q->sendEvent(**grabItem, &leaveEvent);
            return;
        } else for (; grabItem != grabber->end(); grabItem = grabber->release(grabItem)) {
            QDragMoveEvent *moveEvent = static_cast<QDragMoveEvent *>(event);
            if (deliverDragEvent(grabber, **grabItem, moveEvent)) {
                moveEvent->setAccepted(true);
                for (++grabItem; grabItem != grabber->end();) {
                    QPointF p = (**grabItem)->mapFromScene(moveEvent->pos());
                    if ((**grabItem)->contains(p)) {
                        QDragMoveEvent translatedEvent(
                                p.toPoint(),
                                moveEvent->possibleActions(),
                                moveEvent->mimeData(),
                                moveEvent->mouseButtons(),
                                moveEvent->keyboardModifiers());
                        QQuickDropEventEx::copyActions(&translatedEvent, *moveEvent);
                        q->sendEvent(**grabItem, &translatedEvent);
                        ++grabItem;
                    } else {
                        QDragLeaveEvent leaveEvent;
                        q->sendEvent(**grabItem, &leaveEvent);
                        grabItem = grabber->release(grabItem);
                    }
                }
                return;
            } else {
                QDragLeaveEvent leaveEvent;
                q->sendEvent(**grabItem, &leaveEvent);
            }
        }
    }
    if (event->type() == QEvent::DragEnter || event->type() == QEvent::DragMove) {
        QDragMoveEvent *e = static_cast<QDragMoveEvent *>(event);
        QDragEnterEvent enterEvent(
                e->pos(),
                e->possibleActions(),
                e->mimeData(),
                e->mouseButtons(),
                e->keyboardModifiers());
        QQuickDropEventEx::copyActions(&enterEvent, *e);
        event->setAccepted(deliverDragEvent(grabber, contentItem, &enterEvent));
    }
}

bool QQuickWindowPrivate::deliverDragEvent(QQuickDragGrabber *grabber, QQuickItem *item, QDragMoveEvent *event)
{
    Q_Q(QQuickWindow);
    bool accepted = false;
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);
    if (!item->isVisible() || !item->isEnabled() || QQuickItemPrivate::get(item)->culled)
        return false;

    QPointF p = item->mapFromScene(event->pos());
    if (item->contains(p)) {
        if (event->type() == QEvent::DragMove || itemPrivate->flags & QQuickItem::ItemAcceptsDrops) {
            QDragMoveEvent translatedEvent(
                    p.toPoint(),
                    event->possibleActions(),
                    event->mimeData(),
                    event->mouseButtons(),
                    event->keyboardModifiers(),
                    event->type());
            QQuickDropEventEx::copyActions(&translatedEvent, *event);
            q->sendEvent(item, &translatedEvent);
            if (event->type() == QEvent::DragEnter) {
                if (translatedEvent.isAccepted()) {
                    grabber->grab(item);
                    accepted = true;
                }
            } else {
                accepted = true;
            }
        }
    } else if (itemPrivate->flags & QQuickItem::ItemClipsChildrenToShape) {
        return false;
    }

    QDragEnterEvent enterEvent(
            event->pos(),
            event->possibleActions(),
            event->mimeData(),
            event->mouseButtons(),
            event->keyboardModifiers());
    QQuickDropEventEx::copyActions(&enterEvent, *event);
    QList<QQuickItem *> children = itemPrivate->paintOrderChildItems();
    for (int ii = children.count() - 1; ii >= 0; --ii) {
        if (deliverDragEvent(grabber, children.at(ii), &enterEvent))
            return true;
    }

    return accepted;
}
#endif // QT_NO_DRAGANDDROP

#ifndef QT_NO_CURSOR
void QQuickWindowPrivate::updateCursor(const QPointF &scenePos)
{
    Q_Q(QQuickWindow);

    QQuickItem *oldCursorItem = cursorItem;
    cursorItem = findCursorItem(contentItem, scenePos);

    if (cursorItem != oldCursorItem) {
        if (cursorItem)
            q->setCursor(cursorItem->cursor());
        else
            q->unsetCursor();
    }
}

QQuickItem *QQuickWindowPrivate::findCursorItem(QQuickItem *item, const QPointF &scenePos)
{
    QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);
    if (itemPrivate->flags & QQuickItem::ItemClipsChildrenToShape) {
        QPointF p = item->mapFromScene(scenePos);
        if (!item->contains(p))
            return 0;
    }

    const int numCursorsInHierarchy = itemPrivate->extra.isAllocated() ? itemPrivate->extra.value().numItemsWithCursor : 0;
    const int numChildrenWithCursor = itemPrivate->hasCursor ? numCursorsInHierarchy-1 : numCursorsInHierarchy;

    if (numChildrenWithCursor > 0) {
        QList<QQuickItem *> children = itemPrivate->paintOrderChildItems();
        for (int ii = children.count() - 1; ii >= 0; --ii) {
            QQuickItem *child = children.at(ii);
            if (!child->isVisible() || !child->isEnabled() || QQuickItemPrivate::get(child)->culled)
                continue;
            if (QQuickItem *cursorItem = findCursorItem(child, scenePos))
                return cursorItem;
        }
    }

    if (itemPrivate->hasCursor) {
        QPointF p = item->mapFromScene(scenePos);
        if (item->contains(p))
            return item;
    }
    return 0;
}
#endif

bool QQuickWindowPrivate::sendFilteredTouchEvent(QQuickItem *target, QQuickItem *item, QTouchEvent *event)
{
    if (!target)
        return false;

    QQuickItemPrivate *targetPrivate = QQuickItemPrivate::get(target);
    if (targetPrivate->filtersChildMouseEvents) {
        QScopedPointer<QTouchEvent> targetEvent(touchEventForItemBounds(target, *event));
        if (!targetEvent->touchPoints().isEmpty()) {
            QVector<int> touchIds;
            for (int i = 0; i < event->touchPoints().size(); ++i)
                touchIds.append(event->touchPoints().at(i).id());
            if (target->childMouseEventFilter(item, targetEvent.data())) {
                target->grabTouchPoints(touchIds);
                if (mouseGrabberItem) {
                    mouseGrabberItem->ungrabMouse();
                    touchMouseId = -1;
                }
                return true;
            }

            // Only offer a mouse event to the filter if we have one point
            if (targetEvent->touchPoints().count() == 1) {
                QEvent::Type t;
                const QTouchEvent::TouchPoint &tp = targetEvent->touchPoints().first();
                switch (tp.state()) {
                case Qt::TouchPointPressed:
                    t = QEvent::MouseButtonPress;
                    break;
                case Qt::TouchPointReleased:
                    t = QEvent::MouseButtonRelease;
                    break;
                default:
                    // move or stationary
                    t = QEvent::MouseMove;
                    break;
                }

                // targetEvent is already transformed wrt local position, velocity, etc.
                QScopedPointer<QMouseEvent> mouseEvent(touchToMouseEvent(t, targetEvent->touchPoints().first(), event, item, false));
                if (target->childMouseEventFilter(item, mouseEvent.data())) {
                    itemForTouchPointId[tp.id()] = target;
                    touchMouseId = tp.id();
                    target->grabMouse();
                    return true;
                }
            }
        }
    }

    return sendFilteredTouchEvent(target->parentItem(), item, event);
}

bool QQuickWindowPrivate::sendFilteredMouseEvent(QQuickItem *target, QQuickItem *item, QEvent *event)
{
    if (!target)
        return false;

    QQuickItemPrivate *targetPrivate = QQuickItemPrivate::get(target);
    if (targetPrivate->filtersChildMouseEvents)
        if (target->childMouseEventFilter(item, event))
            return true;

    if (sendFilteredMouseEvent(target->parentItem(), item, event))
        return true;

    return false;
}

bool QQuickWindowPrivate::dragOverThreshold(qreal d, Qt::Axis axis, QMouseEvent *event)
{
    QStyleHints *styleHints = qApp->styleHints();
    int caps = QGuiApplicationPrivate::mouseEventCaps(event);
    bool dragVelocityLimitAvailable = (caps & QTouchDevice::Velocity)
        && styleHints->startDragVelocity();
    bool overThreshold = qAbs(d) > styleHints->startDragDistance();
    if (dragVelocityLimitAvailable) {
        QVector2D velocityVec = QGuiApplicationPrivate::mouseEventVelocity(event);
        qreal velocity = axis == Qt::XAxis ? velocityVec.x() : velocityVec.y();
        overThreshold |= qAbs(velocity) > styleHints->startDragVelocity();
    }
    return overThreshold;
}

bool QQuickWindowPrivate::isRenderable() const
{
    const QQuickWindow *q = q_func();
    QRect geom = q->geometry();
    if (geom.width() <= 0 || geom.height() <= 0)
        return false;
    // Change to be applied after the visibility property is integrated in qtbase:
//    return visibility != QWindow::Hidden || (renderWithoutShowing && platformWindow);
    // Temporary version which is implementation-agnostic but slightly less efficient:
    return q->isVisible() || (renderWithoutShowing && platformWindow);
}

/*!
    Propagates an event \a e to a QQuickItem \a item on the window.

    The return value is currently not used.
*/
bool QQuickWindow::sendEvent(QQuickItem *item, QEvent *e)
{
    Q_D(QQuickWindow);

    if (!item) {
        qWarning("QQuickWindow::sendEvent: Cannot send event to a null item");
        return false;
    }

    Q_ASSERT(e);

    switch (e->type()) {
    case QEvent::KeyPress:
    case QEvent::KeyRelease:
        e->accept();
        QQuickItemPrivate::get(item)->deliverKeyEvent(static_cast<QKeyEvent *>(e));
        while (!e->isAccepted() && (item = item->parentItem())) {
            e->accept();
            QQuickItemPrivate::get(item)->deliverKeyEvent(static_cast<QKeyEvent *>(e));
        }
        break;
    case QEvent::FocusIn:
    case QEvent::FocusOut:
        QQuickItemPrivate::get(item)->deliverFocusEvent(static_cast<QFocusEvent *>(e));
        break;
    case QEvent::MouseButtonPress:
    case QEvent::MouseButtonRelease:
    case QEvent::MouseButtonDblClick:
    case QEvent::MouseMove:
        // XXX todo - should sendEvent be doing this?  how does it relate to forwarded events?
        if (!d->sendFilteredMouseEvent(item->parentItem(), item, e)) {
            // accept because qml items by default accept and have to explicitly opt out of accepting
            e->accept();
            QQuickItemPrivate::get(item)->deliverMouseEvent(static_cast<QMouseEvent *>(e));
        }
        break;
    case QEvent::UngrabMouse:
        if (!d->sendFilteredMouseEvent(item->parentItem(), item, e)) {
            e->accept();
            item->mouseUngrabEvent();
        }
        break;
#ifndef QT_NO_WHEELEVENT
    case QEvent::Wheel:
        QQuickItemPrivate::get(item)->deliverWheelEvent(static_cast<QWheelEvent *>(e));
        break;
#endif
    case QEvent::HoverEnter:
    case QEvent::HoverLeave:
    case QEvent::HoverMove:
        QQuickItemPrivate::get(item)->deliverHoverEvent(static_cast<QHoverEvent *>(e));
        break;
    case QEvent::TouchBegin:
    case QEvent::TouchUpdate:
    case QEvent::TouchEnd:
        d->sendFilteredTouchEvent(item->parentItem(), item, static_cast<QTouchEvent *>(e));
        break;
    case QEvent::TouchCancel:
        QQuickItemPrivate::get(item)->deliverTouchEvent(static_cast<QTouchEvent *>(e));
        break;
#ifndef QT_NO_DRAGANDDROP
    case QEvent::DragEnter:
    case QEvent::DragMove:
    case QEvent::DragLeave:
    case QEvent::Drop:
        QQuickItemPrivate::get(item)->deliverDragEvent(e);
        break;
#endif
    default:
        break;
    }

    return false;
}

void QQuickWindowPrivate::cleanupNodes()
{
    for (int ii = 0; ii < cleanupNodeList.count(); ++ii)
        delete cleanupNodeList.at(ii);
    cleanupNodeList.clear();
}

void QQuickWindowPrivate::cleanupNodesOnShutdown(QQuickItem *item)
{
    QQuickItemPrivate *p = QQuickItemPrivate::get(item);
    if (p->itemNodeInstance) {
        delete p->itemNodeInstance;
        p->itemNodeInstance = 0;

        if (p->extra.isAllocated()) {
            p->extra->opacityNode = 0;
            p->extra->clipNode = 0;
            p->extra->rootNode = 0;
        }

        p->groupNode = 0;
        p->paintNode = 0;
    }

    for (int ii = 0; ii < p->childItems.count(); ++ii)
        cleanupNodesOnShutdown(p->childItems.at(ii));
}

// This must be called from the render thread, with the main thread frozen
void QQuickWindowPrivate::cleanupNodesOnShutdown()
{
    Q_Q(QQuickWindow);
    cleanupNodes();
    cleanupNodesOnShutdown(contentItem);
    QSet<QQuickItem *>::const_iterator it = parentlessItems.begin();
    for (; it != parentlessItems.end(); ++it)
        cleanupNodesOnShutdown(*it);
    q->cleanupSceneGraph();
}

void QQuickWindowPrivate::updateDirtyNodes()
{
#ifdef DIRTY_DEBUG
    qWarning() << "QQuickWindowPrivate::updateDirtyNodes():";
#endif

    cleanupNodes();

    QQuickItem *updateList = dirtyItemList;
    dirtyItemList = 0;
    if (updateList) QQuickItemPrivate::get(updateList)->prevDirtyItem = &updateList;

    while (updateList) {
        QQuickItem *item = updateList;
        QQuickItemPrivate *itemPriv = QQuickItemPrivate::get(item);
        itemPriv->removeFromDirtyList();

#ifdef DIRTY_DEBUG
        qWarning() << "   QSGNode:" << item << qPrintable(itemPriv->dirtyToString());
#endif
        updateDirtyNode(item);
    }
}

void QQuickWindowPrivate::updateDirtyNode(QQuickItem *item)
{
#ifdef QML_RUNTIME_TESTING
    bool didFlash = false;
#endif

    QQuickItemPrivate *itemPriv = QQuickItemPrivate::get(item);
    quint32 dirty = itemPriv->dirtyAttributes;
    itemPriv->dirtyAttributes = 0;

    if ((dirty & QQuickItemPrivate::TransformUpdateMask) ||
        (dirty & QQuickItemPrivate::Size && itemPriv->origin() != QQuickItem::TopLeft &&
         (itemPriv->scale() != 1. || itemPriv->rotation() != 0.))) {

        QMatrix4x4 matrix;

        if (itemPriv->x != 0. || itemPriv->y != 0.)
            matrix.translate(itemPriv->x, itemPriv->y);

        for (int ii = itemPriv->transforms.count() - 1; ii >= 0; --ii)
            itemPriv->transforms.at(ii)->applyTo(&matrix);

        if (itemPriv->scale() != 1. || itemPriv->rotation() != 0.) {
            QPointF origin = item->transformOriginPoint();
            matrix.translate(origin.x(), origin.y());
            if (itemPriv->scale() != 1.)
                matrix.scale(itemPriv->scale(), itemPriv->scale());
            if (itemPriv->rotation() != 0.)
                matrix.rotate(itemPriv->rotation(), 0, 0, 1);
            matrix.translate(-origin.x(), -origin.y());
        }

        itemPriv->itemNode()->setMatrix(matrix);
    }

    bool clipEffectivelyChanged = (dirty & (QQuickItemPrivate::Clip | QQuickItemPrivate::Window)) &&
                                  ((item->clip() == false) != (itemPriv->clipNode() == 0));
    int effectRefCount = itemPriv->extra.isAllocated()?itemPriv->extra->effectRefCount:0;
    bool effectRefEffectivelyChanged = (dirty & (QQuickItemPrivate::EffectReference | QQuickItemPrivate::Window)) &&
                                  ((effectRefCount == 0) != (itemPriv->rootNode() == 0));

    if (clipEffectivelyChanged) {
        QSGNode *parent = itemPriv->opacityNode() ? (QSGNode *) itemPriv->opacityNode() :
                                                    (QSGNode *)itemPriv->itemNode();
        QSGNode *child = itemPriv->rootNode() ? (QSGNode *)itemPriv->rootNode() :
                                                (QSGNode *)itemPriv->groupNode;

        if (item->clip()) {
            Q_ASSERT(itemPriv->clipNode() == 0);
            itemPriv->extra.value().clipNode = new QQuickDefaultClipNode(item->clipRect());
            itemPriv->clipNode()->update();

            if (child)
                parent->removeChildNode(child);
            parent->appendChildNode(itemPriv->clipNode());
            if (child)
                itemPriv->clipNode()->appendChildNode(child);

        } else {
            Q_ASSERT(itemPriv->clipNode() != 0);
            parent->removeChildNode(itemPriv->clipNode());
            if (child)
                itemPriv->clipNode()->removeChildNode(child);
            delete itemPriv->clipNode();
            itemPriv->extra->clipNode = 0;
            if (child)
                parent->appendChildNode(child);
        }
    }

    if (dirty & QQuickItemPrivate::ChildrenUpdateMask)
        itemPriv->childContainerNode()->removeAllChildNodes();

    if (effectRefEffectivelyChanged) {
        QSGNode *parent = itemPriv->clipNode();
        if (!parent)
            parent = itemPriv->opacityNode();
        if (!parent)
            parent = itemPriv->itemNode();
        QSGNode *child = itemPriv->groupNode;

        if (itemPriv->extra.isAllocated() && itemPriv->extra->effectRefCount) {
            Q_ASSERT(itemPriv->rootNode() == 0);
            itemPriv->extra->rootNode = new QSGRootNode;

            if (child)
                parent->removeChildNode(child);
            parent->appendChildNode(itemPriv->rootNode());
            if (child)
                itemPriv->rootNode()->appendChildNode(child);
        } else {
            Q_ASSERT(itemPriv->rootNode() != 0);
            parent->removeChildNode(itemPriv->rootNode());
            if (child)
                itemPriv->rootNode()->removeChildNode(child);
            delete itemPriv->rootNode();
            itemPriv->extra->rootNode = 0;
            if (child)
                parent->appendChildNode(child);
        }
    }

    if (dirty & QQuickItemPrivate::ChildrenUpdateMask) {
        QSGNode *groupNode = itemPriv->groupNode;
        if (groupNode)
            groupNode->removeAllChildNodes();

        QList<QQuickItem *> orderedChildren = itemPriv->paintOrderChildItems();
        int ii = 0;

        for (; ii < orderedChildren.count() && orderedChildren.at(ii)->z() < 0; ++ii) {
            QQuickItemPrivate *childPrivate = QQuickItemPrivate::get(orderedChildren.at(ii));
            if (!childPrivate->explicitVisible &&
                (!childPrivate->extra.isAllocated() || !childPrivate->extra->effectRefCount))
                continue;
            if (childPrivate->itemNode()->parent())
                childPrivate->itemNode()->parent()->removeChildNode(childPrivate->itemNode());

            itemPriv->childContainerNode()->appendChildNode(childPrivate->itemNode());
        }

        QSGNode *beforePaintNode = itemPriv->groupNode ? itemPriv->groupNode->lastChild() : 0;
        if (beforePaintNode || itemPriv->extra.isAllocated())
            itemPriv->extra.value().beforePaintNode = beforePaintNode;

        if (itemPriv->paintNode)
            itemPriv->childContainerNode()->appendChildNode(itemPriv->paintNode);

        for (; ii < orderedChildren.count(); ++ii) {
            QQuickItemPrivate *childPrivate = QQuickItemPrivate::get(orderedChildren.at(ii));
            if (!childPrivate->explicitVisible &&
                (!childPrivate->extra.isAllocated() || !childPrivate->extra->effectRefCount))
                continue;
            if (childPrivate->itemNode()->parent())
                childPrivate->itemNode()->parent()->removeChildNode(childPrivate->itemNode());

            itemPriv->childContainerNode()->appendChildNode(childPrivate->itemNode());
        }
    }

    if ((dirty & QQuickItemPrivate::Size) && itemPriv->clipNode()) {
        itemPriv->clipNode()->setRect(item->clipRect());
        itemPriv->clipNode()->update();
    }

    if (dirty & (QQuickItemPrivate::OpacityValue | QQuickItemPrivate::Visible
                 | QQuickItemPrivate::HideReference | QQuickItemPrivate::Window))
    {
        qreal opacity = itemPriv->explicitVisible && (!itemPriv->extra.isAllocated() || itemPriv->extra->hideRefCount == 0)
                      ? itemPriv->opacity() : qreal(0);

        if (opacity != 1 && !itemPriv->opacityNode()) {
            itemPriv->extra.value().opacityNode = new QSGOpacityNode;

            QSGNode *parent = itemPriv->itemNode();
            QSGNode *child = itemPriv->clipNode();
            if (!child)
                child = itemPriv->rootNode();
            if (!child)
                child = itemPriv->groupNode;

            if (child)
                parent->removeChildNode(child);
            parent->appendChildNode(itemPriv->opacityNode());
            if (child)
                itemPriv->opacityNode()->appendChildNode(child);
        }
        if (itemPriv->opacityNode())
            itemPriv->opacityNode()->setOpacity(opacity);
    }

    if (dirty & QQuickItemPrivate::ContentUpdateMask) {

        if (itemPriv->flags & QQuickItem::ItemHasContents) {
            updatePaintNodeData.transformNode = itemPriv->itemNode();
            itemPriv->paintNode = item->updatePaintNode(itemPriv->paintNode, &updatePaintNodeData);

            Q_ASSERT(itemPriv->paintNode == 0 ||
                     itemPriv->paintNode->parent() == 0 ||
                     itemPriv->paintNode->parent() == itemPriv->childContainerNode());

            if (itemPriv->paintNode && itemPriv->paintNode->parent() == 0) {
                if (itemPriv->extra.isAllocated() && itemPriv->extra->beforePaintNode)
                    itemPriv->childContainerNode()->insertChildNodeAfter(itemPriv->paintNode, itemPriv->extra->beforePaintNode);
                else
                    itemPriv->childContainerNode()->prependChildNode(itemPriv->paintNode);
            }
        } else if (itemPriv->paintNode) {
            delete itemPriv->paintNode;
            itemPriv->paintNode = 0;
        }
    }

#ifndef QT_NO_DEBUG
    // Check consistency.
    const QSGNode *nodeChain[] = {
        itemPriv->itemNodeInstance,
        itemPriv->opacityNode(),
        itemPriv->clipNode(),
        itemPriv->rootNode(),
        itemPriv->groupNode,
        itemPriv->paintNode,
    };

    int ip = 0;
    for (;;) {
        while (ip < 5 && nodeChain[ip] == 0)
            ++ip;
        if (ip == 5)
            break;
        int ic = ip + 1;
        while (ic < 5 && nodeChain[ic] == 0)
            ++ic;
        const QSGNode *parent = nodeChain[ip];
        const QSGNode *child = nodeChain[ic];
        if (child == 0) {
            Q_ASSERT(parent == itemPriv->groupNode || parent->childCount() == 0);
        } else {
            Q_ASSERT(parent == itemPriv->groupNode || parent->childCount() == 1);
            Q_ASSERT(child->parent() == parent);
            bool containsChild = false;
            for (QSGNode *n = parent->firstChild(); n; n = n->nextSibling())
                containsChild |= (n == child);
            Q_ASSERT(containsChild);
        }
        ip = ic;
    }
#endif

#ifdef QML_RUNTIME_TESTING
    if (itemPriv->sceneGraphContext()->isFlashModeEnabled()) {
        QSGFlashNode *flash = new QSGFlashNode();
        flash->setRect(item->boundingRect());
        itemPriv->childContainerNode()->appendChildNode(flash);
        didFlash = true;
    }
    Q_Q(QQuickWindow);
    if (didFlash) {
        q->maybeUpdate();
    }
#endif

}

void QQuickWindow::maybeUpdate()
{
    Q_D(QQuickWindow);
    d->windowManager->maybeUpdate(this);
}

void QQuickWindow::cleanupSceneGraph()
{
    Q_D(QQuickWindow);

    if (!d->renderer)
        return;

    delete d->renderer->rootNode();
    delete d->renderer;

    d->renderer = 0;
}

/*!
    Returns the opengl context used for rendering.

    If the scene graph is not ready, this function will return 0.

    \sa sceneGraphInitialized(), sceneGraphInvalidated()
 */

QOpenGLContext *QQuickWindow::openglContext() const
{
    Q_D(const QQuickWindow);
    if (d->context->isReady())
        return d->context->glContext();
    return 0;
}

/*!
    \fn void QQuickWindow::frameSwapped()

    This signal is emitted when the frame buffers have been swapped.

    This signal will be emitted from the scene graph rendering thread.
*/


/*!
    \fn void QQuickWindow::sceneGraphInitialized()

    This signal is emitted when the scene graph has been initialized.

    This signal will be emitted from the scene graph rendering thread.

 */


/*!
    \fn void QQuickWindow::sceneGraphInvalidated()

    This signal is emitted when the scene graph has been invalidated.

    This signal implies that the opengl rendering context used
    has been invalidated and all user resources tied to that context
    should be released.

    This signal will be emitted from the scene graph rendering thread.
 */


/*!
    Sets the render target for this window to be \a fbo.

    The specified fbo must be created in the context of the window
    or one that shares with it.

    \warning
    This function can only be called from the thread doing
    the rendering.
 */

void QQuickWindow::setRenderTarget(QOpenGLFramebufferObject *fbo)
{
    Q_D(QQuickWindow);
    if (d->context && QThread::currentThread() != d->context->thread()) {
        qWarning("QQuickWindow::setRenderThread: Cannot set render target from outside the rendering thread");
        return;
    }

    d->renderTarget = fbo;
    if (fbo) {
        d->renderTargetId = fbo->handle();
        d->renderTargetSize = fbo->size();
    } else {
        d->renderTargetId = 0;
        d->renderTargetSize = QSize();
    }
}

/*!
    \overload

    Sets the render target for this window to be an FBO with
    \a fboId and \a size.

    The specified FBO must be created in the context of the window
    or one that shares with it.

    \warning
    This function can only be called from the thread doing
    the rendering.
*/

void QQuickWindow::setRenderTarget(uint fboId, const QSize &size)
{
    Q_D(QQuickWindow);
    if (d->context && QThread::currentThread() != d->context->thread()) {
        qWarning("QQuickWindow::setRenderThread: Cannot set render target from outside the rendering thread");
        return;
    }

    d->renderTargetId = fboId;
    d->renderTargetSize = size;

    // Unset any previously set instance...
    d->renderTarget = 0;
}


/*!
    Returns the FBO id of the render target when set; otherwise returns 0.
 */
uint QQuickWindow::renderTargetId() const
{
    Q_D(const QQuickWindow);
    return d->renderTargetId;
}

/*!
    Returns the size of the currently set render target; otherwise returns an empty size.
 */
QSize QQuickWindow::renderTargetSize() const
{
    Q_D(const QQuickWindow);
    return d->renderTargetSize;
}




/*!
    Returns the render target for this window.

    The default is to render to the surface of the window, in which
    case the render target is 0.
 */
QOpenGLFramebufferObject *QQuickWindow::renderTarget() const
{
    Q_D(const QQuickWindow);
    return d->renderTarget;
}


/*!
    Grabs the contents of the window and returns it as an image.

    This function might not work if the window is not visible.

    \warning Calling this function will cause performance problems.

    \warning This function can only be called from the GUI thread.
 */
QImage QQuickWindow::grabWindow()
{
    Q_D(QQuickWindow);
    return d->windowManager->grab(this);
}

/*!
    Returns an incubation controller that splices incubation between frames
    for this window. QQuickView automatically installs this controller for you,
    otherwise you will need to install it yourself using \l{QQmlEngine::setIncubationController()}.

    The controller is owned by the window and will be destroyed when the window
    is deleted.
*/
QQmlIncubationController *QQuickWindow::incubationController() const
{
    Q_D(const QQuickWindow);

    if (!d->incubationController)
        d->incubationController = new QQuickWindowIncubationController(this);
    return d->incubationController;
}



/*!
    \enum QQuickWindow::CreateTextureOption

    The CreateTextureOption enums are used to customize a texture is wrapped.

    \value TextureHasAlphaChannel The texture has an alpha channel and should
    be drawn using blending.

    \value TextureHasMipmaps The texture has mipmaps and can be drawn with
    mipmapping enabled.

    \value TextureOwnsGLTexture The texture object owns the texture id and
    will delete the GL texture when the texture object is deleted.
 */

/*!
    \fn void QQuickWindow::beforeSynchronizing()

    This signal is emitted before the scene graph is synchronized with the QML state.

    This signal can be used to do any preparation required before calls to
    QQuickItem::updatePaintNode().

    The GL context used for rendering the scene graph will be bound at this point.

    \warning This signal is emitted from the scene graph rendering thread. If your
    slot function needs to finish before execution continues, you must make sure that
    the connection is direct (see Qt::ConnectionType).

    \warning Make very sure that a signal handler for beforeSynchronizing leaves the GL
    context in the same state as it was when the signal handler was entered. Failing to
    do so can result in the scene not rendering properly.
*/

/*!
    \fn void QQuickWindow::beforeRendering()

    This signal is emitted before the scene starts rendering.

    Combined with the modes for clearing the background, this option
    can be used to paint using raw GL under QML content.

    The GL context used for rendering the scene graph will be bound
    at this point.

    \warning This signal is emitted from the scene graph rendering thread. If your
    slot function needs to finish before execution continues, you must make sure that
    the connection is direct (see Qt::ConnectionType).

    \warning Make very sure that a signal handler for beforeRendering leaves the GL
    context in the same state as it was when the signal handler was entered. Failing to
    do so can result in the scene not rendering properly.
*/

/*!
    \fn void QQuickWindow::afterRendering()

    This signal is emitted after the scene has completed rendering, before swapbuffers is called.

    This signal can be used to paint using raw GL on top of QML content,
    or to do screen scraping of the current frame buffer.

    The GL context used for rendering the scene graph will be bound at this point.

    \warning This signal is emitted from the scene graph rendering thread. If your
    slot function needs to finish before execution continues, you must make sure that
    the connection is direct (see Qt::ConnectionType).

    \warning Make very sure that a signal handler for afterRendering() leaves the GL
    context in the same state as it was when the signal handler was entered. Failing to
    do so can result in the scene not rendering properly.
 */



/*!
    Sets whether the scene graph rendering of QML should clear the color buffer
    before it starts rendering to \a enabled.

    By disabling clearing of the color buffer, it is possible to do GL painting
    under the scene graph.

    The color buffer is cleared by default.

    \sa beforeRendering()
 */

void QQuickWindow::setClearBeforeRendering(bool enabled)
{
    Q_D(QQuickWindow);
    d->clearBeforeRendering = enabled;
}



/*!
    Returns whether clearing of the color buffer is done before rendering or not.
 */

bool QQuickWindow::clearBeforeRendering() const
{
    Q_D(const QQuickWindow);
    return d->clearBeforeRendering;
}



/*!
    Creates a new QSGTexture from the supplied \a image. If the image has an
    alpha channel, the corresponding texture will have an alpha channel.

    The caller of the function is responsible for deleting the returned texture.
    The actual GL texture will be deleted when the texture object is deleted.

    Depending on the underlying implementation of the scene graph, the returned
    texture may be part of an atlas. For code to be portable across implementations
    one should always use the texture coordinates returned from
    QSGTexture::normalizedTextureSubRect() when building geometry.

    \warning This function will return 0 if the scene graph has not yet been
    initialized.

    \warning The returned texture is not memory managed by the scene graph and
    must be explicitly deleted by the caller on the rendering thread.
    This is acheived by deleting the texture from a QSGNode destructor
    or by using deleteLater() in the case where the texture already has affinity
    to the rendering thread.

    This function can be called from any thread.

    \sa sceneGraphInitialized()
 */

QSGTexture *QQuickWindow::createTextureFromImage(const QImage &image) const
{
    Q_D(const QQuickWindow);
    if (d->context && d->context->isReady())
        return d->context->createTexture(image);
    else
        return 0;
}



/*!
    Creates a new QSGTexture object from an existing GL texture \a id and \a size.

    The caller of the function is responsible for deleting the returned texture.

    Use \a options to customize the texture attributes.

    \warning This function will return 0 if the scenegraph has not yet been
    initialized.

    \sa sceneGraphInitialized()
 */
QSGTexture *QQuickWindow::createTextureFromId(uint id, const QSize &size, CreateTextureOptions options) const
{
    Q_D(const QQuickWindow);
    if (d->context && d->context->isReady()) {
        QSGPlainTexture *texture = new QSGPlainTexture();
        texture->setTextureId(id);
        texture->setHasAlphaChannel(options & TextureHasAlphaChannel);
        texture->setHasMipmaps(options & TextureHasMipmaps);
        texture->setOwnsTexture(options & TextureOwnsGLTexture);
        texture->setTextureSize(size);
        return texture;
    }
    return 0;
}

/*!
    \qmlproperty color QtQuick.Window2::Window::color

    The background color for the window.

    Setting this property is more efficient than using a separate Rectangle.
*/

/*!
    \property QQuickWindow::color
    \brief The color used to clear the OpenGL context.

    Setting the clear color has no effect when clearing is disabled.
    By default, the clear color is white.

    \sa setClearBeforeRendering()
 */

void QQuickWindow::setColor(const QColor &color)
{
    Q_D(QQuickWindow);
    if (color == d->clearColor)
        return;

    d->clearColor = color;
    emit colorChanged(color);
    d->dirtyItem(contentItem());
}

QColor QQuickWindow::color() const
{
    return d_func()->clearColor;
}

/*!
    \qmlproperty string QtQuick.Window2::Window::title

    The window's title in the windowing system.

    The window title might appear in the title area of the window decorations,
    depending on the windowing system and the window flags. It might also
    be used by the windowing system to identify the window in other contexts,
    such as in the task switcher.
 */

/*!
    \qmlproperty string QtQuick.Window2::Window::modality

    The modality of the window.

    A modal window prevents other windows from receiving input events.
    Possible values are Qt.NonModal (the default), Qt.WindowModal,
    and Qt.ApplicationModal.
 */

#include "moc_qquickwindow.cpp"

QT_END_NAMESPACE
