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#ifndef QGRAPHICSSCENEBSPTREEINDEX_P_H
#define QGRAPHICSSCENEBSPTREEINDEX_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of qapplication_*.cpp, qwidget*.cpp and qfiledialog.cpp.  This header
// file may change from version to version without notice, or even be removed.
//
// We mean it.
//

#include "qgraphicsscenebsptreeindex.h"

#if !defined(QT_NO_GRAPHICSVIEW) || (QT_EDITION & QT_MODULE_GRAPHICSVIEW) != QT_MODULE_GRAPHICSVIEW

#include <private/qgraphicssceneindex_p.h>
#include <private/qgraphicsitem_p.h>

QT_BEGIN_NAMESPACE

static const int QGRAPHICSSCENE_INDEXTIMER_TIMEOUT = 2000;

class QGraphicsScene;

class QGraphicsSceneBspTreeIndexPrivate : public QGraphicsSceneIndexPrivate
{
    Q_DECLARE_PUBLIC(QGraphicsSceneBspTreeIndex)
public:
    QGraphicsSceneBspTreeIndexPrivate(QGraphicsScene *scene);

    QGraphicsSceneBspTree bsp;
    QRectF sceneRect;
    int bspTreeDepth;
    int indexTimerId;
    bool restartIndexTimer;
    bool regenerateIndex;
    int lastItemCount;

    QList<QGraphicsItem *> indexedItems;
    QList<QGraphicsItem *> unindexedItems;
    QList<int> freeItemIndexes;

    bool purgePending;
    QSet<QGraphicsItem *> removedItems;
    void purgeRemovedItems();

    void _q_updateIndex();
    void startIndexTimer(int interval = QGRAPHICSSCENE_INDEXTIMER_TIMEOUT);
    void resetIndex();

    void addToIndex(QGraphicsItem *item);
    void removeFromIndex(QGraphicsItem *item);

    void _q_updateSortCache();
    bool sortCacheEnabled;
    bool updatingSortCache;
    void invalidateSortCache();

    static void climbTree(QGraphicsItem *item, int *stackingOrder);
    static bool closestItemFirst_withoutCache(const QGraphicsItem *item1, const QGraphicsItem *item2);
    static bool closestItemLast_withoutCache(const QGraphicsItem *item1, const QGraphicsItem *item2);

    static inline bool closestItemFirst_withCache(const QGraphicsItem *item1, const QGraphicsItem *item2)
    {
        return item1->d_ptr->globalStackingOrder < item2->d_ptr->globalStackingOrder;
    }
    static inline bool closestItemLast_withCache(const QGraphicsItem *item1, const QGraphicsItem *item2)
    {
        return item1->d_ptr->globalStackingOrder >= item2->d_ptr->globalStackingOrder;
    }

    static void sortItems(QList<QGraphicsItem *> *itemList, Qt::SortOrder order, bool cached);
};


/*!
    \internal
*/
inline bool qt_closestLeaf(const QGraphicsItem *item1, const QGraphicsItem *item2)
{
    // Return true if sibling item1 is on top of item2.
    const QGraphicsItemPrivate *d1 = item1->d_ptr;
    const QGraphicsItemPrivate *d2 = item2->d_ptr;
    bool f1 = d1->flags & QGraphicsItem::ItemStacksBehindParent;
    bool f2 = d2->flags & QGraphicsItem::ItemStacksBehindParent;
    if (f1 != f2) return f2;
    qreal z1 = d1->z;
    qreal z2 = d2->z;
    return z1 > z2;
}

/*!
    \internal
*/
static inline bool qt_notclosestLeaf(const QGraphicsItem *item1, const QGraphicsItem *item2)
{
    return qt_closestLeaf(item2, item1);
}


QT_END_NAMESPACE

#endif // QGRAPHICSSCENEBSPTREEINDEX_P_H

#endif