qgeotilecache_p.h

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#ifndef QGEOTILECACHE_P_H
#define QGEOTILECACHE_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtLocation/qlocationglobal.h>

#include <QObject>
#include <QCache>
#include "qcache3q_p.h"
#include <QSet>
#include <QMutex>
#include <QTimer>

#include "qgeotilespec_p.h"
#include "qgeotiledmappingmanagerengine_p.h"

#include <QImage>

QT_BEGIN_NAMESPACE

class QGeoMappingManager;

class QGeoTile;
class QGeoCachedTileMemory;
class QGeoTileCache;

class QPixmap;
class QThread;

/* This would be internal to qgeotilecache.cpp except that the eviction
 * policy can't be defined without it being concrete here */
class QGeoCachedTileDisk
{
public:
    ~QGeoCachedTileDisk();

    QGeoTileSpec spec;
    QString filename;
    QString format;
    QGeoTileCache *cache;
};

/* This is also used in the mapgeometry */
class Q_LOCATION_EXPORT QGeoTileTexture
{
public:

    QGeoTileTexture();
    ~QGeoTileTexture();

    QGeoTileSpec spec;
    QImage image;
    bool textureBound;
};

/* Custom eviction policy for the disk cache, to avoid deleting all the files
 * when the application closes */
class QCache3QTileEvictionPolicy : public QCache3QDefaultEvictionPolicy<QGeoTileSpec,QGeoCachedTileDisk>
{
protected:
    void aboutToBeRemoved(const QGeoTileSpec &key, QSharedPointer<QGeoCachedTileDisk> obj);
    void aboutToBeEvicted(const QGeoTileSpec &key, QSharedPointer<QGeoCachedTileDisk> obj);
};

class Q_LOCATION_EXPORT QGeoTileCache : public QObject
{
    Q_OBJECT
public:
    QGeoTileCache(const QString &directory = QString(), QObject *parent = 0);
    ~QGeoTileCache();

    void setMaxDiskUsage(int diskUsage);
    int maxDiskUsage() const;
    int diskUsage() const;

    void setMaxMemoryUsage(int memoryUsage);
    int maxMemoryUsage() const;
    int memoryUsage() const;

    void setMinTextureUsage(int textureUsage);
    void setExtraTextureUsage(int textureUsage);
    int maxTextureUsage() const;
    int minTextureUsage() const;
    int textureUsage() const;

    QSharedPointer<QGeoTileTexture> get(const QGeoTileSpec &spec);
    QString directory() const;

    // can be called without a specific tileCache pointer
    static void evictFromDiskCache(QGeoCachedTileDisk *td);
    static void evictFromMemoryCache(QGeoCachedTileMemory *tm);

    void insert(const QGeoTileSpec &spec,
                const QByteArray &bytes,
                const QString &format,
                QGeoTiledMappingManagerEngine::CacheAreas areas = QGeoTiledMappingManagerEngine::AllCaches);
    void handleError(const QGeoTileSpec &spec, const QString &errorString);

public Q_SLOTS:
    void printStats();

private:
    void loadTiles();

    QSharedPointer<QGeoCachedTileDisk> addToDiskCache(const QGeoTileSpec &spec, const QString &filename);
    QSharedPointer<QGeoCachedTileMemory> addToMemoryCache(const QGeoTileSpec &spec, const QByteArray &bytes, const QString &format);
    QSharedPointer<QGeoTileTexture> addToTextureCache(const QGeoTileSpec &spec, const QPixmap &pixmap);

    static QString tileSpecToFilename(const QGeoTileSpec &spec, const QString &format, const QString &directory);
    static QGeoTileSpec filenameToTileSpec(const QString &filename);

    QString directory_;
    QCache3Q<QGeoTileSpec, QGeoCachedTileDisk, QCache3QTileEvictionPolicy > diskCache_;
    QCache3Q<QGeoTileSpec, QGeoCachedTileMemory > memoryCache_;
    QCache3Q<QGeoTileSpec, QGeoTileTexture > textureCache_;

    int minTextureUsage_;
    int extraTextureUsage_;
};

QT_END_NAMESPACE

#endif // QGEOTILECACHE_P_H