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#ifndef QTEXTUREGLYPHCACHE_P_H

#define QTEXTUREGLYPHCACHE_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists for the convenience

// of other Qt classes.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include <QtGui/private/qtguiglobal_p.h>

#include <qhash.h>

#include <qimage.h>

#include <qobject.h>

#include <qtransform.h>

#include <private/qfontengineglyphcache_p.h>

#ifndef QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH

#define QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH 256

#endif

struct glyph_metrics_t;

typedef unsigned int glyph_t;

QT_BEGIN_NAMESPACE

class QTextItemInt;

class Q_GUI_EXPORT QTextureGlyphCache : public QFontEngineGlyphCache

{

public:

    QTextureGlyphCache(QFontEngine::GlyphFormat format, const QTransform &matrix, const QColor &color = QColor())

        : QFontEngineGlyphCache(format, matrix, color), m_current_fontengine(nullptr),

                                               m_w(0), m_h(0), m_cx(0), m_cy(0), m_currentRowHeight(0)

        { }

    ~QTextureGlyphCache();

    struct GlyphAndSubPixelPosition

    {

        GlyphAndSubPixelPosition(glyph_t g, QFixed spp) : glyph(g), subPixelPosition(spp) {}

        bool operator==(const GlyphAndSubPixelPosition &other) const

        {

            return glyph == other.glyph && subPixelPosition == other.subPixelPosition;

        }

        glyph_t glyph;

        QFixed subPixelPosition;

    };

    struct Coord {

        int x;

        int y;

        int w;

        int h;

        int baseLineX;

        int baseLineY;

        bool isNull() const

        {

            return w == 0 || h == 0;

        }

    };

    bool populate(QFontEngine *fontEngine, int numGlyphs, const glyph_t *glyphs,

                  const QFixedPoint *positions, bool includeGlyphCacheScale = false);

    bool hasPendingGlyphs() const { return !m_pendingGlyphs.isEmpty(); };

    void fillInPendingGlyphs();

    virtual void createTextureData(int width, int height) = 0;

    virtual void resizeTextureData(int width, int height) = 0;

    virtual int glyphPadding() const { return 0; }

    virtual void beginFillTexture() { }

    virtual void fillTexture(const Coord &coord, glyph_t glyph, QFixed subPixelPosition) = 0;

    virtual void endFillTexture() { }

    inline void createCache(int width, int height) {

        m_w = width;

        m_h = height;

        createTextureData(width, height);

    }

    inline void resizeCache(int width, int height)

    {

        resizeTextureData(width, height);

        m_w = width;

        m_h = height;

    }

    inline bool isNull() const { return m_h == 0; }

    QHash<GlyphAndSubPixelPosition, Coord> coords;

    virtual int maxTextureWidth() const { return QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH; }

    virtual int maxTextureHeight() const { return -1; }

    QImage textureMapForGlyph(glyph_t g, QFixed subPixelPosition) const;

protected:

    int calculateSubPixelPositionCount(glyph_t) const;

    QFontEngine *m_current_fontengine;

    QHash<GlyphAndSubPixelPosition, Coord> m_pendingGlyphs;

    int m_w; // image width

    int m_h; // image height

    int m_cx; // current x

    int m_cy; // current y

    int m_currentRowHeight; // Height of last row

};

inline uint qHash(const QTextureGlyphCache::GlyphAndSubPixelPosition &g)

{

    return (g.glyph << 8)  | (g.subPixelPosition * 10).round().toInt();

}

class Q_GUI_EXPORT QImageTextureGlyphCache : public QTextureGlyphCache

{

public:

    QImageTextureGlyphCache(QFontEngine::GlyphFormat format, const QTransform &matrix, const QColor &color = QColor())

        : QTextureGlyphCache(format, matrix, color) { }

    ~QImageTextureGlyphCache();

    virtual void createTextureData(int width, int height) override;

    virtual void resizeTextureData(int width, int height) override;

    virtual void fillTexture(const Coord &c, glyph_t glyph, QFixed subPixelPosition) override;

    inline const QImage &image() const { return m_image; }

private:

    QImage m_image;

};

QT_END_NAMESPACE

#endif