qpaintengine_alpha_p.h

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#ifndef QPAINTENGINE_ALPHA_P_H
#define QPAINTENGINE_ALPHA_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.
//

#ifndef QT_NO_PRINTER
#include "private/qpaintengine_p.h"

QT_BEGIN_NAMESPACE

class QAlphaPaintEnginePrivate;

class QAlphaPaintEngine : public QPaintEngine
{
    Q_DECLARE_PRIVATE(QAlphaPaintEngine)
public:
    ~QAlphaPaintEngine();

    virtual bool begin(QPaintDevice *pdev);
    virtual bool end();

    virtual void updateState(const QPaintEngineState &state);

    virtual void drawPath(const QPainterPath &path);

    virtual void drawPolygon(const QPointF *points, int pointCount, PolygonDrawMode mode);

    virtual void drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr);
    virtual void drawImage(const QRectF &r, const QImage &image, const QRectF &sr);
    virtual void drawTextItem(const QPointF &p, const QTextItem &textItem);
    virtual void drawTiledPixmap(const QRectF &r, const QPixmap &pixmap, const QPointF &s);

protected:
    QAlphaPaintEngine(QAlphaPaintEnginePrivate &data, PaintEngineFeatures devcaps = 0);
    QRegion alphaClipping() const;
    bool continueCall() const;
    void flushAndInit(bool init = true);
    void cleanUp();
};

class QAlphaPaintEnginePrivate : public QPaintEnginePrivate
{
    Q_DECLARE_PUBLIC(QAlphaPaintEngine)
public:
    QAlphaPaintEnginePrivate();
    ~QAlphaPaintEnginePrivate();

    int m_pass;
    QPicture *m_pic;
    QPaintEngine *m_picengine;
    QPainter *m_picpainter;

    QPaintEngine::PaintEngineFeatures m_savedcaps;
    QPaintDevice *m_pdev;

    QRegion m_alphargn;
    QRegion m_cliprgn;

    bool m_hasalpha;
    bool m_alphaPen;
    bool m_alphaBrush;
    bool m_alphaOpacity;
    bool m_advancedPen;
    bool m_advancedBrush;
    bool m_complexTransform;
    bool m_emulateProjectiveTransforms;
    bool m_continueCall;

    QTransform m_transform;
    QPen m_pen;

    void addAlphaRect(const QRectF &rect);
    QRectF addPenWidth(const QPainterPath &path);
    void drawAlphaImage(const QRectF &rect);
    QRect toRect(const QRectF &rect) const;
    bool fullyContained(const QRectF &rect) const;

    void resetState(QPainter *p);
};

QT_END_NAMESPACE

#endif // QT_NO_PRINTER

#endif // QPAINTENGINE_ALPHA_P_H