qgraphicseffect.h

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#ifndef QGRAPHICSEFFECT_H
#define QGRAPHICSEFFECT_H
 
#include <QtWidgets/qtwidgetsglobal.h>
#include <QtCore/qobject.h>
#include <QtCore/qpoint.h>
#include <QtCore/qrect.h>
#include <QtGui/qcolor.h>
#include <QtGui/qbrush.h>
 
QT_REQUIRE_CONFIG(graphicseffect);
 
QT_BEGIN_NAMESPACE
 
class QGraphicsItem;
class QStyleOption;
class QPainter;
class QPixmap;
 
class QGraphicsEffectSource;
 
class QGraphicsEffectPrivate;
class Q_WIDGETS_EXPORT QGraphicsEffect : public QObject
{
    Q_OBJECT
    Q_PROPERTY(bool enabled READ isEnabled WRITE setEnabled NOTIFY enabledChanged)
public:
    enum ChangeFlag {
        SourceAttached = 0x1,
        SourceDetached = 0x2,
        SourceBoundingRectChanged = 0x4,
        SourceInvalidated = 0x8
    };
    Q_DECLARE_FLAGS(ChangeFlags, ChangeFlag)
    Q_FLAG(ChangeFlags)
 
    enum PixmapPadMode {
        NoPad,
        PadToTransparentBorder,
        PadToEffectiveBoundingRect
    };
 
    QGraphicsEffect(QObject *parent = nullptr);
    virtual ~QGraphicsEffect();
 
    virtual QRectF boundingRectFor(const QRectF &sourceRect) const;
    QRectF boundingRect() const;
 
    bool isEnabled() const;
 
public Q_SLOTS:
    void setEnabled(bool enable);
    void update();
 
Q_SIGNALS:
    void enabledChanged(bool enabled);
 
protected:
    QGraphicsEffect(QGraphicsEffectPrivate &d, QObject *parent = nullptr);
    virtual void draw(QPainter *painter) = 0;
    virtual void sourceChanged(ChangeFlags flags);
    void updateBoundingRect();
 
    bool sourceIsPixmap() const;
    QRectF sourceBoundingRect(Qt::CoordinateSystem system = Qt::LogicalCoordinates) const;
    void drawSource(QPainter *painter);
    QPixmap sourcePixmap(Qt::CoordinateSystem system = Qt::LogicalCoordinates,
                         QPoint *offset = nullptr,
                         PixmapPadMode mode = PadToEffectiveBoundingRect) const;
 
private:
    Q_DECLARE_PRIVATE(QGraphicsEffect)
    Q_DISABLE_COPY(QGraphicsEffect)
    friend class QGraphicsItem;
    friend class QGraphicsItemPrivate;
    friend class QGraphicsScenePrivate;
    friend class QWidget;
    friend class QWidgetPrivate;
 
public:
    QGraphicsEffectSource *source() const; // internal
 
};
Q_DECLARE_OPERATORS_FOR_FLAGS(QGraphicsEffect::ChangeFlags)
 
class QGraphicsColorizeEffectPrivate;
class Q_WIDGETS_EXPORT QGraphicsColorizeEffect: public QGraphicsEffect
{
    Q_OBJECT
    Q_PROPERTY(QColor color READ color WRITE setColor NOTIFY colorChanged)
    Q_PROPERTY(qreal strength READ strength WRITE setStrength NOTIFY strengthChanged)
public:
    QGraphicsColorizeEffect(QObject *parent = nullptr);
    ~QGraphicsColorizeEffect();
 
    QColor color() const;
    qreal strength() const;
 
public Q_SLOTS:
    void setColor(const QColor &c);
    void setStrength(qreal strength);
 
Q_SIGNALS:
    void colorChanged(const QColor &color);
    void strengthChanged(qreal strength);
 
protected:
    void draw(QPainter *painter) override;
 
private:
    Q_DECLARE_PRIVATE(QGraphicsColorizeEffect)
    Q_DISABLE_COPY(QGraphicsColorizeEffect)
};
 
class QGraphicsBlurEffectPrivate;
class Q_WIDGETS_EXPORT QGraphicsBlurEffect: public QGraphicsEffect
{
    Q_OBJECT
    Q_PROPERTY(qreal blurRadius READ blurRadius WRITE setBlurRadius NOTIFY blurRadiusChanged)
    Q_PROPERTY(BlurHints blurHints READ blurHints WRITE setBlurHints NOTIFY blurHintsChanged)
public:
    enum BlurHint {
        PerformanceHint = 0x00,
        QualityHint = 0x01,
        AnimationHint = 0x02
    };
    Q_ENUM(BlurHint)
    Q_DECLARE_FLAGS(BlurHints, BlurHint)
    Q_FLAG(BlurHints)
 
    QGraphicsBlurEffect(QObject *parent = nullptr);
    ~QGraphicsBlurEffect();
 
    QRectF boundingRectFor(const QRectF &rect) const override;
    qreal blurRadius() const;
    BlurHints blurHints() const;
 
public Q_SLOTS:
    void setBlurRadius(qreal blurRadius);
    void setBlurHints(BlurHints hints);
 
Q_SIGNALS:
    void blurRadiusChanged(qreal blurRadius);
    void blurHintsChanged(BlurHints hints);
 
protected:
    void draw(QPainter *painter) override;
 
private:
    Q_DECLARE_PRIVATE(QGraphicsBlurEffect)
    Q_DISABLE_COPY(QGraphicsBlurEffect)
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS(QGraphicsBlurEffect::BlurHints)
 
class QGraphicsDropShadowEffectPrivate;
class Q_WIDGETS_EXPORT QGraphicsDropShadowEffect: public QGraphicsEffect
{
    Q_OBJECT
    Q_PROPERTY(QPointF offset READ offset WRITE setOffset NOTIFY offsetChanged)
    Q_PROPERTY(qreal xOffset READ xOffset WRITE setXOffset NOTIFY offsetChanged)
    Q_PROPERTY(qreal yOffset READ yOffset WRITE setYOffset NOTIFY offsetChanged)
    Q_PROPERTY(qreal blurRadius READ blurRadius WRITE setBlurRadius NOTIFY blurRadiusChanged)
    Q_PROPERTY(QColor color READ color WRITE setColor NOTIFY colorChanged)
public:
    QGraphicsDropShadowEffect(QObject *parent = nullptr);
    ~QGraphicsDropShadowEffect();
 
    QRectF boundingRectFor(const QRectF &rect) const override;
    QPointF offset() const;
 
    inline qreal xOffset() const
    { return offset().x(); }
 
    inline qreal yOffset() const
    { return offset().y(); }
 
    qreal blurRadius() const;
    QColor color() const;
 
public Q_SLOTS:
    void setOffset(const QPointF &ofs);
 
    inline void setOffset(qreal dx, qreal dy)
    { setOffset(QPointF(dx, dy)); }
 
    inline void setOffset(qreal d)
    { setOffset(QPointF(d, d)); }
 
    inline void setXOffset(qreal dx)
    { setOffset(QPointF(dx, yOffset())); }
 
    inline void setYOffset(qreal dy)
    { setOffset(QPointF(xOffset(), dy)); }
 
    void setBlurRadius(qreal blurRadius);
    void setColor(const QColor &color);
 
Q_SIGNALS:
    void offsetChanged(const QPointF &offset);
    void blurRadiusChanged(qreal blurRadius);
    void colorChanged(const QColor &color);
 
protected:
    void draw(QPainter *painter) override;
 
private:
    Q_DECLARE_PRIVATE(QGraphicsDropShadowEffect)
    Q_DISABLE_COPY(QGraphicsDropShadowEffect)
};
 
class QGraphicsOpacityEffectPrivate;
class Q_WIDGETS_EXPORT QGraphicsOpacityEffect: public QGraphicsEffect
{
    Q_OBJECT
    Q_PROPERTY(qreal opacity READ opacity WRITE setOpacity NOTIFY opacityChanged)
    Q_PROPERTY(QBrush opacityMask READ opacityMask WRITE setOpacityMask NOTIFY opacityMaskChanged)
public:
    QGraphicsOpacityEffect(QObject *parent = nullptr);
    ~QGraphicsOpacityEffect();
 
    qreal opacity() const;
    QBrush opacityMask() const;
 
public Q_SLOTS:
    void setOpacity(qreal opacity);
    void setOpacityMask(const QBrush &mask);
 
Q_SIGNALS:
    void opacityChanged(qreal opacity);
    void opacityMaskChanged(const QBrush &mask);
 
protected:
    void draw(QPainter *painter) override;
 
private:
    Q_DECLARE_PRIVATE(QGraphicsOpacityEffect)
    Q_DISABLE_COPY(QGraphicsOpacityEffect)
};
 
QT_END_NAMESPACE
 
#endif // QGRAPHICSEFFECT_H