QGLPixmapBlurFilter Class Reference

Inheritance diagram for QGLPixmapBlurFilter:

Public Functions
	QGLPixmapBlurFilter ()
Public Functions inherited from QGLCustomShaderStage
	QGLCustomShaderStage ()
void	removeFromPainter (QPainter *)
void	setInactive ()
bool	setOnPainter (QPainter *)
virtual void	setUniforms (QGLShaderProgram *)
void	setUniformsDirty ()
QByteArray	source () const
virtual	~QGLCustomShaderStage ()
Public Functions inherited from QGLPixmapFilter< QPixmapBlurFilter >
void	draw (QPainter *painter, const QPointF &pos, const QPixmap &src, const QRectF &srcRect=QRectF()) const
Public Functions inherited from QPixmapBlurFilter
QGraphicsBlurEffect::BlurHints	blurHints () const
	Gets the blur hints of the blur filter. More...
QRectF	boundingRectFor (const QRectF &rect) const
	QPixmapBlurFilter (QObject *parent=0)
	Constructs a pixmap blur filter. More...
qreal	radius () const
	Gets the radius of the blur filter. More...
void	setBlurHints (QGraphicsBlurEffect::BlurHints hints)
	Setting the blur hints to PerformanceHint causes the implementation to trade off visual quality to blur the image faster. More...
void	setRadius (qreal radius)
	Sets the radius of the blur filter. More...
	~QPixmapBlurFilter ()
	Destructor of pixmap blur filter. More...
Public Functions inherited from QPixmapFilter
FilterType	type () const
	Returns the type of the filter. More...
virtual	~QPixmapFilter ()=0
	Destroys the pixmap filter. More...
Public Functions inherited from QObject
bool	blockSignals (bool b)
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). More...
const QObjectList &	children () const
	Returns a list of child objects. More...
bool	connect (const QObject *sender, const char *signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const
bool	disconnect (const char *signal=0, const QObject *receiver=0, const char *member=0)
bool	disconnect (const QObject *receiver, const char *member=0)
void	dumpObjectInfo ()
	Dumps information about signal connections, etc. More...
void	dumpObjectTree ()
	Dumps a tree of children to the debug output. More...
QList< QByteArray >	dynamicPropertyNames () const
	Returns the names of all properties that were dynamically added to the object using setProperty(). More...
virtual bool	event (QEvent *)
	This virtual function receives events to an object and should return true if the event e was recognized and processed. More...
virtual bool	eventFilter (QObject *, QEvent *)
	Filters events if this object has been installed as an event filter for the watched object. More...
template<typename T >
T	findChild (const QString &aName=QString()) const
	Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. More...
template<typename T >
QList< T >	findChildren (const QString &aName=QString()) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. More...
template<typename T >
QList< T >	findChildren (const QRegExp &re) const
bool	inherits (const char *classname) const
	Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false. More...
void	installEventFilter (QObject *)
	Installs an event filter filterObj on this object. More...
bool	isWidgetType () const
	Returns true if the object is a widget; otherwise returns false. More...
void	killTimer (int id)
	Kills the timer with timer identifier, id. More...
virtual const QMetaObject *	metaObject () const
	Returns a pointer to the meta-object of this object. More...
void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children. More...
QString	objectName () const
QObject *	parent () const
	Returns a pointer to the parent object. More...
QVariant	property (const char *name) const
	Returns the value of the object's name property. More...
Q_INVOKABLE	QObject (QObject *parent=0)
	Constructs an object with parent object parent. More...
void	removeEventFilter (QObject *)
	Removes an event filter object obj from this object. More...
void	setObjectName (const QString &name)
void	setParent (QObject *)
	Makes the object a child of parent. More...
bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value. More...
void	setUserData (uint id, QObjectUserData *data)
bool	signalsBlocked () const
	Returns true if signals are blocked; otherwise returns false. More...
int	startTimer (int interval)
	Starts a timer and returns a timer identifier, or returns zero if it could not start a timer. More...
QThread *	thread () const
	Returns the thread in which the object lives. More...
QObjectUserData *	userData (uint id) const
virtual	~QObject ()
	Destroys the object, deleting all its child objects. More...
Public Functions inherited from QGLPixmapFilterBase
virtual	~QGLPixmapFilterBase ()

Protected Functions
bool	processGL (QPainter *painter, const QPointF &pos, const QPixmap &src, const QRectF &srcRect) const
Protected Functions inherited from QGLCustomShaderStage
void	setSource (const QByteArray &)
Protected Functions inherited from QPixmapFilter
	QPixmapFilter (QPixmapFilterPrivate &d, FilterType type, QObject *parent)
	QPixmapFilter (FilterType type, QObject *parent)
	Constructs a default QPixmapFilter with the given type. More...
Protected Functions inherited from QObject
virtual void	childEvent (QChildEvent *)
	This event handler can be reimplemented in a subclass to receive child events. More...
virtual void	connectNotify (const char *signal)
	This virtual function is called when something has been connected to signal in this object. More...
virtual void	customEvent (QEvent *)
	This event handler can be reimplemented in a subclass to receive custom events. More...
virtual void	disconnectNotify (const char *signal)
	This virtual function is called when something has been disconnected from signal in this object. More...
	QObject (QObjectPrivate &dd, QObject *parent=0)
int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal. More...
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0. More...
int	senderSignalIndex () const
virtual void	timerEvent (QTimerEvent *)
	This event handler can be reimplemented in a subclass to receive timer events for the object. More...
Protected Functions inherited from QGLPixmapFilterBase
void	bindTexture (const QPixmap &src) const
void	drawImpl (QPainter *painter, const QPointF &pos, const QPixmap &src, const QRectF &srcRect=QRectF()) const

Additional Inherited Members
Public Types inherited from QPixmapFilter
enum	FilterType {   ConvolutionFilter, ColorizeFilter, DropShadowFilter, BlurFilter,   UserFilter = 1024 }
	This enum describes the types of filter that can be applied to pixmaps. More...
Public Slots inherited from QObject
void	deleteLater ()
	Schedules this object for deletion. More...
Signals inherited from QObject
void	destroyed (QObject *=0)
	This signal is emitted immediately before the object obj is destroyed, and can not be blocked. More...
Static Public Functions inherited from QObject
static bool	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *member, Qt::ConnectionType=Qt::AutoConnection)
	Creates a connection of the given type from the signal in the sender object to the method in the receiver object. More...
static bool	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)
static bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *member)
	Disconnects signal in object sender from method in object receiver. More...
static bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &member)
static uint	registerUserData ()
static QString	tr (const char *sourceText, const char *comment=0, int n=-1)
static QString	trUtf8 (const char *sourceText, const char *comment=0, int n=-1)
Static Public Variables inherited from QObject
static const QMetaObject	staticMetaObject
	This variable stores the meta-object for the class. More...
Protected Variables inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Static Protected Variables inherited from QObject
static const QMetaObject	staticQtMetaObject
Related Functions inherited from QObject
T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QRegExp &regExp)()
T *	qobject_cast (QObject *object)
	QObjectList
void *	qt_find_obj_child (QObject *parent, const char *type, const QString &name)
	Returns a pointer to the object named name that inherits type and with a given parent. More...

Detailed Description

Definition at line 108 of file qglpixmapfilter.cpp.

Constructors and Destructors

QGLPixmapBlurFilter()

QGLPixmapBlurFilter::QGLPixmapBlurFilter

(

)

Definition at line 276 of file qglpixmapfilter.cpp.

{
}

Functions

processGL()

bool QGLPixmapBlurFilter::processGL ( QPainter *  painter, const QPointF &  pos, const QPixmap &  src, const QRectF &  srcRect  ) const

protectedvirtual

Implements QGLPixmapFilterBase.

Definition at line 431 of file qglpixmapfilter.cpp.

{
    if (radius() < 1) {
        painter->drawPixmap(pos, src);
        return true;
    }

    qreal actualRadius = radius();

    QGLContext *ctx = const_cast<QGLContext *>(QGLContext::currentContext());

    QGLBlurTextureCache *blurTextureCache = QGLBlurTextureCache::cacheForContext(ctx);
    QGLBlurTextureInfo *info = 0;
    int padding = nextMultiple(qCeil(actualRadius), qAnimatedBlurLevelIncrement);
    QRect targetRect = src.rect().adjusted(-padding, -padding, padding, padding);

    // pad so that we'll be able to half-scale qMaxBlurHalfScaleLevel times
    targetRect.setWidth((targetRect.width() + (qMaxBlurHalfScaleLevel-1)) & ~(qMaxBlurHalfScaleLevel-1));
    targetRect.setHeight((targetRect.height() + (qMaxBlurHalfScaleLevel-1)) & ~(qMaxBlurHalfScaleLevel-1));

    QSize textureSize;

    info = blurTextureCache->takeBlurTextureInfo(src);
    if (!info || info->radius() < actualRadius) {
        QSize paddedSize = targetRect.size() / 2;

        QImage padded(paddedSize.height(), paddedSize.width(), QImage::Format_ARGB32_Premultiplied);
        padded.fill(0);

        if (info) {
            int oldPadding = qRound(info->radius());

            QPainter p(&padded);
            p.setCompositionMode(QPainter::CompositionMode_Source);
            p.drawImage((padding - oldPadding) / 2, (padding - oldPadding) / 2, info->paddedImage());
            p.end();
        } else {
            // TODO: combine byteswapping and memrotating into one by declaring
            // custom GL_RGBA pixel type and qt_colorConvert template for it
            QImage prepadded = qt_halfScaled(src.toImage()).convertToFormat(QImage::Format_ARGB32_Premultiplied);

            // byte-swap and memrotates in one go
            qt_memrotate90_gl(reinterpret_cast<const quint32*>(prepadded.bits()),
                              prepadded.width(), prepadded.height(), prepadded.bytesPerLine(),
                              reinterpret_cast<quint32*>(padded.scanLine(padding / 2)) + padding / 2,
                              padded.bytesPerLine());
        }

        delete info;
        info = new QGLBlurTextureInfo(padded, generateBlurTexture(paddedSize), padding);

        textureSize = paddedSize;
    } else {
        textureSize = QSize(info->paddedImage().height(), info->paddedImage().width());
    }

    actualRadius *= qreal(0.5);
    int level = 1;
    for (; level < qMaxBlurHalfScaleLevel; ++level) {
        if (actualRadius <= 16)
            break;
        actualRadius *= qreal(0.5);
    }

    const int s = (1 << level);

    int prepadding = qRound(info->radius());
    padding = qMin(prepadding, qCeil(actualRadius) << level);
    targetRect = src.rect().adjusted(-padding, -padding, padding, padding);

    targetRect.setWidth(targetRect.width() & ~(s-1));
    targetRect.setHeight(targetRect.height() & ~(s-1));

    int paddingDelta = (prepadding - padding) >> level;

    QRect subRect(paddingDelta, paddingDelta, targetRect.width() >> level, targetRect.height() >> level);
    QImage sourceImage = info->paddedImage(level-1);

    QImage subImage(subRect.height(), subRect.width(), QImage::Format_ARGB32_Premultiplied);
    qt_rectcopy((QRgb *)subImage.bits(), ((QRgb *)sourceImage.scanLine(paddingDelta)) + paddingDelta,
                0, 0, subRect.height(), subRect.width(), subImage.bytesPerLine(), sourceImage.bytesPerLine());

    GLuint texture = info->texture();

    qt_blurImage(subImage, actualRadius, blurHints() & QGraphicsBlurEffect::QualityHint, 1);

    // subtract one pixel off the end to prevent the bilinear sampling from sampling uninitialized data
    QRect textureSubRect = subImage.rect().adjusted(0, 0, -1, -1);
    QRectF targetRectF = QRectF(targetRect).adjusted(0, 0, -targetRect.width() / qreal(textureSize.width()), -targetRect.height() / qreal(textureSize.height()));

    glBindTexture(GL_TEXTURE_2D, texture);
    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, subImage.width(), subImage.height(), GL_RGBA,
            GL_UNSIGNED_BYTE, const_cast<const QImage &>(subImage).bits());

    QGL2PaintEngineEx *engine = static_cast<QGL2PaintEngineEx *>(painter->paintEngine());
    painter->setRenderHint(QPainter::SmoothPixmapTransform);

    // texture is flipped on the y-axis
    targetRectF = QRectF(targetRectF.x(), targetRectF.bottom(), targetRectF.width(), -targetRectF.height());
    engine->drawTexture(targetRectF.translated(pos), texture, textureSize, textureSubRect);

    blurTextureCache->insertBlurTextureInfo(src, info);

    return true;
}

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The documentation for this class was generated from the following file:

• /src/opengl/qglpixmapfilter.cpp