QGraphicsEffectSource Class Reference

The QGraphicsEffectSource class represents the source on which a QGraphicsEffect is installed on. More...

#include <qgraphicseffect_p.h>

Inheritance diagram for QGraphicsEffectSource:

Public Functions
QRectF	boundingRect (Qt::CoordinateSystem coordinateSystem=Qt::LogicalCoordinates) const
	Returns the bounding rectangle of the source mapped to the given system. More...
QRect	deviceRect () const
void	draw (QPainter *painter)
	Draws the source using the given painter. More...
const QGraphicsItem *	graphicsItem () const
	Returns a pointer to the item if this source is a QGraphicsItem; otherwise returns 0. More...
bool	isPixmap () const
	Returns true if the source effectively is a pixmap, e.g., a QGraphicsPixmapItem. More...
QPixmap	pixmap (Qt::CoordinateSystem system=Qt::LogicalCoordinates, QPoint *offset=0, QGraphicsEffect::PixmapPadMode mode=QGraphicsEffect::PadToEffectiveBoundingRect) const
	Returns a pixmap with the source painted into it. More...
const QStyleOption *	styleOption () const
	Returns a pointer to the style options (used when drawing the source) if available; otherwise returns 0. More...
void	update ()
	Schedules a redraw of the source. More...
const QWidget *	widget () const
	Returns a pointer to the widget if this source is a QWidget; otherwise returns 0. More...
	~QGraphicsEffectSource ()
	Destroys the effect source. 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...

Protected Functions
	QGraphicsEffectSource (QGraphicsEffectSourcePrivate &dd, QObject *parent=0)
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...

Friends
class	QGraphicsEffect
class	QGraphicsEffectPrivate
class	QGraphicsItem
class	QGraphicsItemPrivate
class	QGraphicsScenePrivate
class	QWidget
class	QWidgetPrivate

Additional Inherited Members
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

The QGraphicsEffectSource class represents the source on which a QGraphicsEffect is installed on.

Warning

This function is not part of the public interface.

When a QGraphicsEffect is installed on a QGraphicsItem, for example, this class will act as a wrapper around QGraphicsItem. Then, calling update() is effectively the same as calling QGraphicsItem::update().

QGraphicsEffectSource also provides a pixmap() function which creates a pixmap with the source painted into it.

See also

QGraphicsItem::setGraphicsEffect(), QWidget::setGraphicsEffect().

Definition at line 67 of file qgraphicseffect_p.h.

Constructors and Destructors

~QGraphicsEffectSource()

QGraphicsEffectSource::~QGraphicsEffectSource

(

)

Destroys the effect source.

Definition at line 153 of file qgraphicseffect.cpp.

{}

QGraphicsEffectSource()

QGraphicsEffectSource::QGraphicsEffectSource ( QGraphicsEffectSourcePrivate &  dd, QObject *  parent = 0  )

protected

Warning

This function is not part of the public interface.

Definition at line 146 of file qgraphicseffect.cpp.

    : QObject(dd, parent)
{}

Functions

boundingRect()

QRectF QGraphicsEffectSource::boundingRect

(

Qt::CoordinateSystem

system = Qt::LogicalCoordinates

)

const

Returns the bounding rectangle of the source mapped to the given system.

See also

draw()

Definition at line 161 of file qgraphicseffect.cpp.

{
    return d_func()->boundingRect(system);
}

deviceRect()

QRect QGraphicsEffectSource::deviceRect

(

)

const

draw()

void QGraphicsEffectSource::draw

(

QPainter *

painter

)

Draws the source using the given painter.

This function should only be called from QGraphicsEffect::draw().

See also

QGraphicsEffect::draw()

Definition at line 223 of file qgraphicseffect.cpp.

{
    Q_D(const QGraphicsEffectSource);

    QPixmap pm;
    if (QPixmapCache::find(d->m_cacheKey, &pm)) {
        QTransform restoreTransform;
        if (d->m_cachedSystem == Qt::DeviceCoordinates) {
            restoreTransform = painter->worldTransform();
            painter->setWorldTransform(QTransform());
        }

        painter->drawPixmap(d->m_cachedOffset, pm);

        if (d->m_cachedSystem == Qt::DeviceCoordinates)
            painter->setWorldTransform(restoreTransform);
    } else {
        d_func()->draw(painter);
    }
}

graphicsItem()

const QGraphicsItem * QGraphicsEffectSource::graphicsItem

(

)

const

Returns a pointer to the item if this source is a QGraphicsItem; otherwise returns 0.

See also

widget()

Definition at line 189 of file qgraphicseffect.cpp.

Referenced by pixmap().

{
    return d_func()->graphicsItem();
}

isPixmap()

bool QGraphicsEffectSource::isPixmap

(

)

const

Returns true if the source effectively is a pixmap, e.g., a QGraphicsPixmapItem.

This function is useful for optimization purposes. For instance, there's no point in drawing the source in device coordinates to avoid pixmap scaling if this function returns true - the source pixmap will be scaled anyways.

Definition at line 282 of file qgraphicseffect.cpp.

Referenced by pixmap().

{
    return d_func()->isPixmap();
}

pixmap()

QPixmap QGraphicsEffectSource::pixmap	(	Qt::CoordinateSystem	system = Qt::LogicalCoordinates,
		QPoint *	offset = 0,
		QGraphicsEffect::PixmapPadMode	mode = QGraphicsEffect::PadToEffectiveBoundingRect
	)		const

Returns a pixmap with the source painted into it.

The system specifies which coordinate system to be used for the source. The optional offset parameter returns the offset where the pixmap should be painted at using the current painter.

The mode determines how much of the effect the pixmap will contain. By default, the pixmap will contain the whole effect.

The returned pixmap is bound to the current painter's device rectangle when system is Qt::DeviceCoordinates.

See also

QGraphicsEffect::draw(), boundingRect()

Definition at line 315 of file qgraphicseffect.cpp.

{
    Q_D(const QGraphicsEffectSource);

    // Shortcut, no cache for childless pixmap items...
    const QGraphicsItem *item = graphicsItem();
    if (system == Qt::LogicalCoordinates && mode == QGraphicsEffect::NoPad && item && isPixmap()) {
        const QGraphicsPixmapItem *pixmapItem = static_cast<const QGraphicsPixmapItem *>(item);
        if (offset)
            *offset = pixmapItem->offset().toPoint();
        return pixmapItem->pixmap();
    }

    if (system == Qt::DeviceCoordinates && item
        && !static_cast<const QGraphicsItemEffectSourcePrivate *>(d_func())->info) {
        qWarning("QGraphicsEffectSource::pixmap: Not yet implemented, lacking device context");
        return QPixmap();
    }

    QPixmap pm;
    if (item && d->m_cachedSystem == system && d->m_cachedMode == mode)
        QPixmapCache::find(d->m_cacheKey, &pm);

    if (pm.isNull()) {
        pm = d->pixmap(system, &d->m_cachedOffset, mode);
        d->m_cachedSystem = system;
        d->m_cachedMode = mode;

        d->invalidateCache();
        d->m_cacheKey = QPixmapCache::insert(pm);
    }

    if (offset)
        *offset = d->m_cachedOffset;

    return pm;
}

styleOption()

const QStyleOption * QGraphicsEffectSource::styleOption

(

)

const

Returns a pointer to the style options (used when drawing the source) if available; otherwise returns 0.

See also

graphicsItem(), widget()

Definition at line 211 of file qgraphicseffect.cpp.

{
    return d_func()->styleOption();
}

update()

void QGraphicsEffectSource::update

(

)

Schedules a redraw of the source.

Call this function whenever the source needs to be redrawn.

See also

QGraphicsEffect::updateBoundingRect(), QWidget::update(), QGraphicsItem::update(),

Definition at line 269 of file qgraphicseffect.cpp.

{
    d_func()->update();
}

widget()

const QWidget * QGraphicsEffectSource::widget

(

)

const

Returns a pointer to the widget if this source is a QWidget; otherwise returns 0.

See also

graphicsItem()

Definition at line 200 of file qgraphicseffect.cpp.

{
    return d_func()->widget();
}

Friends and Related Functions

QGraphicsEffect

friend class QGraphicsEffect

friend

Definition at line 92 of file qgraphicseffect_p.h.

QGraphicsEffectPrivate

friend class QGraphicsEffectPrivate

friend

Definition at line 93 of file qgraphicseffect_p.h.

QGraphicsItem

friend class QGraphicsItem

friend

Definition at line 95 of file qgraphicseffect_p.h.

QGraphicsItemPrivate

friend class QGraphicsItemPrivate

friend

Definition at line 96 of file qgraphicseffect_p.h.

QGraphicsScenePrivate

friend class QGraphicsScenePrivate

friend

Definition at line 94 of file qgraphicseffect_p.h.

QWidget

friend class QWidget

friend

Definition at line 97 of file qgraphicseffect_p.h.

QWidgetPrivate

friend class QWidgetPrivate

friend

Definition at line 98 of file qgraphicseffect_p.h.

---

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

• /src/gui/effects/qgraphicseffect_p.h
• /src/gui/effects/qgraphicseffect.cpp