\inmodule QtGui More...

#include <qplatformgraphicsbuffer.h>

Inheritance diagram for QPlatformGraphicsBuffer:

Collaboration diagram for QPlatformGraphicsBuffer:

Public Types
enum	AccessType { None = 0x00 , SWReadAccess = 0x01 , SWWriteAccess = 0x02 , TextureAccess = 0x04 , HWCompositor = 0x08 }
	This enum describes the access that is desired or granted for the graphics buffer. More...

enum	Origin { OriginBottomLeft , OriginTopLeft }
	This enum describes the origin of the content of the buffer. More...

Signals
void	unlocked (AccessTypes previousAccessTypes)
	Signal that is emitted after unlocked has been called.

Signals inherited from QObject
void	destroyed (QObject *=nullptr)
	This signal is emitted immediately before the object obj is destroyed, after any instances of QPointer have been notified, and cannot be blocked.

void	objectNameChanged (const QString &objectName, QPrivateSignal)
	This signal is emitted after the object's name has been changed.

Public Member Functions
	Q_ENUM (AccessType)

	Q_DECLARE_FLAGS (AccessTypes, AccessType)

	Q_ENUM (Origin)

	~QPlatformGraphicsBuffer ()
	Virtual destructor.

AccessTypes	isLocked () const
	Function to check if the buffer is locked.

bool	lock (AccessTypes access, const QRect &rect=QRect())
	Before the data can be retrieved or before a buffer can be bound to a texture it needs to be locked.

void	unlock ()
	Unlocks the current buffer lock.

virtual bool	bindToTexture (const QRect &rect=QRect()) const
	Binds the content of this graphics buffer into the currently bound texture.

virtual const uchar *	data () const
	Accessor for the bytes of the buffer.

virtual uchar *	data ()
	Accessor for the bytes of the buffer.

virtual int	bytesPerLine () const
	Accessor for bytes per line in the graphics buffer.

int	byteCount () const
	Accessor for the length of the data buffer.

virtual Origin	origin () const
	In origin of the content of the graphics buffer.

QSize	size () const
	Accessor for content size.

QPixelFormat	format () const
	Accessor for the pixel format of the buffer.

Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)
	Constructs an object with parent object parent.

virtual	~QObject ()
	Destroys the object, deleting all its child objects.

virtual bool	event (QEvent *event)
	This virtual function receives events to an object and should return true if the event e was recognized and processed.

virtual bool	eventFilter (QObject watched, QEvent event)
	Filters events if this object has been installed as an event filter for the watched object.

QString	objectName () const

Q_WEAK_OVERLOAD void	setObjectName (const QString &name)
	Sets the object's name to name.

void	setObjectName (QAnyStringView name)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

QBindable< QString >	bindableObjectName ()

bool	isWidgetType () const
	Returns `true` if the object is a widget; otherwise returns `false`.

bool	isWindowType () const
	Returns `true` if the object is a window; otherwise returns `false`.

bool	isQuickItemType () const
	Returns `true` if the object is a QQuickItem; otherwise returns `false`.

bool	signalsBlocked () const noexcept
	Returns `true` if signals are blocked; otherwise returns `false`.

bool	blockSignals (bool b) noexcept
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it).

QThread *	thread () const
	Returns the thread in which the object lives.

bool	moveToThread (QThread *thread QT6_DECL_NEW_OVERLOAD_TAIL)
	Changes the thread affinity for this object and its children and returns `true` on success.

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
	This is an overloaded function that will start a timer of type timerType and a timeout of interval milliseconds.

int	startTimer (std::chrono::nanoseconds time, Qt::TimerType timerType=Qt::CoarseTimer)

void	killTimer (int id)
	Kills the timer with timer identifier, id.

void	killTimer (Qt::TimerId id)

template<typename T >
T	findChild (QAnyStringView aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns the child of this object that can be cast into type T and that is called name, or \nullptr if there is no such object.

template<typename T >
QList< T >	findChildren (QAnyStringView aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) 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.

template<typename T >
T	findChild (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

template<typename T >
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

const QObjectList &	children () const
	Returns a list of child objects.

void	setParent (QObject *parent)
	Makes the object a child of parent.

void	installEventFilter (QObject *filterObj)
	Installs an event filter filterObj on this object.

void	removeEventFilter (QObject *obj)
	Removes an event filter object obj from this object.

QMetaObject::Connection	connect (const QObject sender, const char signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const

bool	disconnect (const char signal=nullptr, const QObject receiver=nullptr, const char *member=nullptr) const

bool	disconnect (const QObject receiver, const char member=nullptr) const

void	dumpObjectTree () const
	Dumps a tree of children to the debug output.

void	dumpObjectInfo () const
	Dumps information about signal connections, etc.

bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value.

bool	setProperty (const char *name, QVariant &&value)

QVariant	property (const char *name) const
	Returns the value of the object's name property.

QList< QByteArray >	dynamicPropertyNames () const

QBindingStorage *	bindingStorage ()

const QBindingStorage *	bindingStorage () const

QObject *	parent () const
	Returns a pointer to the parent object.

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`.

Protected Member Functions
	QPlatformGraphicsBuffer (const QSize &size, const QPixelFormat &format)
	Protected constructor to initialize the private members.

virtual bool	doLock (AccessTypes access, const QRect &rect=QRect())=0
	This function should be reimplemented by subclasses.

virtual void	doUnlock ()=0
	This function should remove all locks set on the buffer.

Protected Member Functions inherited from QObject
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 \nullptr.

int	senderSignalIndex () const

int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal.

bool	isSignalConnected (const QMetaMethod &signal) const

virtual void	timerEvent (QTimerEvent *event)
	This event handler can be reimplemented in a subclass to receive timer events for the object.

virtual void	childEvent (QChildEvent *event)
	This event handler can be reimplemented in a subclass to receive child events.

virtual void	customEvent (QEvent *event)
	This event handler can be reimplemented in a subclass to receive custom events.

virtual void	connectNotify (const QMetaMethod &signal)

virtual void	disconnectNotify (const QMetaMethod &signal)

	QObject (QObjectPrivate &dd, QObject *parent=nullptr)

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe

Static Public Member Functions inherited from QObject
static QMetaObject::Connection	connect (const QObject sender, const char signal, const QObject receiver, const char member, Qt::ConnectionType=Qt::AutoConnection)
	\threadsafe

static QMetaObject::Connection	connect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::ContextTypeForFunctor< Func2 >::ContextType context, Func2 &&slot, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 &&slot)

static bool	disconnect (const QObject sender, const char signal, const QObject receiver, const char member)
	\threadsafe

static bool	disconnect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &member)

static bool	disconnect (const QMetaObject::Connection &)
	Disconnect a connection.

template<typename Func1 , typename Func2 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::FunctionPointer< Func2 >::Object receiver, Func2 slot)

template<typename Func1 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const QObject receiver, void **zero)

Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr

Properties inherited from QObject
QString	objectName
	the name of this object

Related Symbols inherited from QObject
template< class T > T	qobject_cast (const QObject *object)
	Returns the given object cast to type T if the object is of type T (or of a subclass); otherwise returns \nullptr.

template< typename T > T	qFindChildqFindChildren (const QObject *obj, const QString &name)()

template< typename T > QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()

	QObjectList
	\macro Q_CLASSINFO(Name, Value)

Detailed Description

\inmodule QtGui

Since: 5.5

The QPlatformGraphicsBuffer is a windowsystem abstraction for native graphics buffers

Different platforms have different ways of representing graphics buffers. On some platforms, it is possible to create one graphics buffer that you can bind to a texture and also get main memory access to the image bits. On the other hand, on some platforms all graphics buffer abstraction is completely hidden.

QPlatformGraphicsBuffer is an abstraction of a single Graphics Buffer.

There is no public constructor nor any public factory function.

Definition at line 26 of file qplatformgraphicsbuffer.h.

Member Enumeration Documentation

◆ AccessType

enum QPlatformGraphicsBuffer::AccessType

This enum describes the access that is desired or granted for the graphics buffer.

\value None \value SWReadAccess \value SWWriteAccess \value TextureAccess \value HWCompositor

Enumerator
None
SWReadAccess
SWWriteAccess
TextureAccess
HWCompositor

Definition at line 30 of file qplatformgraphicsbuffer.h.

◆ Origin

enum QPlatformGraphicsBuffer::Origin

This enum describes the origin of the content of the buffer.

\value OriginTopLeft \value OriginBottomLeft

Enumerator
OriginBottomLeft
OriginTopLeft

Definition at line 41 of file qplatformgraphicsbuffer.h.

Constructor & Destructor Documentation

◆ ~QPlatformGraphicsBuffer()

QPlatformGraphicsBuffer::~QPlatformGraphicsBuffer ( )

Virtual destructor.

Definition at line 70 of file qplatformgraphicsbuffer.cpp.

◆ QPlatformGraphicsBuffer()

QPlatformGraphicsBuffer::QPlatformGraphicsBuffer	(	const QSize &	size,
		const QPixelFormat &	format )

protected

Protected constructor to initialize the private members.

size is the size of the buffer. format is the format of the buffer.

See also: size() format()

Definition at line 60 of file qplatformgraphicsbuffer.cpp.

Member Function Documentation

◆ bindToTexture()

bool QPlatformGraphicsBuffer::bindToTexture ( const QRect & rect = QRect() ) const

virtual

Binds the content of this graphics buffer into the currently bound texture.

This function should fail for buffers not capable of locking to TextureAccess.

rect is the subrect which is desired to be bounded to the texture. This argument has a no less than semantic, meaning more (if not all) of the buffer can be bounded to the texture. An empty QRect is interpreted as entire buffer should be bound.

This function only supports binding buffers to the GL_TEXTURE_2D texture target.

Returns true on success, otherwise false.

Definition at line 89 of file qplatformgraphicsbuffer.cpp.

◆ byteCount()

int QPlatformGraphicsBuffer::byteCount ( ) const

Accessor for the length of the data buffer.

This function is a convenience function multiplying height of buffer with bytesPerLine().

See also: data() bytesPerLine() size()

Definition at line 198 of file qplatformgraphicsbuffer.cpp.

◆ bytesPerLine()

int QPlatformGraphicsBuffer::bytesPerLine ( ) const

virtual

Accessor for bytes per line in the graphics buffer.

Reimplemented in QIOSurfaceGraphicsBuffer, QXcbGraphicsBuffer, and QXcbGraphicsBuffer.

Definition at line 206 of file qplatformgraphicsbuffer.cpp.

◆ data() [1/2]

uchar * QPlatformGraphicsBuffer::data ( )

virtual

Accessor for the bytes of the buffer.

This function needs to be called on a buffer with SWReadAccess access lock. Behavior is undefined for modifying the memory returned when not having a SWWriteAccess.

Reimplemented in QIOSurfaceGraphicsBuffer, QXcbGraphicsBuffer, and QXcbGraphicsBuffer.

Definition at line 187 of file qplatformgraphicsbuffer.cpp.

◆ data() [2/2]

const uchar * QPlatformGraphicsBuffer::data ( ) const

virtual

Accessor for the bytes of the buffer.

This function needs to be called on a buffer with SWReadAccess access lock. Behavior is undefined for modifying the memory returned when not having a SWWriteAccess.

Reimplemented in QIOSurfaceGraphicsBuffer, QXcbGraphicsBuffer, and QXcbGraphicsBuffer.

Definition at line 179 of file qplatformgraphicsbuffer.cpp.

◆ doLock()

virtual bool QPlatformGraphicsBuffer::doLock	(	AccessTypes	access,
		const QRect &	rect = QRect() )

protectedpure virtual

This function should be reimplemented by subclasses.

If one of the access types specified cannot be locked, then all should fail and this function should return false.

rect is the subrect which is desired to be locked. This argument has a no less than semantic, meaning more (if not all) of the buffer can be locked. An empty QRect should be interpreted as the entire buffer should be locked.

It is safe to call isLocked() to verify the current lock state.

Implemented in QIOSurfaceGraphicsBuffer, QXcbGraphicsBuffer, and QXcbGraphicsBuffer.

◆ doUnlock()

virtual void QPlatformGraphicsBuffer::doUnlock ( )

protectedpure virtual

This function should remove all locks set on the buffer.

It is safe to call isLocked() to verify the current lock state.

Implemented in QIOSurfaceGraphicsBuffer, QXcbGraphicsBuffer, and QXcbGraphicsBuffer.

◆ format()

QPixelFormat QPlatformGraphicsBuffer::format ( ) const

inline

Accessor for the pixel format of the buffer.

Definition at line 63 of file qplatformgraphicsbuffer.h.

◆ isLocked()

AccessTypes QPlatformGraphicsBuffer::isLocked ( ) const

inline

Function to check if the buffer is locked.

See also: lock()

Definition at line 49 of file qplatformgraphicsbuffer.h.

◆ lock()

bool QPlatformGraphicsBuffer::lock	(	AccessTypes	access,
		const QRect &	rect = QRect() )

Before the data can be retrieved or before a buffer can be bound to a texture it needs to be locked.

This is a separate function call since this operation might be time consuming, and it would not be satisfactory to do it per function call.

access is the access type wanted.

rect is the subrect which is desired to be locked. This argument has a no less than semantic, meaning more (if not all) of the buffer can be locked. An empty QRect is interpreted as entire buffer should be locked.

Return true on successfully locking all AccessTypes specified access otherwise returns false and no locks have been granted.

Definition at line 117 of file qplatformgraphicsbuffer.cpp.

◆ origin()

QPlatformGraphicsBuffer::Origin QPlatformGraphicsBuffer::origin ( ) const

virtual

In origin of the content of the graphics buffer.

Default implementation is OriginTopLeft, as this is the coordinate system default for Qt. However, for most regular OpenGL textures this will be OriginBottomLeft.

Reimplemented in QXcbGraphicsBuffer, and QXcbGraphicsBuffer.

Definition at line 219 of file qplatformgraphicsbuffer.cpp.

◆ Q_DECLARE_FLAGS()

QPlatformGraphicsBuffer::Q_DECLARE_FLAGS	(	AccessTypes	,
		AccessType	)

◆ Q_ENUM() [1/2]

QPlatformGraphicsBuffer::Q_ENUM ( AccessType )

◆ Q_ENUM() [2/2]

QPlatformGraphicsBuffer::Q_ENUM ( Origin )

◆ size()

QSize QPlatformGraphicsBuffer::size ( ) const

inline

Accessor for content size.

Definition at line 62 of file qplatformgraphicsbuffer.h.

◆ unlock()

void QPlatformGraphicsBuffer::unlock ( )

Unlocks the current buffer lock.

This function calls doUnlock, and then emits the unlocked signal with the AccessTypes from before doUnlock was called.

Definition at line 132 of file qplatformgraphicsbuffer.cpp.

◆ unlocked

void QPlatformGraphicsBuffer::unlocked ( AccessTypes previousAccessTypes )

signal

Signal that is emitted after unlocked has been called.

previousAccessTypes is the access types locked before unlock was called.

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

qtbase/src/gui/kernel/qplatformgraphicsbuffer.h (05fc3aef53348fb58be6308076e000825b704e58)
qtbase/src/gui/kernel/qplatformgraphicsbuffer.cpp (05fc3aef53348fb58be6308076e000825b704e58)

Public Types

Signals

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ AccessType

◆ Origin

Constructor & Destructor Documentation

◆ ~QPlatformGraphicsBuffer()

◆ QPlatformGraphicsBuffer()

Member Function Documentation

◆ bindToTexture()

◆ byteCount()

◆ bytesPerLine()

◆ data() [1/2]

◆ data() [2/2]

◆ doLock()

◆ doUnlock()

◆ format()

◆ isLocked()

◆ lock()

◆ origin()

◆ Q_DECLARE_FLAGS()

◆ Q_ENUM() [1/2]

◆ Q_ENUM() [2/2]

◆ size()

◆ unlock()

◆ unlocked