#include <qplatformsharedgraphicscache.h>

Inheritance diagram for QPlatformSharedGraphicsCache:

Collaboration diagram for QPlatformSharedGraphicsCache:

Public Types
enum	PixelFormat { Alpha8 }

enum	BufferType { OpenGLTexture }

Signals
void	itemsMissing (const QByteArray &cacheId, const QList< quint32 > &itemIds)

void	itemsAvailable (const QByteArray &cacheId, void *bufferId, const QList< quint32 > &itemIds, const QList< QPoint > &positionsInBuffer)

void	itemsInvalidated (const QByteArray &cacheId, const QList< quint32 > &itemIds)

void	itemsUpdated (const QByteArray &cacheId, void *bufferId, const QList< quint32 > &itemIds, const QList< QPoint > &positionsInBuffer)

Signals inherited from QObject
void	destroyed (QObject *=nullptr)

void	objectNameChanged (const QString &objectName, QPrivateSignal)

Public Member Functions
	QPlatformSharedGraphicsCache (QObject *parent=nullptr)

virtual void	beginRequestBatch ()=0

virtual void	ensureCacheInitialized (const QByteArray &cacheId, BufferType bufferType, PixelFormat pixelFormat)=0

virtual void	requestItems (const QByteArray &cacheId, const QList< quint32 > &itemIds)=0

virtual void	insertItems (const QByteArray &cacheId, const QList< quint32 > &itemIds, const QList< QImage > &items)=0

virtual void	releaseItems (const QByteArray &cacheId, const QList< quint32 > &itemIds)=0

virtual void	endRequestBatch ()=0

virtual bool	requestBatchStarted () const =0

virtual uint	textureIdForBuffer (void *bufferId)=0

virtual void	referenceBuffer (void *bufferId)=0

virtual bool	dereferenceBuffer (void *bufferId)=0

virtual QSize	sizeOfBuffer (void *bufferId)=0

virtual void *	eglImageForBuffer (void *bufferId)=0

Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)

virtual	~QObject ()

virtual bool	event (QEvent *event)

virtual bool	eventFilter (QObject watched, QEvent event)

QString	objectName () const

void	setObjectName (const QString &name)

QBindable< QString >	bindableObjectName ()

bool	isWidgetType () const

bool	isWindowType () const

bool	signalsBlocked () const noexcept

bool	blockSignals (bool b) noexcept

QThread *	thread () const

void	moveToThread (QThread *thread)

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)

void	killTimer (int id)

template<typename T >
T	findChild (const QString &aName=QString(), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

template<typename T >
QList< T >	findChildren (const QString &aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

template<typename T >
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

const QObjectList &	children () const

void	setParent (QObject *parent)

void	installEventFilter (QObject *filterObj)

void	removeEventFilter (QObject *obj)

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

void	dumpObjectInfo () const

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

QVariant	property (const char *name) const

QList< QByteArray >	dynamicPropertyNames () const

QBindingStorage *	bindingStorage ()

const QBindingStorage *	bindingStorage () const

QObject *	parent () const

bool	inherits (const char *classname) const

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

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)

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::FunctionPointer< Func2 >::Object receiver, Func2 slot, Qt::ConnectionType type=Qt::AutoConnection)

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

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

template<typename Func1 , typename Func2 >
static std::enable_if< QtPrivate::FunctionPointer< Func2 >::ArgumentCount==-1 &&!std::is_convertible_v< Func2, const char * >, QMetaObject::Connection >::type	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 slot)

template<typename Func1 , typename Func2 >
static std::enable_if< QtPrivate::FunctionPointer< Func2 >::ArgumentCount==-1 &&!std::is_convertible_v< Func2, const char * >, QMetaObject::Connection >::type	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const QObject context, Func2 slot, Qt::ConnectionType type=Qt::AutoConnection)

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

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

static bool	disconnect (const QMetaObject::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 Member Functions inherited from QObject
QObject *	sender () const

int	senderSignalIndex () const

int	receivers (const char *signal) const

bool	isSignalConnected (const QMetaMethod &signal) const

virtual void	timerEvent (QTimerEvent *event)

virtual void	childEvent (QChildEvent *event)

virtual void	customEvent (QEvent *event)

virtual void	connectNotify (const QMetaMethod &signal)

virtual void	disconnectNotify (const QMetaMethod &signal)

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

Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr

Properties inherited from QObject
QString	objectName
	the name of this object More...

Related Functions inherited from QObject
template< class T > T	qobject_cast (const QObject *object)

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

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

	QObjectList

Detailed Description

Since: 5.0

Definition at line 58 of file qplatformsharedgraphicscache.h.

Member Enumeration Documentation

◆ BufferType

enum QPlatformSharedGraphicsCache::BufferType

Defines how the type of buffer required to contain a cache.

\value OpenGLTexture The buffer will be allocated in graphics memory, and an OpenGL texture for a buffer belonging to the cache can be requested using textureIdForBuffer().

Enumerator
OpenGLTexture

Definition at line 67 of file qplatformsharedgraphicscache.h.

◆ PixelFormat

enum QPlatformSharedGraphicsCache::PixelFormat

Defines the pixel format of a cache.

\value Alpha8 The cache will use 8 bits to represent the alpha value of each pixel. If an OpenGL texture is created for a buffer belong to the cache, it will have the pixel format GL_ALPHA.

Enumerator
Alpha8

Definition at line 62 of file qplatformsharedgraphicscache.h.

Constructor & Destructor Documentation

◆ QPlatformSharedGraphicsCache()

QPlatformSharedGraphicsCache::QPlatformSharedGraphicsCache ( QObject * parent = nullptr )

inlineexplicit

Definition at line 72 of file qplatformsharedgraphicscache.h.

Member Function Documentation

◆ beginRequestBatch()

void QPlatformSharedGraphicsCache::beginRequestBatch ( )

pure virtual

This is a hint to the cache that a burst of requests is pending. In some implementations, this will improve performance, as the cache can focus on handling the requests and wait with the results until it is done. It should typically be called prior to a sequence of calls to requestItems() and releaseItems().

Any call to beginRequestBatch() must be followed at some point by a call to endRequestBatch(). Failing to do this may lead to the results of requests never being emitted.

Note: beginRequestBatch() and endRequestBatch() have no stacking logic. Calling beginRequestBatch() twice in a row has no effect, and the single existing batch will be ended by the earliest call to endRequestBatch().

See also: endRequestBatch(), requestBatchStarted()

◆ dereferenceBuffer()

bool QPlatformSharedGraphicsCache::dereferenceBuffer ( void * bufferId )

pure virtual

Removed a previously registered reference to the buffer bufferId. Returns true if there are still more references to the buffer in question, or false if this was the last reference (in which case the buffer may have been deleted in the cache.)

See also: dereferenceBuffer()

◆ eglImageForBuffer()

void * QPlatformSharedGraphicsCache::eglImageForBuffer ( void * bufferId )

pure virtual

Returns an EGLImageKHR image corresponding to the buffer bufferId.

See also: textureIdForBuffer(), sizeOfBuffer()

◆ endRequestBatch()

void QPlatformSharedGraphicsCache::endRequestBatch ( )

pure virtual

Signals to the cache that the request sequence which has previously been commenced using beginRequestBatch() has now finished.

See also: beginRequestBatch(), requestBatchStarted()

◆ ensureCacheInitialized()

void QPlatformSharedGraphicsCache::ensureCacheInitialized	(	const QByteArray &	cacheId,
		BufferType	bufferType,
		PixelFormat	pixelFormat
	)

pure virtual

Initializes a cache named cacheId if it has not yet been initialized. The bufferType and pixelFormat gives the format of the buffers that will be used to contain the items in the cache. If a cache with the same cacheId has previously been initialized, the call will be ignored. The cache will keep its previously set buffer type and pixel format.

◆ insertItems()

void QPlatformSharedGraphicsCache::insertItems	(	const QByteArray &	cacheId,
		const QList< quint32 > &	itemIds,
		const QList< QImage > &	items
	)

pure virtual

Inserts the items in itemIds into the cache named cacheId. The appearance of each item is stored in items. The format of the QImage objects is expected to match the pixel format of the cache as it was initialized in ensureCacheInitialized().

When the items have been successfully entered into the cache, one or more itemsAvailable() signals will be emitted for the items.

If the cache already contains the items, the behavior is implementation-specific. The implementation may choose to ignore the items or it may overwrite the existing instances in the cache. Either way, itemsAvailable() signals corresponding to the inserted items will be emitted.

◆ itemsAvailable

void QPlatformSharedGraphicsCache::itemsAvailable	(	const QByteArray &	cacheId,
		void *	bufferId,
		const QList< quint32 > &	itemIds,
		const QList< QPoint > &	positionsInBuffer
	)

signal

This signal can be emitted at any time when either requestItems() or insertItems() has been called by the application for one or more items in the cache named cacheId, as long as releaseItems() has not subsequently been called for the same items. It instructs the application on where to find the items that have been entered into the cache. When the application receives a buffer, it is expected to reference it using referenceBuffer() on it if it keeps a reference to the buffer.

The bufferId is an ID for the buffer that contains the items. The bufferId can be converted to a format usable by the application depending on which format it was given at initialization. If it is a OpenGLTexture, its texture ID can be requested using the textureIdForBuffer() function. The dimensions of the buffer are given by bufferSize.

The items provided by the cache are identified in the itemIds list. The positionsInBuffer list contains the locations inside the buffer of each item. Each entry in positionsInBuffer corresponds to an item in itemIds.

The buffer and the items' locations within the buffer can be considered valid until an itemsInvalidated() signal has been emitted for the items, or until releaseItems() is called for the items.

See also: itemsMissing(), requestItems(), bufferType()

◆ itemsInvalidated

void QPlatformSharedGraphicsCache::itemsInvalidated	(	const QByteArray &	cacheId,
		const QList< quint32 > &	itemIds
	)

signal

This signal is emitted when the items given by itemIds in the cache named cacheId have been removed from the cache and the previously reported information about them is considered invalid. It will only be emitted for items for which a buffer has previously been identified through the itemsAvailable() signal (either as response to a requestItems() call or an insertItems() call.)

The application is expected to throw away information about the items in the itemIds array and drop any references it might have to the memory held by the buffer. If the items are still required by the application, it can re-commit them to the cache using the insertItems() function.

If the application no longer holds any references to previously referenced items in a given cache, it should call releaseItems() for these items, at which point it will no longer receive any itemsInvalidated() signal for these items.

◆ itemsMissing

void QPlatformSharedGraphicsCache::itemsMissing	(	const QByteArray &	cacheId,
		const QList< quint32 > &	itemIds
	)

signal

This signal is emitted when requestItems() has been called for one or more items in the cache named cacheId which are not yet available in the cache. The user is then expected to call insertItems() to update the cache with the respective items, at which point they will become available to all clients of the shared cache.

The itemIds list contains the IDs of the items that need to be inserted into the cache.

See also: itemsAvailable(), insertItems(), requestItems()

◆ itemsUpdated

void QPlatformSharedGraphicsCache::itemsUpdated	(	const QByteArray &	cacheId,
		void *	bufferId,
		const QList< quint32 > &	itemIds,
		const QList< QPoint > &	positionsInBuffer
	)

signal

This signal is similar in usage to the itemsAvailable() signal, but will be emitted when the location of a previously requested or inserted item has been updated. The application must update its data for the respective items and release any references to old buffers held by the items.

If the application no longer holds any references to previously referenced items in a given cache, it should call releaseItems() for these items, at which point it will no longer receive any itemsUpdated() signal for these items.

See also: requestItems(), insertItems(), itemsAvailable()

◆ referenceBuffer()

void QPlatformSharedGraphicsCache::referenceBuffer ( void * bufferId )

pure virtual

Registers a reference to the buffer bufferId.

See also: dereferenceBuffer()

◆ releaseItems()

void QPlatformSharedGraphicsCache::releaseItems	(	const QByteArray &	cacheId,
		const QList< quint32 > &	itemIds
	)

pure virtual

Releases the reference to the items in itemIds from the cache named cacheId. This should only be called when all references to the items have been released by the user, and they are no longer needed.

◆ requestBatchStarted()

bool QPlatformSharedGraphicsCache::requestBatchStarted ( ) const

pure virtual

Returns true if a request batch has previously been started using beginRequestBatch() and not yet stopped using endRequestBatch().

See also: beginRequestBatch(), endRequestBatch()

◆ requestItems()

void QPlatformSharedGraphicsCache::requestItems	(	const QByteArray &	cacheId,
		const QList< quint32 > &	itemIds
	)

pure virtual

Requests all the items in itemIds from the cache with the name cacheId.

If any or all of the items are available in the cache, one or more itemsAvailable() signals will be emitted corresponding to the items. If the cache does not contain all of the items in question, then an itemsMissing() signal will be emitted corresponding to the missing items. The user is at this point expected to call insertItems() to insert the missing items into the cache. If the inserted items have previously been requested by the user, at which point an itemsAvailable() signal will be emitted corresponding to the items.

Before requesting items from a cache, the user must call ensureCacheInitialized() with the correct parameters for the cache.

◆ sizeOfBuffer()

QSize QPlatformSharedGraphicsCache::sizeOfBuffer ( void * bufferId )

pure virtual

Returns the size of the buffer bufferId.

See also: textureIdForBuffer(), eglImageForBuffer()

◆ textureIdForBuffer()

uint QPlatformSharedGraphicsCache::textureIdForBuffer ( void * bufferId )

pure virtual

Returns an OpenGL texture ID corresponding to the buffer bufferId, which has previously been passed through signals itemsAvailable() or itemsUpdated(). The relevant OpenGL context should be current when calling this function.

See also: eglImageForBuffer(), sizeOfBuffer()

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

src/gui/kernel/qplatformsharedgraphicscache.h
src/gui/kernel/qplatformsharedgraphicscache.cpp

Public Types

Signals

Public Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ BufferType

◆ PixelFormat

Constructor & Destructor Documentation

◆ QPlatformSharedGraphicsCache()

Member Function Documentation

◆ beginRequestBatch()

◆ dereferenceBuffer()

◆ eglImageForBuffer()

◆ endRequestBatch()

◆ ensureCacheInitialized()

◆ insertItems()

◆ itemsAvailable

◆ itemsInvalidated

◆ itemsMissing

◆ itemsUpdated

◆ referenceBuffer()

◆ releaseItems()

◆ requestBatchStarted()

◆ requestItems()

◆ sizeOfBuffer()

◆ textureIdForBuffer()