\inmodule QtQuick More...

#include <qsgtexture.h>

Inheritance diagram for QSGTexture:

Collaboration diagram for QSGTexture:

Public Types
enum	WrapMode { Repeat , ClampToEdge , MirroredRepeat }
	Specifies how the sampler should treat texture coordinates. More...

enum	Filtering { None , Nearest , Linear }
	Specifies how sampling of texels should filter when texture coordinates are not pixel aligned. More...

enum	AnisotropyLevel { AnisotropyNone , Anisotropy2x , Anisotropy4x , Anisotropy8x , Anisotropy16x }
	Specifies the anisotropic filtering level to be used when the texture is not screen aligned. More...

Public Member Functions
	QSGTexture ()
	Constructs the QSGTexture base class.

	~QSGTexture () override
	Destroys the QSGTexture.

virtual qint64	comparisonKey () const =0
	Returns a key suitable for comparing textures.

virtual QRhiTexture *	rhiTexture () const

virtual QSize	textureSize () const =0
	Returns the size of the texture in pixels.

virtual bool	hasAlphaChannel () const =0
	Returns true if the texture data contains an alpha channel.

virtual bool	hasMipmaps () const =0
	Returns true if the texture data contains mipmap levels.

virtual QRectF	normalizedTextureSubRect () const
	Returns the rectangle inside textureSize() that this texture represents in normalized coordinates.

virtual bool	isAtlasTexture () const
	Returns whether this texture is part of an atlas or not.

virtual QSGTexture *	removedFromAtlas (QRhiResourceUpdateBatch *resourceUpdates=nullptr) const
	This function returns a copy of the current texture which is removed from its atlas.

virtual void	commitTextureOperations (QRhi rhi, QRhiResourceUpdateBatch resourceUpdates)
	Call this function to enqueue image upload operations to resourceUpdates, in case there are any pending ones.

void	setMipmapFiltering (Filtering filter)
	Sets the mipmap sampling mode to filter.

QSGTexture::Filtering	mipmapFiltering () const
	Returns whether mipmapping should be used when sampling from this texture.

void	setFiltering (Filtering filter)
	Sets the sampling mode to filter.

QSGTexture::Filtering	filtering () const
	Returns the sampling mode to be used for this texture.

void	setAnisotropyLevel (AnisotropyLevel level)
	Sets the level of anisotropic filtering to level.

QSGTexture::AnisotropyLevel	anisotropyLevel () const
	Returns the anisotropy level in use for filtering this texture.

void	setHorizontalWrapMode (WrapMode hwrap)
	Sets the horizontal wrap mode to hwrap.

QSGTexture::WrapMode	horizontalWrapMode () const
	Returns the horizontal wrap mode to be used for this texture.

void	setVerticalWrapMode (WrapMode vwrap)
	Sets the vertical wrap mode to vwrap.

QSGTexture::WrapMode	verticalWrapMode () const
	Returns the vertical wrap mode to be used for this texture.

QRectF	convertToNormalizedSourceRect (const QRectF &rect) const
	Returns rect converted to normalized coordinates.

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
	QSGTexture (QSGTexturePrivate &dd)

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

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.

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 QtQuick

The QSGTexture class is the base class for textures used in the scene graph.

Users can freely implement their own texture classes to support arbitrary input textures, such as YUV video frames or 8 bit alpha masks. The scene graph provides a default implementation for RGBA textures.The default implementation is not instantiated directly, rather they are constructed via factory functions, such as QQuickWindow::createTextureFromImage().

With the default implementation, each QSGTexture is backed by a QRhiTexture, which in turn contains a native texture object, such as an OpenGL texture or a Vulkan image.

The size in pixels is given by textureSize(). hasAlphaChannel() reports if the texture contains opacity values and hasMipmaps() reports if the texture contains mipmap levels.

\l{QSGMaterial}{Materials} that work with textures reimplement \l{QSGMaterialShader::updateSampledImage()}{updateSampledImage()} to provide logic that decides which QSGTexture's underlying native texture should be exposed at a given shader resource binding point.

QSGTexture does not separate image (texture) and sampler objects. The parameters for filtering and wrapping can be specified with setMipmapFiltering(), setFiltering(), setHorizontalWrapMode() and setVerticalWrapMode(). The scene graph and Qt's graphics abstraction takes care of creating separate sampler objects, when applicable.

Definition at line 19 of file qsgtexture.h.

Member Enumeration Documentation

◆ AnisotropyLevel

enum QSGTexture::AnisotropyLevel

Specifies the anisotropic filtering level to be used when the texture is not screen aligned.

\value AnisotropyNone No anisotropic filtering.

\value Anisotropy2x 2x anisotropic filtering.

\value Anisotropy4x 4x anisotropic filtering.

\value Anisotropy8x 8x anisotropic filtering.

\value Anisotropy16x 16x anisotropic filtering.

Since: 5.9

Enumerator
AnisotropyNone
Anisotropy2x
Anisotropy4x
Anisotropy8x
Anisotropy16x

Definition at line 40 of file qsgtexture.h.

◆ Filtering

enum QSGTexture::Filtering

Specifies how sampling of texels should filter when texture coordinates are not pixel aligned.

\value None No filtering should occur. This value is only used together with setMipmapFiltering().

\value Nearest Sampling returns the nearest texel.

\value Linear Sampling returns a linear interpolation of the neighboring texels.

Enumerator
None
Nearest
Linear

Definition at line 34 of file qsgtexture.h.

◆ WrapMode

enum QSGTexture::WrapMode

Specifies how the sampler should treat texture coordinates.

\value Repeat Only the fractional part of the texture coordinate is used, causing values above 1 and below 0 to repeat.

\value ClampToEdge Values above 1 are clamped to 1 and values below 0 are clamped to 0.

\value MirroredRepeat When the texture coordinate is even, only the fractional part is used. When odd, the texture coordinate is set to {1 - fractional part}. This value has been introduced in Qt 5.10.

Enumerator
Repeat
ClampToEdge
MirroredRepeat

Definition at line 28 of file qsgtexture.h.

Constructor & Destructor Documentation

◆ QSGTexture() [1/2]

QSGTexture::QSGTexture ( )

Constructs the QSGTexture base class.

Definition at line 302 of file qsgtexture.cpp.

◆ ~QSGTexture()

QSGTexture::~QSGTexture ( )

override

Destroys the QSGTexture.

Definition at line 332 of file qsgtexture.cpp.

◆ QSGTexture() [2/2]

QSGTexture::QSGTexture ( QSGTexturePrivate & dd )

protected

Definition at line 317 of file qsgtexture.cpp.

Member Function Documentation

◆ anisotropyLevel()

QSGTexture::AnisotropyLevel QSGTexture::anisotropyLevel ( ) const

Returns the anisotropy level in use for filtering this texture.

Since: 5.9

Definition at line 519 of file qsgtexture.cpp.

◆ commitTextureOperations()

void QSGTexture::commitTextureOperations	(	QRhi *	rhi,
		QRhiResourceUpdateBatch *	resourceUpdates )

virtual

Call this function to enqueue image upload operations to resourceUpdates, in case there are any pending ones.

When there is no new data (for example, because there was no setImage() since the last call to this function), the function does nothing.

Materials involving rhi textures are expected to call this function from their \l{QSGMaterialShader::updateSampledImage()}{updateSampledImage()} implementation, typically without any conditions, passing {state.rhi()} and {state.resourceUpdateBatch()} from the QSGMaterialShader::RenderState.

Warning: This function can only be called from the rendering thread.

Since: 6.0

Reimplemented in QSGCompressedTexture, QSGPainterTexture, QSGPlainTexture, QSGRhiAtlasTexture::TextureBase, and QSGRhiLayer.

Definition at line 603 of file qsgtexture.cpp.

◆ comparisonKey()

virtual qint64 QSGTexture::comparisonKey ( ) const

pure virtual

Returns a key suitable for comparing textures.

Typically used in QSGMaterial::compare() implementations.

Just comparing QSGTexture pointers is not always sufficient because two QSGTexture instances that refer to the same native texture object underneath should also be considered equal. Hence the need for this function.

Implementations of this function are not expected to, and should not create any graphics resources (native texture objects) in case there are none yet.

A QSGTexture that does not have a native texture object underneath is typically not equal to any other QSGTexture, so the return value has to be crafted accordingly. There are exceptions to this, in particular when atlasing is used (where multiple textures share the same atlas texture under the hood), that is then up to the subclass implementations to deal with as appropriate.

Warning: This function can only be called from the rendering thread.

Since: 5.14

Implemented in QSGCompressedTexture, QSGOpenVGLayer, QSGOpenVGTexture, QSGPlainTexture, QSGRhiAtlasTexture::TextureBase, QSGRhiLayer, QSGSoftwareLayer, QSGSoftwarePixmapTexture, and QSGVideoTexture.

◆ convertToNormalizedSourceRect()

QRectF QSGTexture::convertToNormalizedSourceRect ( const QRectF & rect ) const

inline

Returns rect converted to normalized coordinates.

See also: normalizedTextureSubRect()

Definition at line 85 of file qsgtexture.h.

◆ filtering()

QSGTexture::Filtering QSGTexture::filtering ( ) const

Returns the sampling mode to be used for this texture.

Definition at line 490 of file qsgtexture.cpp.

◆ hasAlphaChannel()

virtual bool QSGTexture::hasAlphaChannel ( ) const

pure virtual

Returns true if the texture data contains an alpha channel.

Implemented in QSGCompressedAtlasTexture::Texture, QSGCompressedTexture, QSGOpenVGLayer, QSGOpenVGTexture, QSGPlainTexture, QSGRhiAtlasTexture::Texture, QSGRhiLayer, QSGSoftwareLayer, QSGSoftwarePixmapTexture, and QSGVideoTexture.

◆ hasMipmaps()

virtual bool QSGTexture::hasMipmaps ( ) const

pure virtual

Returns true if the texture data contains mipmap levels.

Implemented in QSGCompressedAtlasTexture::Texture, QSGCompressedTexture, QSGOpenVGLayer, QSGOpenVGTexture, QSGPlainTexture, QSGRhiAtlasTexture::Texture, QSGRhiLayer, QSGSoftwareLayer, QSGSoftwarePixmapTexture, and QSGVideoTexture.

◆ horizontalWrapMode()

QSGTexture::WrapMode QSGTexture::horizontalWrapMode ( ) const

Returns the horizontal wrap mode to be used for this texture.

Definition at line 542 of file qsgtexture.cpp.

◆ isAtlasTexture()

bool QSGTexture::isAtlasTexture ( ) const

virtual

Returns whether this texture is part of an atlas or not.

The default implementation returns false.

Reimplemented in QSGRhiAtlasTexture::TextureBase.

Definition at line 389 of file qsgtexture.cpp.

◆ mipmapFiltering()

QSGTexture::Filtering QSGTexture::mipmapFiltering ( ) const

Returns whether mipmapping should be used when sampling from this texture.

Definition at line 469 of file qsgtexture.cpp.

◆ normalizedTextureSubRect()

QRectF QSGTexture::normalizedTextureSubRect ( ) const

virtual

Returns the rectangle inside textureSize() that this texture represents in normalized coordinates.

The default implementation returns a rect at position (0, 0) with width and height of 1.

Reimplemented in QSGCompressedAtlasTexture::Texture, QSGRhiAtlasTexture::Texture, and QSGRhiLayer.

Definition at line 432 of file qsgtexture.cpp.

◆ removedFromAtlas()

QSGTexture * QSGTexture::removedFromAtlas ( QRhiResourceUpdateBatch * resourceUpdates = nullptr ) const

virtual

This function returns a copy of the current texture which is removed from its atlas.

The current texture remains unchanged, so texture coordinates do not need to be updated.

Removing a texture from an atlas is primarily useful when passing it to a shader that operates on the texture coordinates 0-1 instead of the texture subrect inside the atlas.

If the texture is not part of a texture atlas, this function returns 0.

Implementations of this function are recommended to return the same instance for multiple calls to limit memory usage.

resourceUpdates is an optional resource update batch, on which texture operations, if any, are enqueued. Materials can retrieve an instance from QSGMaterialShader::RenderState. When null, the removedFromAtlas() implementation creates its own batch and submit it right away. However, when a valid instance is specified, this function will not submit the update batch.

Warning: This function can only be called from the rendering thread.

Reimplemented in QSGCompressedAtlasTexture::Texture, and QSGRhiAtlasTexture::Texture.

Definition at line 377 of file qsgtexture.cpp.

◆ rhiTexture()

QRhiTexture * QSGTexture::rhiTexture ( ) const

virtual

Returns: the QRhiTexture for this QSGTexture or null if there is none (either because a valid texture has not been created internally yet, or because the concept is not applicable to the scenegraph backend in use).

This function is not expected to create a new QRhiTexture in case there is none. It should return null in that case. The expectation towards the renderer is that a null texture leads to using a transparent, dummy texture instead.

Warning: This function can only be called from the rendering thread.

Since: 6.0

Reimplemented in QSGCompressedTexture, QSGPlainTexture, QSGRhiAtlasTexture::TextureBase, QSGRhiLayer, and QSGVideoTexture.

Definition at line 583 of file qsgtexture.cpp.

◆ setAnisotropyLevel()

void QSGTexture::setAnisotropyLevel ( AnisotropyLevel level )

Sets the level of anisotropic filtering to level.

The default value is QSGTexture::AnisotropyNone, which means no anisotropic filtering is enabled.

Note: The request may be ignored depending on the graphics API in use. There is no guarantee anisotropic filtering is supported at run time.

Since: 5.9

Definition at line 505 of file qsgtexture.cpp.

◆ setFiltering()

void QSGTexture::setFiltering ( QSGTexture::Filtering filter )

Sets the sampling mode to filter.

Definition at line 478 of file qsgtexture.cpp.

◆ setHorizontalWrapMode()

void QSGTexture::setHorizontalWrapMode ( WrapMode hwrap )

Sets the horizontal wrap mode to hwrap.

Definition at line 530 of file qsgtexture.cpp.

◆ setMipmapFiltering()

void QSGTexture::setMipmapFiltering ( Filtering filter )

Sets the mipmap sampling mode to filter.

Setting the mipmap filtering has no effect it the texture does not have mipmaps.

See also: hasMipmaps()

Definition at line 457 of file qsgtexture.cpp.

◆ setVerticalWrapMode()

void QSGTexture::setVerticalWrapMode ( WrapMode vwrap )

Sets the vertical wrap mode to vwrap.

Definition at line 552 of file qsgtexture.cpp.

◆ textureSize()

virtual QSize QSGTexture::textureSize ( ) const

pure virtual

Returns the size of the texture in pixels.

Implemented in QSGCompressedAtlasTexture::Texture, QSGCompressedTexture, QSGOpenVGLayer, QSGOpenVGTexture, QSGPlainTexture, QSGRhiAtlasTexture::Texture, QSGRhiLayer, QSGSoftwareLayer, QSGSoftwarePixmapTexture, and QSGVideoTexture.

◆ verticalWrapMode()

QSGTexture::WrapMode QSGTexture::verticalWrapMode ( ) const

Returns the vertical wrap mode to be used for this texture.

Definition at line 564 of file qsgtexture.cpp.

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

qtdeclarative/src/quick/scenegraph/coreapi/qsgtexture.h (de05c6202cc16ab749d217bd20e724c56b6d1d04)
qtdeclarative/src/quick/scenegraph/coreapi/qsgtexture.cpp (08bfc40091f03f01e2866c88516e03dbd6342db5)

Public Types

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ AnisotropyLevel

◆ Filtering

◆ WrapMode

Constructor & Destructor Documentation

◆ QSGTexture() [1/2]

◆ ~QSGTexture()

◆ QSGTexture() [2/2]

Member Function Documentation

◆ anisotropyLevel()

◆ commitTextureOperations()

◆ comparisonKey()

◆ convertToNormalizedSourceRect()

◆ filtering()

◆ hasAlphaChannel()

◆ hasMipmaps()

◆ horizontalWrapMode()

◆ isAtlasTexture()

◆ mipmapFiltering()

◆ normalizedTextureSubRect()

◆ removedFromAtlas()

◆ rhiTexture()

◆ setAnisotropyLevel()

◆ setFiltering()

◆ setHorizontalWrapMode()

◆ setMipmapFiltering()

◆ setVerticalWrapMode()

◆ textureSize()

◆ verticalWrapMode()