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QWaylandView Class

The QWaylandView class represents a view of a surface on an output. More...

Header: #include <QWaylandView>
qmake: QT += waylandcompositor
Inherits: QObject

This class is under development and is subject to change.

Properties

  • 1 property inherited from QObject

Public Functions

QWaylandView(QObject *renderObject = nullptr, QObject *parent = nullptr)
virtual ~QWaylandView()
virtual bool advance()
virtual void attach(const QWaylandBufferRef &ref, const QRegion &damage)
virtual QWaylandBufferRef currentBuffer()
virtual QRegion currentDamage()
virtual void discardCurrentBuffer()
bool discardFrontBuffers() const
bool isBufferLocked() const
QWaylandOutput *output() const
void setBufferLock(bool locked)
void setDiscardFrontBuffers(bool discard)
void setOutput(QWaylandOutput *output)
void setSurface(QWaylandSurface *surface)
QWaylandSurface *surface() const
  • 31 public functions inherited from QObject

Signals

void bufferLockChanged()
void discardFrontBuffersChanged()
void outputChanged()
void surfaceChanged()
void surfaceDestroyed()

Additional Inherited Members

  • 1 public slot inherited from QObject
  • 11 static public members inherited from QObject
  • 9 protected functions inherited from QObject

Detailed Description

The QWaylandView class represents a view of a surface on an output.

The QWaylandView corresponds to the presentation of a surface on a specific output, managing the buffers that contain the contents to be rendered. You can have several views into the same surface.

Property Documentation

bufferLock : bool

This property holds whether the view's buffer is currently locked. When the buffer is locked, advance() will not advance to the next buffer and returns false.

The default is false.

Access functions:

bool isBufferLocked() const
void setBufferLock(bool locked)

Notifier signal:

void bufferLockChanged()

discardFrontBuffers : bool

By default, the view locks the current buffer until advance() is called. Set this property to true to allow Qt to release the buffer when the throttling view is no longer using it.

Access functions:

bool discardFrontBuffers() const
void setDiscardFrontBuffers(bool discard)

Notifier signal:

void discardFrontBuffersChanged()

output : QWaylandOutput *

This property holds the output on which this view displays its surface.

Access functions:

QWaylandOutput *output() const
void setOutput(QWaylandOutput *output)

Notifier signal:

void outputChanged()

renderObject : QObject * const

surface : QWaylandSurface *

This property holds the surface viewed by this QWaylandView.

Access functions:

QWaylandSurface *surface() const
void setSurface(QWaylandSurface *surface)

Notifier signal:

void surfaceChanged()

Member Function Documentation

QWaylandView::QWaylandView(QObject *renderObject = nullptr, QObject *parent = nullptr)

Constructs a QWaylandView with the given renderObject and parent.

[virtual] QWaylandView::~QWaylandView()

Destroys the QWaylandView.

[virtual] bool QWaylandView::advance()

Sets the next buffer and damage region to current and returns true. If the buffer is locked or if no new buffer has been attached since the last call to advance(), the function returns false and does nothing.

If this view is set as the surface's throttling view, discardCurrentBuffer() is called on all views of the same surface for which the discardFrontBuffers property is set to true and the current buffer is the same as the throttling view's current buffer.

To enable clients to reuse existing buffers, enable the primary view to ensure that views running on a lower frequency will release their front buffer references. This design approach should avoid the situation where the lower frequency views throttle the frame rate of the client application.

[virtual] void QWaylandView::attach(const QWaylandBufferRef &ref, const QRegion &damage)

Attaches a new buffer ref and a damage region to this QWaylandView. These will become current on a subsequent call to the advance() method.

[virtual] QWaylandBufferRef QWaylandView::currentBuffer()

Returns a reference to this view's current buffer.

[virtual] QRegion QWaylandView::currentDamage()

Returns the current damage region of this view.

[virtual] void QWaylandView::discardCurrentBuffer()

Force the view to discard its current buffer, to allow it to be reused on the client side.

[signal] void QWaylandView::surfaceDestroyed()

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