CopperSpice API  1.7.2
QOpenGLWindow Class Reference

The QOpenGLWindow class is a convenience subclass of QWindow to perform OpenGL painting. More...

Inheritance diagram for QOpenGLWindow:
QPaintDeviceWindow QWindow QPaintDevice QObject QSurface

Public Methods

 ~QOpenGLWindow ()
 
- Public Methods inherited from QPaintDeviceWindow
qreal devicePixelRatio () const
 
- Public Methods inherited from QWindow
 QWindow (QScreen *screen=nullptr)
 
 QWindow (QWindow *parent)
 
virtual ~QWindow ()
 
QSize baseSize () const
 
void create ()
 
QCursor cursor () const
 
void destroy ()
 
qreal devicePixelRatio () const
 
QString filePath () const
 
virtual QObjectfocusObject () const
 
QSurfaceFormat format () const override
 
QRect frameGeometry () const
 
QMargins frameMargins () const
 
QPoint framePosition () const
 
QRect geometry () const
 
QIcon icon () const
 
bool isActive () const
 
bool isAncestorOf (const QWindow *child, AncestorMode mode=IncludeTransients) const
 
bool isExposed () const
 
bool isModal () const
 
bool isTopLevel () const
 
QPoint mapFromGlobal (const QPoint &pos) const
 
QPoint mapToGlobal (const QPoint &pos) const
 
QRegion mask () const
 
QSize maximumSize () const
 
QSize minimumSize () const
 
QWindow * parent () const
 
QPoint position () const
 
QSurfaceFormat requestedFormat () const
 
void resize (const QSize &newSize)
 
void resize (int w, int h)
 
QScreenscreen () const
 
void setBaseSize (const QSize &size)
 
void setCursor (const QCursor &cursor)
 
void setFilePath (const QString &filePath)
 
void setFormat (const QSurfaceFormat &format)
 
void setFramePosition (const QPoint &point)
 
void setGeometry (const QRect &rect)
 
void setGeometry (int posx, int posy, int w, int h)
 
void setIcon (const QIcon &icon)
 
bool setKeyboardGrabEnabled (bool grab)
 
void setMask (const QRegion &region)
 
void setMaximumSize (const QSize &size)
 
void setMinimumSize (const QSize &size)
 
bool setMouseGrabEnabled (bool grab)
 
void setParent (QWindow *parent)
 
void setPosition (const QPoint &pt)
 
void setPosition (int posx, int posy)
 
void setScreen (QScreen *screen)
 
void setSizeIncrement (const QSize &size)
 
void setSurfaceType (SurfaceType surfaceType)
 
void setTransientParent (QWindow *parent)
 
void setWindowState (Qt::WindowState state)
 
QSize size () const override
 
QSize sizeIncrement () const
 
SurfaceType surfaceType () const override
 
QWindow * transientParent () const
 
Qt::WindowType type () const
 
Qt::WindowState windowState () const
 
WId winId () const
 
- Public Methods inherited from QObject
 QObject (QObject *parent=nullptr)
 
 ~QObject ()
 
bool blockSignals (bool block)
 
const QList< QObject * > & children () const
 
bool connect (const QObject *sender, const QString &signalMethod, const QString &location, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
bool connect (const QObject *sender, const QString &signalMethod, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
bool disconnect (const QObject *receiver, const QString &slotMethod=QString ()) const
 
bool disconnect (const QString &signalMethod, const QString &location, const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const
 
bool disconnect (const QString &signalMethod=QString (), const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const
 
void dumpObjectInfo ()
 
void dumpObjectTree ()
 
QList< QStringdynamicPropertyNames () const
 
virtual bool event (QEvent *event)
 
virtual bool eventFilter (QObject *watched, QEvent *event)
 
template<typename T >
findChild (const QString &childName=QString ()) const
 
template<class T >
QList< T > findChildren (const QRegularExpression &regExp, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
 
template<class T >
QList< T > findChildren (const QString &objName=QString (), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
 
bool inherits (const QString &className) const
 
void installEventFilter (QObject *filterObj)
 
bool isWidgetType () const
 
bool isWindowType () const
 
void killTimer (int id)
 
const QMetaObjectmetaObject () const
 
void moveToThread (QThread *targetThread)
 
QString objectName () const
 
QObject * parent () const
 
template<class T = QVariant>
property (const QString &name) const
 
void removeEventFilter (QObject *obj)
 
void setObjectName (const QString &name)
 
void setParent (QObject *parent)
 
bool setProperty (const QString &name, const QVariant &value)
 
bool signalsBlocked () const
 
int startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
 
QThreadthread () const
 
- Public Methods inherited from QSurface
virtual ~QSurface ()
 
virtual QSurfaceFormat format () const = 0
 
virtual QSize size () const = 0
 
bool supportsOpenGL () const
 
SurfaceClass surfaceClass () const
 
virtual QPlatformSurfacesurfaceHandle () const = 0
 
virtual SurfaceType surfaceType () const = 0
 
- Public Methods inherited from QPaintDevice
virtual ~QPaintDevice ()
 
int colorCount () const
 
int depth () const
 
int devicePixelRatio () const
 
qreal devicePixelRatioF () const
 
int height () const
 
int heightMM () const
 
int logicalDpiX () const
 
int logicalDpiY () const
 
bool paintingActive () const
 
int physicalDpiX () const
 
int physicalDpiY () const
 
int width () const
 
int widthMM () const
 

Protected Methods

int metric (PaintDeviceMetric metric) const override
 
void paintEvent (QPaintEvent *event) override
 
- Protected Methods inherited from QPaintDeviceWindow
int metric (PaintDeviceMetric metric) const override
 
- Protected Methods inherited from QWindow
bool event (QEvent *event) override
 
virtual void exposeEvent (QExposeEvent *event)
 
virtual void focusInEvent (QFocusEvent *event)
 
virtual void focusOutEvent (QFocusEvent *event)
 
virtual void hideEvent (QHideEvent *event)
 
virtual void keyPressEvent (QKeyEvent *event)
 
virtual void keyReleaseEvent (QKeyEvent *event)
 
virtual void mouseDoubleClickEvent (QMouseEvent *event)
 
virtual void mouseMoveEvent (QMouseEvent *event)
 
virtual void mousePressEvent (QMouseEvent *event)
 
virtual void mouseReleaseEvent (QMouseEvent *event)
 
virtual void moveEvent (QMoveEvent *event)
 
virtual bool nativeEvent (const QByteArray &eventType, void *message, long *result)
 
virtual void resizeEvent (QResizeEvent *event)
 
virtual void showEvent (QShowEvent *event)
 
virtual void tabletEvent (QTabletEvent *event)
 
virtual void wheelEvent (QWheelEvent *event)
 
- Protected Methods inherited from QObject
virtual void childEvent (QChildEvent *event)
 
virtual void connectNotify (const QMetaMethod &signalMethod) const
 
virtual void customEvent (QEvent *event)
 
virtual void disconnectNotify (const QMetaMethod &signalMethod) const
 
bool isSignalConnected (const QMetaMethod &signalMethod) const
 
int receivers (const QString &signal) const
 
QObject * sender () const
 
int senderSignalIndex () const
 
virtual void timerEvent (QTimerEvent *event)
 
- Protected Methods inherited from QSurface
 QSurface (SurfaceClass type)
 
- Protected Methods inherited from QPaintDevice
 QPaintDevice ()
 

Additional Inherited Members

- Public Types inherited from QWindow
enum  AncestorMode
 
enum  Visibility
 
- Public Types inherited from QSurface
enum  SurfaceClass
 
enum  SurfaceType
 
- Public Types inherited from QPaintDevice
enum  PaintDeviceMetric
 
- Public Signals inherited from QWindow
void focusObjectChanged (QObject *object)
 
void modalityChanged (Qt::WindowModality modality)
 
void screenChanged (QScreen *screen)
 
void windowStateChanged (Qt::WindowState windowState)
 
- Public Signals inherited from QObject
void destroyed (QObject *obj=nullptr)
 
void objectNameChanged (const QString &objectName)
 
- Public Slots inherited from QPaintDeviceWindow
void update ()
 
- Public Slots inherited from QWindow
void alert (int msec)
 
bool close ()
 
void hide ()
 
void lower ()
 
void raise ()
 
void requestActivate ()
 
void requestUpdate ()
 
void setMaximumWidth (int width)
 
void show ()
 
void showFullScreen ()
 
void showMaximized ()
 
void showMinimized ()
 
void showNormal ()
 
- Public Slots inherited from QObject
void deleteLater ()
 
- Static Public Methods inherited from QWindow
static QWindow * fromWinId (WId id)
 
- Static Public Methods inherited from QObject
static bool connect (const QObject *sender, const QMetaMethod &signalMethod, const QObject *receiver, const QMetaMethod &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
static bool connect (const QObject *sender, const QString &signalMethod, const QObject *receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection, const QString &location=QString ())
 
static bool connect (const QObject *sender, const QString &signalMethod, const QString &location, const QObject *receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool connect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, SlotReturn (SlotClass::*slotMethod)(SlotArgs...), Qt::ConnectionType type=Qt::AutoConnection)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool connect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, T slotLambda, Qt::ConnectionType type=Qt::AutoConnection)
 
static bool disconnect (const QObject *sender, const QMetaMethod &signalMethod, const QObject *receiver, const QMetaMethod &slotMethod)
 
static bool disconnect (const QObject *sender, const QString &signalMethod, const QObject *receiver, const QString &slotMethod)
 
static bool disconnect (const QObject *sender, const QString &signalMethod, const QString &location, const QObject *receiver, const QString &slotMethod)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, SlotReturn (SlotClass::*slotMethod)(SlotArgs...))
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver >
static bool disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, std::nullptr_t slotMethod=nullptr)
 
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, T slotMethod)
 
static QMetaObjectstaticMetaObject ()
 
static QString tr (const char *text, const char *comment=nullptr, std::optional< int > numArg=std::optional< int >())
 
- Properties inherited from QPaintDeviceWindow
 height
 
 width
 
- Properties inherited from QWindow
 active
 
 contentOrientation
 
 flags
 
 height
 
 maximumHeight
 
 maximumWidth
 
 minimumHeight
 
 minimumWidth
 
 modality
 
 opacity
 
 title
 
 visibility
 
 visible
 
 width
 
 x
 
 y
 
- Properties inherited from QObject
 objectName
 

Detailed Description

The QOpenGLWindow class is a convenience subclass of QWindow to perform OpenGL painting.

QOpenGLWindow is an enhanced QWindow that allows easily creating windows that perform OpenGL rendering using an API that is compatible with QOpenGLWidget and is similar to the legacy QGLWidget. Unlike QOpenGLWidget, QOpenGLWindow has no dependency on the widgets module and offers better performance.

A typical application will subclass QOpenGLWindow and reimplement the following virtual functions:

initializeGL()
OpenGL resource initialization
resizeGL()
Set up the transformation matrices and other window size dependent resources
paintGL()
Call OpenGL commands or draw using QPainter

To schedule a repaint, call the update() function. Note that this will not immediately result in a call to paintGL(). Calling update() multiple times in a row will not change the behavior in any way.

This is a slot so it can be connected to a QTimer::timeout() signal to perform animation. Note however that in the modern OpenGL world it is a much better choice to rely on synchronization to the vertical refresh rate of the display. See setSwapInterval() on a description of the swap interval. With a swap interval of 1, which is the case on most systems by default, the swapBuffers() call, that is executed internally by QOpenGLWindow after each repaint, will block and wait for vsync. This means that whenever the swap is done, an update can be scheduled again by calling update(), without relying on timers.

To request a specific configuration for the context, use setFormat() like for any other QWindow. This allows, among others, requesting a given OpenGL version and profile, or enabling depth and stencil buffers.

Unlike QWindow, QOpenGLWindow allows opening a painter on itself and perform QPainter-based drawing.

QOpenGLWindow supports multiple update behaviors. The default, NoPartialUpdate is equivalent to a regular, OpenGL-based QWindow or the legacy QGLWidget. In contrast, PartialUpdateBlit and PartialUpdateBlend are more in line with QOpenGLWidget's way of working, where there is always an extra, dedicated framebuffer object present. These modes allow, by sacrificing some performance, redrawing only a smaller area on each paint and having the rest of the content preserved from of the previous frame. This is useful for applications than render incrementally using QPainter, because this way they do not have to redraw the entire window content on each paintGL() call.

Similarly to QOpenGLWidget, QOpenGLWindow supports the Qt::AA_ShareOpenGLContexts attribute. When enabled, the OpenGL contexts of all QOpenGLWindow instances will share with each other. This allows accessing each other's shareable OpenGL resources.

For more information on graphics refer to Graphics View.

Note
Additional documentation pending.

Constructor & Destructor Documentation

QOpenGLWindow::~QOpenGLWindow ( )

Destroys the QOpenGLWindow instance, freeing its resources.

The OpenGLWindow's context is made current in the destructor, allowing for safe destruction of any child object that may need to release OpenGL resources belonging to the context provided by this window.

If you have objects wrapping OpenGL resources (such as QOpenGLBuffer, QOpenGLShaderProgram, etc.) as members of a QOpenGLWindow subclass, you may need to add a call to makeCurrent() in that subclass' destructor as well. Due to the rules of C++ object destruction, those objects will be destroyed before calling this function (but after that the destructor of the subclass has run), therefore making the OpenGL context current in this function happens too late for their safe disposal.

See also
makeCurrent()

Method Documentation

int QOpenGLWindow::metric ( PaintDeviceMetric  metric) const
overrideprotectedvirtual

Returns the metric information for the given paint device metric.

See also
PaintDeviceMetric

Reimplemented from QPaintDevice.

void QOpenGLWindow::paintEvent ( QPaintEvent event)
overrideprotectedvirtual

Handles paint events passed by the parameter event. The default implementation does nothing. Reimplement this function to perform painting. If necessary, the dirty area is retrievable from the event.

Reimplemented from QPaintDeviceWindow.