QwtPlotGLCanvas(3)             Qwt User's Guide             QwtPlotGLCanvas(3)

NAME
       QwtPlotGLCanvas - An alternative canvas for a QwtPlot derived from
       QGLWidget.


SYNOPSIS
       #include <qwt_plot_glcanvas.h>

       Inherits QGLWidget, and QwtPlotAbstractGLCanvas.

   Public Slots
       void replot ()

   Public Member Functions
       QwtPlotGLCanvas (QwtPlot *=NULL)
           Constructor.
       QwtPlotGLCanvas (const QGLFormat &, QwtPlot *=NULL)
           Constructor.
       virtual ~QwtPlotGLCanvas ()
           Destructor.
       virtual Q_INVOKABLE void invalidateBackingStore () override
           Invalidate the internal backing store.
       Q_INVOKABLE QPainterPath borderPath (const QRect &) const
       virtual bool event (QEvent *) override

   Protected Member Functions
       virtual void paintEvent (QPaintEvent *) override
       virtual void initializeGL () override
           No operation - reserved for some potential use in the future.
       virtual void paintGL () override
           Paint the plot.
       virtual void resizeGL (int width, int height) override
           No operation - reserved for some potential use in the future.

   Additional Inherited Members

Detailed Description
       An alternative canvas for a QwtPlot derived from QGLWidget.

       QwtPlotGLCanvas implements the very basics to act as canvas inside of a
       QwtPlot widget. It might be extended to a full featured alternative to
       QwtPlotCanvas in a future version of Qwt.

       Even if QwtPlotGLCanvas is not derived from QFrame it imitates its API.
       When using style sheets it supports the box model - beside backgrounds
       with rounded borders.

       Since Qt 5.4 QOpenGLWidget is available, that is used by
       QwtPlotOpenGLCanvas.

       See also
           QwtPlot::setCanvas(), QwtPlotCanvas, QwtPlotOpenGLCanvas

       Note
           With Qt4 you might want to use the QPaintEngine::OpenGL paint
           engine ( see QGL::setPreferredPaintEngine() ). On a Linux test
           system QPaintEngine::OpenGL2 shows very basic problems like
           translated geometries.

           Another way for getting hardware accelerated graphics is using an
           OpenGL offscreen buffer ( QwtPlotCanvas::OpenGLBuffer ) with
           QwtPlotCanvas. Performance is worse, than rendering straight to a
           QGLWidget, but is usually better integrated into a desktop
           application.

       Definition at line 45 of file qwt_plot_glcanvas.h.

Constructor & Destructor Documentation
   QwtPlotGLCanvas::QwtPlotGLCanvas (QwtPlot * plot = NULL) [explicit]
       Constructor.

       Parameters
           plot Parent plot widget

       See also
           QwtPlot::setCanvas()

       Definition at line 56 of file qwt_plot_glcanvas.cpp.

   QwtPlotGLCanvas::QwtPlotGLCanvas (const QGLFormat & format, QwtPlot * plot
       = NULL) [explicit]
       Constructor.

       Parameters
           format OpenGL rendering options
           plot Parent plot widget

       See also
           QwtPlot::setCanvas()

       Definition at line 69 of file qwt_plot_glcanvas.cpp.

Member Function Documentation
   QPainterPath QwtPlotGLCanvas::borderPath (const QRect & rect) const
       Calculate the painter path for a styled or rounded border

       When the canvas has no styled background or rounded borders the painter
       path is empty.

       Parameters
           rect Bounding rectangle of the canvas

       Returns
           Painter path, that can be used for clipping

       Definition at line 157 of file qwt_plot_glcanvas.cpp.

   bool QwtPlotGLCanvas::event (QEvent * event) [override],  [virtual]
       Qt event handler for QEvent::PolishRequest and QEvent::StyleChange

       Parameters
           event Qt Event

       Returns
           See QGLWidget::event()

       Definition at line 110 of file qwt_plot_glcanvas.cpp.

   void QwtPlotGLCanvas::paintEvent (QPaintEvent * event) [override],
       [protected],  [virtual]
       Paint event

       Parameters
           event Paint event

       See also
           QwtPlot::drawCanvas()

       Definition at line 100 of file qwt_plot_glcanvas.cpp.

   void QwtPlotGLCanvas::replot () [slot]
       Invalidate the paint cache and repaint the canvas

       See also
           invalidatePaintCache()

       Definition at line 131 of file qwt_plot_glcanvas.cpp.


Author
       Generated automatically by Doxygen for Qwt User's Guide from the source
       code.

Version 6.2.0                   Sun Jul 18 2021             QwtPlotGLCanvas(3)