QwtPolarCanvas Class Reference

Canvas of a QwtPolarPlot. More...

#include <qwt_polar_canvas.h>

Inheritance diagram for QwtPolarCanvas:

Classes
class	PrivateData

Public Types
enum	PaintAttribute { BackingStore = 0x01 }
	Paint attributes. More...

Public Member Functions
	QwtPolarCanvas (QwtPolarPlot *)
	Constructor.
	~QwtPolarCanvas () override
	Destructor.
QwtPolarPlot *	plot ()
	Get the plot.
const QwtPolarPlot *	plot () const
	Get the plot (const version)
void	setPaintAttribute (PaintAttribute, bool on=true)
	Set a paint attribute.
bool	testPaintAttribute (PaintAttribute) const
	Test a paint attribute.
const QPixmap *	backingStore () const
	Get the backing store.
void	invalidateBackingStore ()
	Invalidate the backing store.
QwtPointPolar	invTransform (const QPoint &) const
	Inverse transform from widget coordinates to polar coordinates.
QPoint	transform (const QwtPointPolar &) const
	Transform from polar coordinates to widget coordinates.

Protected Member Functions
virtual void	paintEvent (QPaintEvent *) override
	Handle paint events.
virtual void	resizeEvent (QResizeEvent *) override
	Handle resize events.

Detailed Description

Canvas of a QwtPolarPlot.

The canvas is the widget, where all polar items are painted to.

Note

In opposite to QwtPlot all axes are painted on the canvas.

See also

QwtPolarPlot

Member Enumeration Documentation

PaintAttribute

enum QwtPolarCanvas::PaintAttribute

Paint attributes.

The default setting enables BackingStore

See also

setPaintAttribute(), testPaintAttribute(), backingStore()

Enumerator
BackingStore	Paint double buffered and reuse the content of the pixmap buffer for some spontaneous repaints that happen when a plot gets unhidden, deiconified or changes the focus.

Constructor & Destructor Documentation

QwtPolarCanvas()

QwtPolarCanvas::QwtPolarCanvas ( QwtPolarPlot *  plot )

explicit

Constructor.

Parameters

plot	Parent polar plot widget

Destructor

Member Function Documentation

backingStore()

const QPixmap * QwtPolarCanvas::backingStore

(

)

const

Get the backing store.

Get the backing store pixmap.

Returns

Backing store pixmap, might be null if not enabled

See also

setPaintAttribute(), invalidateBackingStore()

invalidateBackingStore()

void QwtPolarCanvas::invalidateBackingStore

(

)

Invalidate the backing store.

Invalidate the internal backing store.

Clears the backing store pixmap, forcing a full repaint on the next paint event.

See also

backingStore()

invTransform()

QwtPointPolar QwtPolarCanvas::invTransform

(

const QPoint &

pos

)

const

Inverse transform from widget coordinates to polar coordinates.

Translate a point from widget coordinates to polar coordinates.

Parameters

pos	Point in widget coordinates of the plot canvas

Returns

Point in polar coordinates

See also

transform()

paintEvent()

void QwtPolarCanvas::paintEvent ( QPaintEvent *  event )

overrideprotectedvirtual

Handle paint events.

Paint event.

Parameters

event

Paint event

plot() [1/2]

QwtPolarPlot * QwtPolarCanvas::plot

(

)

Get the plot.

Get the parent plot widget.

Returns

Parent polar plot widget

plot() [2/2]

const QwtPolarPlot * QwtPolarCanvas::plot

(

)

const

Get the plot (const version)

Get the parent plot widget (const version)

Returns

Parent polar plot widget

resizeEvent()

void QwtPolarCanvas::resizeEvent ( QResizeEvent *  event )

overrideprotectedvirtual

Handle resize events.

Resize event.

Parameters

event

Resize event

setPaintAttribute()

void QwtPolarCanvas::setPaintAttribute	(	PaintAttribute	attribute,
		bool	on = true
	)

Set a paint attribute.

Change the paint attributes.

Parameters

attribute	Paint attribute to modify
on	True to enable, false to disable

The default setting enables BackingStore.

See also

testPaintAttribute(), backingStore()

testPaintAttribute()

bool QwtPolarCanvas::testPaintAttribute

(

PaintAttribute

attribute

)

const

Test a paint attribute.

Test whether a paint attribute is enabled.

Parameters

attribute

Paint attribute to test

Returns

True if the attribute is enabled

See also

setPaintAttribute()

transform()

QPoint QwtPolarCanvas::transform

(

const QwtPointPolar &

polarPos

)

const

Transform from polar coordinates to widget coordinates.

Translate a point from polar coordinates to widget coordinates.

Parameters

polarPos

Point in polar coordinates

Returns

Point in widget coordinates

See also

invTransform()

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

• /home/runner/work/QWT/QWT/src/plot/qwt_polar_canvas.h
• /home/runner/work/QWT/QWT/src/plot/qwt_polar_canvas.cpp