An item which draws scales and grid lines on a polar plot. More...

#include <qwt_polar_grid.h>

Inheritance diagram for QwtPolarGrid:

Classes
class	PrivateData

Public Types
enum	DisplayFlag { SmartOriginLabel = 1 , HideMaxRadiusLabel = 2 , ClipAxisBackground = 4 , SmartScaleDraw = 8 , ClipGridLines = 16 }
	Display flags to avoid conflicts when painting scales and grid lines. More...

enum	GridAttribute { AutoScaling = 0x01 }
	Grid attributes. More...

Public Types inherited from QwtPolarItem
enum	RttiValues { Rtti_PolarItem = 0 , Rtti_PolarGrid , Rtti_PolarMarker , Rtti_PolarCurve , Rtti_PolarSpectrogram , Rtti_PolarUserItem = 1000 }
	Runtime type information. More...

enum	ItemAttribute { Legend = 0x01 , AutoScale = 0x02 }
	Plot Item Attributes. More...

enum	RenderHint { RenderAntialiased = 0x01 }
	Render hints. More...

Public Member Functions
	QwtPolarGrid ()
	Constructor.

	~QwtPolarGrid () override
	Destructor.

virtual int	rtti () const override
	Get the runtime type information.

void	setDisplayFlag (DisplayFlag, bool on=true)
	Set a display flag.

bool	testDisplayFlag (DisplayFlag) const
	Test a display flag.

void	setGridAttribute (GridAttribute, bool on=true)
	Set a grid attribute.

bool	testGridAttribute (GridAttribute) const
	Test a grid attribute.

void	showGrid (int scaleId, bool show=true)
	Show/hide the grid for a scale.

bool	isGridVisible (int scaleId) const
	Check if the grid is visible for a scale.

void	showMinorGrid (int scaleId, bool show=true)
	Show/hide the minor grid for a scale.

bool	isMinorGridVisible (int scaleId) const
	Check if the minor grid is visible for a scale.

void	showAxis (int axisId, bool show=true)
	Show/hide an axis.

bool	isAxisVisible (int axisId) const
	Check if an axis is visible.

void	setPen (const QPen &p)
	Set the pen.

void	setFont (const QFont &)
	Set the font.

void	setMajorGridPen (const QPen &p)
	Set the major grid pen.

void	setMajorGridPen (int scaleId, const QPen &p)
	Set the major grid pen for a scale.

QPen	majorGridPen (int scaleId) const
	Get the major grid pen for a scale.

void	setMinorGridPen (const QPen &p)
	Set the minor grid pen.

void	setMinorGridPen (int scaleId, const QPen &p)
	Set the minor grid pen for a scale.

QPen	minorGridPen (int scaleId) const
	Get the minor grid pen for a scale.

void	setAxisPen (int axisId, const QPen &p)
	Set the axis pen.

QPen	axisPen (int axisId) const
	Get the axis pen.

void	setAxisFont (int axisId, const QFont &p)
	Set the axis font.

QFont	axisFont (int axisId) const
	Get the axis font.

void	setScaleDraw (int axisId, QwtScaleDraw *)
	Set the scale draw for an axis.

const QwtScaleDraw *	scaleDraw (int axisId) const
	Get the scale draw for an axis (const version)

QwtScaleDraw *	scaleDraw (int axisId)
	Get the scale draw for an axis.

void	setAzimuthScaleDraw (QwtRoundScaleDraw *)
	Set the azimuth scale draw.

const QwtRoundScaleDraw *	azimuthScaleDraw () const
	Get the azimuth scale draw (const version)

QwtRoundScaleDraw *	azimuthScaleDraw ()
	Get the azimuth scale draw.

virtual void	draw (QPainter *p, const QwtScaleMap &azimuthMap, const QwtScaleMap &radialMap, const QPointF &pole, double radius, const QRectF &rect) const override
	Draw the grid.

virtual void	updateScaleDiv (const QwtScaleDiv &azimuthMap, const QwtScaleDiv &radialMap, const QwtInterval &) override
	Update the scale division.

virtual int	marginHint () const override
	Get the margin hint.

Public Member Functions inherited from QwtPolarItem
	QwtPolarItem (const QwtText &title=QwtText())
	Constructor.

virtual	~QwtPolarItem ()
	Destructor.

void	attach (QwtPolarPlot *plot)
	Attach the item to a plot.

void	detach ()
	Detach the item from its plot.

QwtPolarPlot *	plot () const
	Get the attached plot.

void	setTitle (const QString &title)
	Set the title from a QString.

void	setTitle (const QwtText &title)
	Set the title from a QwtText.

const QwtText &	title () const
	Get the title.

void	setItemAttribute (ItemAttribute, bool on=true)
	Set an item attribute.

bool	testItemAttribute (ItemAttribute) const
	Test an item attribute.

void	setRenderHint (RenderHint, bool on=true)
	Set a render hint.

bool	testRenderHint (RenderHint) const
	Test a render hint.

void	setRenderThreadCount (uint numThreads)
	Set the number of render threads.

uint	renderThreadCount () const
	Get the number of render threads.

double	z () const
	Get the z value.

void	setZ (double z)
	Set the z value.

void	show ()
	Show the item.

void	hide ()
	Hide the item.

virtual void	setVisible (bool)
	Set the visibility.

bool	isVisible () const
	Get the visibility.

virtual void	itemChanged ()
	Update the item and trigger autoRefresh.

virtual void	legendChanged ()
	Update the legend.

virtual QwtInterval	boundingInterval (int scaleId) const
	Get the bounding interval for a scale.

void	setLegendIconSize (const QSize &)
	Set the legend icon size.

QSize	legendIconSize () const
	Get the legend icon size.

virtual QList< QwtLegendData >	legendData () const
	Get the legend data.

virtual QwtGraphic	legendIcon (int index, const QSizeF &) const
	Get the legend icon.

Protected Member Functions
void	drawRays (QPainter *, const QRectF &, const QPointF &pole, double radius, const QwtScaleMap &azimuthMap, const QList< double > &) const
	Draw the rays.

void	drawCircles (QPainter *, const QRectF &, const QPointF &pole, const QwtScaleMap &radialMap, const QList< double > &) const
	Draw the circles.

void	drawAxis (QPainter *, int axisId) const
	Draw an axis.

Detailed Description

An item which draws scales and grid lines on a polar plot.

The QwtPolarGrid class can be used to draw a coordinate grid. A coordinate grid consists of major and minor gridlines. The locations of the gridlines are determined by the azimuth and radial scale divisions.

QwtPolarGrid is also responsible for drawing the axis representing the scales. It is possible to display 4 radial and one azimuth axis.

Whenever the scale divisions of the plot widget changes the grid is synchronized by updateScaleDiv().

See also: QwtPolarPlot, QwtPolar::Axis

Member Enumeration Documentation

◆ DisplayFlag

enum QwtPolarGrid::DisplayFlag

Display flags to avoid conflicts when painting scales and grid lines.

The default setting enables all flags.

See also: setDisplayFlag(), testDisplayFlag()

Enumerator
SmartOriginLabel	Try to avoid situations, where the label of the origin is painted over another axis.
HideMaxRadiusLabel	Often the outermost tick of the radial scale is close to the canvas border. With HideMaxRadiusLabel enabled it is not painted.
ClipAxisBackground	The tick labels of the radial scales might be hard to read, when they are painted on top of the radial grid lines ( or on top of a curve/spectrogram ). When ClipAxisBackground the bounding rect of each label is added to the clip region.
SmartScaleDraw	Don't paint the backbone of the radial axes, when they are very close to a line of the azimuth grid.
ClipGridLines	All grid lines are clipped against the plot area before being painted. When the plot is zoomed in this will have an significant impact on the performance of the painting code.

◆ GridAttribute

enum QwtPolarGrid::GridAttribute

Grid attributes.

See also: setGridAttributes(), testGridAttributes()

Enumerator
AutoScaling	When AutoScaling is enabled, the radial axes will be adjusted to the interval, that is currently visible on the canvas plot.

Constructor & Destructor Documentation

◆ QwtPolarGrid()

QwtPolarGrid::QwtPolarGrid ( )

explicit

Constructor.

Enables major and disables minor grid lines. The azimuth and right radial axis are visible. All other axes are hidden. AutoScaling is enabled.

Destructor

Member Function Documentation

◆ axisFont()

QFont QwtPolarGrid::axisFont ( int axisId ) const

Get the axis font.

Get the font for the tick labels of a specific axis.

Parameters

axisId Axis id (QwtPolar::Axis)

Returns: Font for the axis

See also: setAxisFont()

◆ axisPen()

QPen QwtPolarGrid::axisPen ( int axisId ) const

Get the axis pen.

Get the pen for painting a specific axis.

Parameters

axisId Axis id (QwtPolar::Axis)

Returns: Pen for the axis

See also: setAxisPen()

◆ azimuthScaleDraw() [1/2]

QwtRoundScaleDraw * QwtPolarGrid::azimuthScaleDraw ( )

Get the azimuth scale draw.

Get the scale draw for the azimuth scale.

Returns: Scale draw for the azimuth scale

See also: setAzimuthScaleDraw(), scaleDraw()

◆ azimuthScaleDraw() [2/2]

const QwtRoundScaleDraw * QwtPolarGrid::azimuthScaleDraw ( ) const

Get the azimuth scale draw (const version)

Get the scale draw for the azimuth scale.

Returns: Scale draw for the azimuth scale

See also: setAzimuthScaleDraw(), scaleDraw()

◆ draw()

void QwtPolarGrid::draw	(	QPainter *	painter,
		const QwtScaleMap &	azimuthMap,
		const QwtScaleMap &	radialMap,
		const QPointF &	pole,
		double	radius,
		const QRectF &	canvasRect
	)		const

overridevirtual

Draw the grid.

Draw the grid and axes.

Parameters

painter	Painter
azimuthMap	Maps azimuth values to values related to 0.0, M_2PI
radialMap	Maps radius values into painter coordinates
pole	Position of the pole in painter coordinates
radius	Radius of the complete plot area in painter coordinates
canvasRect	Contents rect of the canvas in painter coordinates

Implements QwtPolarItem.

◆ drawAxis()

void QwtPolarGrid::drawAxis	(	QPainter *	painter,
		int	axisId
	)		const

protected

Draw an axis.

Paint an axis.

Parameters

painter	Painter
axisId	Axis id (QwtPolar::Axis)

◆ drawCircles()

void QwtPolarGrid::drawCircles	(	QPainter *	painter,
		const QRectF &	canvasRect,
		const QPointF &	pole,
		const QwtScaleMap &	radialMap,
		const QList< double > &	values
	)		const

protected

Draw the circles.

Draw circles.

Parameters

painter	Painter
canvasRect	Contents rect of the canvas in painter coordinates
pole	Position of the pole in painter coordinates
radialMap	Maps radius values into painter coordinates.
values	Radial values, indicating the distances from the pole

◆ drawRays()

void QwtPolarGrid::drawRays	(	QPainter *	painter,
		const QRectF &	canvasRect,
		const QPointF &	pole,
		double	radius,
		const QwtScaleMap &	azimuthMap,
		const QList< double > &	values
	)		const

protected

Draw the rays.

Draw lines from the pole.

Parameters

painter	Painter
canvasRect	Contents rect of the canvas in painter coordinates
pole	Position of the pole in painter coordinates
radius	Length of the lines in painter coordinates
azimuthMap	Maps azimuth values to values related to 0.0, M_2PI
values	Azimuth values, indicating the direction of the lines

◆ isAxisVisible()

bool QwtPolarGrid::isAxisVisible ( int axisId ) const

Check if an axis is visible.

Parameters

axisId Axis id (QwtPolar::Axis)

Returns: True if the axis is visible

See also: showAxis()

◆ isGridVisible()

bool QwtPolarGrid::isGridVisible ( int scaleId ) const

Check if the grid is visible for a scale.

Check if grid lines are visible for a scale.

Parameters

scaleId Scale id (QwtPolar::Scale)

Returns: True if grid lines are enabled

See also: QwtPolar::Scale, showGrid()

◆ isMinorGridVisible()

bool QwtPolarGrid::isMinorGridVisible ( int scaleId ) const

Check if the minor grid is visible for a scale.

Check if minor grid lines are visible for a scale.

Parameters

scaleId Scale id (QwtPolar::Scale)

Returns: True if minor grid lines are enabled

See also: showMinorGrid()

◆ majorGridPen()

QPen QwtPolarGrid::majorGridPen ( int scaleId ) const

Get the major grid pen for a scale.

Get the pen for painting the major grid lines of a specific scale.

Parameters

scaleId Scale id (QwtPolar::Scale)

Returns: Pen for major grid lines

See also: setMajorGridPen(), minorGridPen()

◆ marginHint()

int QwtPolarGrid::marginHint ( ) const

overridevirtual

Get the margin hint.

Returns: Number of pixels necessary to paint the azimuth scale

See also: QwtRoundScaleDraw::extent()

Reimplemented from QwtPolarItem.

◆ minorGridPen()

QPen QwtPolarGrid::minorGridPen ( int scaleId ) const

Get the minor grid pen for a scale.

Get the pen for painting the minor grid lines of a specific scale.

Parameters

scaleId Scale id (QwtPolar::Scale)

Returns: Pen for minor grid lines

See also: setMinorGridPen()

◆ rtti()

int QwtPolarGrid::rtti ( ) const

overridevirtual

Get the runtime type information.

Returns: QwtPlotItem::Rtti_PolarGrid

Reimplemented from QwtPolarItem.

◆ scaleDraw() [1/2]

QwtScaleDraw * QwtPolarGrid::scaleDraw ( int axisId )

Get the scale draw for an axis.

Get the scale draw of a specified axis.

Parameters

axisId Axis index (QwtPolar::AxisLeft <= axisId <= QwtPolar::AxisBottom)

Returns: Scale draw for the axis, or nullptr if axis is invalid

See also: setScaleDraw(), azimuthScaleDraw()

◆ scaleDraw() [2/2]

const QwtScaleDraw * QwtPolarGrid::scaleDraw ( int axisId ) const

Get the scale draw for an axis (const version)

Get the scale draw of a specified axis.

Parameters

axisId Axis index (QwtPolar::AxisLeft <= axisId <= QwtPolar::AxisBottom)

Returns: Scale draw for the axis, or nullptr if axis is invalid

See also: azimuthScaleDraw()

◆ setAxisFont()

void QwtPolarGrid::setAxisFont	(	int	axisId,
		const QFont &	font
	)

Set the axis font.

Assign a font for the tick labels of a specific axis.

Parameters

axisId	Axis id (QwtPolar::Axis)
font	New font

See also: axisFont()

◆ setAxisPen()

void QwtPolarGrid::setAxisPen	(	int	axisId,
		const QPen &	pen
	)

Set the axis pen.

Assign a pen for painting an axis.

Parameters

axisId	Axis id (QwtPolar::Axis)
pen	Pen for the axis

See also: axisPen()

◆ setAzimuthScaleDraw()

void QwtPolarGrid::setAzimuthScaleDraw ( QwtRoundScaleDraw * scaleDraw )

Set the azimuth scale draw.

Set a scale draw for the azimuth scale.

Parameters

scaleDraw Object responsible for drawing scales (ownership is transferred)

See also: azimuthScaleDraw(), setScaleDraw()

◆ setDisplayFlag()

void QwtPolarGrid::setDisplayFlag	(	DisplayFlag	flag,
		bool	on = `true`
	)

Set a display flag.

Change the display flags.

Parameters

flag	Display flag to modify
on	True to enable, false to disable

See also: DisplayFlag

◆ setFont()

void QwtPolarGrid::setFont ( const QFont & font )

Set the font.

Assign a font for all scale tick labels.

Parameters

font	Font for all scale tick labels

See also: setAxisFont()

◆ setGridAttribute()

void QwtPolarGrid::setGridAttribute	(	GridAttribute	attribute,
		bool	on = `true`
	)

Set a grid attribute.

Specify an attribute for the grid.

Parameters

attribute	Grid attribute to set
on	True to enable, false to disable

See also: GridAttribute, testGridAttribute(), updateScaleDiv(), QwtPolarPlot::zoom(), QwtPolarPlot::scaleDiv()

◆ setMajorGridPen() [1/2]

void QwtPolarGrid::setMajorGridPen ( const QPen & pen )

Set the major grid pen.

Assign a pen for the major grid lines.

Parameters

pen	Pen for major grid lines

See also: setPen(), setMinorGridPen(), majorGridPen()

◆ setMajorGridPen() [2/2]

void QwtPolarGrid::setMajorGridPen	(	int	scaleId,
		const QPen &	pen
	)

Set the major grid pen for a scale.

Assign a pen for the major grid lines of a specific scale.

Parameters

scaleId	Scale id (QwtPolar::Scale)
pen	Pen for major grid lines

See also: setPen(), setMinorGridPen(), majorGridPen()

◆ setMinorGridPen() [1/2]

void QwtPolarGrid::setMinorGridPen ( const QPen & pen )

Set the minor grid pen.

Assign a pen for the minor grid lines.

Parameters

pen	Pen for minor grid lines

See also: setPen(), setMajorGridPen(), minorGridPen()

◆ setMinorGridPen() [2/2]

void QwtPolarGrid::setMinorGridPen	(	int	scaleId,
		const QPen &	pen
	)

Set the minor grid pen for a scale.

Assign a pen for the minor grid lines of a specific scale.

Parameters

scaleId	Scale id (QwtPolar::Scale)
pen	Pen for minor grid lines

See also: setPen(), setMajorGridPen(), minorGridPen()

◆ setPen()

void QwtPolarGrid::setPen ( const QPen & pen )

Set the pen.

Assign a pen for all axes and grid lines.

Parameters

pen	Pen for all axes and grid lines

See also: setMajorGridPen(), setMinorGridPen(), setAxisPen()

◆ setScaleDraw()

void QwtPolarGrid::setScaleDraw	(	int	axisId,
		QwtScaleDraw *	scaleDraw
	)

Set the scale draw for an axis.

Set a scale draw for a specified axis.

Parameters

axisId	Axis index (QwtPolar::AxisLeft <= axisId <= QwtPolar::AxisBottom)
scaleDraw	Object responsible for drawing scales (ownership is transferred)

See also: scaleDraw(), setAzimuthScaleDraw()

◆ showAxis()

void QwtPolarGrid::showAxis	(	int	axisId,
		bool	show = `true`
	)

Show/hide an axis.

Parameters

axisId	Axis id (QwtPolar::Axis)
show	True to show, false to hide

See also: isAxisVisible()

◆ showGrid()

void QwtPolarGrid::showGrid	(	int	scaleId,
		bool	show = `true`
	)

Show/hide the grid for a scale.

Show/hide grid lines for a scale.

Parameters

scaleId	Scale id (QwtPolar::Scale)
show	True to show, false to hide

See also: QwtPolar::Scale, isGridVisible()

◆ showMinorGrid()

void QwtPolarGrid::showMinorGrid	(	int	scaleId,
		bool	show = `true`
	)

Show/hide the minor grid for a scale.

Show/hide minor grid lines for a scale.

Parameters

scaleId	Scale id (QwtPolar::Scale)
show	True to show, false to hide

To display minor grid lines, showGrid() needs to be enabled too.

See also: showGrid()

◆ testDisplayFlag()

bool QwtPolarGrid::testDisplayFlag ( DisplayFlag flag ) const

Test a display flag.

Parameters

flag	Display flag to test

Returns: True if flag is enabled

See also: DisplayFlag

◆ testGridAttribute()

bool QwtPolarGrid::testGridAttribute ( GridAttribute attribute ) const

Test a grid attribute.

Parameters

attribute Grid attribute to test

Returns: True if attribute is enabled

See also: GridAttribute, setGridAttribute()

◆ updateScaleDiv()

void QwtPolarGrid::updateScaleDiv	(	const QwtScaleDiv &	azimuthScaleDiv,
		const QwtScaleDiv &	radialScaleDiv,
		const QwtInterval &	interval
	)

overridevirtual

Update the scale division.

Update the item to changes of the axes scale division.

Parameters

azimuthScaleDiv	Scale division of the azimuth-scale
radialScaleDiv	Scale division of the radius-axis
interval	The interval of the radius-axis that is visible on the canvas

If AutoScaling is enabled the radial scale is calculated from the interval, otherwise the scales are adopted to the plot scales.

See also: QwtPolarPlot::setGridAttributes()

Reimplemented from QwtPolarItem.

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

/home/runner/work/QWT/QWT/src/plot/qwt_polar_grid.h
/home/runner/work/QWT/QWT/src/plot/qwt_polar_grid.cpp

Classes

Public Types

Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

◆ DisplayFlag

◆ GridAttribute

Constructor & Destructor Documentation

◆ QwtPolarGrid()

Member Function Documentation

◆ axisFont()

◆ axisPen()

◆ azimuthScaleDraw() [1/2]

◆ azimuthScaleDraw() [2/2]

◆ draw()

◆ drawAxis()

◆ drawCircles()

◆ drawRays()

◆ isAxisVisible()

◆ isGridVisible()

◆ isMinorGridVisible()

◆ majorGridPen()

◆ marginHint()

◆ minorGridPen()

◆ rtti()

◆ scaleDraw() [1/2]

◆ scaleDraw() [2/2]

◆ setAxisFont()

◆ setAxisPen()

◆ setAzimuthScaleDraw()

◆ setDisplayFlag()

◆ setFont()

◆ setGridAttribute()

◆ setMajorGridPen() [1/2]

◆ setMajorGridPen() [2/2]

◆ setMinorGridPen() [1/2]

◆ setMinorGridPen() [2/2]

◆ setPen()

◆ setScaleDraw()

◆ showAxis()

◆ showGrid()

◆ showMinorGrid()

◆ testDisplayFlag()

◆ testGridAttribute()

◆ updateScaleDiv()