A plot item, which displays any graphical shape that can be defined by a QPainterPath. More...

#include <qwt_plot_shapeitem.h>

Inheritance diagram for QwtPlotShapeItem:

Classes
class	PrivateData

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

enum	LegendMode { LegendShape , LegendColor }
	Legend modes. More...

Public Types inherited from QwtPlotItem
enum	RttiValues { Rtti_PlotItem = 0 , Rtti_PlotGrid , Rtti_PlotScale , Rtti_PlotLegend , Rtti_PlotMarker , Rtti_PlotCurve , Rtti_PlotSpectroCurve , Rtti_PlotIntervalCurve , Rtti_PlotHistogram , Rtti_PlotSpectrogram , Rtti_PlotGraphic , Rtti_PlotTradingCurve , Rtti_PlotBarChart , Rtti_PlotMultiBarChart , Rtti_PlotShape , Rtti_PlotTextLabel , Rtti_PlotZone , Rtti_PlotVectorField , Rtti_PlotArrowMarker , Rtti_PlotBoxChart , Rtti_PlotUserItem = 1000 }
	Runtime type information. More...

enum	ItemAttribute { Legend = 0x01 , AutoScale = 0x02 , Margins = 0x04 }
	Plot Item Attributes. More...

enum	ItemInterest { ScaleInterest = 0x01 , LegendInterest = 0x02 }
	Plot Item Interests. More...

enum	RenderHint { RenderAntialiased = 0x1 }
	Render hints. More...

Public Member Functions
	QwtPlotShapeItem (const QString &title=QString())
	Constructor.

	QwtPlotShapeItem (const QwtText &title)

void	setPaintAttribute (PaintAttribute, bool on=true)
	Specify an attribute how to draw the shape.

bool	testPaintAttribute (PaintAttribute) const
	Check if a paint attribute is enabled.

void	setLegendMode (LegendMode)
	Set the mode how to represent the item on the legend.

LegendMode	legendMode () const

void	setRect (const QRectF &)
	Set a path built from a rectangle.

void	setPolygon (const QPolygonF &)
	Set a path built from a polygon.

void	setShape (const QPainterPath &)
	Set the shape to be displayed.

QPainterPath	shape () const

void	setPen (const QColor &, qreal width=0.0, Qt::PenStyle=Qt::SolidLine)
	Build and assign a pen.

void	setPen (const QPen &)
	Assign a pen.

QPen	pen () const

void	setBrush (const QBrush &)
	Assign a brush.

QBrush	brush () const

void	setRenderTolerance (double)
	Set the tolerance for the weeding optimization.

double	renderTolerance () const

virtual QRectF	boundingRect () const override
	Bounding rectangle of the shape.

virtual void	draw (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect) const override
	Draw the shape item.

virtual QwtGraphic	legendIcon (int index, const QSizeF &) const override

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

Public Member Functions inherited from QwtPlotItem
	QwtPlotItem ()
	Default constructor.

	QwtPlotItem (const QString &title)
	Constructor with title as QString.

	QwtPlotItem (const QwtText &title)
	Constructor with title as QwtText.

virtual	~QwtPlotItem ()
	Destructor.

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

void	detach ()
	Detach the item from the plot.

QwtPlot *	plot () const
	Get the plot the item is attached to.

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

void	setTitle (const QwtText &title)
	Set the title using 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	setItemInterest (ItemInterest, bool on=true)
	Set an item interest.

bool	testItemInterest (ItemInterest) const
	Test an item interest.

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.

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

QSize	legendIconSize () const
	Get the legend icon size.

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
	Check if the item is visible.

void	setAxes (QwtAxisId xAxis, QwtAxisId yAxis)
	Set both axes.

void	setXAxis (QwtAxisId)
	Set the x-axis.

QwtAxisId	xAxis () const
	Get the x-axis.

void	setYAxis (QwtAxisId)
	Set the y-axis.

QwtAxisId	yAxis () const
	Get the y-axis.

virtual void	itemChanged ()
	Notify the plot that the item has changed.

virtual void	legendChanged ()
	Notify the item that the legend has changed.

virtual void	getCanvasMarginHint (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, double &left, double &top, double &right, double &bottom) const
	Get margin hints for the canvas.

virtual void	updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &)
	Update the item with new scale divisions.

virtual void	updateLegend (const QwtPlotItem *, const QList< QwtLegendData > &)
	Update the item with changes of the legend.

QRectF	scaleRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the scale rectangle.

QRectF	paintRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the paint rectangle.

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

Additional Inherited Members
Protected Member Functions inherited from QwtPlotItem
QwtGraphic	defaultIcon (const QBrush &, const QSizeF &) const
	Create a default icon.

Detailed Description

A plot item, which displays any graphical shape that can be defined by a QPainterPath.

QwtPlotShapeItem displays a shape composed from intersecting and uniting regions, rectangles, ellipses or irregular areas defined by lines, and curves. The shape is displayed with a pen and brush.

QwtPlotShapeItem offers a couple of optimizations like clipping or weeding. These algorithms need to convert the painter path into polygons that might be less performant for paths built from curves and ellipses.

More complex shapes, that can't be expressed by a QPainterPath can be displayed using QwtPlotGraphicItem.

See also: QwtPlotZone, QwtPlotGraphicItem

Member Enumeration Documentation

◆ LegendMode

enum QwtPlotShapeItem::LegendMode

Legend modes.

Mode how to display the item on the legend

Enumerator
LegendShape	Display a scaled down version of the shape.
LegendColor	Display a filled rectangle.

◆ PaintAttribute

enum QwtPlotShapeItem::PaintAttribute

Paint attributes.

Attributes to modify the drawing algorithm. The default disables all attributes

See also: setPaintAttribute(), testPaintAttribute()

Enumerator

ClipPolygons

Clip polygons before painting them. In situations, where points are far outside the visible area (f.e when zooming deep) this might be a substantial improvement for the painting performance

But polygon clipping will convert the painter path into polygons what might introduce a negative impact on the performance of paths composed from curves or ellipses.

Constructor & Destructor Documentation

◆ QwtPlotShapeItem()

QwtPlotShapeItem::QwtPlotShapeItem ( const QString & title = QString() )

explicit

Constructor.

Parameters

[in] title Title

Sets the following item attributes:

QwtPlotItem::AutoScale: true
QwtPlotItem::Legend: false

Constructor

Parameters

[in] title Title

Sets the following item attributes:

QwtPlotItem::AutoScale: true
QwtPlotItem::Legend: false

Destructor

Member Function Documentation

◆ boundingRect()

QRectF QwtPlotShapeItem::boundingRect ( ) const

overridevirtual

Bounding rectangle of the shape.

Reimplemented from QwtPlotItem.

◆ brush()

QBrush QwtPlotShapeItem::brush ( ) const

Returns: Brush used to fill the shape

See also: setBrush(), pen()

◆ draw()

void QwtPlotShapeItem::draw	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect
	)		const

overridevirtual

Draw the shape item.

Parameters

painter	Painter
xMap	X-Scale Map
yMap	Y-Scale Map
canvasRect	Contents rect of the plot canvas

Implements QwtPlotItem.

◆ legendIcon()

QwtGraphic QwtPlotShapeItem::legendIcon	(	int	index,
		const QSizeF &	size
	)		const

overridevirtual

Returns: A rectangle filled with the color of the brush ( or the pen )

Parameters

index	Index of the legend entry ( usually there is only one )
size	Icon size

See also: setLegendIconSize(), legendData()

Reimplemented from QwtPlotItem.

◆ legendMode()

QwtPlotShapeItem::LegendMode QwtPlotShapeItem::legendMode ( ) const

Returns: Mode how to represent the item on the legend

See also: legendMode()

◆ pen()

QPen QwtPlotShapeItem::pen ( ) const

Returns: Pen used to draw the outline of the shape

See also: setPen(), brush()

◆ renderTolerance()

double QwtPlotShapeItem::renderTolerance ( ) const

Returns: Tolerance for the weeding optimization

See also: setRenderTolerance()

◆ rtti()

int QwtPlotShapeItem::rtti ( ) const

overridevirtual

Get the runtime type information.

Returns: QwtPlotItem::Rtti_PlotShape

Reimplemented from QwtPlotItem.

◆ setBrush()

void QwtPlotShapeItem::setBrush ( const QBrush & brush )

Assign a brush.

The brush is used to fill the path

Parameters

brush Brush

See also: brush(), pen()

◆ setLegendMode()

void QwtPlotShapeItem::setLegendMode ( LegendMode mode )

Set the mode how to represent the item on the legend.

Parameters

[in] mode Mode

See also: legendMode()

◆ setPaintAttribute()

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

Specify an attribute how to draw the shape.

Parameters

[in]	attribute	Paint attribute
[in]	on	On/Off

See also: testPaintAttribute()

◆ setPen() [1/2]

void QwtPlotShapeItem::setPen	(	const QColor &	color,
		qreal	width = `0.0`,
		Qt::PenStyle	style = `Qt::SolidLine`
	)

Build and assign a pen.

In Qt5 the default pen width is 1.0 ( 0.0 in Qt4 ) what makes it non cosmetic ( see QPen::isCosmetic() ). This method has been introduced to hide this incompatibility.

Parameters

color	Pen color
width	Pen width
style	Pen style

See also: pen(), brush()

◆ setPen() [2/2]

void QwtPlotShapeItem::setPen ( const QPen & pen )

Assign a pen.

The pen is used to draw the outline of the shape

Parameters

pen Pen

See also: pen(), brush()

◆ setPolygon()

void QwtPlotShapeItem::setPolygon ( const QPolygonF & polygon )

Set a path built from a polygon.

Parameters

polygon Polygon

See also: setShape(), setRect(), shape()

◆ setRect()

void QwtPlotShapeItem::setRect ( const QRectF & rect )

Set a path built from a rectangle.

Parameters

rect Rectangle

See also: setShape(), setPolygon(), shape()

◆ setRenderTolerance()

void QwtPlotShapeItem::setRenderTolerance ( double tolerance )

Set the tolerance for the weeding optimization.

After translating the shape into target device coordinate ( usually widget geometries ) the painter path can be simplified by a point weeding algorithm ( Douglas-Peucker ).

For shapes built from curves and ellipses weeding might have the opposite effect because they have to be expanded to polygons.

Parameters

tolerance Accepted error when reducing the number of points A value <= 0.0 disables weeding.

See also: renderTolerance(), QwtWeedingCurveFitter

◆ setShape()

void QwtPlotShapeItem::setShape ( const QPainterPath & shape )

Set the shape to be displayed.

Parameters

shape Shape

See also: setShape(), shape()

◆ shape()

QPainterPath QwtPlotShapeItem::shape ( ) const

Returns: Shape to be displayed

See also: setShape()

◆ testPaintAttribute()

bool QwtPlotShapeItem::testPaintAttribute ( PaintAttribute attribute ) const

Check if a paint attribute is enabled.

Parameters

[in] attribute Paint attribute

Returns: True, when attribute is enabled

See also: setPaintAttribute()

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

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

Classes

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ LegendMode

◆ PaintAttribute

Constructor & Destructor Documentation

◆ QwtPlotShapeItem()

Member Function Documentation

◆ boundingRect()

◆ brush()

◆ draw()

◆ legendIcon()

◆ legendMode()

◆ pen()

◆ renderTolerance()

◆ rtti()

◆ setBrush()

◆ setLegendMode()

◆ setPaintAttribute()

◆ setPen() [1/2]

◆ setPen() [2/2]

◆ setPolygon()

◆ setRect()

◆ setRenderTolerance()

◆ setShape()

◆ shape()

◆ testPaintAttribute()