A plot item, that represents a series of points. More...

#include <qwt_plot_curve.h>

Inheritance diagram for QwtPlotCurve:

Public Types
enum	CurveStyle { NoCurve = -1 , Lines , Sticks , Steps , Dots , UserCurve = 100 }

enum	CurveAttribute { Inverted = 0x01 , Fitted = 0x02 }

enum	LegendAttribute { LegendNoAttribute = 0x00 , LegendShowLine = 0x01 , LegendShowSymbol = 0x02 , LegendShowBrush = 0x04 }

enum	PaintAttribute { ClipPolygons = 0x01 , FilterPoints = 0x02 , MinimizeMemory = 0x04 , ImageBuffer = 0x08 , FilterPointsAggressive = 0x10 }

typedef QFlags< CurveAttribute >	CurveAttributes

typedef QFlags< LegendAttribute >	LegendAttributes

typedef QFlags< PaintAttribute >	PaintAttributes

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_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...

typedef QFlags< ItemAttribute >	ItemAttributes

typedef QFlags< ItemInterest >	ItemInterests

typedef QFlags< RenderHint >	RenderHints

Public Member Functions
	QwtPlotCurve (const QString &title=QString())

	QwtPlotCurve (const QwtText &title)

virtual	~QwtPlotCurve ()
	Destructor.

virtual int	rtti () const override

void	setPaintAttribute (PaintAttribute, bool on=true)

bool	testPaintAttribute (PaintAttribute) const

void	setLegendAttribute (LegendAttribute, bool on=true)

bool	testLegendAttribute (LegendAttribute) const

void	setLegendAttributes (LegendAttributes)

LegendAttributes	legendAttributes () const

void	setRawSamples (const double xData, const double yData, int size)
	Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve.

void	setRawSamples (const float xData, const float yData, int size)
	Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve.

void	setRawSamples (const double *yData, int size)
	Initialize the data by pointing to a memory block which is not managed by QwtPlotCurve.

void	setRawSamples (const float *yData, int size)
	Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve.

void	setSamples (const double xData, const double yData, int size)

void	setSamples (const float xData, const float yData, int size)

void	setSamples (const double *yData, int size)

void	setSamples (const float *yData, int size)

void	setSamples (const QVector< double > &yData)

void	setSamples (const QVector< float > &yData)

void	setSamples (const QVector< double > &xData, const QVector< double > &yData)
	Initialize data with x- and y-arrays (explicitly shared)

void	setSamples (const QVector< float > &xData, const QVector< float > &yData)
	Initialize data with x- and y-arrays (explicitly shared)

void	setSamples (const QVector< QPointF > &)

void	setSamples (QwtSeriesData< QPointF > *)

virtual int	closestPoint (const QPointF &pos, double *dist=NULL) const

virtual int	adjacentPoint (Qt::Orientation orientation, qreal value) const

qreal	interpolatedValueAt (Qt::Orientation, double) const

double	minXValue () const
	boundingRect().left()

double	maxXValue () const
	boundingRect().right()

double	minYValue () const
	boundingRect().top()

double	maxYValue () const
	boundingRect().bottom()

void	setCurveAttribute (CurveAttribute, bool on=true)

bool	testCurveAttribute (CurveAttribute) const

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

void	setPen (const QPen &)

const QPen &	pen () const

void	setBrush (const QBrush &)
	Assign a brush.

const QBrush &	brush () const

void	setBaseline (double)
	Set the value of the baseline.

double	baseline () const

void	setStyle (CurveStyle style)

CurveStyle	style () const

void	setSymbol (QwtSymbol *)
	Assign a symbol.

const QwtSymbol *	symbol () const

void	setCurveFitter (QwtCurveFitter *)

QwtCurveFitter *	curveFitter () const

virtual void	drawSeries (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const override

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

Public Member Functions inherited from QwtPlotSeriesItem
	QwtPlotSeriesItem (const QString &title=QString())

	QwtPlotSeriesItem (const QwtText &title)

virtual	~QwtPlotSeriesItem ()
	Destructor.

void	setOrientation (Qt::Orientation)

Qt::Orientation	orientation () const

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

virtual QRectF	boundingRect () const override

virtual void	updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &) override
	Update the item to changes of the axes scale division.

Public Member Functions inherited from QwtPlotItem
	QwtPlotItem ()

	QwtPlotItem (const QString &title)

	QwtPlotItem (const QwtText &title)

virtual	~QwtPlotItem ()
	Destroy the QwtPlotItem.

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

void	detach ()
	This method detaches a QwtPlotItem from any QwtPlot it has been associated with.

QwtPlot *	plot () const
	Return attached plot.

void	setTitle (const QString &title)

void	setTitle (const QwtText &title)

const QwtText &	title () const

void	setItemAttribute (ItemAttribute, bool on=true)

bool	testItemAttribute (ItemAttribute) const

void	setItemInterest (ItemInterest, bool on=true)

bool	testItemInterest (ItemInterest) const

void	setRenderHint (RenderHint, bool on=true)

bool	testRenderHint (RenderHint) const

void	setRenderThreadCount (uint numThreads)

uint	renderThreadCount () const

void	setLegendIconSize (const QSize &)

QSize	legendIconSize () const

double	z () const

void	setZ (double z)
	Set the z value.

void	show ()
	Show the item.

void	hide ()
	Hide the item.

virtual void	setVisible (bool)

bool	isVisible () const

void	setAxes (QwtAxisId xAxis, QwtAxisId yAxis)

void	setXAxis (QwtAxisId)

QwtAxisId	xAxis () const
	Return xAxis.

void	setYAxis (QwtAxisId)

QwtAxisId	yAxis () const
	Return yAxis.

virtual void	itemChanged ()

virtual void	legendChanged ()

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

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

QRectF	scaleRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the bounding scale rectangle of 2 maps.

QRectF	paintRect (const QwtScaleMap &, const QwtScaleMap &) const
	Calculate the bounding paint rectangle of 2 maps.

virtual QList< QwtLegendData >	legendData () const
	Return all information, that is needed to represent the item on the legend.

Public Member Functions inherited from QwtAbstractSeriesStore
virtual	~QwtAbstractSeriesStore ()
	Destructor.

Public Member Functions inherited from QwtSeriesStore< QPointF >
	QwtSeriesStore ()
	Constructor The store contains no series.

	~QwtSeriesStore ()
	Destructor.

void	setData (QwtSeriesData< QPointF > *series)

QwtSeriesData< QPointF > *	data ()

const QwtSeriesData< QPointF > *	data () const

QPointF	sample (int index) const

virtual size_t	dataSize () const override

virtual QRectF	dataRect () const override

virtual void	setRectOfInterest (const QRectF &rect) override

QwtSeriesData< QPointF > *	swapData (QwtSeriesData< QPointF > *series)

Protected Member Functions
void	init ()
	Initialize internal members.

virtual void	drawCurve (QPainter *, int style, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const
	Draw the line part (without symbols) of a curve interval.

virtual void	drawSymbols (QPainter *, const QwtSymbol &, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const

virtual void	drawLines (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const
	Draw lines.

virtual void	drawSticks (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const

virtual void	drawDots (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const

virtual void	drawSteps (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const

virtual void	fillCurve (QPainter *, const QwtScaleMap &, const QwtScaleMap &, const QRectF &canvasRect, QPolygonF &) const

void	closePolyline (QPainter *, const QwtScaleMap &, const QwtScaleMap &, QPolygonF &) const
	Complete a polygon to be a closed polygon including the area between the original polygon and the baseline.

Protected Member Functions inherited from QwtPlotSeriesItem
virtual void	dataChanged () override
	dataChanged() indicates, that the series has been changed.

Protected Member Functions inherited from QwtPlotItem
QwtGraphic	defaultIcon (const QBrush &, const QSizeF &) const
	Return a default icon from a brush.

Detailed Description

A plot item, that represents a series of points.

A curve is the representation of a series of points in the x-y plane. It supports different display styles, interpolation ( f.e. spline ) and symbols.

Usage

a) Assign curve properties: When a curve is created, it is configured to draw black solid lines with in QwtPlotCurve::Lines style and no symbols. You can change this by calling setPen(), setStyle() and setSymbol().
b) Connect/Assign data.: QwtPlotCurve gets its points using a QwtSeriesData object offering a bridge to the real storage of the points ( like QAbstractItemModel ). There are several convenience classes derived from QwtSeriesData, that also store the points inside ( like QStandardItemModel ). QwtPlotCurve also offers a couple of variations of setSamples(), that build QwtSeriesData objects from arrays internally.
c) Attach the curve to a plot: See QwtPlotItem::attach()

Example:: see examples/bode

See also: QwtPointSeriesData, QwtSymbol, QwtScaleMap

Definition at line 56 of file qwt_plot_curve.h.

Member Typedef Documentation

◆ CurveAttributes

typedef QFlags<CurveAttribute > QwtPlotCurve::CurveAttributes

An ORed combination of CurveAttribute values.

Definition at line 133 of file qwt_plot_curve.h.

◆ LegendAttributes

typedef QFlags<LegendAttribute > QwtPlotCurve::LegendAttributes

An ORed combination of LegendAttribute values.

Definition at line 168 of file qwt_plot_curve.h.

◆ PaintAttributes

typedef QFlags<PaintAttribute > QwtPlotCurve::PaintAttributes

An ORed combination of PaintAttribute values.

Definition at line 234 of file qwt_plot_curve.h.

Member Enumeration Documentation

◆ CurveAttribute

enum QwtPlotCurve::CurveAttribute

Attribute for drawing the curve

See also: setCurveAttribute(), testCurveAttribute(), curveFitter()

Enumerator

Inverted

For QwtPlotCurve::Steps only. Draws a step function from the right to the left.

Fitted

Only in combination with QwtPlotCurve::Lines A QwtCurveFitter tries to interpolate/smooth the curve, before it is painted.

Note: Curve fitting requires temporary memory for calculating coefficients and additional points. If painting in QwtPlotCurve::Fitted mode is slow it might be better to fit the points, before they are passed to QwtPlotCurve.

Definition at line 112 of file qwt_plot_curve.h.

◆ CurveStyle

enum QwtPlotCurve::CurveStyle

Curve styles.

See also: setStyle(), style()

Enumerator
NoCurve	Don't draw a curve. Note: This doesn't affect the symbols.
Lines	Connect the points with straight lines. The lines might be interpolated depending on the 'Fitted' attribute. Curve fitting can be configured using setCurveFitter().
Sticks	Draw vertical or horizontal sticks ( depending on the orientation() ) from a baseline which is defined by setBaseline().
Steps	Connect the points with a step function. The step function is drawn from the left to the right or vice versa, depending on the QwtPlotCurve::Inverted attribute.
Dots	Draw dots at the locations of the data points. Note: This is different from a dotted line (see setPen()), and faster as a curve in QwtPlotCurve::NoStyle style and a symbol painting a point.
UserCurve	Styles >= QwtPlotCurve::UserCurve are reserved for derived classes of QwtPlotCurve that overload drawCurve() with additional application specific curve types.

Definition at line 65 of file qwt_plot_curve.h.

◆ LegendAttribute

enum QwtPlotCurve::LegendAttribute

Attributes how to represent the curve on the legend

See also: setLegendAttribute(), testLegendAttribute(), QwtPlotItem::legendData(), legendIcon()

Enumerator
LegendNoAttribute	QwtPlotCurve tries to find a color representing the curve and paints a rectangle with it.
LegendShowLine	If the style() is not QwtPlotCurve::NoCurve a line is painted with the curve pen().
LegendShowSymbol	If the curve has a valid symbol it is painted.
LegendShowBrush	If the curve has a brush a rectangle filled with the curve brush() is painted.

Definition at line 142 of file qwt_plot_curve.h.

◆ PaintAttribute

enum QwtPlotCurve::PaintAttribute

Attributes to modify the drawing algorithm. The default setting enables ClipPolygons | FilterPoints

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
FilterPoints	Tries to reduce the data that has to be painted, by sorting out duplicates, or paintings outside the visible area. Might have a notable impact on curves with many close points. Only a couple of very basic filtering algorithms are implemented.
MinimizeMemory	Minimize memory usage that is temporarily needed for the translated points, before they get painted. This might slow down the performance of painting
ImageBuffer	Render the points to a temporary image and paint the image. This is a very special optimization for Dots style, when having a huge amount of points. With a reasonable number of points QPainter::drawPoints() will be faster.
FilterPointsAggressive	More aggressive point filtering trying to filter out intermediate points, accepting minor visual differences. Has only an effect, when drawing the curve to a paint device in integer coordinates ( f.e. all widgets on screen ) using the fact, that consecutive points are often mapped to the same x or y coordinate. Each chunk of samples mapped to the same coordinate can be reduced to 4 points ( first, min, max last ). In the worst case the polygon to be rendered will be 4 times the width of the plot canvas. The algorithm is very fast and effective for huge datasets, and can be used inside a replot cycle. Note Implemented for QwtPlotCurve::Lines only As this algo replaces many small lines by a long one a nasty bug of the raster paint engine ( Qt 4.8, Qt 5.1 - 5.3 ) becomes more dominant. For these versions the bug can be worked around by enabling the QwtPainter::polylineSplitting() mode.

Definition at line 176 of file qwt_plot_curve.h.

Constructor & Destructor Documentation

◆ QwtPlotCurve() [1/2]

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

explicit

Constructor

Parameters

title Title of the curve

Definition at line 123 of file qwt_plot_curve.cpp.

◆ QwtPlotCurve() [2/2]

QwtPlotCurve::QwtPlotCurve ( const QwtText & title )

explicit

Constructor

Parameters

title Title of the curve

Definition at line 113 of file qwt_plot_curve.cpp.

◆ ~QwtPlotCurve()

QwtPlotCurve::~QwtPlotCurve ( )

virtual

Destructor.

Definition at line 130 of file qwt_plot_curve.cpp.

Member Function Documentation

◆ adjacentPoint()

int QwtPlotCurve::adjacentPoint	(	Qt::Orientation	orientation,
		qreal	value ) const

virtual

Find the curve point with the smallest coordinate larger than a specific value The coordinates have to be monotonic in direction of the orientation.

Parameters

orientation	Qt::Horizontal corresponds to x, Qt::Vertical to y coordinates
value	x or y coordinate, depending on the orientation

Returns: Index of the curve point with the smalles coordinate above value or -1 if there is none.

Note: The implementation uses a binary search algorithm and requires the points being ordered in direction of the orientation.

See also: qwtUpperSampleIndex()

Definition at line 1108 of file qwt_plot_curve.cpp.

◆ baseline()

double QwtPlotCurve::baseline ( ) const

Returns: Value of the baseline

See also: setBaseline()

Definition at line 1038 of file qwt_plot_curve.cpp.

◆ brush()

const QBrush & QwtPlotCurve::brush ( ) const

Returns: Brush used to fill the area between lines and the baseline

See also: setBrush(), setBaseline(), baseline()

Definition at line 366 of file qwt_plot_curve.cpp.

◆ closePolyline()

void QwtPlotCurve::closePolyline	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		QPolygonF &	polygon ) const

protected

Complete a polygon to be a closed polygon including the area between the original polygon and the baseline.

Parameters

painter	Painter
xMap	X map
yMap	Y map
polygon	Polygon to be completed

Definition at line 932 of file qwt_plot_curve.cpp.

◆ closestPoint()

int QwtPlotCurve::closestPoint	(	const QPointF &	pos,
		double *	dist = NULL ) const

virtual

Find the closest curve point for a specific position

Parameters

pos	Position, where to look for the closest curve point
dist	If dist != NULL, closestPoint() returns the distance between the position and the closest curve point in paint device coordinates

Returns: Index of the closest curve point, or -1 if none can be found ( f.e when the curve has no points )

Note: closestPoint() implements a dumb algorithm, that iterates over all points

Definition at line 1054 of file qwt_plot_curve.cpp.

◆ curveFitter()

QwtCurveFitter * QwtPlotCurve::curveFitter ( ) const

Get the curve fitter. If curve fitting is disabled NULL is returned.

Returns: Curve fitter

See also: setCurveFitter(), Fitted

Definition at line 875 of file qwt_plot_curve.cpp.

◆ drawCurve()

void QwtPlotCurve::drawCurve	(	QPainter *	painter,
		int	style,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

protectedvirtual

Draw the line part (without symbols) of a curve interval.

Parameters

painter	Painter
style	curve style, see QwtPlotCurve::CurveStyle
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	index of the first point to be painted
to	index of the last point to be painted

See also: draw(), drawDots(), drawLines(), drawSteps(), drawSticks()

Definition at line 432 of file qwt_plot_curve.cpp.

◆ drawDots()

void QwtPlotCurve::drawDots	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

protectedvirtual

Draw dots

Parameters

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	index of the first point to be painted
to	index of the last point to be painted

See also: draw(), drawCurve(), drawSticks(), drawLines(), drawSteps()

Definition at line 643 of file qwt_plot_curve.cpp.

◆ drawLines()

void QwtPlotCurve::drawLines	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

protectedvirtual

Draw lines.

If the CurveAttribute Fitted is enabled a QwtCurveFitter tries to interpolate/smooth the curve, before it is painted.

Parameters

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	index of the first point to be painted
to	index of the last point to be painted

See also: setCurveAttribute(), setCurveFitter(), draw(), drawLines(), drawDots(), drawSteps(), drawSticks()

Definition at line 479 of file qwt_plot_curve.cpp.

◆ drawSeries()

void QwtPlotCurve::drawSeries	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

overridevirtual

Draw an interval of the curve

Parameters

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
canvasRect	Contents rectangle of the canvas
from	Index of the first point to be painted
to	Index of the last point to be painted. If to < 0 the curve will be painted to its last point.

See also: drawCurve(), drawSymbols(),

Implements QwtPlotSeriesItem.

Definition at line 384 of file qwt_plot_curve.cpp.

◆ drawSteps()

void QwtPlotCurve::drawSteps	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

protectedvirtual

Draw step function

The direction of the steps depends on Inverted attribute.

Parameters

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	index of the first point to be painted
to	index of the last point to be painted

See also: CurveAttribute, setCurveAttribute(), draw(), drawCurve(), drawDots(), drawLines(), drawSticks()

Definition at line 744 of file qwt_plot_curve.cpp.

◆ drawSticks()

void QwtPlotCurve::drawSticks	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

protectedvirtual

Draw sticks

Parameters

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	index of the first point to be painted
to	index of the last point to be painted

See also: draw(), drawCurve(), drawDots(), drawLines(), drawSteps()

Definition at line 588 of file qwt_plot_curve.cpp.

◆ drawSymbols()

void QwtPlotCurve::drawSymbols	(	QPainter *	painter,
		const QwtSymbol &	symbol,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to ) const

protectedvirtual

Draw symbols

Parameters

painter	Painter
symbol	Curve symbol
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	Index of the first point to be painted
to	Index of the last point to be painted

See also: setSymbol(), drawSeries(), drawCurve()

Definition at line 982 of file qwt_plot_curve.cpp.

◆ fillCurve()

void QwtPlotCurve::fillCurve	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		QPolygonF &	polygon ) const

protectedvirtual

Fill the area between the curve and the baseline with the curve brush

Parameters

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
polygon	Polygon - will be modified !

See also: setBrush(), setBaseline(), setStyle()

Definition at line 892 of file qwt_plot_curve.cpp.

◆ init()

void QwtPlotCurve::init ( )

protected

Initialize internal members.

Definition at line 136 of file qwt_plot_curve.cpp.

◆ interpolatedValueAt()

qreal QwtPlotCurve::interpolatedValueAt	(	Qt::Orientation	orientation,
		double	value ) const

Calculate a fictive curve point by interpolating between the adjacent points. The curve points have to be monotonic in direction of the orientation.

Parameters

orientation	For Qt::Horizontal value is a x coordinate and a y coordinate is returned. For Qt::Vertical value is a x coordinate
value	x or y coordinate, depending on the orientation

Returns: Interpolated coordinate or qQNaN() if value is outside the bounding rectangle of the curve

Note: The implementation uses a binary search algorithm and requires the points being ordered in direction of the orientation.

See also: adjacentPoint()

Definition at line 1158 of file qwt_plot_curve.cpp.

◆ legendAttributes()

QwtPlotCurve::LegendAttributes QwtPlotCurve::legendAttributes ( ) const

Returns: Attributes how to draw the legend icon

See also: setLegendAttributes(), testLegendAttribute()

Definition at line 228 of file qwt_plot_curve.cpp.

◆ legendIcon()

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

overridevirtual

Returns: Icon representing the curve on the legend

Parameters

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

See also: QwtPlotItem::setLegendIconSize(), QwtPlotItem::legendData()

Reimplemented from QwtPlotItem.

Definition at line 1223 of file qwt_plot_curve.cpp.

◆ maxXValue()

double QwtPlotCurve::maxXValue ( ) const

inline

boundingRect().right()

Definition at line 358 of file qwt_plot_curve.h.

◆ maxYValue()

double QwtPlotCurve::maxYValue ( ) const

inline

boundingRect().bottom()

Definition at line 370 of file qwt_plot_curve.h.

◆ minXValue()

double QwtPlotCurve::minXValue ( ) const

inline

boundingRect().left()

Definition at line 352 of file qwt_plot_curve.h.

◆ minYValue()

double QwtPlotCurve::minYValue ( ) const

inline

boundingRect().top()

Definition at line 364 of file qwt_plot_curve.h.

◆ pen()

const QPen & QwtPlotCurve::pen ( ) const

Returns: Pen used to draw the lines

See also: setPen(), brush()

Definition at line 331 of file qwt_plot_curve.cpp.

◆ rtti()

int QwtPlotCurve::rtti ( ) const

overridevirtual

Returns: QwtPlotItem::Rtti_PlotCurve

Reimplemented from QwtPlotItem.

Definition at line 148 of file qwt_plot_curve.cpp.

◆ setBaseline()

void QwtPlotCurve::setBaseline ( double value )

Set the value of the baseline.

The baseline is needed for filling the curve with a brush or the Sticks drawing style.

The interpretation of the baseline depends on the orientation(). With Qt::Vertical, the baseline is interpreted as a horizontal line at y = baseline(), with Qt::Horizontal, it is interpreted as a vertical line at x = baseline().

The default value is 0.0.

Parameters

value Value of the baseline

See also: baseline(), setBrush(), setStyle(), QwtPlotAbstractSeriesItem::orientation()

Definition at line 1025 of file qwt_plot_curve.cpp.

◆ setBrush()

void QwtPlotCurve::setBrush ( const QBrush & brush )

Assign a brush.

In case of brush.style() != QBrush::NoBrush and style() != QwtPlotCurve::Sticks the area between the curve and the baseline will be filled.

In case !brush.color().isValid() the area will be filled by pen.color(). The fill algorithm simply connects the first and the last curve point to the baseline. So the curve data has to be sorted (ascending or descending).

Parameters

brush New brush

See also: brush(), setBaseline(), baseline()

Definition at line 351 of file qwt_plot_curve.cpp.

◆ setCurveAttribute()

void QwtPlotCurve::setCurveAttribute	(	CurveAttribute	attribute,
		bool	on = true )

Specify an attribute for drawing the curve

Parameters

attribute	Curve attribute
on	On/Off

/sa testCurveAttribute(), setCurveFitter()

Definition at line 822 of file qwt_plot_curve.cpp.

◆ setCurveFitter()

void QwtPlotCurve::setCurveFitter ( QwtCurveFitter * curveFitter )

Assign a curve fitter

The curve fitter "smooths" the curve points, when the Fitted CurveAttribute is set. setCurveFitter(NULL) also disables curve fitting.

The curve fitter operates on the translated points ( = widget coordinates) to be functional for logarithmic scales. Obviously this is less performant for fitting algorithms, that reduce the number of points.

For situations, where curve fitting is used to improve the performance of painting huge series of points it might be better to execute the fitter on the curve points once and to cache the result in the QwtSeriesData object.

Parameters

curveFitter() Curve fitter

See also: Fitted

Definition at line 861 of file qwt_plot_curve.cpp.

◆ setLegendAttribute()

void QwtPlotCurve::setLegendAttribute	(	LegendAttribute	attribute,
		bool	on = true )

Specify an attribute how to draw the legend icon

Parameters

attribute	Attribute
on	On/Off /sa testLegendAttribute(). legendIcon()

Definition at line 184 of file qwt_plot_curve.cpp.

◆ setLegendAttributes()

void QwtPlotCurve::setLegendAttributes ( LegendAttributes attributes )

Specify the attributes how to draw the legend icon

Parameters

attributes Attributes /sa setLegendAttribute(). legendIcon()

Definition at line 213 of file qwt_plot_curve.cpp.

◆ setPaintAttribute()

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

Specify an attribute how to draw the curve

Parameters

attribute	Paint attribute
on	On/Off

See also: testPaintAttribute()

Definition at line 160 of file qwt_plot_curve.cpp.

◆ setPen() [1/2]

void QwtPlotCurve::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()

Definition at line 305 of file qwt_plot_curve.cpp.

◆ setPen() [2/2]

void QwtPlotCurve::setPen ( const QPen & pen )

Assign a pen

Parameters

pen New pen

See also: pen(), brush()

Definition at line 316 of file qwt_plot_curve.cpp.

◆ setRawSamples() [1/4]

void QwtPlotCurve::setRawSamples	(	const double *	xData,
		const double *	yData,
		int	size )

Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve.

setRawSamples is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerData class.

Parameters

xData	pointer to x data
yData	pointer to y data
size	size of x and y

See also: QwtCPointerData

Definition at line 1331 of file qwt_plot_curve.cpp.

◆ setRawSamples() [2/4]

void QwtPlotCurve::setRawSamples	(	const double *	yData,
		int	size )

Initialize the data by pointing to a memory block which is not managed by QwtPlotCurve.

The memory contains the y coordinates, while the index is interpreted as x coordinate.

setRawSamples() is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerValueData class.

Parameters

yData	pointer to y data
size	size of x and y

See also: QwtCPointerData

Definition at line 1373 of file qwt_plot_curve.cpp.

◆ setRawSamples() [3/4]

void QwtPlotCurve::setRawSamples	(	const float *	xData,
		const float *	yData,
		int	size )

Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve.

setRawSamples is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerData class.

Parameters

xData	pointer to x data
yData	pointer to y data
size	size of x and y

See also: QwtCPointerData

Definition at line 1351 of file qwt_plot_curve.cpp.

◆ setRawSamples() [4/4]

void QwtPlotCurve::setRawSamples	(	const float *	yData,
		int	size )

Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve.

The memory contains the y coordinates, while the index is interpreted as x coordinate.

setRawSamples() is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerValueData class.

Parameters

yData	pointer to y data
size	size of x and y

See also: QwtCPointerData

Definition at line 1394 of file qwt_plot_curve.cpp.

◆ setSamples() [1/10]

void QwtPlotCurve::setSamples	(	const double *	xData,
		const double *	yData,
		int	size )

Set data by copying x- and y-values from specified memory blocks. Contrary to setRawSamples(), this function makes a 'deep copy' of the data.

Parameters

xData	pointer to x values
yData	pointer to y values
size	size of xData and yData

See also: QwtPointArrayData

Definition at line 1410 of file qwt_plot_curve.cpp.

◆ setSamples() [2/10]

void QwtPlotCurve::setSamples	(	const double *	yData,
		int	size )

Set data by copying y-values from a specified memory block.

The memory contains the y coordinates, while the index is interpreted as x coordinate.

Parameters

yData	y data
size	size of yData

See also: QwtValuePointData

Definition at line 1472 of file qwt_plot_curve.cpp.

◆ setSamples() [3/10]

void QwtPlotCurve::setSamples	(	const float *	xData,
		const float *	yData,
		int	size )

Set data by copying x- and y-values from specified memory blocks. Contrary to setRawSamples(), this function makes a 'deep copy' of the data.

Parameters

xData	pointer to x values
yData	pointer to y values
size	size of xData and yData

See also: QwtPointArrayData

Definition at line 1427 of file qwt_plot_curve.cpp.

◆ setSamples() [4/10]

void QwtPlotCurve::setSamples	(	const float *	yData,
		int	size )

Set data by copying y-values from a specified memory block.

The vector contains the y coordinates, while the index is interpreted as x coordinate.

Parameters

yData	y data
size	size of yData

See also: QwtValuePointData

Definition at line 1488 of file qwt_plot_curve.cpp.

◆ setSamples() [5/10]

void QwtPlotCurve::setSamples	(	const QVector< double > &	xData,
		const QVector< double > &	yData )

Initialize data with x- and y-arrays (explicitly shared)

Parameters

xData	x data
yData	y data

See also: QwtPointArrayData

Definition at line 1441 of file qwt_plot_curve.cpp.

◆ setSamples() [6/10]

void QwtPlotCurve::setSamples ( const QVector< double > & yData )

Initialize data with an array of y values (explicitly shared)

The vector contains the y coordinates, while the index is the x coordinate.

Parameters

yData y data

See also: QwtValuePointData

Definition at line 1503 of file qwt_plot_curve.cpp.

◆ setSamples() [7/10]

void QwtPlotCurve::setSamples	(	const QVector< float > &	xData,
		const QVector< float > &	yData )

Initialize data with x- and y-arrays (explicitly shared)

Parameters

xData	x data
yData	y data

See also: QwtPointArrayData

Definition at line 1455 of file qwt_plot_curve.cpp.

◆ setSamples() [8/10]

void QwtPlotCurve::setSamples ( const QVector< float > & yData )

Initialize data with an array of y values (explicitly shared)

The vector contains the y coordinates, while the index is the x coordinate.

Parameters

yData y data

See also: QwtValuePointData

Definition at line 1518 of file qwt_plot_curve.cpp.

◆ setSamples() [9/10]

void QwtPlotCurve::setSamples ( const QVector< QPointF > & samples )

Initialize data with an array of points.

Parameters

samples Vector of points

Note: QVector is implicitly shared; QPolygonF is derived from QVector<QPointF>

Definition at line 1312 of file qwt_plot_curve.cpp.

◆ setSamples() [10/10]

void QwtPlotCurve::setSamples ( QwtSeriesData< QPointF > * data )

Assign a series of points

setSamples() is just a wrapper for setData() without any additional value - beside that it is easier to find for the developer.

Parameters

data Data

Warning: The item takes ownership of the data object, deleting it when its not used anymore.

Definition at line 1300 of file qwt_plot_curve.cpp.

◆ setStyle()

void QwtPlotCurve::setStyle ( CurveStyle style )

Set the curve's drawing style

Parameters

style Curve style

See also: style()

Definition at line 239 of file qwt_plot_curve.cpp.

◆ setSymbol()

void QwtPlotCurve::setSymbol ( QwtSymbol * symbol )

Assign a symbol.

The curve will take the ownership of the symbol, hence the previously set symbol will be delete by setting a new one. If symbol is NULL no symbol will be drawn.

Parameters

symbol Symbol

See also: symbol()

Definition at line 269 of file qwt_plot_curve.cpp.

◆ style()

QwtPlotCurve::CurveStyle QwtPlotCurve::style ( ) const

Returns: Style of the curve

See also: setStyle()

Definition at line 254 of file qwt_plot_curve.cpp.

◆ symbol()

const QwtSymbol * QwtPlotCurve::symbol ( ) const

Returns: Current symbol or NULL, when no symbol has been assigned

See also: setSymbol()

Definition at line 287 of file qwt_plot_curve.cpp.

◆ testCurveAttribute()

bool QwtPlotCurve::testCurveAttribute ( CurveAttribute attribute ) const

Returns: true, if attribute is enabled

See also: setCurveAttribute()

Definition at line 839 of file qwt_plot_curve.cpp.

◆ testLegendAttribute()

bool QwtPlotCurve::testLegendAttribute ( LegendAttribute attribute ) const

Returns: True, when attribute is enabled

See also: setLegendAttribute()

Definition at line 202 of file qwt_plot_curve.cpp.

◆ testPaintAttribute()

bool QwtPlotCurve::testPaintAttribute ( PaintAttribute attribute ) const

Returns: True, when attribute is enabled

See also: setPaintAttribute()

Definition at line 172 of file qwt_plot_curve.cpp.

Public Types

Public Member Functions

Protected Member Functions

Detailed Description

Member Typedef Documentation

◆ CurveAttributes

◆ LegendAttributes

◆ PaintAttributes

Member Enumeration Documentation

◆ CurveAttribute

◆ CurveStyle

◆ LegendAttribute

◆ PaintAttribute

Constructor & Destructor Documentation

◆ QwtPlotCurve() [1/2]

◆ QwtPlotCurve() [2/2]

◆ ~QwtPlotCurve()

Member Function Documentation

◆ adjacentPoint()

◆ baseline()

◆ brush()

◆ closePolyline()

◆ closestPoint()

◆ curveFitter()

◆ drawCurve()

◆ drawDots()

◆ drawLines()

◆ drawSeries()

◆ drawSteps()

◆ drawSticks()

◆ drawSymbols()

◆ fillCurve()

◆ init()

◆ interpolatedValueAt()

◆ legendAttributes()

◆ legendIcon()

◆ maxXValue()

◆ maxYValue()

◆ minXValue()

◆ minYValue()

◆ pen()

◆ rtti()

◆ setBaseline()

◆ setBrush()

◆ setCurveAttribute()

◆ setCurveFitter()

◆ setLegendAttribute()

◆ setLegendAttributes()

◆ setPaintAttribute()

◆ setPen() [1/2]

◆ setPen() [2/2]

◆ setRawSamples() [1/4]

◆ setRawSamples() [2/4]

◆ setRawSamples() [3/4]

◆ setRawSamples() [4/4]

◆ setSamples() [1/10]

◆ setSamples() [2/10]

◆ setSamples() [3/10]

◆ setSamples() [4/10]

◆ setSamples() [5/10]

◆ setSamples() [6/10]

◆ setSamples() [7/10]

◆ setSamples() [8/10]

◆ setSamples() [9/10]

◆ setSamples() [10/10]

◆ setStyle()

◆ setSymbol()

◆ style()

◆ symbol()

◆ testCurveAttribute()

◆ testLegendAttribute()

◆ testPaintAttribute()