QwtPlotMarker.qt5 - Man Page


#include <qwt_plot_marker.h>

Inherits QwtPlotItem.

Public Types

enum LineStyle { NoLine, HLine, VLine, Cross }

Public Member Functions

QwtPlotMarker ()
virtual ~QwtPlotMarker ()
virtual QwtDoubleRect boundingRect () const
virtual void draw (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &) const
QwtText label () const
Qt::Alignment labelAlignment () const
Qt::Orientation labelOrientation () const
const QPen & linePen () const
LineStyle lineStyle () const
virtual int rtti () const
void setLabel (const QwtText &)
void setLabelAlignment (Qt::Alignment)
void setLabelOrientation (Qt::Orientation)
void setLinePen (const QPen &p)
void setLineStyle (LineStyle st)
void setSpacing (int)
void setSymbol (const QwtSymbol &s)
void setValue (double, double)
void setValue (const QwtDoublePoint &)
void setXValue (double)
void setYValue (double)
int spacing () const
const QwtSymbol & symbol () const
QwtDoublePoint value () const
double xValue () const
double yValue () const

Protected Member Functions

void drawAt (QPainter *, const QRect &, const QPoint &) const

Detailed Description

A class for drawing markers.

A marker can be a horizontal line, a vertical line, a symbol, a label or any combination of them, which can be drawn around a center point inside a bounding rectangle.

The QwtPlotMarker::setSymbol() member assigns a symbol to the marker. The symbol is drawn at the specified point.

With QwtPlotMarker::setLabel(), a label can be assigned to the marker. The QwtPlotMarker::setLabelAlignment() member specifies where the label is drawn. All the Align*-constants in Qt::AlignmentFlags (see Qt documentation) are valid. The interpretation of the alignment depends on the marker's line style. The alignment refers to the center point of the marker, which means, for example, that the label would be printed left above the center point if the alignment was set to AlignLeft|AlignTop.

Member Enumeration Documentation

enum QwtPlotMarker::LineStyle

Line styles.

See also:

setLineStyle(), lineStyle()

Member Function Documentation

QwtDoubleRect QwtPlotMarker::boundingRect () const [virtual]


An invalid bounding rect: QwtDoubleRect(1.0, 1.0, -2.0, -2.0)

Reimplemented from QwtPlotItem.

void QwtPlotMarker::draw (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &canvasRect) const [virtual]

Draw the marker


painter Painter
xMap x Scale Map
yMap y Scale Map
canvasRect Contents rect of the canvas in painter coordinates

Implements QwtPlotItem.

void QwtPlotMarker::drawAt (QPainter *painter, const QRect &canvasRect, const QPoint &pos) const [protected]

Draw the marker at a specific position


painter Painter
canvasRect Contents rect of the canvas in painter coordinates
pos Position of the marker in painter coordinates

QwtText QwtPlotMarker::label () const


the label

See also:


Qt::Alignment QwtPlotMarker::labelAlignment () const


the label alignment

See also:

setLabelAlignment(), setLabelOrientation()

Qt::Orientation QwtPlotMarker::labelOrientation () const


the label orientation

See also:

setLabelOrientation(), labelAlignment()

const QPen & QwtPlotMarker::linePen () const


the line pen

See also:


QwtPlotMarker::LineStyle QwtPlotMarker::lineStyle () const


the line style

See also:

For a description of line styles, see QwtPlotMarker::setLineStyle()

int QwtPlotMarker::rtti () const [virtual]



Reimplemented from QwtPlotItem.

void QwtPlotMarker::setLabel (const QwtText &label)

Set the label. Parameters:

label label text

See also:


void QwtPlotMarker::setLabelAlignment (Qt::Alignmentalign)

Set the alignment of the label. In case of QwtPlotMarker::HLine the alignment is relative to the y position of the marker, but the horizontal flags correspond to the canvas rectangle. In case of QwtPlotMarker::VLine the alignment is relative to the x position of the marker, but the vertical flags correspond to the canvas rectangle.

In all other styles the alignment is relative to the marker's position.


align Alignment. A combination of AlignTop, AlignBottom, AlignLeft, AlignRight, AlignCenter, AlgnHCenter, AlignVCenter.

See also:

labelAlignment(), labelOrientation()

void QwtPlotMarker::setLabelOrientation (Qt::Orientationorientation)

Set the orientation of the label. When orientation is Qt::Vertical the label is rotated by 90.0 degrees ( from bottom to top ).


orientation Orientation of the label

See also:

labelOrientation(), setLabelAlignment()

void QwtPlotMarker::setLinePen (const QPen &pen)

Specify a pen for the line.

The width of non cosmetic pens is scaled according to the resolution of the paint device.


pen New pen

See also:

linePen(), QwtPainter::scaledPen()

void QwtPlotMarker::setLineStyle (QwtPlotMarker::LineStylest)

Set the line style. Parameters:

st Line style. Can be one of QwtPlotMarker::NoLine, HLine, VLine or Cross

See also:


void QwtPlotMarker::setSpacing (intspacing)

Set the spacing. When the label is not centered on the marker position, the spacing is the distance between the position and the label.


spacing Spacing

See also:

spacing(), setLabelAlignment()

void QwtPlotMarker::setSymbol (const QwtSymbol &s)

Assign a symbol. Parameters:

s New symbol

See also:


int QwtPlotMarker::spacing () const


the spacing

See also:


const QwtSymbol & QwtPlotMarker::symbol () const


the symbol

See also:

setSymbol(), QwtSymbol


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


Tue Nov 20 2012 Version 5.2.3 Qwt User's Guide