QwtPlotPicker provides selections on a plot canvas. More...

#include <qwt_plot_picker.h>

Inheritance diagram for QwtPlotPicker:

Collaboration diagram for QwtPlotPicker:

Signals
void	selected (const QwtDoublePoint &pos)
void	selected (const QwtDoubleRect &rect)
void	selected (const QMemArray< QwtDoublePoint > &pa)
void	appended (const QwtDoublePoint &pos)
void	moved (const QwtDoublePoint &pos)
Public Member Functions
	QwtPlotPicker (QwtPlotCanvas *)
	Create a plot picker.
virtual	~QwtPlotPicker ()
	Destructor.
	QwtPlotPicker (int xAxis, int yAxis, QwtPlotCanvas *)
	QwtPlotPicker (int xAxis, int yAxis, int selectionFlags, RubberBand rubberBand, DisplayMode trackerMode, QwtPlotCanvas *)
virtual void	setAxis (int xAxis, int yAxis)
int	xAxis () const
	Return x axis.
int	yAxis () const
	Return y axis.
QwtPlot *	plot ()
	Return plot widget, containing the observed plot canvas.
const QwtPlot *	plot () const
	Return plot widget, containing the observed plot canvas.
QwtPlotCanvas *	canvas ()
	Return observed plot canvas.
const QwtPlotCanvas *	canvas () const
	Return Observed plot canvas.
Protected Member Functions
QwtDoubleRect	scaleRect () const
QwtDoubleRect	invTransform (const QRect &) const
QRect	transform (const QwtDoubleRect &) const
QwtDoublePoint	invTransform (const QPoint &) const
QPoint	transform (const QwtDoublePoint &) const
virtual QwtText	trackerText (const QPoint &) const
virtual QwtText	trackerText (const QwtDoublePoint &) const
	Translate a position into a position string.
virtual void	move (const QPoint &)
virtual void	append (const QPoint &)
virtual bool	end (bool ok=true)

Detailed Description

QwtPlotPicker provides selections on a plot canvas.

QwtPlotPicker is a QwtPicker tailored for selections on a plot canvas. It is set to a x-Axis and y-Axis and translates all pixel coordinates into this coodinate system.

Definition at line 29 of file qwt_plot_picker.h.

Constructor & Destructor Documentation

QwtPlotPicker::QwtPlotPicker ( QwtPlotCanvas * canvas ) [explicit]

Create a plot picker.

The picker is set to those x- and y-axis of the plot that are enabled. If both or no x-axis are enabled, the picker is set to QwtPlot::xBottom. If both or no y-axis are enabled, it is set to QwtPlot::yLeft.

Parameters:

canvas Plot canvas to observe, also the parent object

See also:: QwtPlot::autoReplot(), QwtPlot::replot(), QwtPlotPicker::scaleRect()

Definition at line 32 of file qwt_plot_picker.cpp.

References QwtPlot::axisEnabled(), plot(), setAxis(), xAxis(), QwtPlot::xBottom, QwtPlot::xTop, yAxis(), QwtPlot::yLeft, and QwtPlot::yRight.

                                                 :
    QwtPicker(canvas),
    d_xAxis(-1),
    d_yAxis(-1)
{
    if ( !canvas )
        return;

    // attach axes

    int xAxis = QwtPlot::xBottom;

    const QwtPlot *plot = QwtPlotPicker::plot();
    if ( !plot->axisEnabled(QwtPlot::xBottom) &&
        plot->axisEnabled(QwtPlot::xTop) )
    {
        xAxis = QwtPlot::xTop;
    }

    int yAxis = QwtPlot::yLeft;
    if ( !plot->axisEnabled(QwtPlot::yLeft) &&
        plot->axisEnabled(QwtPlot::yRight) )
    {
        yAxis = QwtPlot::yRight;
    }

    setAxis(xAxis, yAxis);
}

QwtPlotPicker::~QwtPlotPicker ( ) [virtual]

Destructor.

Definition at line 103 of file qwt_plot_picker.cpp.

{
}

QwtPlotPicker::QwtPlotPicker	(	int	xAxis,
		int	yAxis,
		QwtPlotCanvas *	canvas
	)		`[explicit]`

Create a plot picker

Parameters:

xAxis	Set the x axis of the picker
yAxis	Set the y axis of the picker
canvas	Plot canvas to observe, also the parent object

See also:: QwtPlot::autoReplot(), QwtPlot::replot(), QwtPlotPicker::scaleRect()

Definition at line 70 of file qwt_plot_picker.cpp.

                                                                       :
    QwtPicker(canvas),
    d_xAxis(xAxis),
    d_yAxis(yAxis)
{
}

QwtPlotPicker::QwtPlotPicker	(	int	xAxis,
		int	yAxis,
		int	selectionFlags,
		RubberBand	rubberBand,
		DisplayMode	trackerMode,
		QwtPlotCanvas *	canvas
	)		`[explicit]`

Create a plot picker

Parameters:

xAxis	X axis of the picker
yAxis	Y axis of the picker
selectionFlags	Or'd value of SelectionType, RectSelectionType and SelectionMode
rubberBand	Rubberband style
trackerMode	Tracker mode
canvas	Plot canvas to observe, also the parent object

See also:: QwtPicker, QwtPicker::setSelectionFlags(), QwtPicker::setRubberBand(), QwtPicker::setTrackerMode; QwtPlot::autoReplot(), QwtPlot::replot(), QwtPlotPicker::scaleRect()

Definition at line 93 of file qwt_plot_picker.cpp.

                              :
    QwtPicker(selectionFlags, rubberBand, trackerMode, canvas),
    d_xAxis(xAxis),
    d_yAxis(yAxis)
{
}

Member Function Documentation

void QwtPlotPicker::append ( const QPoint & pos ) [protected, virtual]

Append a point to the selection and update rubberband and tracker.

Parameters:

pos	Additional point

See also:: isActive, begin(), end(), move(), appended()

Note:: The appended(const QPoint &), appended(const QDoublePoint &) signals are emitted.

Reimplemented from QwtPicker.

Definition at line 249 of file qwt_plot_picker.cpp.

References appended(), and invTransform().

{
    QwtPicker::append(pos);
    emit appended(invTransform(pos));
}

void QwtPlotPicker::appended ( const QwtDoublePoint & pos ) [signal]

A signal emitted when a point has been appended to the selection

Parameters:

pos	Position of the appended point.

See also:: append(). moved()

Referenced by append().

QwtPlotCanvas * QwtPlotPicker::canvas ( )

Return observed plot canvas.

Definition at line 108 of file qwt_plot_picker.cpp.

References QwtPicker::parentWidget().

Referenced by plot().

{
    QWidget *w = parentWidget();
    if ( w && w->inherits("QwtPlotCanvas") )
        return (QwtPlotCanvas *)w;

    return NULL;
}

const QwtPlotCanvas * QwtPlotPicker::canvas ( ) const

Return Observed plot canvas.

Definition at line 118 of file qwt_plot_picker.cpp.

{
    return ((QwtPlotPicker *)this)->canvas();
}

bool QwtPlotPicker::end ( bool ok = true ) [protected, virtual]

Close a selection setting the state to inactive.

Parameters:

ok	If true, complete the selection and emit selected signals otherwise discard the selection.

Returns:: true if the selection is accepted, false otherwise

Reimplemented from QwtPicker.

Reimplemented in QwtPlotZoomer.

Definition at line 278 of file qwt_plot_picker.cpp.

References QwtPicker::CenterToCorner, QwtPicker::CenterToRadius, int(), invTransform(), plot(), QwtPicker::PointSelection, qwtAbs, qwtMax, QwtPicker::RectSelection, selected(), QwtPicker::selection(), and QwtPicker::selectionFlags().

{
    ok = QwtPicker::end(ok);
    if ( !ok )
        return false;

    QwtPlot *plot = QwtPlotPicker::plot();
    if ( !plot )
        return false;

    const QwtPolygon &pa = selection();
    if ( pa.count() == 0 )
        return false;

    if ( selectionFlags() & PointSelection )
    {
        const QwtDoublePoint pos = invTransform(pa[0]);
        emit selected(pos);
    }
    else if ( (selectionFlags() & RectSelection) && pa.count() >= 2 )
    {
        QPoint p1 = pa[0];
        QPoint p2 = pa[int(pa.count() - 1)];

        if ( selectionFlags() & CenterToCorner )
        {
            p1.setX(p1.x() - (p2.x() - p1.x()));
            p1.setY(p1.y() - (p2.y() - p1.y()));
        }
        else if ( selectionFlags() & CenterToRadius )
        {
            const int radius = qwtMax(qwtAbs(p2.x() - p1.x()),
                qwtAbs(p2.y() - p1.y()));
            p2.setX(p1.x() + radius);
            p2.setY(p1.y() + radius);
            p1.setX(p1.x() - radius);
            p1.setY(p1.y() - radius);
        }

        emit selected(invTransform(QRect(p1, p2)).normalized());
    }
    else 
    {
        QwtArray<QwtDoublePoint> dpa(pa.count());
        for ( int i = 0; i < int(pa.count()); i++ )
            dpa[i] = invTransform(pa[i]);

        emit selected(dpa);
    }

    return true;
}

QwtDoublePoint QwtPlotPicker::invTransform ( const QPoint & pos ) const [protected]

Translate a point from pixel into plot coordinates

Returns:: Point in plot coordinates

See also:: QwtPlotPicker::transform()

Definition at line 374 of file qwt_plot_picker.cpp.

References QwtPlot::canvasMap(), QwtScaleMap::invTransform(), and plot().

{
    QwtScaleMap xMap = plot()->canvasMap(d_xAxis);
    QwtScaleMap yMap = plot()->canvasMap(d_yAxis);

    return QwtDoublePoint(
        xMap.invTransform(pos.x()),
        yMap.invTransform(pos.y())
    );
}

QwtDoubleRect QwtPlotPicker::invTransform ( const QRect & rect ) const [protected]

Translate a rectangle from pixel into plot coordinates

Returns:: Rectangle in plot coordinates

See also:: QwtPlotPicker::transform()

Definition at line 337 of file qwt_plot_picker.cpp.

References QwtPlot::canvasMap(), QwtScaleMap::invTransform(), and plot().

Referenced by append(), QwtPlotZoomer::end(), end(), move(), and trackerText().

{
    QwtScaleMap xMap = plot()->canvasMap(d_xAxis);
    QwtScaleMap yMap = plot()->canvasMap(d_yAxis);

    const double left = xMap.invTransform(rect.left());
    const double right = xMap.invTransform(rect.right());
    const double top = yMap.invTransform(rect.top());
    const double bottom = yMap.invTransform(rect.bottom());

    return QwtDoubleRect(left, top,
        right - left, bottom - top);
}

void QwtPlotPicker::move ( const QPoint & pos ) [protected, virtual]

Move the last point of the selection

Parameters:

pos	New position

See also:: isActive, begin(), end(), append()

Note:: The moved(const QPoint &), moved(const QDoublePoint &) signals are emitted.

Reimplemented from QwtPicker.

Definition at line 264 of file qwt_plot_picker.cpp.

References invTransform(), and moved().

{
    QwtPicker::move(pos);
    emit moved(invTransform(pos));
}

void QwtPlotPicker::moved ( const QwtDoublePoint & pos ) [signal]

A signal emitted whenever the last appended point of the selection has been moved.

Parameters:

pos	Position of the moved last point of the selection.

See also:: move(), appended()

Referenced by move().

const QwtPlot * QwtPlotPicker::plot ( ) const

Return plot widget, containing the observed plot canvas.

Definition at line 138 of file qwt_plot_picker.cpp.

{
    return ((QwtPlotPicker *)this)->plot();
}

QwtPlot * QwtPlotPicker::plot ( )

Return plot widget, containing the observed plot canvas.

Definition at line 124 of file qwt_plot_picker.cpp.

References canvas().

Referenced by QwtPlotZoomer::end(), end(), invTransform(), QwtPlotPicker(), QwtPlotZoomer::rescale(), scaleRect(), setAxis(), QwtPlotZoomer::setZoomBase(), and transform().

{
    QObject *w = canvas();
    if ( w )
    {
        w = w->parent();
        if ( w && w->inherits("QwtPlot") )
            return (QwtPlot *)w;
    }

    return NULL;
}

QwtDoubleRect QwtPlotPicker::scaleRect ( ) const [protected]

Return normalized bounding rect of the axes

See also:: QwtPlot::autoReplot(), QwtPlot::replot().

Definition at line 148 of file qwt_plot_picker.cpp.

References QwtPlot::axisScaleDiv(), QwtScaleDiv::lowerBound(), QwtDoubleRect::normalized(), plot(), QwtScaleDiv::range(), xAxis(), and yAxis().

Referenced by QwtPlotZoomer::rescale(), QwtPlotZoomer::setAxis(), and QwtPlotZoomer::setZoomBase().

{
    QwtDoubleRect rect;

    if ( plot() )
    {
        const QwtScaleDiv *xs = plot()->axisScaleDiv(xAxis());
        const QwtScaleDiv *ys = plot()->axisScaleDiv(yAxis());

        if ( xs && ys )
        {
            rect = QwtDoubleRect( xs->lowerBound(), ys->lowerBound(), 
                xs->range(), ys->range() );
            rect = rect.normalized();
        }
    }

    return rect;
}

void QwtPlotPicker::selected ( const QwtDoublePoint & pos ) [signal]

A signal emitted in case of selectionFlags() & PointSelection.

Parameters:

pos	Selected point

Referenced by end().

void QwtPlotPicker::selected ( const QwtDoubleRect & rect ) [signal]

A signal emitted in case of selectionFlags() & RectSelection.

Parameters:

rect	Selected rectangle

void QwtPlotPicker::selected ( const QMemArray< QwtDoublePoint > & pa ) [signal]

A signal emitting the selected points, at the end of a selection.

Parameters:

pa	Selected points

void QwtPlotPicker::setAxis	(	int	xAxis,
		int	yAxis
	)		`[virtual]`

Set the x and y axes of the picker

Parameters:

xAxis	X axis
yAxis	Y axis

Reimplemented in QwtPlotZoomer.

Definition at line 174 of file qwt_plot_picker.cpp.

References plot(), xAxis(), and yAxis().

Referenced by QwtPlotPicker().

{
    const QwtPlot *plt = plot();
    if ( !plt )
        return;

    if ( xAxis != d_xAxis || yAxis != d_yAxis )
    {
        d_xAxis = xAxis;
        d_yAxis = yAxis;
    }
}

QwtText QwtPlotPicker::trackerText ( const QwtDoublePoint & pos ) const [protected, virtual]

Translate a position into a position string.

In case of HLineRubberBand the label is the value of the y position, in case of VLineRubberBand the value of the x position. Otherwise the label contains x and y position separated by a ',' .

The format for the double to string conversion is "%.4f".

Parameters:

pos Position

Returns:: Position string

Definition at line 222 of file qwt_plot_picker.cpp.

References QwtPicker::HLineRubberBand, QwtPicker::rubberBand(), QwtPicker::VLineRubberBand, QwtDoublePoint::x(), and QwtDoublePoint::y().

{
    QString text;

    switch(rubberBand())
    {
        case HLineRubberBand:
            text.sprintf("%.4f", pos.y());
            break;
        case VLineRubberBand:
            text.sprintf("%.4f", pos.x());
            break;
        default:
            text.sprintf("%.4f, %.4f", pos.x(), pos.y());
    }
    return QwtText(text);
}

QwtText QwtPlotPicker::trackerText ( const QPoint & pos ) const [protected, virtual]

Translate a pixel position into a position string

Parameters:

pos	Position in pixel coordinates

Returns:: Position string

Reimplemented from QwtPicker.

Definition at line 205 of file qwt_plot_picker.cpp.

References invTransform().

{
    return trackerText(invTransform(pos));
}

QRect QwtPlotPicker::transform ( const QwtDoubleRect & rect ) const [protected]

Translate a rectangle from plot into pixel coordinates

Returns:: Rectangle in pixel coordinates

See also:: QwtPlotPicker::invTransform()

Definition at line 356 of file qwt_plot_picker.cpp.

References QwtDoubleRect::bottom(), QwtPlot::canvasMap(), QwtDoubleRect::left(), plot(), QwtDoubleRect::right(), QwtDoubleRect::top(), and QwtScaleMap::transform().

{
    QwtScaleMap xMap = plot()->canvasMap(d_xAxis);
    QwtScaleMap yMap = plot()->canvasMap(d_yAxis);

    const int left = xMap.transform(rect.left());
    const int right = xMap.transform(rect.right());
    const int top = yMap.transform(rect.top());
    const int bottom = yMap.transform(rect.bottom());

    return QRect(left, top, right - left, bottom - top);
}

QPoint QwtPlotPicker::transform ( const QwtDoublePoint & pos ) const [protected]

Translate a point from plot into pixel coordinates

Returns:: Point in pixel coordinates

See also:: QwtPlotPicker::invTransform()

Definition at line 390 of file qwt_plot_picker.cpp.

References QwtPlot::canvasMap(), plot(), QwtScaleMap::transform(), QwtDoublePoint::x(), and QwtDoublePoint::y().

{
    QwtScaleMap xMap = plot()->canvasMap(d_xAxis);
    QwtScaleMap yMap = plot()->canvasMap(d_yAxis);

    return QPoint(
        xMap.transform(pos.x()),
        yMap.transform(pos.y())
    );
}

int QwtPlotPicker::xAxis ( ) const

Return x axis.

Definition at line 188 of file qwt_plot_picker.cpp.

Referenced by QwtPlotPicker(), QwtPlotZoomer::rescale(), scaleRect(), QwtPlotZoomer::setAxis(), and setAxis().

{
    return d_xAxis;
}

int QwtPlotPicker::yAxis ( ) const

Return y axis.

Definition at line 194 of file qwt_plot_picker.cpp.

Referenced by QwtPlotPicker(), QwtPlotZoomer::rescale(), scaleRect(), QwtPlotZoomer::setAxis(), and setAxis().

{
    return d_yAxis;
}

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

QwtPlotPicker Class Reference

Signals

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation