source: ntrip/trunk/BNC/qwtpolar/qwt_polar_picker.cpp@ 8720

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * QwtPolar Widget Library
 * Copyright (C) 2008   Uwe Rathmann
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *****************************************************************************/

#include "qwt_polar_picker.h"
#include "qwt_polar_plot.h"
#include "qwt_polar_canvas.h"
#include <qwt_scale_map.h>
#include <qwt_picker_machine.h>
#include <qwt_point_polar.h>

class QwtPolarPicker::PrivateData
{
public:
    PrivateData()
    {
    }
};

/*!
  \brief Create a polar plot picker
  \param canvas Plot canvas to observe, also the parent object
*/

QwtPolarPicker::QwtPolarPicker( QwtPolarCanvas *canvas ):
    QwtPicker( canvas )
{
    d_data = new PrivateData;
}

/*!
  Create a plot picker

  \param rubberBand Rubberband style
  \param trackerMode Tracker mode
  \param canvas Plot canvas to observe, also the parent object

  \sa QwtPicker, QwtPicker::setSelectionFlags(), QwtPicker::setRubberBand(),
      QwtPicker::setTrackerMode

  \sa QwtPolarPlot::autoReplot(), QwtPolarPlot::replot(), scaleRect()
*/
QwtPolarPicker::QwtPolarPicker( 
        RubberBand rubberBand, DisplayMode trackerMode,
        QwtPolarCanvas *canvas ):
    QwtPicker( rubberBand, trackerMode, canvas )
{
    d_data = new PrivateData;
}

//! Destructor
QwtPolarPicker::~QwtPolarPicker()
{
    delete d_data;
}

//! \return Observed plot canvas
QwtPolarCanvas *QwtPolarPicker::canvas()
{
    return qobject_cast<QwtPolarCanvas *>( parentWidget() );
}

//! \return Observed plot canvas
const QwtPolarCanvas *QwtPolarPicker::canvas() const
{
    return qobject_cast<const QwtPolarCanvas *>( parentWidget() );
}

//! \return Plot widget, containing the observed plot canvas
QwtPolarPlot *QwtPolarPicker::plot()
{
    QwtPolarCanvas *w = canvas();
    if ( w )
        return w->plot();

    return NULL;
}

//! \return Plot widget, containing the observed plot canvas
const QwtPolarPlot *QwtPolarPicker::plot() const
{
    const QwtPolarCanvas *w = canvas();
    if ( w )
        return w->plot();

    return NULL;
}

/*!
  Translate a pixel position into a position string

  \param pos Position in pixel coordinates
  \return Position string
*/
QwtText QwtPolarPicker::trackerText( const QPoint &pos ) const
{
    const QwtPointPolar polarPoint = invTransform( pos );
    return trackerTextPolar( polarPoint );
}

/*!
  \brief 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".

  \param pos Position
  \return Position string
*/
QwtText QwtPolarPicker::trackerTextPolar( const QwtPointPolar &pos ) const
{
    QString text;
    text.sprintf( "%.4f, %.4f", pos.radius(), pos.azimuth() );

    return QwtText( text );
}

/*!
  Append a point to the selection and update rubberband and tracker.

  \param pos Additional point
  \sa isActive, begin(), end(), move(), appended()

  \note The appended(const QPoint &), appended(const QDoublePoint &)
        signals are emitted.
*/
void QwtPolarPicker::append( const QPoint &pos )
{
    QwtPicker::append( pos );
    Q_EMIT appended( invTransform( pos ) );
}

/*!
  Move the last point of the selection

  \param pos New position
  \sa isActive, begin(), end(), append()

  \note The moved(const QPoint &), moved(const QDoublePoint &)
        signals are emitted.
*/
void QwtPolarPicker::move( const QPoint &pos )
{
    QwtPicker::move( pos );
    Q_EMIT moved( invTransform( pos ) );
}

/*!
  Close a selection setting the state to inactive.

  \param ok If true, complete the selection and emit selected signals
            otherwise discard the selection.
  \return true if the selection is accepted, false otherwise
*/

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

    QwtPolarPlot *plot = QwtPolarPicker::plot();
    if ( !plot )
        return false;

    const QPolygon points = selection();
    if ( points.count() == 0 )
        return false;

    QwtPickerMachine::SelectionType selectionType =
        QwtPickerMachine::NoSelection;

    if ( stateMachine() )
        selectionType = stateMachine()->selectionType();

    switch ( selectionType )
    {
        case QwtPickerMachine::PointSelection:
        {
            const QwtPointPolar pos = invTransform( points[0] );
            Q_EMIT selected( pos );
            break;
        }
        case QwtPickerMachine::RectSelection:
        case QwtPickerMachine::PolygonSelection:
        {
            QVector<QwtPointPolar> polarPoints( points.count() );
            for ( int i = 0; i < points.count(); i++ )
                polarPoints[i] = invTransform( points[i] );

            Q_EMIT selected( polarPoints );
        }
        default:
            break;
    }

    return true;
}

/*!
    Translate a point from widget into plot coordinates

    \param pos Point in widget coordinates of the plot canvas
    \return Point in plot coordinates
    \sa transform(), canvas()
*/
QwtPointPolar QwtPolarPicker::invTransform( const QPoint &pos ) const
{
    QwtPointPolar polarPos;
    if ( canvas() == NULL )
        return QwtPointPolar();

    return canvas()->invTransform( pos );
}

/*!
    \return Bounding rectangle of the region, where picking is
            supported.
*/
QRect QwtPolarPicker::pickRect() const
{
    const QRect cr = canvas()->contentsRect();
    const QRect pr = plot()->plotRect( cr ).toRect();

    return cr & pr;
}

QPainterPath QwtPolarPicker::pickArea() const
{
    const QRect cr = canvas()->contentsRect();

    QPainterPath crPath;
    crPath.addRect( cr );

    QPainterPath prPath;
    prPath.addEllipse( plot()->plotRect( cr ) );

    return crPath.intersected( prPath );
}