qwt_plot_picker.cpp

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/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   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_plot_picker.h"
#include "qwt_plot.h"
#include "qwt_scale_div.h"
#include "qwt_painter.h"
#include "qwt_scale_map.h"
#include "qwt_picker_machine.h"

QwtPlotPicker::QwtPlotPicker( QWidget *canvas ):
    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( int xAxis, int yAxis, QWidget *canvas ):
    QwtPicker( canvas ),
    d_xAxis( xAxis ),
    d_yAxis( yAxis )
{
}

QwtPlotPicker::QwtPlotPicker( int xAxis, int yAxis,
        RubberBand rubberBand, DisplayMode trackerMode,
        QWidget *canvas ):
    QwtPicker( rubberBand, trackerMode, canvas ),
    d_xAxis( xAxis ),
    d_yAxis( yAxis )
{
}

QwtPlotPicker::~QwtPlotPicker()
{
}

QWidget *QwtPlotPicker::canvas()
{
    return parentWidget();
}

const QWidget *QwtPlotPicker::canvas() const
{
    return parentWidget();
}

QwtPlot *QwtPlotPicker::plot()
{
    QWidget *w = canvas();
    if ( w )
        w = w->parentWidget();

    return qobject_cast<QwtPlot *>( w );
}

const QwtPlot *QwtPlotPicker::plot() const
{
    const QWidget *w = canvas();
    if ( w )
        w = w->parentWidget();

    return qobject_cast<const QwtPlot *>( w );
}

QRectF QwtPlotPicker::scaleRect() const
{
    QRectF rect;

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

        rect = QRectF( xs.lowerBound(), ys.lowerBound(),
            xs.range(), ys.range() );
        rect = rect.normalized();
    }

    return rect;
}

void QwtPlotPicker::setAxis( int xAxis, int yAxis )
{
    const QwtPlot *plt = plot();
    if ( !plt )
        return;

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

int QwtPlotPicker::xAxis() const
{
    return d_xAxis;
}

int QwtPlotPicker::yAxis() const
{
    return d_yAxis;
}

QwtText QwtPlotPicker::trackerText( const QPoint &pos ) const
{
    if ( plot() == NULL )
        return QwtText();

    return trackerTextF( invTransform( pos ) );
}

QwtText QwtPlotPicker::trackerTextF( const QPointF &pos ) const
{
    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 );
}

void QwtPlotPicker::append( const QPoint &pos )
{
    QwtPicker::append( pos );
    Q_EMIT appended( invTransform( pos ) );
}

void QwtPlotPicker::move( const QPoint &pos )
{
    QwtPicker::move( pos );
    Q_EMIT moved( invTransform( pos ) );
}

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

    QwtPlot *plot = QwtPlotPicker::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 QPointF pos = invTransform( points.first() );
            Q_EMIT selected( pos );
            break;
        }
        case QwtPickerMachine::RectSelection:
        {
            if ( points.count() >= 2 )
            {
                const QPoint p1 = points.first();
                const QPoint p2 = points.last();

                const QRect rect = QRect( p1, p2 ).normalized();
                Q_EMIT selected( invTransform( rect ) );
            }
            break;
        }
        case QwtPickerMachine::PolygonSelection:
        {
            QVector<QPointF> dpa( points.count() );
            for ( int i = 0; i < points.count(); i++ )
                dpa[i] = invTransform( points[i] );

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

    return true;
}

QRectF QwtPlotPicker::invTransform( const QRect &rect ) const
{
    const QwtScaleMap xMap = plot()->canvasMap( d_xAxis );
    const QwtScaleMap yMap = plot()->canvasMap( d_yAxis );

    return QwtScaleMap::invTransform( xMap, yMap, rect );
}

QRect QwtPlotPicker::transform( const QRectF &rect ) const
{
    const QwtScaleMap xMap = plot()->canvasMap( d_xAxis );
    const QwtScaleMap yMap = plot()->canvasMap( d_yAxis );

    return QwtScaleMap::transform( xMap, yMap, rect ).toRect();
}

QPointF QwtPlotPicker::invTransform( const QPoint &pos ) const
{
    QwtScaleMap xMap = plot()->canvasMap( d_xAxis );
    QwtScaleMap yMap = plot()->canvasMap( d_yAxis );

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

QPoint QwtPlotPicker::transform( const QPointF &pos ) const
{
    QwtScaleMap xMap = plot()->canvasMap( d_xAxis );
    QwtScaleMap yMap = plot()->canvasMap( d_yAxis );

    const QPointF p( xMap.transform( pos.x() ),
        yMap.transform( pos.y() ) );

    return p.toPoint();
}