qwt_polar_magnifier.cpp

/******************************************************************************
 * 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_magnifier.h"
#include "qwt_polar_plot.h"
#include "qwt_polar_canvas.h"
#include "qwt_scale_div.h"
#include "qwt_point_polar.h"
 
#include <qevent.h>
 
class QwtPolarMagnifier::PrivateData
{
  public:
    PrivateData()
        : unzoomKey( Qt::Key_Home )
        , unzoomKeyModifiers( Qt::NoModifier )
    {
    }
 
    int unzoomKey;
    int unzoomKeyModifiers;
};
 
QwtPolarMagnifier::QwtPolarMagnifier( QwtPolarCanvas* canvas )
    : QwtMagnifier( canvas )
{
    m_data = new PrivateData();
}
 
QwtPolarMagnifier::~QwtPolarMagnifier()
{
    delete m_data;
}
 
void QwtPolarMagnifier::setUnzoomKey( int key, int modifiers )
{
    m_data->unzoomKey = key;
    m_data->unzoomKeyModifiers = modifiers;
}
 
void QwtPolarMagnifier::getUnzoomKey( int& key, int& modifiers ) const
{
    key = m_data->unzoomKey;
    modifiers = m_data->unzoomKeyModifiers;
}
 
QwtPolarCanvas* QwtPolarMagnifier::canvas()
{
    return qobject_cast< QwtPolarCanvas* >( parent() );
}
 
const QwtPolarCanvas* QwtPolarMagnifier::canvas() const
{
    return qobject_cast< QwtPolarCanvas* >( parent() );
}
 
QwtPolarPlot* QwtPolarMagnifier::plot()
{
    QwtPolarCanvas* c = canvas();
    if ( c )
        return c->plot();
 
    return NULL;
}
 
const QwtPolarPlot* QwtPolarMagnifier::plot() const
{
    const QwtPolarCanvas* c = canvas();
    if ( c )
        return c->plot();
 
    return NULL;
}
 
void QwtPolarMagnifier::widgetKeyPressEvent( QKeyEvent* event )
{
    const int key = event->key();
    const int state = event->modifiers();
 
    if ( key == m_data->unzoomKey &&
        state == m_data->unzoomKeyModifiers )
    {
        unzoom();
        return;
    }
 
    QwtMagnifier::widgetKeyPressEvent( event );
}
 
void QwtPolarMagnifier::rescale( double factor )
{
    factor = qAbs( factor );
    if ( factor == 1.0 || factor == 0.0 )
        return;
 
    QwtPolarPlot* plt = plot();
    if ( plt == NULL )
        return;
 
    QwtPointPolar zoomPos;
    double newZoomFactor = plt->zoomFactor() * factor;
 
    if ( newZoomFactor >= 1.0 )
        newZoomFactor = 1.0;
    else
        zoomPos = plt->zoomPos();
 
    const bool autoReplot = plt->autoReplot();
    plt->setAutoReplot( false );
 
    plt->zoom( zoomPos, newZoomFactor );
 
    plt->setAutoReplot( autoReplot );
    plt->replot();
}
 
void QwtPolarMagnifier::unzoom()
{
    QwtPolarPlot* plt = plot();
 
    const bool autoReplot = plt->autoReplot();
    plt->setAutoReplot( false );
 
    plt->unzoom();
 
    plt->setAutoReplot( autoReplot );
    plt->replot();
}
 
#include "moc_qwt_polar_magnifier.cpp"