ResInsight/ApplicationCode/UserInterface/RiuQwtPlotWheelZoomer.cpp
2019-09-06 10:57:22 +02:00

74 lines
2.8 KiB
C++

/////////////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2017- Statoil ASA
//
// ResInsight is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// ResInsight is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.
//
// See the GNU General Public License at <http://www.gnu.org/licenses/gpl.html>
// for more details.
//
/////////////////////////////////////////////////////////////////////////////////
#include "RiuQwtPlotWheelZoomer.h"
#include "qwt_plot.h"
#include <QEvent>
#include <QWheelEvent>
#define RIU_SCROLLWHEEL_ZOOMFACTOR 1.1
#define RIU_SCROLLWHEEL_PANFACTOR 0.1
//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RiuQwtPlotWheelZoomer::RiuQwtPlotWheelZoomer( QwtPlot* plot )
: QObject( plot )
, m_plot( plot )
{
plot->canvas()->installEventFilter( this );
}
//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void zoomOnAxis( QwtPlot* plot, QwtPlot::Axis axis, double zoomFactor, int eventPos )
{
QwtScaleMap scaleMap = plot->canvasMap( axis );
double zoomCenter = scaleMap.invTransform( eventPos );
double newMin = zoomCenter - zoomFactor * ( zoomCenter - scaleMap.s1() );
double newMax = zoomCenter + zoomFactor * ( -zoomCenter + scaleMap.s2() );
plot->setAxisScale( axis, newMin, newMax );
}
//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
bool RiuQwtPlotWheelZoomer::eventFilter( QObject* watched, QEvent* event )
{
QWheelEvent* wheelEvent = dynamic_cast<QWheelEvent*>( event );
if ( wheelEvent )
{
double zoomFactor = 1.0 / RIU_SCROLLWHEEL_ZOOMFACTOR;
if ( wheelEvent->delta() > 0 )
{
zoomFactor = RIU_SCROLLWHEEL_ZOOMFACTOR;
}
zoomOnAxis( m_plot, QwtPlot::xBottom, zoomFactor, wheelEvent->pos().x() );
zoomOnAxis( m_plot, QwtPlot::xTop, zoomFactor, wheelEvent->pos().x() );
zoomOnAxis( m_plot, QwtPlot::yLeft, zoomFactor, wheelEvent->pos().y() );
zoomOnAxis( m_plot, QwtPlot::yRight, zoomFactor, wheelEvent->pos().y() );
m_plot->replot();
emit zoomUpdated();
}
return false;
}