qwt_plot_axis.cpp

/* -*- 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.h"
#include "qwt_math.h"
#include "qwt_scale_widget.h"
#include "qwt_scale_div.h"
#include "qwt_scale_engine.h"

class QwtPlot::AxisData
{
public:
    bool isEnabled;
    bool doAutoScale;

    double minValue;
    double maxValue;
    double stepSize;

    int maxMajor;
    int maxMinor;

    QwtScaleDiv scaleDiv;
    QwtScaleEngine *scaleEngine;
    QwtScaleWidget *scaleWidget;
};

void QwtPlot::initAxesData()
{
    int axisId;

    for( axisId = 0; axisId < axisCnt; axisId++)
        d_axisData[axisId] = new AxisData;

    d_axisData[yLeft]->scaleWidget = 
        new QwtScaleWidget(QwtScaleDraw::LeftScale, this);
    d_axisData[yRight]->scaleWidget = 
        new QwtScaleWidget(QwtScaleDraw::RightScale, this);
    d_axisData[xTop]->scaleWidget = 
        new QwtScaleWidget(QwtScaleDraw::TopScale, this);
    d_axisData[xBottom]->scaleWidget = 
        new QwtScaleWidget(QwtScaleDraw::BottomScale, this);


    QFont fscl(fontInfo().family(), 10);
    QFont fttl(fontInfo().family(), 12, QFont::Bold);

    for(axisId = 0; axisId < axisCnt; axisId++)
    {
        AxisData &d = *d_axisData[axisId];

        d.scaleWidget->setFont(fscl);
        d.scaleWidget->setMargin(2);

        QwtText text;
        text.setFont(fttl);
        d.scaleWidget->setTitle(text);

        d.doAutoScale = true;

        d.minValue = 0.0;
        d.maxValue = 1000.0;
        d.stepSize = 0.0;

        d.maxMinor = 5;
        d.maxMajor = 8;

        d.scaleEngine = new QwtLinearScaleEngine;

        d.scaleDiv.invalidate();
    }

    d_axisData[yLeft]->isEnabled = true;
    d_axisData[yRight]->isEnabled = false;
    d_axisData[xBottom]->isEnabled = true;
    d_axisData[xTop]->isEnabled = false;
}

void QwtPlot::deleteAxesData()
{
    for( int axisId = 0; axisId < axisCnt; axisId++)
    {
        delete d_axisData[axisId]->scaleEngine;
        delete d_axisData[axisId];
        d_axisData[axisId] = NULL;
    }
}

const QwtScaleWidget *QwtPlot::axisWidget(int axisId) const
{
    if (axisValid(axisId))
        return d_axisData[axisId]->scaleWidget;

    return NULL;
}

QwtScaleWidget *QwtPlot::axisWidget(int axisId)
{
    if (axisValid(axisId))
        return d_axisData[axisId]->scaleWidget;

    return NULL;
}

void QwtPlot::setAxisScaleEngine(int axisId, QwtScaleEngine *scaleEngine)
{
    if (axisValid(axisId) && scaleEngine != NULL )
    {
        AxisData &d = *d_axisData[axisId];

        delete d.scaleEngine;
        d.scaleEngine = scaleEngine;

        d.scaleDiv.invalidate();

        autoRefresh();
    }
}

QwtScaleEngine *QwtPlot::axisScaleEngine(int axisId)
{
    if (axisValid(axisId))
        return d_axisData[axisId]->scaleEngine;
    else
        return NULL;
}

const QwtScaleEngine *QwtPlot::axisScaleEngine(int axisId) const
{
    if (axisValid(axisId))
        return d_axisData[axisId]->scaleEngine;
    else
        return NULL;
}
bool QwtPlot::axisAutoScale(int axisId) const
{
    if (axisValid(axisId))
        return d_axisData[axisId]->doAutoScale;
    else
        return false;
    
}

bool QwtPlot::axisEnabled(int axisId) const
{
    if (axisValid(axisId))
        return d_axisData[axisId]->isEnabled;
    else
        return false;
}

QFont QwtPlot::axisFont(int axisId) const
{
    if (axisValid(axisId))
        return axisWidget(axisId)->font();
    else
        return QFont();
    
}

int QwtPlot::axisMaxMajor(int axisId) const
{
    if (axisValid(axisId))
        return d_axisData[axisId]->maxMajor;
    else
        return 0;
}

int QwtPlot::axisMaxMinor(int axisId) const
{
    if (axisValid(axisId))
        return d_axisData[axisId]->maxMinor;
    else
        return 0;
}

const QwtScaleDiv *QwtPlot::axisScaleDiv(int axisId) const
{
    if (!axisValid(axisId))
        return NULL;

    return &d_axisData[axisId]->scaleDiv;
}

QwtScaleDiv *QwtPlot::axisScaleDiv(int axisId) 
{
    if (!axisValid(axisId))
        return NULL;

    return &d_axisData[axisId]->scaleDiv;
}

const QwtScaleDraw *QwtPlot::axisScaleDraw(int axisId) const
{
    if (!axisValid(axisId))
        return NULL;

    return axisWidget(axisId)->scaleDraw();
}

QwtScaleDraw *QwtPlot::axisScaleDraw(int axisId) 
{
    if (!axisValid(axisId))
        return NULL;

    return axisWidget(axisId)->scaleDraw();
}

QwtText QwtPlot::axisTitle(int axisId) const
{
    if (axisValid(axisId))
        return axisWidget(axisId)->title();
    else
        return QwtText();
}

void QwtPlot::enableAxis(int axisId, bool tf)
{
    if (axisValid(axisId) && tf != d_axisData[axisId]->isEnabled)
    {
        d_axisData[axisId]->isEnabled = tf;
        updateLayout();
    }
}

double QwtPlot::invTransform(int axisId, int pos) const
{
    if (axisValid(axisId))
       return(canvasMap(axisId).invTransform(pos));
    else
       return 0.0;
}


int QwtPlot::transform(int axisId, double value) const
{
    if (axisValid(axisId))
       return(canvasMap(axisId).transform(value));
    else
       return 0;
    
}

void QwtPlot::setAxisFont(int axisId, const QFont &f)
{
    if (axisValid(axisId))
        axisWidget(axisId)->setFont(f);
}

void QwtPlot::setAxisAutoScale(int axisId)
{
    if (axisValid(axisId) && !d_axisData[axisId]->doAutoScale )
    {
        d_axisData[axisId]->doAutoScale = true;
        autoRefresh();
    }
}

void QwtPlot::setAxisScale(int axisId, double min, double max, double stepSize)
{
    if (axisValid(axisId))
    {
        AxisData &d = *d_axisData[axisId];

        d.doAutoScale = false;
        d.scaleDiv.invalidate();

        d.minValue = min;
        d.maxValue = max;
        d.stepSize = stepSize;
            
        autoRefresh();
    }
}

void QwtPlot::setAxisScaleDiv(int axisId, const QwtScaleDiv &scaleDiv)
{
    if (axisValid(axisId))
    {
        AxisData &d = *d_axisData[axisId];

        d.doAutoScale = false;
        d.scaleDiv = scaleDiv;

        autoRefresh();
    }
}

void QwtPlot::setAxisScaleDraw(int axisId, QwtScaleDraw *scaleDraw)
{
    if (axisValid(axisId))
    {
        axisWidget(axisId)->setScaleDraw(scaleDraw);
        autoRefresh();
    }
}

#if QT_VERSION < 0x040000
void QwtPlot::setAxisLabelAlignment(int axisId, int alignment)
#else
void QwtPlot::setAxisLabelAlignment(int axisId, Qt::Alignment alignment)
#endif
{
    if (axisValid(axisId))
        axisWidget(axisId)->setLabelAlignment(alignment);
}

void QwtPlot::setAxisLabelRotation(int axisId, double rotation)
{
    if (axisValid(axisId))
        axisWidget(axisId)->setLabelRotation(rotation);
}

void QwtPlot::setAxisMaxMinor(int axisId, int maxMinor)
{
    if (axisValid(axisId))
    {
        if ( maxMinor < 0 )
            maxMinor = 0;
        if ( maxMinor > 100 )
            maxMinor = 100;
            
        AxisData &d = *d_axisData[axisId];

        if ( maxMinor != d.maxMinor )
        {
            d.maxMinor = maxMinor;
            d.scaleDiv.invalidate();
            autoRefresh();
        }
    }
}

void QwtPlot::setAxisMaxMajor(int axisId, int maxMajor)
{
    if (axisValid(axisId))
    {
        if ( maxMajor < 1 )
            maxMajor = 1;
        if ( maxMajor > 1000 )
            maxMajor = 10000;
            
        AxisData &d = *d_axisData[axisId];
        if ( maxMajor != d.maxMinor )
        {
            d.maxMajor = maxMajor;
            d.scaleDiv.invalidate();
            autoRefresh();
        }
    }
}

void QwtPlot::setAxisTitle(int axisId, const QString &title)
{
    if (axisValid(axisId))
        axisWidget(axisId)->setTitle(title);
}

void QwtPlot::setAxisTitle(int axisId, const QwtText &title)
{
    if (axisValid(axisId))
        axisWidget(axisId)->setTitle(title);
}

void QwtPlot::updateAxes() 
{
    // Find bounding interval of the item data
    // for all axes, where autoscaling is enabled
    
    QwtDoubleInterval intv[axisCnt];

    const QwtPlotItemList& itmList = itemList();

    QwtPlotItemIterator it;
    for ( it = itmList.begin(); it != itmList.end(); ++it )
    {
        const QwtPlotItem *item = *it;

        if ( !item->testItemAttribute(QwtPlotItem::AutoScale) )
            continue;

        if ( axisAutoScale(item->xAxis()) || axisAutoScale(item->yAxis()) )
        {
            const QwtDoubleRect rect = item->boundingRect();
            intv[item->xAxis()] |= QwtDoubleInterval(rect.left(), rect.right());
            intv[item->yAxis()] |= QwtDoubleInterval(rect.top(), rect.bottom());
        }
    }

    // Adjust scales

    for (int axisId = 0; axisId < axisCnt; axisId++)
    {
        AxisData &d = *d_axisData[axisId];

        double minValue = d.minValue;
        double maxValue = d.maxValue;
        double stepSize = d.stepSize;

        if ( d.doAutoScale && intv[axisId].isValid() )
        {
            d.scaleDiv.invalidate();

            minValue = intv[axisId].minValue();
            maxValue = intv[axisId].maxValue();

            d.scaleEngine->autoScale(d.maxMajor, 
                minValue, maxValue, stepSize);
        }
        if ( !d.scaleDiv.isValid() )
        {
            d.scaleDiv = d.scaleEngine->divideScale(
                minValue, maxValue, 
                d.maxMajor, d.maxMinor, stepSize);
        }

        QwtScaleWidget *scaleWidget = axisWidget(axisId);
        scaleWidget->setScaleDiv(
            d.scaleEngine->transformation(), d.scaleDiv);

        int startDist, endDist;
        scaleWidget->getBorderDistHint(startDist, endDist);
        scaleWidget->setBorderDist(startDist, endDist);
    }

    for ( it = itmList.begin(); it != itmList.end(); ++it )
    {
        QwtPlotItem *item = *it;
        item->updateScaleDiv( *axisScaleDiv(item->xAxis()),
            *axisScaleDiv(item->yAxis()));
    }
}

---