Peter M. Groen / openbr

/* -*- 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
 *****************************************************************************/

// vim: expandtab

#include <qlayout.h>
#include <qpen.h>
#include <qwt_plot.h>
#include <qwt_scale_widget.h>
#include <qwt_scale_draw.h>
#include "plotmatrix.h"

class PlotMatrix::PrivateData
{
public:
    PrivateData():
        inScaleSync( false )
    {
        isAxisEnabled[QwtPlot::xBottom] = true;
        isAxisEnabled[QwtPlot::xTop] = false;
        isAxisEnabled[QwtPlot::yLeft] = true;
        isAxisEnabled[QwtPlot::yRight] = false;
    }

    bool isAxisEnabled[QwtPlot::axisCnt];
    QVector<QwtPlot *> plotWidgets;
    mutable bool inScaleSync;
};

PlotMatrix::PlotMatrix( int numRows, int numColumns, QWidget *parent ):
    QFrame( parent )
{
    d_data = new PrivateData();
    d_data->plotWidgets.resize( numRows * numColumns );

    QGridLayout *layout = new QGridLayout( this );
    for ( int row = 0; row < numRows; row++ )
    {
        for ( int col = 0; col < numColumns; col++ )
        {
            QwtPlot *plot = new QwtPlot( this );
            layout->addWidget( plot, row, col );

            for ( int axis = 0; axis < QwtPlot::axisCnt; axis++ )
            {
                connect( plot->axisWidget( axis ),
                    SIGNAL( scaleDivChanged() ), SLOT( scaleDivChanged() ) );
            }
            d_data->plotWidgets[row * numColumns + col] = plot;
        }
    }

    updateLayout();
}

PlotMatrix::~PlotMatrix()
{
    delete d_data;
}

int PlotMatrix::numRows() const
{
    const QGridLayout *l = qobject_cast<const QGridLayout *>( layout() );
    if ( l )
        return l->rowCount();

    return 0;
}

int PlotMatrix::numColumns() const
{
    const QGridLayout *l = qobject_cast<const QGridLayout *>( layout() );
    if ( l )
        return l->columnCount();
    return 0;
}

QwtPlot* PlotMatrix::plot( int row, int column )
{
    const int index = row * numColumns() + column;
    if ( index < d_data->plotWidgets.size() )
        return d_data->plotWidgets[index];

    return NULL;
}

const QwtPlot* PlotMatrix::plot( int row, int column ) const
{
    const int index = row * numColumns() + column;
    if ( index < d_data->plotWidgets.size() )
        return d_data->plotWidgets[index];

    return NULL;
}

void PlotMatrix::enableAxis( int axis, bool tf )
{
    if ( axis >= 0 && axis < QwtPlot::axisCnt )
    {
        if ( tf != d_data->isAxisEnabled[axis] )
        {
            d_data->isAxisEnabled[axis] = tf;
            updateLayout();
        }
    }
}

bool PlotMatrix::axisEnabled( int axis ) const
{
    if ( axis >= 0 && axis < QwtPlot::axisCnt )
        return d_data->isAxisEnabled[axis];

    return false;
}

void PlotMatrix::setAxisScale( int axis, int rowOrColumn,
    double min, double max, double step )
{
    int row = 0;
    int col = 0;

    if ( axis == QwtPlot::xBottom || axis == QwtPlot::xTop )
        col = rowOrColumn;
    else
        row = rowOrColumn;

    QwtPlot *plt = plot( row, col );
    if ( plt )
    {
        plt->setAxisScale( axis, min, max, step );
        plt->updateAxes();
    }
}

void PlotMatrix::scaleDivChanged()
{
    if ( d_data->inScaleSync )
        return;

    d_data->inScaleSync = true;

    QwtPlot *plt = NULL;
    int axisId = -1;
    int rowOrColumn = -1;

    // find the changed axis
    for ( int row = 0; row < numRows(); row++ )
    {
        for ( int col = 0; col < numColumns(); col++ )
        {
            QwtPlot *p = plot( row, col );
            if ( p )
            {
                for ( int axis = 0; axis < QwtPlot::axisCnt; axis++ )
                {
                    if ( p->axisWidget( axis ) == sender() )
                    {
                        plt = p;
                        axisId = axis;
                        if ( axisId == QwtPlot::xBottom || axisId == QwtPlot::xTop )
                            rowOrColumn = col;
                        else
                            rowOrColumn = row;

                    }
                }
            }
        }
    }

    if ( plt )
    {

        // synchronize the axes
        if ( axisId == QwtPlot::xBottom || axisId == QwtPlot::xTop )
        {
            for ( int row = 0; row < numRows(); row++ )
            {
                QwtPlot *p = plot( row, rowOrColumn );
                if ( p != plt )
                    p->setAxisScaleDiv( axisId, plt->axisScaleDiv( axisId ) );
            }
        }
        else
        {
            for ( int col = 0; col < numColumns(); col++ )
            {
                QwtPlot *p = plot( rowOrColumn, col );
                if ( p != plt )
                    p->setAxisScaleDiv( axisId, plt->axisScaleDiv( axisId ) );
            }
        }

        updateLayout();
    }

    d_data->inScaleSync = false;
}

void PlotMatrix::updateLayout()
{
    for ( int row = 0; row < numRows(); row++ )
    {
        for ( int col = 0; col < numColumns(); col++ )
        {
            QwtPlot *p = plot( row, col );
            if ( p )
            {
                bool showAxis[QwtPlot::axisCnt];
                showAxis[QwtPlot::xBottom] =
                    axisEnabled( QwtPlot::xBottom ) && row == numRows() - 1;
                showAxis[QwtPlot::xTop] =
                    axisEnabled( QwtPlot::xTop ) && row == 0;
                showAxis[QwtPlot::yLeft] =
                    axisEnabled( QwtPlot::yLeft ) && col == 0;
                showAxis[QwtPlot::yRight] =
                    axisEnabled( QwtPlot::yRight ) && col == numColumns() - 1;

                for ( int axis = 0; axis < QwtPlot::axisCnt; axis++ )
                {
                    if ( axis == QwtPlot::xBottom || axis == QwtPlot::xTop )
                        p->enableAxis( axis, showAxis[axis] );
                    else
                    {
                        p->enableAxis( axis, true );

                        QwtScaleDraw *sd = p->axisScaleDraw( axis );
                        sd->enableComponent(
                            QwtScaleDraw::Backbone, showAxis[axis] );
                        sd->enableComponent(
                            QwtScaleDraw::Ticks, showAxis[axis] );
                        sd->enableComponent(
                            QwtScaleDraw::Labels, showAxis[axis] );
                    }
                }
            }
        }
    }

    for ( int col = 0; col < numColumns(); col++ )
    {
        alignVAxes( col, QwtPlot::yLeft );
        alignVAxes( col, QwtPlot::yRight );
    }

    for ( int row = 0; row < numRows(); row++ )
    {
        for ( int col = 0; col < numColumns(); col++ )
        {
            QwtPlot *p = plot( row, col );
            if ( p )
                p->replot();
        }
    }
}

void PlotMatrix::alignVAxes( int col, int axis )
{
    if ( axis != QwtPlot::yLeft && axis != QwtPlot::yRight )
        return;

    double maxExtent = 0;
    for ( int row = 0; row < numRows(); row++ )
    {
        QwtPlot *p = plot( row, col );
        if ( p )
        {
            QwtScaleWidget *scaleWidget = p->axisWidget( axis );

            QwtScaleDraw *sd = scaleWidget->scaleDraw();
            sd->setMinimumExtent( 0.0 );

            const double extent = sd->extent( scaleWidget->font() );
            if ( extent > maxExtent )
                maxExtent = extent;
        }
    }
    for ( int row = 0; row < numRows(); row++ )
    {
        QwtPlot *p = plot( row, col );
        if ( p )
        {
            QwtScaleWidget *scaleWidget = p->axisWidget( axis );
            scaleWidget->scaleDraw()->setMinimumExtent( maxExtent );
        }
    }
}