Exemplo n.º 1
0
//--------------------------------------------------------------------------------------------------
/// 
//--------------------------------------------------------------------------------------------------
QPointF RiuSummaryQwtPlot::closestCurvePoint(const QPoint& cursorPosition, QString* valueString, QString* timeString, int* yAxis) const
{
    QPointF samplePoint;

    QwtPlotCurve* closestCurve = nullptr;
    double distMin = DBL_MAX;
    int closestPointSampleIndex = -1;

    const QwtPlotItemList& itmList = itemList();
    for (QwtPlotItemIterator it = itmList.begin(); it != itmList.end(); it++)
    {
        if ((*it)->rtti() == QwtPlotItem::Rtti_PlotCurve)
        {
            QwtPlotCurve* candidateCurve = static_cast<QwtPlotCurve*>(*it);
            double dist = DBL_MAX;
            int candidateSampleIndex = candidateCurve->closestPoint(cursorPosition, &dist);
            if (dist < distMin)
            {
                closestCurve = candidateCurve;
                distMin = dist;
                closestPointSampleIndex = candidateSampleIndex;
            }
        }
    }

    if (closestCurve && distMin < 50)
    {
        samplePoint = closestCurve->sample(closestPointSampleIndex);

        if (yAxis) *yAxis = closestCurve->yAxis();
    }


    if (timeString)
    {
        const QwtScaleDraw* timeAxisScaleDraw = axisScaleDraw(QwtPlot::xBottom);
        if (timeAxisScaleDraw)
        {
            *timeString = timeAxisScaleDraw->label(samplePoint.x()).text();
        }
    }

    if (valueString && closestCurve)
    {
        const QwtScaleDraw* yAxisScaleDraw = axisScaleDraw(closestCurve->yAxis());
        if (yAxisScaleDraw)
        {
            *valueString = yAxisScaleDraw->label(samplePoint.y()).text();
        }
    }

    return samplePoint;
}