C++ (Cpp) QwtScaleDiv::logScale Examples

Example #1

File: scalePicker.cpp Project: BackupTheBerlios/qtiplot-svn

int ScalePicker::maxLabelWidth(const QwtScale *scale) const
{
	QFontMetrics fm(scale->font());
	const QwtScaleDraw * scaleDraw=scale->scaleDraw ();
	const QwtScaleDiv 	scaleDiv=scaleDraw->scaleDiv();
	const double step_eps = 1.0e-6;
    int maxWidth = 0;

    for (uint i = 0; i < scaleDiv.majCnt(); i++)
    {
        double val = scaleDiv.majMark(i);

        // correct rounding errors if val = 0
        if ((!scaleDiv.logScale()) 
            && (qwtAbs(val) < step_eps * qwtAbs(scaleDiv.majStep())))
        {
            val = 0.0;
        }

        const int w = fm.boundingRect(scaleDraw->label(val)).width();
        if ( w > maxWidth )
            maxWidth = w;
    }

    return maxWidth;
}