QwtPlotPicker and QwtPlotDirectPainter causes bolding of text

Hi,

I use QwtPlotDirectPainter:: DrawSeries to graph a curve in realtime. I use QwtPlotPicker to view the coordinates alongside the cursor on the graph. It would appear that using QwtPlotDirectPainter:: DrawSeries in conjunction with QwtPlotPicker causes the coordinates displayed alongside the cursor to continuously be written, resulting in the coordinates alongside the cursor appearing bold and not sharp when the cursor is kept still. This can be avoided if rather then using QwtPlotDirectPainter:: DrawSeries, I use replot. Is there any other way to avoid this, or is this inherent in using QwtPlotDirectPainter:: DrawSeries?

Thanks.