- Member QwtPlot::clear ()
- Use QwtPlotDeict::detachItems instead
- Class QwtPlotPrintFilter
- In Qwt 5.0 the design of QwtPlot allows/recommends writing individual QwtPlotItems, that are not known to QwtPlotPrintFilter. So this concept is outdated and QwtPlotPrintFilter will be removed/replaced in Qwt 6.x.
