Get a smooth curve

[beekeep]

Hi all

I draw a simple x=y curve and the curve is not smooth.

so i use :

Curve->setRenderHint(QwtPlotItem::RenderAntialiased);

Curve->setRenderHint(QwtPlotItem::RenderAntialiased);

To copy to clipboard, switch view to plain text mode 

but if there is more than 100 points in the curve it's not smooth

How can i do to obtain a smooth curve ?

thank to all