What's the difference between calling QWidget::update() and QWidget::repaint()?

[Momergil]

Hello!

In Qwt's QwtPlotCanvas' replot() method, one may either call QWidget::update() or QWidget::repaint() depending on the "immediate paint" configuration.

Is there any significant difference (specially in terms of performance) between using either one of those two methods apart from that QWidget::repaint() does his job immediately while QWidget::update() does not?


Thanks,

Momergil

[wysota]

repaint() performs an immediate repaint, update() schedules an event. This means that

for(int i=0;i<10;++i) repaint();

for(int i=0;i<10;++i) repaint();

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will do 10 repaints and

for(int i=0;i<10;++i) update();

for(int i=0;i<10;++i) update();

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will do one repaint.