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Thread: [Performance] Wide scale when drawing curves in plot

  1. #1
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    Default [Performance] Wide scale when drawing curves in plot

    I tried to draw some curves using QwtPlot, the scale of plot may range from 100 to 100000 pixels. It is easy to obtain this goal, but this solution consumes too much memory cause the size of plot too big.

    I think we can just draw part of curves, which display on screen. Now another problem arises, I don't know how to set scrollbar to control the display of curves.

    Any suggestions? Thanks in advance!

  2. #2
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    Default Re: [Performance] Wide scale when drawing curves in plot

    Have a look at the realtime example - here an optional scrollbars appear, when you zoom in. The implementation used in the example doesn't create any huge widgets and therefore doesn't run into the issues you mentioned above.

    IMHO having a widget of a width of 100000 pixels ( all kind of widgets not only QwtPlot ) is something you should avoid by any means.

    Uwe

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