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26 lines
984 B
26 lines
984 B
3 years ago
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1) Incremental plots
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IncrementalPlot shows an example how to implement a plot that
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displays growing data.
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The example produces random data when you push the start button.
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With 'Timer' you can adjust the intervall between the
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the generation of the points, with 'Points' you can set the number
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of points to be generated.
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Unfortunately in Qt4 incremental painting is not possible with QPaintEngines
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that doesn't support the QPaintEngine::PaintOutsidePaintEvent feature.
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( These are all common paint engines beside the OpenGL engine, but this one
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is not supported by Qwt yet. )
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That is the reason why you can see much faster repaints with Qt3.
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2) Stacked Zooming with scrollbars
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ScrollZoomer adds scrollbars for zooming. There are a couple of
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reasons why the implementation is a hack and therefore the class
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is not part of the Qwt lib, but it should be working with all
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types of QwtPlots. Copy the code of scrollbar.[h|cpp] and
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scrollzoomer.[h|cpp] to the application code.
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Uwe
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