Hopefully I'm missing something, but it looks to me like QwtPointMapper::toImage() will never use threads.
I'm trying to plot a large number of points using a QwtPlotCurve with the Dots style. While stepping through the code in debug I noticed that QwtPointMapper::toImage skipped the QFuture/QtConcurrent code based on a preprocessor check, "#if QWT_USE_THREADS".
I don't see any way for this check to pass. The only define for QWT_USE_THREADS that I can find is at the top of qwt_point_mapper.cpp :
If QT_NO_QFUTURE isn't defined then QWT_USE_THREADS = 0, and if QT_NO_QFUTURE is defined then QWT_USE_THREADS is not defined. Either way it seems that a subsequent check, "#if QWT_USE_THREADS", will fail.Qt Code:
#if !defined(QT_NO_QFUTURE) #define QWT_USE_THREADS 0 #endifTo copy to clipboard, switch view to plain text mode
Am I misinterpreting the logic?
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