GUI events slow down long computations
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@engsml
300k points-odd is still a lot of points, though having no experience I don't know what to expect. I don't suppose your average end-user will notice each one of those. If you only add 1 in 10 of them you callprocessEvents()10 times fewer for the same responsiveness. So if you have a lot of points you could sample or average and it would all be a lot quicker. Though that's probably very naughty :) -
@JonB That's definitely a good point. I'll have to play around with the UX when I get everything working properly in the end :)
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@engsml
Hang on a minute. Let's look at your code, please:int arrSize = 4096; //for incrementing in intervals for(int i = 0; i < arr.size(); i += arrSize) //Plots in increments of 4096 plot(arr, (i + 4096));This passes first 0+4096, then 4096+4096, then 8192+4096, then....
void myClass::plot(QVector<QPointF> arr, int size) for(int i = begin; i < size; i++){arris always the original array. I presume (I'm not C++)beginis always 0.sizeis bigger (by 4096) every timeplotis called.Aren't you (re-)plotting more & more points --- specifically, all points from 0 up to where you have progressed to --- every time you call
plot()in your batches?? Or am I going loopy?Hi,
@JonB said in GUI events slow down long computations:
void myClass::plot(QVector<QPointF> arr, int size)
for(int i = begin; i < size; i++){arr is always the original array. I presume (I'm not C++) begin is always 0. size is bigger (by 4096) every time plot is called.
Nope, it's a copy, if you want to avoid useless copies, pass const references i.e.
void myClass::plot(const QVector<QPointF> &arr).In the case you only want to process items between two elements of the vector then pass the start and end iterator within your arrays.
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@engsml
I see there is a https://doc.qt.io/qt-5.9/qxyseries.html#append-2 which takes aQList<QPointF>. It may or may not be more efficient than you adding points one-at-a-time. Might be worth a try?@JonB I tried that, but it still caused the GUI to become unresponsive. I also tried a similar approach where I passed a QVector<QPointF> and did series->replace(); and that was also too slow for the function to handle. It seems the data is just too large for these functions. I considered passing the array in intervals instead of all at once for these functions, but ultimately decided it was already very similar to the function I already have.
