QChart realtime performance
-
@jsulm Thanks for your reply. 400pts means reveiving 400 data points per second for each series.
@jiong You should not try to update the chart 400 times per second as it does not make sense. Instead do it like 24-60 times per second.
-
@jiong You should not try to update the chart 400 times per second as it does not make sense. Instead do it like 24-60 times per second.
-
@jiong You should not try to update the chart 400 times per second as it does not make sense. Instead do it like 24-60 times per second.
-
@jsulm
Could you kindly explain why you say "as it does not make sense", rather than, say, "it is not efficient"?@JonB What is the point to update the chart 400 times per second if the refresh rate of the display is 60Hz? A movie has typically a refresh rate of 24Hz - for human eye this is already smooth.
-
@JonB What is the point to update the chart 400 times per second if the refresh rate of the display is 60Hz? A movie has typically a refresh rate of 24Hz - for human eye this is already smooth.
-
@jsulm Fine, that's what I thought you had in mind. [FWIW, apes apparently have vastly faster image perception, so they might appreciate the 60 times per second ;-) ]
@JonB Well, if you develop apps for apes then you should consider this :-)
-
@jsulm Till the OP specifies otherwise, I assume a Qt app's audience potentially includes any sentient being.... For all I know his app is part of experimental animal research. :) I have watched orang-utans interacting with PC screens at Washington DC Zoo...
-
@jsulm Till the OP specifies otherwise, I assume a Qt app's audience potentially includes any sentient being.... For all I know his app is part of experimental animal research. :) I have watched orang-utans interacting with PC screens at Washington DC Zoo...
@JonB But then you would need a display which can actually refresh that fast.
-
@jsulm Which is why I said they might appreciate the 60 times per second rather than the 24. Though not the 400.
[Incidentally, have a look at https://books.google.co.uk/books?id=r4xywWpmXSEC&pg=PA15&lpg=PA15&dq=ape+vision+speed&source=bl&ots=ZGKKPG_adk&sig=qOypYm-Pg8rVfpsZ3hvdkMOR_2k&hl=en&sa=X&ved=0ahUKEwiOs8eu2tXbAhVrLcAKHVefAgQQ6AEIjAEwDw#v=onepage&q&f=true for just how much work is being done for ape-communication with software!]
I didn't mean to hijack this thread. I think the OP is still awaiting a further answer for:
@jiong
But, I have another problem, how could I update all the 24 series in a signle operation and cause a single repaint of the chart? -
@jsulm Thanks for your great suggestion. It's better when I tried your method. But, I have another problem, how could I update all the 24 series in a signle operation and cause a single repaint of the chart?
Thanks again.
@jiong said in QChart realtime performance:
. But, I have another problem, how could I update all the 24 series in a signle operation and cause a single repaint of the chart?
You should have a read of https://stackoverflow.com/questions/38804179/how-to-repaint-a-qchart for your situation (which, incidentally, "append points at 400000 pts/sec", making your speed look trivial!).
