I apologize if this has already been addressed but this was determined as a issue years ago and forced us to implement a workaround.
We use PloXY for large data sets (up to 16 MB has become pretty standard lately). To address lag years ago, we pared the data to be viewed to 4000 data points in background code and send that to PlotXY. However, when the user zooms - which is always, you must then go back to the original data to find the new best 4K data points prior to plotting the new data. The code usually works well but there are instances where it can shutdown unexpectedly - not often enough to fight through friutfully though.
As for an truly automated perhaps a more logical course of action is to retrieve the panel size and use that for the data sizing. Regardless, it would be nice to use the CVI built in function and then subsequent zooming etc could be possible via standard functions.
