Hi,
I just wondered if anyone has tried rendering large datasets using jfreechart. I have datasets that that has 10 000 000 items. Since I have scrolling and zooming functionality I have to resample "on the fly" which takes a while... although I only render 2000 items.
What I do is:
1) Render only the items within the visible range (jfreechart code renders the whole dataset)
2) Resample if there are more than 2000 items within the visible area. (If actual number of items within the range I am rendering is below 2000, I am rendering the original samples instead (no resampling)).
I have found that the best resampling method is to render both the minimum and maximum value for each "sample range" as this is the only way it will look as if I am rendering the whole dataset.
Does anyone have suggestions on how to optimize the rendering of large datasets as it is quite slow since I have to resample all the time?