Hi Infragistics Support,
Can you provide some guidance/tips/suggestions for a new user of your controls?
I have a requirement to display ~400 series. Each with ~6000 points (for a total of ~2,400,000 points). Will Infragistics WPF chart control be able to handle this and still provide a good user experience?
Some other requirements: will need zoom and pan, Series hit testing but not necessarily point (marker) hit testing. I believe the data will normally be evenly spaced in the X direction but cannot guarantee that.
How would Infragistics recommend charting this data to achieve a good user experience (i.e. the char is still "snappy")?
Please let me know if any more information would help. Thanks!
Chris
Hey Chris,
This one is an interesting challenge! XamDataChart is very much tuned toward rendering complex visuals (a single line with 2 million points, for example) with great performance, but when you start throwing in an extreme number of visuals then the underlying platform (WPF, in this case) starts to show some strain, or, in some cases, you start hitting some areas of the chart hard that haven't been tuned as aggressively as others.
WPF really doesn't appreciate scenarios where there are many many visuals in the visual tree, which makes this sort of scenario a big challenge. However there are things you can do to arrange this scenario such that it performs well, I believe.
First of all, though, you may want to reconsider the requirement? What story is being told by having that many series present at once? Are you trying to show the shape of many overlapping data sets? In which case, it may be more useful to coalesce the data into a single, or multiple min/max data sets and plot them as RangeAreaSeries, which can show a min/max range. You could even use this in a hybrid scenario whereby you switch to showing the individual series once the user has zoomed in to a sufficient level. I realize, however, that this may not fit your requirements perfectly.
Here's some stuff you can do to tune the scenario where an extreme number of series are present:
With the above advice combined, your scenario seems to perform pretty well for me. Here's a gist with the code I was using (minus, disabling the mouse wheel):
https://gist.github.com/gmurray81/9a4fbcb71af824c51716
Hope this helps! Let me know if you have any other questions.
-Graham
Hi Graham,
Thanks for the quick response. A bit of detail - we're displaying the data acquired from a scientific instrument that collects signal from a "plate" of 396 wells over time. Each series represent the amount of fluorescence detected in each well on the plate. Once the data is captured, the scientists need to see all signal data at once to pick out what they are looking for. But once the data is acquired - it will never change.
I had already deduced a couple of your suggestions (the markers and legend) and we don't have much else in the charts airspace. (We have to add a dozen or so widgets to mark some peaks on one of the curves (some issues here which I will post about later if we stay with Infragistics) but that doesn't seem to cause any issues.)
I did not know about the bitmap caching mode and turned that on. Can't see too much of a difference with that tweak. When I get some more time I will play with the mouse wheel and panning suggestions.
I noticed in your sample code you are using a LineSeries. We're using a ScatterLineSeries. Would that make much of a difference performance wise? We could certainly use LineSeries if the X data is evenly spaced (which it will be most of the time) and when it isn't throw in the odd ScatterLineSeries to handle it.... thoughts?
Thanks for the advice! :)
Chris,
I've got something neat for you here: https://gist.github.com/gmurray81/52776872c9cdac3a6efb
Please note this also requires a generic.xaml (included in the gist) that you'll need to set up in the project that you add OrderedScatterLineSeries to. The easiest thing to do to get this set up is to do an Add New Item in VS and select WPF => Custom Control and add one to your project called OrderedScatterLineSeries. This will add the Generic.Xaml to your project and make sure that is all set up correctly. You should then be able to use the stuff from the gist.
The gist is an old sample I dug up that I wrote quote a while ago which implements a custom scatter line series which assumes more constraints on the data provided to it. I also tweaked it a bit more for your scenario, and fixed a few bugs. You should be able to drop it in as a replacement for ScatterLineSeries in your sample and comment out the lines that relate to the markers (this series doesn't support those as of yet). You should see its a lot smoother than ScatterLineSeries, and maybe even a bit smoother than LineSeries.
Now, you can also try setting UseHairline=true on that series (added this just for you). This will lower the fidelity a tad, but will make things even smoother. Normally this custom series, and the series built into the chart, are trying to simplify the line somewhat, but they want to make sure to represent the data faithfully, so what they actually end up drawing is a polygon that spans the min/max y values. Specifying UseHairline=true on this custom series will make sure that it only every uses a Polyline to render the series, and if the data points are especially dense in a region, it will only actually represent the max values, rather than spanning both the min and max values over that range. Let me know if I should elaborate further there.
Anyhow, this decreases the complexity of the visuals we are passing to WPF quite a bit so can boost things more for you, at the sacrifice of a bit of fidelity. The line will still make sure to encompass your max values in that mode, but doesn't necessarily encompass the min peaks. Anyhow, for greater fidelity you can leave that off. And in either case case, if you zoom in, you'll see all the data.
To decrease fidelity even further, to boost perf, you can start playing with the resolution setting on this series, or the built in chart series. Raising that to higher values will decrease fidelity further, but simplify the visuals pushed to WPF.
Try all the above with BitmapCache on or off, I'm not sure if it will help or hinder you with your scenario. Basically turn it on if the scenario you have set up seems to be slowing down the crosshair/tooltip/etc in addition to the zoom performance.
Hope this helps!
Hi Graham.
This looks cool. I'm deep in the bowels of coding up a module to read NetCDF scientific data files right now so I can't get to this right away. Hopefully this afternoon (I'm in the PST timezone) I'll be able to get to it. If not, Monday. I'll let you know how it goes.
Neat, let me know how it goes!
I've gotten a chance to look at what you posted WRT the OrderedScatterLineSeries. First off, thanks again for working with me. Let me know who I should email to give you some public praise! :)
So with the new series type. Seems to be working. :) I can see/feel an improvement in responsiveness. Especially WRT drag zooming. Of course this is all subjective but it does feel faster. We like the hairline so that is a plus. The BitmapCache on/off makes a big difference in performance so we'll stay with it on. In my (limited) playing with the Resolution setting, I found that the loss of resolution was too much for any gains in performance - even going from 1 to 2 I saw smooth peaks going to sharp peaks. And since we're interested in peaks.... that wasn't what we needed so we'll probably stay away from changing that.
So to wrap up, I think we'll stick with your enhancement. At some point soon, I'll try to get to your suggestions page to add this as an enhancement.
Awesome, glad I could help! Do let me know if you need any more assistance.
One note on the hairline mode, if you guys are also interested in negative peaks, you may want to alter the behavior whereby rather than it picking the min or max as the representative points for a range that it could first compute the median value for the series data, and select either min or max at any given point in time based on whether you are greater or less than the median, and maybe that will ensure that the maxima and minima are well represented.
As for praise, totally not required, just glad I could help! I'll make sure to send my manager this forum thread, though. I believe there is an opportunity to share feedback when we close a case, whether it positive or negative, but I'm not super familiar with the process, myself.
Thanks for further suggestions. We're good with peaks and such - we've got our own library to do all the "heavy lifting" math on the data - we'll just be adding a dozen or so annotations to the chart at the proper places (I will be raising an issue with this later though...).