Drawing lines with particles or geometry

I’m new to TD and would like to create an effect that basically graphs values over time. I have tried the feedback technique with a moving 3D object like outlined here [url]https://matthewragan.com/2013/06/15/vizualizing-osc-data-touchdesigner-2/[/url] but the end result has gaps in the line. It’s also not a pretty effect when the data changes quickly (more stepping in the feedback effect). I have also tries emitting some particles from a vertically moving ball that is linked to my data (with some forces blowing the particles on the x) but the performance drops to a crawl when the particles are given a longer lifetime.

Are there some other techniques that I can look into ? The effect needs to be as interactive as possible and have some interesting styling potential.

Run your values through a Trail CHOP. This will give you multisample channels that plot values over a chosen time range. If you want to make 3D line paths I suggest Limit SOPs.

derivative.ca/wiki088/index … =Limit_SOP

The Trail Channels will each represent one dimension of your 3D lines, let’s say it’s the Y dimension, X is time, and Z is nothing. Limit SOP needs tx, ty, and tz, so you’ll need to create those channels to get the desired result. To do this I usually use Pattern CHOPs to generate ramps (you can rename the output to be tx and tz on the Channel page of Pattern parameters). Your tx ramp would go from 0 to 1 (or whatever x coordinates you want) and tz from 0 to 0 (a flat line). If you plug your Trail CHOP output in to the Pattern CHOP inputs, the Pattern CHOPs will output channels of the same length as your Trails. Use a Merge CHOP to combine your new tx and tz channels with your value trails. To be neat, put a Null CHOP after the Merge

Now you can use your Trail channels to draw 3D lines with Limit SOPs. For each line you want to draw, add a Limit SOP and drop your Null into the CHOP parameter. For the x and z channels select your tx and tz, and for your y, select one of the values you wish to graph.

At this point you should have a bunch of lines representing your values over time. You can output them from Limit SOPs as simple lines, tubes, etc, or use those lines as source geometry for whatever you want.

I hope that makes sense. I’ve had a long week…

Thanks a lot for the tip, I will give it a try on Monday when I’m back at the computer where I have TD.

So i’m a little confused about how the pattern and merge nodes are supposed to function. My pattern CHOP just shows tx tz as two static curves. When I plug that into the merge CHOP, I get the same two channels in the display. Limit node just draws a a sloped line. I’m pretty sure there is some crucial bit I missed. All this is being driven by a wave at the moment so I should be getting some oscillating, am I right ?

Here is an example.
PlotValuesOverTime.3.toe (19.2 KB)

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