Nice contributions @Magneson. A virtual Cymascope is definitely on our to-do list! What are you referring to by a using a shader?
Have been making good progress with manipulating nodes of a 3D sphere via scaling (as you empathized) and will share results soon, however modeling sound wave phenomena would definitely be the holy grail for digital cymatics!
What are you planning to make? Cymatics and Oscilloscopes are perhaps better placed in a shader of some sorts. I at least haven't found a satisfactory way to emulate that in Vuo (that doesn't necessarily mean it doesn't exist). I see from the way you pose the question that you might attack the problem from the wrong angle though. As audio input is a one dimensional value from 0 - 1 it doesn't lend itself well to xy(z) manipulation in its raw form. What it does well however, is scaling. So if you start by making a circle/sphere, then you can apply the audio values as scaling for those points, either by adding/mulitplying lists, or by scaling the points that go into them.
I'm attaching two compositions I whipped up quickly to demonstrate two ways of doing it, although there are a lot more. I suspect that if you go into 3D space with them, the z-axis (provided the object has origin at 0,0,0) will be the best one to scale.
You have to think about the process/build list nodes as a self-containing loop. This means that the hold nodes needs to be triggered from the loop itself in order to avoid flicker/unintended behaviour. So in order to get it to work, you would have to trigger the orange hold nodes from the orange process list "process item" port. However, I don't think that the process list is the best suited tool to do the task if I understand the build correctly.
If you look at the picture, the Xs mark where signals enter or leave a loop without a hold node, which will make things go bonkers.
As far as I understand it, the process list is intended to use to change items, i.e. if you input a 3D point list, you should expect a changed 3D list output. So when you then want to create a list of color items based on the 3D point list, the build list is better suited. This way you can pull the info from the original list, and create a new color list based on the attributes you set. To make it react to both set values, and an animated value, you can use the logic nodes && (AND) or || (OR) to merge which points it should react to (although at increased resource usage).
For the discussion Is Within Box Get Color, I think the solution that you suggested, @Bodysoulspirit, would actually be more efficient. Rather than building a list of 3D objects and then extracting their colors to send as DMX, @Xavier dev can build a list of colors and use that list both for creating the 3D objects and for sending as DMX.>
Yes, actually, I followed your recommendations and work on this color list as the attached file. It's better that way.
On the issue of "node hold", I work on the idea of injecting 2 "process list" into an "Is within Box". Following the recommendations I placed the hold nodes to avoid the flicker. After several attempts, the problem does not seem to be solved in this configuration. Maybe I omitted a parameter or that the problem comes from elsewhere. Could you guard me on this subject, thank you.