An oscilloscope is a type of electronic test instrument that allows observation of constantly varying signal voltages, usually as a two-dimensional plot of one or more signals as a function of time. Non-electrical signals (such as sound or vibration) can be converted to voltages and displayed.
Jerobeam Fenderson created a FAQfor you who need to know more:
Now show us how to draw that butterfly!
How do you make 3D graphics with audio waveforms?
Some things (particularly spiral based ones, like the mushrooms) just come out looking like 3D objects without further ado.
For cubes, grids, pyramids, etc I generate 3-channel audio and run it through a Pd patch that converts it to 2 channels with a little bit of maths. An audio rendering engine, so to speak.