How can I do none sample processing stuff?

Hi, I have an idea for a audio plugin and/or stand alone tool. I would like to know if I can do this using Juce. Therefore I have some questions. This is one of them:

In my project I will generate audio (time domain) samples based on some other calculations. These other calculation need to be done a lot, but are not sample (time domain) based.

How can I do that?
Is there a callback to do such processing?
Should I (ab)use the standard audio processing callback for this?
If so, is there some timer value available so that I can evenly divide my processor load over multiple callbacks?
Or can I create some new thread at plugin startup that does this kind of processing and link this somehow to the audio callbacks?