Hi Brad--

Interesting Craig. Can you tell me about the demo. I can kinda understand creating notes. But, how does the sequencer understand time... and time signature?

Currently when you make a note it has a default duration of 250 milliseconds (and full volume, and MIDI channel one, and pitch C3). This is just so that you can make a note and immediately play it without having to tell it that stuff (although if you try to play a note without all the info it will refuse, and tell you which things aren't set).

Sequences have a default tempo of 120 beats (quarter-notes) per minute, and when you add a default note to a default sequence the note realizes that its relative duration is an eighth-note.

When you ask something to play, it schedules MIDI events for the appropriate times (typically "immediately"), using its own absolute duration. Sequences are basically streams of other events, with an optional concurrent event. You can nest sequences. If a sequence's primary event stream and it concurrent event are of different absolute durations, it loops the shorter of them to fill out the time.

You change event info with abbreviated phrases like "120 bpm" or "3 seconds" (similar to "kick"). They're short now just because they're faster to type in a live performance situation, but they could just as well be complete sentences (in any language, the finite-state machine doesn't care, see http://netjam.org/quoth/. Note that you can add states and leaves while the system is running.).

-C