Re: Node Parameter Control using Curves

On Mon, Oct 4, 2010 at 1:38 PM, Joseph Berkovitz <joe@noteflight.com> wrote:

> Chris,
>
> I think that the overall approach you outline here does make sense.  There
> are a bunch of detailed issues regarding types of curves, etc. which I'll
> respond to elsewhere.
>
> One issue here is what the timing attaches to:
>
> Is it (as you proposed):
>
>
>    gainNode.gain.scheduleAutomation(fadeInCurve, now + 1.0);
>    source.noteOn(now + 1.0);
>
> or:
>
>    gainNode.gain.scheduleAutomation(fadeInCurve);
>    fadeInCurve.noteOn(now+1.0);
>
>    source.noteOn(now + 1.0);
>

I think I chose the first approach because the same automation curve may
then be shared across multiple "note" instances, where they're not all
triggered at the same time.


>
> The latter approach feels like a more consistent treatment of audio and
> modulation sources in some ways.  And that has advantages of its own -- any
> audio node could act as a modulator/automator.  Perhaps this would allow the
> use of a JavaScriptAudioNode as the source of a modulation/automation
> signal.
>

I think either way we could find some way to make this work, but I think it
may be tricky if we decide to mix the idea of control signal vs. audio
signal.  I'm not necessarily against the idea, but I think the API could be
challenging to design in a clean way.



> But the correct answer might be "neither of the above".  I will be writing
> up some thoughts on time sequencing issues shortly, because I'm a little
> troubled by the idea of noteOn() as the only way that things get
> choreographed in the API.  I also love noteOn() at the same time.  Anyway,
> I'll explain elsewhere...
>
> Also, terminology.  To be a bit fussy, I favor calling this sort of thing
> "modulation" rather than "automation" because it is more general.
>  Automation relates to a mixdown type of usage like moving a fader, but
> modulation is more generally a signal that affects some parameter value in
> real time.  Music synthesis tends to be more about modulation than
> automation -- vibrato, crescendo, guitar note bends, etc.  These act within
> a single musical event (often a single note), rather than across a bunch or
> a stream of events.


"modulation" sounds fine to me.  I'm not that attached to "automation".