Unfixed Pbind duration

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4

This is a common request - good advice from @jamshark70.

It’s probably easier to experiment with this than one might expect… The core function in EventStreamPlayer, where new Events are pulled and the ESP is rescheduled, is prNext. The implementation is pretty readable… in particular, you can see where the next time is calculated, or where we bail out if we have a nil duration:

  nextTime = outEvent.playAndDelta(cleanup, muteCount > 0);
  if (nextTime.isNil) { this.removedFromScheduler; ^nil };
  nextBeat = inTime + nextTime;	// inval is current logical beat
  ^nextTime

Observe that, in general, Routine's can easily be restarted after a nil is returned:

r = Routine({ 
	[1, 1, nil, 2, 2].do {
		|i|
		i.postln;
		i.yield
	}
});    

r.play; // pauses after nil
r.play; // run this to begin playback again

If you want to experiment with custom scheduling / playback, just subclass EventStreamPlayer and override prNext to provide your own behavior. For example, you might try to allow events to use a Condition as \delta value, which could look something like this:

// Assuming we return an Event like: (delta: ~resume = Condition(false))
// We could then resume by doing ~resume.unhang() elsewhere.

	prNext { arg inTime;
		var nextTime;
		var outEvent = stream.next(event.copy);
		if (outEvent.isNil) {
			streamHasEnded = stream.notNil;
			cleanup.clear;
			this.removedFromScheduler;
			^nil
		}{
			nextTime = outEvent.playAndDelta(cleanup, muteCount > 0);
			if (nextTime.isKindOf(Condition)) {
				fork {
					nextTime.wait();   // wait for condition
				        nextTime = thisThread.beats; // reset time
					routine.play(); // and resume our routine....
                                };
				^nil  // This will stop our routine from resuming on the clock
			} {
				if (nextTime.isNil) { this.removedFromScheduler; ^nil };
				nextBeat = inTime + nextTime;	// inval is current logical beat
				^nextTime
			}
		};
	}

Of course, you can detect anything you want in your outEvent in order to do the “pause” behavior - you might have a special key, etc. I haven’t tested this, but I hope it’s a place to start for anyone that wants to experiment - please post if you have any interesting success (or failure)!

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