Docs: Swing guide doesn't work for \midi events

[madskjeldgaard]

The excellent Pattern cookbook's chapter on swing relies on using \timingOffset which does not seem to work with events of type \midi unfortunately because they don't use that key in the scheduling part of the event.

https://doc.sccode.org/Tutorials/A-Practical-Guide/PG_Cookbook08_Swing.html

This is what the midi event looks like in Event.sc:

midi: #{|server|
						var freqs, lag, dur, sustain, strum;
						var bndl, midiout, hasGate, midicmd;

						freqs = ~freq = ~detunedFreq.value;

						~amp = ~amp.value;
						~midinote = (freqs.cpsmidi).round(1).asInteger;
						strum = ~strum;
						lag = ~lag;
						sustain = ~sustain = ~sustain.value;
						midiout = ~midiout.value;
						~uid ?? { ~uid = midiout.uid };  // mainly for sysex cmd
						hasGate = ~hasGate ? true;
						midicmd = ~midicmd;
						bndl = ~midiEventFunctions[midicmd].valueEnvir.asCollection;

						bndl = bndl.asControlInput.flop;

						bndl.do {|msgArgs, i|
							var latency;

							latency = i * strum + lag;

							if(latency == 0.0) {
								midiout.performList(midicmd, msgArgs)
							} {
								thisThread.clock.sched(latency, {
									midiout.performList(midicmd, msgArgs);
								})
							};
							if(hasGate and: { midicmd === \noteOn }) {
								thisThread.clock.sched(sustain + latency, {
									midiout.noteOff(*msgArgs)
								});
							};
						};
					}

[telephon]

It would be great to have a UnitTest that checks midi event and note event equivalence!

[madskjeldgaard]

Yes that's a really great idea. At least my expectation as a user is for those two to be pretty much completely equivalent.

…

On 16 Feb 2023, at 23:01, Julian Rohrhuber ***@***.***> wrote: It would be great to have a UnitTest that checks midi event and note event equivalence! — Reply to this email directly, view it on GitHub <#5975 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AFLO64EW7ETGIXGWQQM2AUDWX2PSFANCNFSM6AAAAAAU6VT6IE>. You are receiving this because you authored the thread.

[smrg-lm]

I have seen this issue, it isn't related to the midi event implementation but the use of \timingOffset as a key, it doesn't exist except for \note events (and maybe other related events/streams that create the key or use the default event) and is ignored (returns nil or creates the key) for everything else. The key is also used by EventStreamPlayer through Quant (iirc) and other related timing methods, maybe it should be implemented for \midi events too. It's a difficult one.

[totalgee]

👍
I just came across this problem in the last week, too, that timingOffset does not work for \midi type Events (and it should!). There is the lag key that works to shift MIDI Events in time, but it doesn't know anything about the tempo so it's more of a pain to use without some Pfunc shenanigans, like this:

Pdef(\b, Pbind(\dur, 0.25, \degree, Pseq((0..7), inf), \lag, 0.125 / Pfunc{ thisThread.clock.tempo}) <> midi).play;
// instead of just writing:
Pdef(\b, Pbind(\dur, 0.25, \degree, Pseq((0..7), inf), \timingOffset, 0.125) <> midi).play