New Note `offset` parameter

[emuell]

We now have a glide note property in dev for an upcoming release. See: #74

Another basic, obvious addition, and contrary to glide, a relatively low hanging fruit, would be an offset command. It should be optional, just like glide, and should allow to set a sample/playback starting offset for the note. Using a relative value makes sense in our context, so that:

• o0.0 - starts from the beginning of the file/sound (same as not specifying it)
• o0.5 - starts from the middle of the file/sound.

Required changes:

• add new optional offset parameter to the rust Note representation
• add offset functions to Lua API note and sequence function and table constructors
• add o attribute to the Lua API note strings: note("c5 o0.1")
• add o attribute in cycles

Examples:

-- a hi-hat alike pattern with randomized sample offset values
return pattern {
  unit = "1/8",
  pulse = {0, 1, {1, 1}, 0, 1, {1, 1, 1}},
  event = function (context)
    if context.pulse_time < 1 then -- in all all sub-divided pulses
      return note("c5 v0.5"):offset(math.random() * 0.1)
    else
      return "c5"
    end
  end
}

Or in cycles:

-- Note ARP cycle with alternating offset values
cycle "[<c4 a3 d3>:o=<0.1 0.2>]*12"

---

It may be interesting to use other units than the relative ones, too. For example, c4 o1# to address cue/slice markers directly, just like in Renoise's S pattern command. This will not be very portable, though, and in Renoise, you can always map slices to notes as workaround.

Other units such as beats, seconds could be interesting as well: c4 o0.5b (0.5 beats), c4 o2s (2.0 seconds). This could be handled as an extra feature, after we got the basic relative value implementation ready. Those also won't be compatible with Renoise's pattern commands.

[Alexander-Zyurkalov]

About the glide parameter. Will it also affect midi-notes produced by the script when we pass the output to the MIDI output or a plugin in Renoise?

[emuell]

Unlikely. Good old MIDI only has pitch-bend, and pitch-bend ranges are not well defined or configurable. I guess it will be easier to e.g. play the synth in mono with legato here using two polyphone columns in the script.

It may be possible to use MPE for plugins here, but Renoise doesn't support MPE yet.

[Alexander-Zyurkalov]

But can't the pitch-bend be treated in the same way as in MPE? MPE is just MIDI where for each note we use a different channel. In the scripts we write channels manually, so it is kind of compatible with MPE already. So if we agree on rages for the pitch bend to match with MPE, it can work. Besides, users can always adapt the pitch bend by their needs at the output in a third-party modules or in the lua-script itself.

[emuell]

Could maybe work, yes. But I honestly don't think that's going to be worth the troubles on the implementation side when the result only works in specific well defined scenarios on the user side.

[Alexander-Zyurkalov]

Ah, I see. I will try to fork it then and implement myself. If you change your mind, we can merge it back. Though I don't know whether it would affect Renoise if I replace pattrn dynamic library with my own.

[emuell]

The pattrns engine only produces raw events using its own definition of events, as defined here: https://github.com/renoise/pattrns/blob/dev/src/event.rs — it's not using MIDI or some other portable format. It does not play them - it just generates them.

The playback engine (in this case Renoise) interprets and plays the generated events, and thus does whatever it can do with the provided note properties. So there's nothing to change in pattrns here, but only on the playback side.

You could, in theory, write your own playback engine, which transforms the pattrns events into raw MIDI events and send them in real-time to some device. Actually had thought about writing a simple MIDI player at some point, but didn't really see the need for it so far.

There's an example player at https://github.com/renoise/pattrns/blob/dev/src/player.rs#L566 which is using phonic a Rust based playback engine. It's used for the play and play-script examples as inspiration. It's a lot more complicated than a plain MIDI player would be, though.

[Alexander-Zyurkalov]

So there's no way to implement that on my end with the pattern engine, unfortunately :-(