Waveform

Supercollider live coding with Elixir

Installation

Install supercollider:

brew cask install supercollider

or point to the sclang executable with the SCLANG_PATH environment variable visible to your livebook instance.

In livebook in the setup block:

Mix.install([{:waveform, git: "https://github.com/rpmessner/waveform"}])

The Synth.play function will send messages to supercollider.

To play a note add a new section to your livebook with the following code:

alias Waveform.Synth

Synth.synth("d4")

alias Harmony.Chord
ii_V_I = [
  {Chord.get("min7", "d4"), 2},
  {Chord.get("7", "g5"), 2},
  {Chord.get("maj7", "c5"), 4}
]

progression = fn -> Enum.map(Stream.cycle(ii_V_I), fn {chord, beats} ->
    Synth.play chord, duration: beats, attack: 0.2, decay: 1
    Process.sleep beats
  end)
end

pid = spawn progression

You should be hearing a repeating ii V I chord progression!

To stop the progression from playing, evaluate the following:

Process.exit(pid, :kill)