Using Radiant Voices to create a simple arpeggiator MetaModule for SunVox

simple_arp_metamodule.py

from pathlib import Path

from rv.api import m, Note, NOTE, Pattern, Project, Synth


if __name__ == "__main__":
    # Metamodules contain a project.
    project = Project()

    # Simple routing of a multisynth to a generator to output.
    project += (multisynth := m.MultiSynth())
    project += (generator := m.AnalogGenerator())
    multisynth >> generator >> project.output

    # Keep them from being visually stacked.
    project.layout()

    # Create an arpeggiator pattern.
    project += (pattern := Pattern("arp", tracks=1, lines=3, x=0))
    # (Setting `module` could use a nicer API)
    pattern.data[0][0] = Note(note=NOTE.C5, module=multisynth.index + 1)
    pattern.data[1][0] = Note(note=NOTE.E5, module=multisynth.index + 1)
    pattern.data[2][0] = Note(note=NOTE.G5, module=multisynth.index + 1)

    # Wrap the project in a metamodule, configured to play the arpeggiator.
    metamodule = m.MetaModule(project=project)
    metamodule.input_module = 256  # prevent incoming notes from directly triggering the MultiSynth
    metamodule.play_patterns = metamodule.PlayPatterns.on_repeat
    metamodule.arpeggiator = True

    # Expose the relative-note controller of the multisynth.
    # (This part could use a nicer API with fewer footguns.)
    #
    # Set the number of user-defined controllers.
    metamodule.user_defined_controllers = 1
    # Set the label of the first user-defined controller.
    controller = metamodule.user_defined[0]
    controller.label = "Relative Note"
    # Map the user-defined controller to the actual controller.
    mapping: m.MetaModule.Mapping = metamodule.mappings.values[0]
    mapping.module = multisynth.index
    mapping.controller = multisynth.controllers["transpose"].number - 1

    # Wrap the metamodule in a synth.
    synth = Synth(metamodule)

    # Save to a file.
    with Path("simple_mm.sunsynth").open("wb") as f:
        synth.write_to(f)