Chord placement to follow; need not be pre-sorted.
Key/scale context, used for diatonic approach tones in walking.
OptionaltsTime signature; used for metric accents.
OptionalstyleBass-line idiom.
OptionaloctaveTarget register as a base MIDI octave; roots land around octave*12+12.
OptionalseedSeed for the deterministic PRNG.
Options controlling generateBassLine.