foo.py

from collections import deque
import sys
import time
import threading

import mido
import numpy as np
from orbitant import backend as midi
from orbitant.transport import START, STOP, CLOCK
import sounddevice as sd
import sunvox as sv
import sunvox.buffered


SIZE = 512
FREQ = 44100

SUNVOX_FILE = 'ticks.sunvox'


def main():
    clock_p = sv.buffered.BufferedProcess(size=SIZE, freq=FREQ)
    player_p = sv.buffered.BufferedProcess(size=SIZE, freq=FREQ)
    clock_slot = sv.Slot(process=clock_p)
    player_slot = sv.Slot(process=player_p)

    buf_len_seconds = SIZE / FREQ
    tick_events = deque()
    seq_tick_events = deque()

    ports = [
        midi.open_output('studiomux @ Cadence', virtual=False),
        midi.open_output('USB2.0-MIDI Port 2', virtual=False),
    ]

    def callback(outdata, frames, t, status):
        clock_buf = clock_p.fill_buffer()
        player_buf = player_p.fill_buffer()
        outdata[:] = np.tile(player_buf, outdata.shape[1] // 2)
        ticks, = (clock_buf.transpose()[0] != 0).nonzero()
        if ticks.any():
            last = None
            for tick in ticks:
                if last is None or tick - last > 1:
                    wait = buf_len_seconds * (tick / SIZE)
                    until = time.time() + wait
                    tick_events.append(until)
                    last = tick

    def clock():
        print('clock started')
        ticks = -1
        while True:
            if tick_events:
                e = tick_events.popleft()
                while time.time() < e:
                    time.sleep(0)
                for port in ports:
                    port.send(CLOCK)
                seq_tick_events.append(e)
                ticks += 1
                if ticks % 24 == 0:
                    sys.stdout.write('\n')
                sys.stdout.write('.')
                sys.stdout.flush()
            time.sleep(0)

    def sequencer():
        print('sequencer started')
        ticks = -1
        while True:
            if seq_tick_events:
                seq_tick_events.popleft()
                ticks += 1
                if ticks % 24 == 0:
                    player_slot.send_event(0, sv.NOTECMD.C4, 32, 3, 0, 0)
                    sys.stdout.write('C')
                else:
                    sys.stdout.write(' ')
                if ticks % 96 == 0:
                    player_slot.send_event(1, sv.NOTECMD.G3, 48, 3, 0, 0)
                    sys.stdout.write('G')
                else:
                    sys.stdout.write(' ')
                if ticks % 32 == 0:
                    sys.stdout.write('E')
                    player_slot.send_event(2, sv.NOTECMD.E4, 64, 3, 0, 0)
                else:
                    sys.stdout.write(' ')
                if ticks % 12 == 0:
                    sys.stdout.write('F')
                    player_slot.send_event(3, sv.NOTECMD.F4, 64, 3, 0, 0)
                else:
                    sys.stdout.write(' ')
                sys.stdout.flush()
            time.sleep(0)

    clock_thread = threading.Thread(None, clock, 'clock', daemon=True)
    clock_thread.start()

    sequencer_thread = threading.Thread(None, sequencer, 'sequencer', daemon=True)
    sequencer_thread.start()

    clock_slot.load(SUNVOX_FILE)
    player_slot.load(SUNVOX_FILE)
    clock_slot.play_from_beginning()
    for port in ports:
        port.send(mido.Message('songpos', pos=0))
        port.send(START)
    with sd.OutputStream(FREQ, SIZE, callback=callback):
        input()

    for port in ports:
        port.send(STOP)

    clock_p.kill()
    player_p.kill()


if __name__ == '__main__':
    main()