func main() {
var (
id = flag.Int("id", -1, "MIDI output device ID (-1 = default)")
bpm = flag.Int("bpm", 120, "default BPM")
)
flag.Parse()
log.SetFlags(0)
portmidi.Initialize()
defer portmidi.Terminate()
deviceID := *id
if deviceID < 0 {
deviceID = portmidi.GetDefaultOutputDeviceID()
}
stream, err := portmidi.NewOutputStream(deviceID, bufferSize, latency)
if err != nil {
log.Fatalf("NewOutputStream(device ID %d, buffer size %d, latency %v): %v", deviceID, bufferSize, latency, err)
}
defer stream.Close()
var (
pulsePerSec = (float64(*bpm) / 60.) * 24.
interval = (1. / pulsePerSec) * float64(time.Second)
quitc = make(chan struct{})
)
defer close(quitc)
go func() {
log.Printf("%d BPM = %.2f PPS", *bpm, pulsePerSec)
defer log.Printf("done")
tick := time.Tick(time.Duration(interval))
for {
select {
case <-quitc:
return
case <-tick:
stream.Write([]portmidi.Event{{Timestamp: portmidi.Time(), Status: 0xF8}})
}
}
}()
sigc := make(chan os.Signal)
signal.Notify(sigc, syscall.SIGINT)
log.Print(<-sigc)
}
func main() {
var (
inID = flag.Int("in", -1, "MIDI input device ID (-1 = default)")
outID = flag.Int("out", -1, "MIDI output device ID (-1 = default)")
)
flag.Parse()
log.SetFlags(0)
portmidi.Initialize()
defer portmidi.Terminate()
if *inID < 0 {
(*inID) = portmidi.GetDefaultInputDeviceID()
}
if *outID < 0 {
(*outID) = portmidi.GetDefaultOutputDeviceID()
}
in, err := portmidi.NewInputStream(*inID, bufferSize)
if err != nil {
log.Fatalf("input stream (device ID %d, buffer size %d): %v", *inID, bufferSize, err)
}
out, err := portmidi.NewOutputStream(*outID, bufferSize, latency)
if err != nil {
log.Fatalf("output stream (device ID %d, buffer size %d, latency %v): %v", *outID, bufferSize, latency, err)
}
chain := markov.Chain{}
board := keyboard.Keyboard{}
first := true
prev := keyboard.Keyboard{}
log.Printf("listening for events...")
for inEvent := range in.Listen() {
log.Printf("-> %#+v", inEvent)
board.Receive(inEvent)
log.Printf("== %#+v", board.Keys())
if first {
prev = board
first = false
continue
}
chain.Observe(prev, board)
output := chain.Emit(board).(keyboard.Keyboard)
log.Printf("<- %#+v", output.Keys())
prev = board
outKeys := output.Keys()
if len(outKeys) == 0 {
// Can't send, will crash
// TODO needs attention
continue
}
if inEvent.Data2 == 0 {
// don't play notes on key up
continue
}
events := make([]portmidi.Event, len(outKeys))
for i, key := range outKeys {
events[i] = portmidi.Event{
Timestamp: inEvent.Timestamp,
Status: inEvent.Status,
Data1: int64(key),
Data2: inEvent.Data2,
}
}
out.Write(events)
}
}