melrōse musical expression player

//go:build !wasm // +build !wasm package transport import ( "github.com/emicklei/melrose/notify" "gitlab.com/gomidi/midi/v2/drivers/rtmididrv/imported/rtmidi" ) func init() { Initializer = rtInitialize } func rtInitialize() { if notify.IsDebug() { notify.Debugf("transport.init: use RtmidiTransporter") } Factory = func() Transporter { return RtmidiTransporter{} } } type RtmidiTransporter struct{} func (t RtmidiTransporter) HasInputCapability() bool { return true } func (t RtmidiTransporter) DefaultOutputDeviceID() int { return 0 } func (t RtmidiTransporter) DefaultInputDeviceID() int { return 0 } func (t RtmidiTransporter) NewMIDIOut(id int) (MIDIOut, error) { out, err := rtmidi.NewMIDIOutDefault() if err != nil { return nil, err } err = out.OpenPort(id, "") if err != nil { return nil, err } return RtmidiOut{out: out, port: id}, nil } func (t RtmidiTransporter) NewMIDIIn(id int) (MIDIIn, error) { in, err := rtmidi.NewMIDIInDefault() if err != nil { return nil, err } err = in.OpenPort(id, "") if err != nil { return nil, err } // Ignore sysex, timing, or active sensing messages. in.IgnoreTypes(true, true, true) return RtmidiIn{in: in, port: id}, nil } func (t RtmidiTransporter) NewMIDIListener(in MIDIIn) MIDIListener { return newRtListener(in.(RtmidiIn).in) } type RtmidiOut struct { out rtmidi.MIDIOut port int } func (o RtmidiOut) WriteShort(status int64, data1 int64, data2 int64) error { return o.out.SendMessage([]byte{byte(status & 0xFF), byte(data1 & 0xFF), byte(data2 & 0xFF)}) } func (o RtmidiOut) Close() error { if notify.IsDebug() { name, _ := o.out.PortName(o.port) notify.Debugf("transport.RtmidiOut.Close: name=%s port=%d", name, o.port) } return o.out.Close() } type RtmidiIn struct { in rtmidi.MIDIIn port int } func (i RtmidiIn) Close() error { if notify.IsDebug() { name, _ := i.in.PortName(i.port) notify.Debugf("transport.RtmidiIn.Close: name=%s port=%d", name, i.port) } return i.in.Close() } type RtListener struct { *mListener midiIn rtmidi.MIDIIn } func newRtListener(in rtmidi.MIDIIn) *RtListener { lis := &RtListener{ midiIn: in, mListener: newMListener(), } // since l.midiIn.SetCallback is blocking on success, there is no meaningful way to get an error // and set the callback non blocking go func(l *RtListener) { if err := l.midiIn.SetCallback(l.handleRtEvent); err != nil { notify.Warnf("failed to set listener callback") } }(lis) return lis } func (l *RtListener) Start() { l.mutex.Lock() defer l.mutex.Unlock() if l.listening { return } l.listening = true } func (l *RtListener) handleRtEvent(m rtmidi.MIDIIn, data []byte, delta float64) { if !l.listening { // consume event so the queue does not fill up // if notify.IsDebug() { // notify.Debugf("handle.rt.event:%v,%v\n", data, delta) // } return } if len(data) != 3 { return } status := int16(data[0]) nr := int(data[1]) data2 := int(data[2]) l.HandleMIDIMessage(status, nr, data2) } func (l *RtListener) Stop() { l.mutex.Lock() defer l.mutex.Unlock() if l.listening { if err := l.midiIn.CancelCallback(); err != nil { notify.Warnf("failed to cancel listener callback") } } l.listening = false }