/// <summary>
/// Callback function to be called by the system.
/// </summary>
/// <param name="handle">An <see cref="API.MidiDeviceHandle"/> to the MIDI input device to associate with the callback function.</param>
/// <param name="message">An <see cref="API.MidiInputMessage"/> containing the message.</param>
/// <param name="instance">An <see cref="IntPtr"/> to the instance data supplied by the <see cref="API.OpenMidiInputDevice"/> function.</param>
/// <param name="messageParameterA">An <see cref="IntPtr"/> to the first message parameter.</param>
/// <param name="messageParameterB">An <see cref="IntPtr"/> to the second message parameter.</param>
private void Callback(API.MidiDeviceHandle handle, API.MidiInputMessage message, IntPtr instance, IntPtr messageParameterA, IntPtr messageParameterB)
{
switch (message)
{
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_DATA:
// A = Packed MIDI message, B = Time in milliseconds since Start
ProcessShortMessage(new ShortMessage(messageParameterA, messageParameterB));
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_LONG_DATA:
// Extracts the MIDI header for message validation
API.MidiHeader midiHeader = (API.MidiHeader)Marshal.PtrToStructure(messageParameterA, typeof(API.MidiHeader));
// Prevents creation of long messages when the MIDI header buffer is empty
if (midiHeader.BytesRecorded == 0)
{
ReleaseBuffer(messageParameterA);
return;
}
// A = Pointer to MIDI header, B = Time in milliseconds since Start
ProcessLongMessage(new LongMessage(messageParameterA, messageParameterB));
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_MORE_DATA:
Console.WriteLine("MIDI IN MORE DATA");
// A = Packed MIDI message, B = Time in milliseconds since Start
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_ERROR:
// A = Invalid MIDI message, B = Time in milliseconds since Start
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_LONG_ERROR:
// A = Pointer to MIDI header, B = Time in milliseconds since Start
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_OPEN:
this.IsOpen = true;
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_CLOSE:
this.IsOpen = false;
break;
}
}
/// <summary>
/// Callback function to be called by the system.
/// </summary>
/// <param name="handle">An <see cref="API.MidiDeviceHandle"/> to the MIDI output device to associate with the callback function.</param>
/// <param name="message">An <see cref="API.MidiOutputMessage"/> containing the message.</param>
/// <param name="instance">An <see cref="IntPtr"/> to the instance data supplied by the <see cref="API.OpenMidiOutputDevice"/> function.</param>
/// <param name="messageParameterA">An <see cref="IntPtr"/> to the first message parameter.</param>
/// <param name="messageParameterB">An <see cref="IntPtr"/> to the second message parameter.</param>
private void Callback(API.MidiDeviceHandle handle, API.MidiOutputMessage message, IntPtr instance, IntPtr messageParameterA, IntPtr messageParameterB)
{
if (message == API.MidiOutputMessage.MIDI_OUTPUT_MESSAGE_OPEN)
{
this.IsOpen = true;
}
else if (message == API.MidiOutputMessage.MIDI_OUTPUT_MESSAGE_CLOSE)
{
this.IsOpen = false;
}
else
{
// API.MidiOutputMessage.MIDI_OUTPUT_MESSAGE_DONE
Ready?.Invoke(this, new EventArgs());
}
}
