private string getChannelString(ChannelMessage channelMessage, MidiEvent midiEvent, ref StringBuilder lilyString)
{
string returnString = "";
if (channelMessage.Command == ChannelCommand.NoteOn)
{
if (channelMessage.Data2 > 0) // Data2 = loudness
{
// Append the new note.
lilyString.Append(MidiToLilyHelper.GetLilyNoteName(_previousMidiKey, channelMessage.Data1));
returnString += MidiToLilyHelper.GetLilyNoteName(_previousMidiKey, channelMessage.Data1);
_previousMidiKey = channelMessage.Data1;
_startedNoteIsClosed = false;
}
else if (!_startedNoteIsClosed)
{
// Finish the previous note with the length.
double percentageOfBar;
string noteLength = MidiToLilyHelper.GetLilypondNoteLength(_previousNoteAbsoluteTicks, midiEvent.AbsoluteTicks, _division, _beatNote, _beatsPerBar, out percentageOfBar);
lilyString.Append(noteLength);
_previousNoteAbsoluteTicks = midiEvent.AbsoluteTicks;
lilyString.Append(" ");
returnString += noteLength;
returnString += " ";
_percentageOfBarReached += percentageOfBar;
if (_percentageOfBarReached >= 1)
{
lilyString.AppendLine("|");
returnString += "|";
_percentageOfBarReached -= 1;
}
_startedNoteIsClosed = true;
}
else
{
returnString += "r";
lilyString.Append("r");
}
}
return(returnString);
}
private string getEndOfTrackString(MetaMessage metaMessage, MidiEvent midiEvent, ref StringBuilder lilyString)
{
string returnString = "";
if (_previousNoteAbsoluteTicks > 0)
{
// Finish the last notelength.
double percentageOfBar;
string noteLength = MidiToLilyHelper.GetLilypondNoteLength(_previousNoteAbsoluteTicks, midiEvent.AbsoluteTicks, _division, _beatNote, _beatsPerBar, out percentageOfBar);
returnString += noteLength;
returnString += " ";
lilyString.Append(noteLength);
lilyString.Append(" ");
_percentageOfBarReached += percentageOfBar;
if (_percentageOfBarReached >= 1)
{
returnString += "|";
lilyString.AppendLine("|");
percentageOfBar = percentageOfBar - 1;
}
}
return(returnString);
}
public string Load(string fileName)
{
Sequence sequence = new Sequence();
sequence.Load(fileName);
StringBuilder lilypondContent = new StringBuilder();
lilypondContent.AppendLine("\\relative c' {");
lilypondContent.AppendLine("\\clef treble");
int division = sequence.Division;
int previousMidiKey = 60; // Central C;
int previousNoteAbsoluteTicks = 0;
double percentageOfBarReached = 0;
bool startedNoteIsClosed = true;
for (int i = 0; i < sequence.Count(); i++)
{
Track track = sequence[i];
foreach (var midiEvent in track.Iterator())
{
IMidiMessage midiMessage = midiEvent.MidiMessage;
// TODO: Split this switch statements and create separate logic.
// We want to split this so that we can expand our functionality later with new keywords for example.
// Hint: Command pattern? Strategies? Factory method?
switch (midiMessage.MessageType)
{
case MessageType.Meta:
var metaMessage = midiMessage as MetaMessage;
switch (metaMessage.MetaType)
{
case MetaType.TimeSignature:
byte[] timeSignatureBytes = metaMessage.GetBytes();
_beatNote = timeSignatureBytes[0];
_beatsPerBar = (int)(1 / Math.Pow(timeSignatureBytes[1], -2));
lilypondContent.AppendLine($"\\time {_beatNote}/{_beatsPerBar}");
break;
case MetaType.Tempo:
byte[] tempoBytes = metaMessage.GetBytes();
int tempo = (tempoBytes[0] & 0xff) << 16 | (tempoBytes[1] & 0xff) << 8 | (tempoBytes[2] & 0xff);
_bpm = 60000000 / tempo;
lilypondContent.AppendLine($"\\tempo 4={_bpm}");
break;
case MetaType.EndOfTrack:
if (previousNoteAbsoluteTicks > 0)
{
// Finish the last notelength.
double percentageOfBar;
lilypondContent.Append(MidiToLilyHelper.GetLilypondNoteLength(previousNoteAbsoluteTicks, midiEvent.AbsoluteTicks, division, _beatNote, _beatsPerBar, out percentageOfBar));
lilypondContent.Append(" ");
percentageOfBarReached += percentageOfBar;
if (percentageOfBarReached >= 1)
{
lilypondContent.AppendLine("|");
percentageOfBar = percentageOfBar - 1;
}
}
break;
default: break;
}
break;
case MessageType.Channel:
var channelMessage = midiEvent.MidiMessage as ChannelMessage;
if (channelMessage.Command == ChannelCommand.NoteOn)
{
if (channelMessage.Data2 > 0) // Data2 = loudness
{
// Append the new note.
lilypondContent.Append(MidiToLilyHelper.GetLilyNoteName(previousMidiKey, channelMessage.Data1));
previousMidiKey = channelMessage.Data1;
startedNoteIsClosed = false;
}
else if (!startedNoteIsClosed)
{
// Finish the previous note with the length.
double percentageOfBar;
lilypondContent.Append(MidiToLilyHelper.GetLilypondNoteLength(previousNoteAbsoluteTicks, midiEvent.AbsoluteTicks, division, _beatNote, _beatsPerBar, out percentageOfBar));
previousNoteAbsoluteTicks = midiEvent.AbsoluteTicks;
lilypondContent.Append(" ");
percentageOfBarReached += percentageOfBar;
if (percentageOfBarReached >= 1)
{
lilypondContent.AppendLine("|");
percentageOfBarReached -= 1;
}
startedNoteIsClosed = true;
}
else
{
lilypondContent.Append("r");
}
}
break;
}
}
}
lilypondContent.Append("}");
return(lilypondContent.ToString());
}
