MidiSheetMusic.MidiFile.CombineToSingleTrack C# (CSharp) Method

        public static MidiTrack CombineToSingleTrack(List<MidiTrack> tracks)
        {
            /* Add all notes into one track */
            MidiTrack result = new MidiTrack(1);

            if (tracks.Count == 0) {
            return result;
            }
            else if (tracks.Count == 1) {
            MidiTrack track = tracks[0];
            foreach (MidiNote note in track.Notes) {
                result.AddNote(note);
            }
            return result;
            }

            int[] noteindex = new int[64];
            int[] notecount = new int[64];

            for (int tracknum = 0; tracknum < tracks.Count; tracknum++) {
            noteindex[tracknum] = 0;
            notecount[tracknum] = tracks[tracknum].Notes.Count;
            }
            MidiNote prevnote = null;
            while (true) {
            MidiNote lowestnote = null;
            int lowestTrack = -1;
            for (int tracknum = 0; tracknum < tracks.Count; tracknum++) {
                MidiTrack track = tracks[tracknum];
                if (noteindex[tracknum] >= notecount[tracknum]) {
                    continue;
                }
                MidiNote note = track.Notes[ noteindex[tracknum] ];
                if (lowestnote == null) {
                    lowestnote = note;
                    lowestTrack = tracknum;
                }
                else if (note.StartTime < lowestnote.StartTime) {
                    lowestnote = note;
                    lowestTrack = tracknum;
                }
                else if (note.StartTime == lowestnote.StartTime && note.Number < lowestnote.Number) {
                    lowestnote = note;
                    lowestTrack = tracknum;
                }
            }
            if (lowestnote == null) {
                /* We've finished the merge */
                break;
            }
            noteindex[lowestTrack]++;
            if ((prevnote != null) && (prevnote.StartTime == lowestnote.StartTime) &&
                (prevnote.Number == lowestnote.Number) ) {

                /* Don't add duplicate notes, with the same start time and number */
                if (lowestnote.Duration > prevnote.Duration) {
                    prevnote.Duration = lowestnote.Duration;
                }
            }
            else {
                result.AddNote(lowestnote);
                prevnote = lowestnote;
            }
            }

            return result;
        }