public static IEnumerable <MIDIEvent> MergeWithBuffer(IEnumerable <MIDIEvent> sequence, FastList <MIDIEvent> buffer)
{
double bdeltasub = 0;
foreach (var _e in sequence)
{
var e = _e.Clone();
while (!buffer.ZeroLen && buffer.First.DeltaTime - bdeltasub < e.DeltaTime)
{
var be = buffer.Pop().Clone();
be.DeltaTime -= bdeltasub;
bdeltasub = 0;
e.DeltaTime -= be.DeltaTime;
yield return(be);
}
yield return(e);
bdeltasub += e.DeltaTime;
}
while (!buffer.ZeroLen)
{
var be = buffer.Pop().Clone();
be.DeltaTime -= bdeltasub;
bdeltasub = 0;
yield return(be);
}
}
public static IEnumerable <Note> ExtractNotes(IEnumerable <MIDIEvent> sequence, FastList <MIDIEvent> otherEvents = null)
{
double time = 0;
FastList <DecodedNote>[] unendedNotes = new FastList <DecodedNote> [256 * 16];
FastList <DecodedNote> notesQueue = new FastList <DecodedNote>();
for (int i = 0; i < unendedNotes.Length; i++)
{
unendedNotes[i] = new FastList <DecodedNote>();
}
double delta = 0;
foreach (var e in sequence)
{
time += e.DeltaTime;
if (e is NoteOnEvent)
{
var n = e as NoteOnEvent;
var note = new DecodedNote()
{
note = new Note(n.Channel, n.Key, n.Velocity, time, double.PositiveInfinity)
};
unendedNotes[n.Key * 16 + n.Channel].Add(note);
notesQueue.Add(note);
delta += e.DeltaTime;
}
else if (e is NoteOffEvent)
{
var n = e as NoteOffEvent;
var arr = unendedNotes[n.Key * 16 + n.Channel];
if (arr.ZeroLen)
{
continue;
}
var note = arr.Pop();
note.ended = true;
note.note.End = time;
delta += e.DeltaTime;
}
else
{
if (otherEvents != null)
{
var ev = e.Clone();
ev.DeltaTime += delta;
delta = 0;
otherEvents.Add(ev);
}
}
if (notesQueue.First != null && notesQueue.First.ended)
{
yield return(notesQueue.Pop().note);
}
}
foreach (DecodedNote un in notesQueue)
{
if (!un.ended)
{
un.note.End = time;
}
yield return(un.note);
}
notesQueue.Unlink();
foreach (var s in unendedNotes)
{
s.Unlink();
}
}
