void Tick()
{
DateTime tickTime = DateTime.Now;
if (toRelease != null && tickTime >= startTime + TimeSpan.FromMilliseconds(toRelease.MillisecondsElapsed))
{
channel.Note = null;
toRelease = null;
}
if (noMoreNotes && toRelease == null)
{
Stop();
return;
}
else if (noMoreNotes)
{
return;
}
while (tickTime >= startTime + TimeSpan.FromMilliseconds(millisecondsFromStart))
{
MidiToken midiToken = null;
int note = 0;
while (midiToken == null ||
(midiToken.TokenType != MidiTokenType.Note &&
midiToken.TokenType != MidiTokenType.Rest))
{
midiToken = DecodeNextToken(tune, ref index, out tokenIndex);
switch (midiToken.TokenType)
{
case MidiTokenType.Null:
noMoreNotes = true;
return;
case MidiTokenType.Octave:
currentOctave = midiToken.Code.ToString()[0];
break;
case MidiTokenType.Tempo:
tempo = midiToken.Code;
break;
case MidiTokenType.Instrument:
channel.Instrument = (SpeccyMIDIInstrument)midiToken.Code;
break;
case MidiTokenType.Volume:
volume = midiToken.Code;
break;
case MidiTokenType.Rest:
note = -1;
break;
case MidiTokenType.Note:
note = midiToken.Code;
break;
case MidiTokenType.Duration:
duration = midiToken.Value;
break;
default:
throw new MidiParsingException(tokenIndex, "Expecting Tempo, Instrument, Volume, Note, Note Group, or Rest");
}
}
if (note != -1)
{
if (toRelease != null)
{
channel.Note = null;
}
channel.SetNote((SpeccyMIDINotes)note, volume);
toRelease = new ReleaseInfo(note, millisecondsFromStart + 240000.0 * duration / tempo);
}
millisecondsFromStart += 240000.0 * duration / tempo;
}
}
MidiToken NewToken(List<MidiToken> tokens, int time, byte type)
{
var token = new MidiToken { Time = time, Type = type, OriginalIndex = tokens.Count };
tokens.Add(token);
return token;
}
