List <byte> process_track(byte[] data, uint songtrackdata_pointer, InstrumentMap instrument_map)
{
List <byte> ret = new List <byte>();
//Transform the data.
uint position = songtrackdata_pointer;
uint percussion = 0;
while (true)
{
uint b = U.u8(data, position);
position++;
ret.Add((byte)b);
if (b == 0xB1)
{
break;
}
else if (b == 0xB2 || b == 0xB3)
{
//repointer
U.append_u32(ret, U.p32(data, position) - songtrackdata_pointer);
position += 4;
}
else if (b == 0xBD)
{
uint next_byte = U.u8(data, position);
position++;
uint translated = instrument_map.translate(next_byte);
if (translated == 0)
{
percussion = next_byte;
}
ret.Add((byte)translated);
}
else if (b == 0xBB || b == 0xBC || b == 0xBE || b == 0xBF || b == 0xC0 || b == 0xC1 || b == 0xC2 || b == 0xC3 || b == 0xC4 || b == 0xC5 || b == 0xC8)
{
// These commands take a data byte that must not be processed.
ret.Add((byte)U.u8(data, position));
position++;
}
else if (b == 0xb9)
{//MEMACC 4バイト命令
//最初の1バイトはコピー済みなので、残りの3バイトコピーする.
ret.Add((byte)U.u8(data, position));
position++;
ret.Add((byte)U.u8(data, position));
position++;
ret.Add((byte)U.u8(data, position));
position++;
}
else if (percussion != 0 && b < 0x80)
{
uint inst = instrument_map.translate_percussion(percussion, b);
ret[ret.Count - 1] = ((byte)inst);
//There might be a volume marker, and then a 'gate' byte
//For now, assuming that any subsequent low-value bytes are extra data
//that should be passed as-is - even though previous experimentation suggested
//that these bytes could be used to specify a chord...
while (U.u8(data, position) < 0x80)
{// Volume marker
ret.Add((byte)U.u8(data, position));
position++;
}
}
}
return(ret);
}
