/// <summary>
/// Sends events directly to the event queue without buffering
/// </summary>
/// <param name="events">The events to send</param>
/// <remarks>The total size of the events must be less than 64kb</remarks>
public void SendDirect(IEnumerable <MidiEvent> events)
{
if (null == events)
{
throw new ArgumentNullException("events");
}
if (IntPtr.Zero == _handle)
{
throw new InvalidOperationException("The stream is closed.");
}
if (IntPtr.Zero != _sendHeader.lpData)
{
throw new InvalidOperationException("The stream is busy playing.");
}
int baseEventSize = Marshal.SizeOf(typeof(MIDIEVENT));
int blockSize = 0;
IntPtr eventPointer = _sendEventBuffer;
var ofs = 0;
var ptrOfs = 0;
var hasEvents = false;
foreach (var @event in events)
{
hasEvents = true;
if (0xF0 != (@event.Message.Status & 0xF0))
{
blockSize += baseEventSize;
if (_SendBufferSize <= blockSize)
{
throw new ArgumentException("There are too many events in the event buffer - maximum size must be 64k", "events");
}
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = MidiUtility.PackMessage(@event.Message);
Marshal.StructureToPtr(se, new IntPtr(ptrOfs + eventPointer.ToInt64()), false);
ptrOfs += baseEventSize;
ofs = 0;
}
else if (0xFF == @event.Message.Status)
{
var mm = @event.Message as MidiMessageMeta;
if (0x51 == mm.Data1) // tempo
{
blockSize += baseEventSize;
if (_SendBufferSize <= blockSize)
{
throw new ArgumentException("There are too many events in the event buffer - maximum size must be 64k", "events");
}
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = (mm.Data[0] << 16) | (mm.Data[1] << 8) | mm.Data[2] | (MEVT_TEMPO << 24);
Marshal.StructureToPtr(se, new IntPtr(ptrOfs + eventPointer.ToInt64()), false);
ptrOfs += baseEventSize;
ofs = 0;
// TODO: This signal is sent too early. It should really wait until after the
// MEVT_TEMPO message is processed by the driver, but i have no easy way to
// do that. All we can do is hope, here
Interlocked.Exchange(ref _tempoSyncMessagesSentCount, 0);
}
else if (0x2f == mm.Data1) // end track
{
blockSize += baseEventSize;
if (_SendBufferSize <= blockSize)
{
throw new ArgumentException("There are too many events in the event buffer - maximum size must be 64k", "events");
}
// add a NOP message to it just to pad our output in case we're looping
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = (MEVT_NOP << 24);
Marshal.StructureToPtr(se, new IntPtr(ptrOfs + eventPointer.ToInt64()), false);
ptrOfs += baseEventSize;
ofs = 0;
}
else
{
ofs = @event.Position;
}
}
else // sysex
{
var msx = @event.Message as MidiMessageSysex;
var dl = msx.Data.Length + 1;
if (0 != (dl % 4))
{
dl += 4 - (dl % 4);
}
blockSize += baseEventSize + dl;
if (_SendBufferSize <= blockSize)
{
throw new ArgumentException("There are too many events in the event buffer - maximum size must be 64k", "events");
}
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = MEVT_F_LONG | (msx.Data.Length + 1);
Marshal.StructureToPtr(se, new IntPtr(ptrOfs + eventPointer.ToInt64()), false);
ptrOfs += baseEventSize;
Marshal.WriteByte(new IntPtr(ptrOfs + eventPointer.ToInt64()), msx.Status);
Marshal.Copy(msx.Data, 0, new IntPtr(ptrOfs + eventPointer.ToInt64() + 1), msx.Data.Length);
ptrOfs += dl;
ofs = 0;
}
}
if (hasEvents)
{
_sendHeader = default(MIDIHDR);
Interlocked.Exchange(ref _sendHeader.lpData, eventPointer);
_sendHeader.dwBufferLength = _sendHeader.dwBytesRecorded = unchecked ((uint)blockSize);
_sendEventBuffer = eventPointer;
int headerSize = Marshal.SizeOf(typeof(MIDIHDR));
_CheckOutResult(midiOutPrepareHeader(_handle, ref _sendHeader, headerSize));
_CheckOutResult(midiStreamOut(_handle, ref _sendHeader, headerSize));
}
}
void _SendBlock()
{
if (null == _sendQueue)
{
return;
}
if (IntPtr.Zero == _handle)
{
throw new InvalidOperationException("The stream is closed.");
}
if (IntPtr.Zero != Interlocked.CompareExchange(ref _sendHeader.lpData, _sendEventBuffer, IntPtr.Zero))
{
throw new InvalidOperationException("The stream is busy playing.");
}
int baseEventSize = Marshal.SizeOf(typeof(MIDIEVENT));
int blockSize = 0;
IntPtr eventPointer = _sendEventBuffer;
var ofs = 0;
var ptrOfs = 0;
for (; _sendQueuePosition < _sendQueue.Count; Interlocked.Exchange(ref _sendQueuePosition, _sendQueuePosition + 1))
{
var @event = _sendQueue[_sendQueuePosition];
if (0x00 != @event.Message.Status && 0xF0 != (@event.Message.Status & 0xF0))
{
if (_SendBufferSize < blockSize + baseEventSize)
{
break;
}
blockSize += baseEventSize;
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = MidiUtility.PackMessage(@event.Message);
var gch = GCHandle.Alloc(se, GCHandleType.Pinned);
CopyMemory(new IntPtr(ptrOfs + eventPointer.ToInt64()), gch.AddrOfPinnedObject(), Marshal.SizeOf(typeof(MIDIEVENT)));
gch.Free();
ptrOfs += baseEventSize;
ofs = 0;
}
else if (0xFF == @event.Message.Status)
{
var mm = @event.Message as MidiMessageMeta;
if (0x51 == mm.Data1) // tempo
{
if (_SendBufferSize < blockSize + baseEventSize)
{
break;
}
blockSize += baseEventSize;
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = (mm.Data[0] << 16) | (mm.Data[1] << 8) | mm.Data[2] | (MEVT_TEMPO << 24);
var gch = GCHandle.Alloc(se, GCHandleType.Pinned);
CopyMemory(new IntPtr(ptrOfs + eventPointer.ToInt64()), gch.AddrOfPinnedObject(), Marshal.SizeOf(typeof(MIDIEVENT)));
gch.Free();
ptrOfs += baseEventSize;
ofs = 0;
}
else if (0x2f == mm.Data1) // end track
{
if (_SendBufferSize < blockSize + baseEventSize)
{
break;
}
blockSize += baseEventSize;
// add a NOP message to it just to pad our output in case we're looping
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = (MEVT_NOP << 24);
var gch = GCHandle.Alloc(se, GCHandleType.Pinned);
CopyMemory(new IntPtr(ptrOfs + eventPointer.ToInt64()), gch.AddrOfPinnedObject(), Marshal.SizeOf(typeof(MIDIEVENT)));
gch.Free();
ptrOfs += baseEventSize;
ofs = 0;
}
else
{
ofs = @event.Position;
}
}
else // sysex or sysex part
{
byte[] data;
if (0 == @event.Message.Status)
{
data = (@event.Message as MidiMessageSysexPart).Data;
}
else
{
data = MidiUtility.ToMessageBytes(@event.Message);
}
var dl = data.Length;
if (0 != (dl % 4))
{
dl += 4 - (dl % 4);
}
if (_SendBufferSize < blockSize + baseEventSize + dl)
{
break;
}
blockSize += baseEventSize + dl;
var se = new MIDIEVENT();
se.dwDeltaTime = @event.Position + ofs;
se.dwStreamId = 0;
se.dwEvent = MEVT_F_LONG | data.Length;
var gch = GCHandle.Alloc(se, GCHandleType.Pinned);
CopyMemory(new IntPtr(ptrOfs + eventPointer.ToInt64()), gch.AddrOfPinnedObject(), Marshal.SizeOf(typeof(MIDIEVENT)));
gch.Free();
ptrOfs += baseEventSize;
Marshal.Copy(data, 0, new IntPtr(ptrOfs + eventPointer.ToInt64()), data.Length);
ptrOfs += dl;
ofs = 0;
}
}
_sendHeader = default(MIDIHDR);
_sendHeader.dwBufferLength = _sendHeader.dwBytesRecorded = unchecked ((uint)blockSize);
_sendHeader.lpData = _sendEventBuffer;
int headerSize = Marshal.SizeOf(typeof(MIDIHDR));
_CheckOutResult(midiOutPrepareHeader(_handle, ref _sendHeader, headerSize));
_CheckOutResult(midiStreamOut(_handle, ref _sendHeader, headerSize));
}