Fix mute of MIDI tracks with channel forcing.

This moves MIDI channel filtering into a reusable class and moves filtering to
the source, rather than modifying the buffer afterwards.  This is necessary so
that the playlist trackers reflect the emitted notes (and thus are able to stop
them in situations like mute).

As a perk, this is also faster because events are just dropped on read, rather
than pushed into a buffer then later removed (which is very slow).

Really hammering on mute or solo still seems to produce stuck notes
occasionally (perhaps related to multiple-on warnings).  I am not yet sure why,
but occasional beats always.

1 files changed, 12 insertions, 35 deletions

diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index f6ba10342a..e8b23b3431 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -403,17 +403,10 @@ MidiDiskstream::process (BufferSet& bufs, framepos_t transport_frame, pframes_t
 	}
 
 	if (nominally_recording || rec_nframes) {
-
-		// Pump entire port buffer into the ring buffer (FIXME: split cycles?)
-		MidiBuffer& buf = sp->get_midi_buffer(nframes);
-		ChannelMode mode = AllChannels;
-		uint32_t mask = 0xffff;
-
-		MidiTrack * mt = dynamic_cast<MidiTrack*> (_track);
-		if (mt) {
-			mode = mt->get_capture_channel_mode ();
-			mask = mt->get_capture_channel_mask ();
-		}
+		// Pump entire port buffer into the ring buffer (TODO: split cycles?)
+		MidiBuffer&        buf    = sp->get_midi_buffer(nframes);
+		MidiTrack*         mt     = dynamic_cast<MidiTrack*>(_track);
+		MidiChannelFilter* filter = mt ? &mt->capture_filter() : NULL;
 
 		for (MidiBuffer::iterator i = buf.begin(); i != buf.end(); ++i) {
 			Evoral::MIDIEvent<MidiBuffer::TimeType> ev(*i, false);
@@ -447,31 +440,12 @@ MidiDiskstream::process (BufferSet& bufs, framepos_t transport_frame, pframes_t
 			const framecnt_t loop_offset = _num_captured_loops * loop_length;
 			const framepos_t event_time = transport_frame + loop_offset - _accumulated_capture_offset + ev.time();
 			if (event_time < 0 || event_time < first_recordable_frame) {
+				/* Event out of range, skip */
 				continue;
 			}
-			switch (mode) {
-			case AllChannels:
-				_capture_buf->write(event_time,
-						    ev.type(), ev.size(), ev.buffer());
-				break;
-			case FilterChannels:
-				if (ev.is_channel_event()) {
-					if ((1<<ev.channel()) & mask) {
-						_capture_buf->write(event_time,
-								    ev.type(), ev.size(), ev.buffer());
-					}
-				} else {
-					_capture_buf->write(event_time,
-							    ev.type(), ev.size(), ev.buffer());
-				}
-				break;
-			case ForceChannel:
-				if (ev.is_channel_event()) {
-					ev.set_channel (PBD::ffs(mask) - 1);
-				}
-				_capture_buf->write(event_time,
-						    ev.type(), ev.size(), ev.buffer());
-				break;
+
+			if (!filter || !filter->filter(ev.buffer(), ev.size())) {
+				_capture_buf->write(event_time, ev.type(), ev.size(), ev.buffer());
 			}
 		}
 		g_atomic_int_add(const_cast<gint*>(&_frames_pending_write), nframes);
@@ -736,6 +710,9 @@ MidiDiskstream::read (framepos_t& start, framecnt_t dur, bool reversed)
 	framecnt_t loop_length = 0;
 	Location*  loc         = 0;
 
+	MidiTrack*         mt     = dynamic_cast<MidiTrack*>(_track);
+	MidiChannelFilter* filter = mt ? &mt->playback_filter() : NULL;
+
 	if (!reversed) {
 
 		loc = loop_location;
@@ -772,7 +749,7 @@ MidiDiskstream::read (framepos_t& start, framecnt_t dur, bool reversed)
 
 		this_read = min(dur,this_read);
 
-		if (midi_playlist()->read (*_playback_buf, start, this_read) != this_read) {
+		if (midi_playlist()->read (*_playback_buf, start, this_read, 0, filter) != this_read) {
 			error << string_compose(
 					_("MidiDiskstream %1: cannot read %2 from playlist at frame %3"),
 					id(), this_read, start) << endmsg;