Handle edits while playing precisely.

This avoids stuck notes if active notes are edited, but without stopping all
active notes in the region on any edit as before.

This implementation injects note ons in places that aren't actually note
starts.  Depending on how percussive the instrument is, this may not be
desired.  In the future, an option for this would be an improvement, but there
are other places where "start notes in the middle" is a reasonable option.  I
think that should be handled universally if we're to do it at all, so not
considering it a part of this fix for now.

1 files changed, 52 insertions, 49 deletions

diff --git a/libs/ardour/midi_playlist.cc b/libs/ardour/midi_playlist.cc
index 60753d0baa..398234e2ba 100644
--- a/libs/ardour/midi_playlist.cc
+++ b/libs/ardour/midi_playlist.cc
@@ -17,21 +17,22 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 
-#include <cassert>
-
 #include <algorithm>
+#include <cassert>
+#include <cstdlib>
 #include <iostream>
 #include <utility>
 
-#include <stdlib.h>
-
 #include "evoral/EventList.hpp"
 
+#include "ardour/beats_frames_converter.h"
 #include "ardour/debug.h"
 #include "ardour/midi_model.h"
 #include "ardour/midi_playlist.h"
 #include "ardour/midi_region.h"
+#include "ardour/midi_source.h"
 #include "ardour/midi_state_tracker.h"
+#include "ardour/session.h"
 #include "ardour/types.h"
 
 #include "i18n.h"
@@ -43,6 +44,7 @@ using namespace std;
 MidiPlaylist::MidiPlaylist (Session& session, const XMLNode& node, bool hidden)
 	: Playlist (session, node, DataType::MIDI, hidden)
 	, _note_mode(Sustained)
+	, _read_end(0)
 {
 #ifndef NDEBUG
 	const XMLProperty* prop = node.property("type");
@@ -61,12 +63,14 @@ MidiPlaylist::MidiPlaylist (Session& session, const XMLNode& node, bool hidden)
 MidiPlaylist::MidiPlaylist (Session& session, string name, bool hidden)
 	: Playlist (session, name, DataType::MIDI, hidden)
 	, _note_mode(Sustained)
+	, _read_end(0)
 {
 }
 
 MidiPlaylist::MidiPlaylist (boost::shared_ptr<const MidiPlaylist> other, string name, bool hidden)
 	: Playlist (other, name, hidden)
 	, _note_mode(other->_note_mode)
+	, _read_end(0)
 {
 }
 
@@ -77,6 +81,7 @@ MidiPlaylist::MidiPlaylist (boost::shared_ptr<const MidiPlaylist> other,
                             bool                                  hidden)
 	: Playlist (other, start, dur, name, hidden)
 	, _note_mode(other->_note_mode)
+	, _read_end(0)
 {
 }
 
@@ -103,13 +108,18 @@ struct EventsSortByTimeAndType {
 framecnt_t
 MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framecnt_t dur, unsigned chan_n)
 {
+	typedef pair<MidiStateTracker*,framepos_t> TrackerInfo;
+
 	Playlist::RegionReadLock rl (this);
 
 	DEBUG_TRACE (DEBUG::MidiPlaylistIO,
 	             string_compose ("---- MidiPlaylist::read %1 .. %2 (%3 trackers) ----\n",
 	                             start, start + dur, _note_trackers.size()));
 
-	typedef pair<MidiStateTracker*,framepos_t> TrackerInfo;
+	/* First, emit any queued edit fixup events at start. */
+	for (NoteTrackers::iterator t = _note_trackers.begin(); t != _note_trackers.end(); ++t) {
+		t->second->fixer.emit(dst, _read_end, t->second->tracker);
+	}
 
 	/* Find relevant regions that overlap [start..end] */
 	const framepos_t                         end = start + dur - 1;
@@ -158,11 +168,11 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 		}
 
 		/* Get the existing note tracker for this region, or create a new one. */
-		NoteTrackers::iterator t           = _note_trackers.find (mr.get());
-		MidiStateTracker*      tracker     = NULL;
-		bool                   new_tracker = false;
+		NoteTrackers::iterator           t           = _note_trackers.find (mr.get());
+		bool                             new_tracker = false;
+		boost::shared_ptr<RegionTracker> tracker;
 		if (t == _note_trackers.end()) {
-			tracker = new MidiStateTracker;
+			tracker     = boost::shared_ptr<RegionTracker>(new RegionTracker);
 			new_tracker = true;
 			DEBUG_TRACE (DEBUG::MidiPlaylistIO,
 			             string_compose ("\tPre-read %1 (%2 .. %3): new tracker\n",
@@ -171,13 +181,13 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 			tracker = t->second;
 			DEBUG_TRACE (DEBUG::MidiPlaylistIO,
 			             string_compose ("\tPre-read %1 (%2 .. %3): %4 active notes\n",
-			                             mr->name(), mr->position(), mr->last_frame(), tracker->on()));
+			                             mr->name(), mr->position(), mr->last_frame(), tracker->tracker.on()));
 		}
 
-		/** Read from region into target. */
-		mr->read_at (tgt, start, dur, chan_n, _note_mode, tracker);
+		/* Read from region into target. */
+		mr->read_at (tgt, start, dur, chan_n, _note_mode, &tracker->tracker);
 		DEBUG_TRACE (DEBUG::MidiPlaylistIO,
-		             string_compose ("\tPost-read: %1 active notes\n", tracker->on()));
+		             string_compose ("\tPost-read: %1 active notes\n", tracker->tracker.on()));
 
 		if (find (ended.begin(), ended.end(), *i) != ended.end()) {
 			/* Region ended within the read range, so resolve any active notes
@@ -187,8 +197,7 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 			             string_compose ("\t%1 ended, resolve notes and delete (%2) tracker\n",
 			                             mr->name(), ((new_tracker) ? "new" : "old")));
 
-			tracker->resolve_notes (tgt, (*i)->last_frame());
-			delete tracker;
+			tracker->tracker.resolve_notes (tgt, (*i)->last_frame());
 			if (!new_tracker) {
 				_note_trackers.erase (t);
 			}
@@ -216,17 +225,40 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 	}
 
 	DEBUG_TRACE (DEBUG::MidiPlaylistIO, "---- End MidiPlaylist::read ----\n");
+	_read_end = start + dur;
 	return dur;
 }
 
 void
+MidiPlaylist::region_edited(boost::shared_ptr<Region>         region,
+                            const MidiModel::NoteDiffCommand* cmd)
+{
+	typedef MidiModel::NoteDiffCommand Command;
+
+	boost::shared_ptr<MidiRegion> mr = boost::dynamic_pointer_cast<MidiRegion>(region);
+	if (!mr || !_session.transport_rolling()) {
+		return;
+	}
+
+	/* Take write lock to prevent concurrency with read(). */
+	Playlist::RegionWriteLock lock(this);
+
+	NoteTrackers::iterator t = _note_trackers.find(mr.get());
+	if (t == _note_trackers.end()) {
+		return; /* Region is not currently active, nothing to do. */
+	}
+
+	/* Queue any necessary edit compensation events. */
+	t->second->fixer.prepare(
+		_session.tempo_map(), cmd, mr->position() - mr->start(),
+		_read_end, mr->midi_source()->model()->active_notes());
+}
+
+void
 MidiPlaylist::reset_note_trackers ()
 {
 	Playlist::RegionWriteLock rl (this, false);
 
-	for (NoteTrackers::iterator n = _note_trackers.begin(); n != _note_trackers.end(); ++n) {
-		delete n->second;
-	}
 	DEBUG_TRACE (DEBUG::MidiTrackers, string_compose ("%1 reset all note trackers\n", name()));
 	_note_trackers.clear ();
 }
@@ -237,8 +269,7 @@ MidiPlaylist::resolve_note_trackers (Evoral::EventSink<framepos_t>& dst, framepo
 	Playlist::RegionWriteLock rl (this, false);
 
 	for (NoteTrackers::iterator n = _note_trackers.begin(); n != _note_trackers.end(); ++n) {
-		n->second->resolve_notes(dst, time);
-		delete n->second;
+		n->second->tracker.resolve_notes(dst, time);
 	}
 	DEBUG_TRACE (DEBUG::MidiTrackers, string_compose ("%1 resolve all note trackers\n", name()));
 	_note_trackers.clear ();
@@ -248,14 +279,7 @@ void
 MidiPlaylist::remove_dependents (boost::shared_ptr<Region> region)
 {
 	/* MIDI regions have no dependents (crossfades) but we might be tracking notes */
-	NoteTrackers::iterator t = _note_trackers.find (region.get());
-
-	/* GACK! THREAD SAFETY! */
-
-	if (t != _note_trackers.end()) {
-		delete t->second;
-		_note_trackers.erase (t);
-	}
+	_note_trackers.erase(region.get());
 }
 
 int
@@ -355,24 +379,3 @@ MidiPlaylist::contained_automation()
 
 	return ret;
 }
-
-
-bool
-MidiPlaylist::region_changed (const PBD::PropertyChange& what_changed, boost::shared_ptr<Region> region)
-{
-	if (in_flush || in_set_state) {
-		return false;
-	}
-
-	PBD::PropertyChange our_interests;
-	our_interests.add (Properties::midi_data);
-
-	bool parent_wants_notify = Playlist::region_changed (what_changed, region);
-
-	if (parent_wants_notify || what_changed.contains (our_interests)) {
-		notify_contents_changed ();
-	}
-
-	return true;
-}
-