lollis: make a single drag be represented by a single Command object (for undo/redo)

gtk2_ardour/midi_region_view.cc

@@ -3384,15 +3384,62 @@ MidiRegionView::change_note_length (NoteBase* event, Temporal::Beats t)
 {
 	note_diff_add_change (event, MidiModel::NoteDiffCommand::Length, t);
 }
+
 void
+MidiRegionView::begin_drag_edit (std::string const & why)
+{
+	start_note_diff_command (why);
+}
+
+void
+MidiRegionView::drag_apply ()
+{
+	if (!_note_diff_command) {
+		return;
+	}
+
+	bool add_or_remove = _note_diff_command->adds_or_removes();
+
+	if (add_or_remove) {
+		// Mark all selected notes for selection when model reloads
+		for (auto const & sel : _selection) {
+			_marked_for_selection.insert (sel->note());
+		}
+	}
+
+	{
+		PBD::Unwinder<bool> puw (_select_all_notes_after_add, true);
+		/*note that we don't use as_commit here, because that would BEGIN a new undo record; we already have one underway*/
+		_model->apply_diff_command_as_subcommand (*trackview.session(), _note_diff_command);
+	}
+}
+
+void
+MidiRegionView::mid_drag_edit ()
+{
+	drag_apply ();
+	_note_diff_command = _model->new_note_diff_command ();
+}
+
+void
+MidiRegionView::end_drag_edit (bool apply)
+{
+	if (apply) {
+		drag_apply ();
+		trackview.editor().commit_reversible_command ();
+		_note_diff_command = nullptr;
+	} else {
+		abort_note_diff ();
+	}
+}
+
+bool
 MidiRegionView::set_velocity_for_notes (std::vector<NoteBase*> notes, int velocity)
 {
 	/* Does not use selection, used when drawing/dragging in velocity lane */
 
 	bool changed = false;
 
-	start_note_diff_command (_("set velocities"));
-
 	for (auto & note : notes) {
 
 		int delta = velocity - note->note()->velocity();
@@ -3405,11 +3452,7 @@ MidiRegionView::set_velocity_for_notes (std::vector<NoteBase*> notes, int veloci
 		change_note_velocity (note, delta, true);
 	}
 
-	if (changed) {
-		apply_note_diff ();
-	} else {
-		abort_note_diff ();
-	}
+	return changed;
 }
 
 void

gtk2_ardour/midi_region_view.h

@@ -180,6 +180,10 @@ public:
 	void end_write();
 	void extend_active_notes();
 
+	void begin_drag_edit (std::string const & why);
+	void mid_drag_edit ();
+	void end_drag_edit (bool apply);
+
 	void display_model(std::shared_ptr<ARDOUR::MidiModel> model);
 
 	/* note_diff commands should start here; this initiates an undo record */
@@ -288,7 +292,7 @@ public:
 	void change_note_lengths (bool, bool, Temporal::Beats beats, bool start, bool end);
 	void change_velocities (bool up, bool fine, bool allow_smush, bool all_together);
 	void set_velocity (NoteBase* primary, int velocity);
-	void set_velocity_for_notes (std::vector<NoteBase*> notes, int velocity);
+	bool set_velocity_for_notes (std::vector<NoteBase*> notes, int velocity);
 	void transpose (bool up, bool fine, bool allow_smush);
 	void nudge_notes (bool forward, bool fine);
 	void channel_edit ();
@@ -583,6 +587,7 @@ public:
 	void model_changed ();
 
 	void sync_ghost_selection (NoteBase*);
+	void drag_apply ();
 };
 
 

gtk2_ardour/velocity_ghost_region.cc

@@ -55,6 +55,7 @@ VelocityGhostRegion::VelocityGhostRegion (MidiRegionView& mrv, TimeAxisView& tv,
 	, dragging (false)
 	, dragging_line (nullptr)
 	, last_drag_x (-1)
+	, drag_did_change (false)
 {
 	base_rect->Event.connect (sigc::mem_fun (*this, &VelocityGhostRegion::base_event));
 }
@@ -79,13 +80,14 @@ VelocityGhostRegion::base_event (GdkEvent* ev)
 			} else if (last_drag_x < ev->motion.x) {
 				/* rightward, "later" motion */
 				lollis_between (last_drag_x, ev->motion.x, affected_lollis);
-			} else {
+ 			} else {
 				/* leftward, "earlier" motion */
 				lollis_between (ev->motion.x, last_drag_x, affected_lollis);
 			}
 			if (!affected_lollis.empty()) {
 				int velocity = y_position_to_velocity (r.height() - (r.y1 - ev->motion.y));
-				mrv->set_velocity_for_notes (affected_lollis, velocity);
+				drag_did_change |= mrv->set_velocity_for_notes (affected_lollis, velocity);
+				mrv->mid_drag_edit ();
 			}
 			if (dragging) {
 				dragging_line->add_point (ArdourCanvas::Duple (ev->motion.x - r.x0, ev->motion.y - r.y0));
@@ -97,6 +99,7 @@ VelocityGhostRegion::base_event (GdkEvent* ev)
 		if (ev->button.button == 1) {
 			desensitize_lollis ();
 			dragging = true;
+			drag_did_change = false;
 			last_drag_x = -1;
 			if (!dragging_line) {
 				dragging_line = new ArdourCanvas::PolyLine (_note_group);
@@ -107,10 +110,12 @@ VelocityGhostRegion::base_event (GdkEvent* ev)
 			dragging_line->show();
 			dragging_line->raise_to_top();
 			base_rect->grab();
+			mrv->begin_drag_edit (_("draw velocities"));
 		}
 		break;
 	case GDK_BUTTON_RELEASE:
 		if (ev->button.button == 1) {
+			mrv->end_drag_edit (drag_did_change);
 			base_rect->ungrab();
 			dragging_line->hide ();
 			dragging = false;

gtk2_ardour/velocity_ghost_region.h

@@ -51,6 +51,7 @@ private:
 	bool dragging;
 	ArdourCanvas::PolyLine* dragging_line;
 	int last_drag_x;
+	bool drag_did_change;
 
 	bool base_event (GdkEvent*);
 	bool lollevent (GdkEvent*, MidiGhostRegion::GhostEvent*);