Add editor selection state to session history via a SelectionMemento, which

combines selection related editor properties with the current editor selection.

The related editor properties are:
mouse mode,
zoom setting,
left frame of the canvas,
y origin of the canvas.

Selection state now includes region views (storing the underlying region id)
and time.

This patch also fixes a region mute undo bug.

gtk2_ardour/audio_region_view.cc

@@ -1237,7 +1237,7 @@ AudioRegionView::add_gain_point_event (ArdourCanvas::Item *item, GdkEvent *ev, b
 	   can represent automation data with it.
 	*/
 
-	trackview.session()->begin_reversible_command (_("add gain control point"));
+	trackview.editor().begin_reversible_command (_("add gain control point"));
 	XMLNode &before = audio_region()->envelope()->get_state();
 
 	if (!audio_region()->envelope_active()) {
@@ -1251,7 +1251,7 @@ AudioRegionView::add_gain_point_event (ArdourCanvas::Item *item, GdkEvent *ev, b
 
 	XMLNode &after = audio_region()->envelope()->get_state();
 	trackview.session()->add_command (new MementoCommand<AutomationList>(*audio_region()->envelope().get(), &before, &after));
-	trackview.session()->commit_reversible_command ();
+	trackview.editor().commit_reversible_command ();
 }
 
 void

gtk2_ardour/automation_line.cc

@@ -283,7 +283,7 @@ AutomationLine::modify_point_y (ControlPoint& cp, double y)
 
 	double const x = trackview.editor().sample_to_pixel_unrounded (_time_converter->to((*cp.model())->when) - _offset);
 
-	trackview.editor().session()->begin_reversible_command (_("automation event move"));
+	trackview.editor().begin_reversible_command (_("automation event move"));
 	trackview.editor().session()->add_command (
 		new MementoCommand<AutomationList> (memento_command_binder(), &get_state(), 0));
 
@@ -304,7 +304,7 @@ AutomationLine::modify_point_y (ControlPoint& cp, double y)
 	trackview.editor().session()->add_command (
 		new MementoCommand<AutomationList> (memento_command_binder(), 0, &alist->get_state()));
 
-	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().commit_reversible_command ();
 	trackview.editor().session()->set_dirty ();
 }
 
@@ -456,7 +456,7 @@ AutomationLine::string_to_fraction (string const & s) const
 void
 AutomationLine::start_drag_single (ControlPoint* cp, double x, float fraction)
 {
-	trackview.editor().session()->begin_reversible_command (_("automation event move"));
+	trackview.editor().begin_reversible_command (_("automation event move"));
 	trackview.editor().session()->add_command (
 		new MementoCommand<AutomationList> (memento_command_binder(), &get_state(), 0));
 
@@ -482,7 +482,7 @@ AutomationLine::start_drag_single (ControlPoint* cp, double x, float fraction)
 void
 AutomationLine::start_drag_line (uint32_t i1, uint32_t i2, float fraction)
 {
-	trackview.editor().session()->begin_reversible_command (_("automation range move"));
+	trackview.editor().begin_reversible_command (_("automation range move"));
 	trackview.editor().session()->add_command (
 		new MementoCommand<AutomationList> (memento_command_binder (), &get_state(), 0));
 
@@ -502,7 +502,7 @@ AutomationLine::start_drag_line (uint32_t i1, uint32_t i2, float fraction)
 void
 AutomationLine::start_drag_multiple (list<ControlPoint*> cp, float fraction, XMLNode* state)
 {
-	trackview.editor().session()->begin_reversible_command (_("automation range move"));
+	trackview.editor().begin_reversible_command (_("automation range move"));
 	trackview.editor().session()->add_command (
 		new MementoCommand<AutomationList> (memento_command_binder(), state, 0));
 
@@ -857,7 +857,7 @@ AutomationLine::is_first_point (ControlPoint& cp)
 void
 AutomationLine::remove_point (ControlPoint& cp)
 {
-	trackview.editor().session()->begin_reversible_command (_("remove control point"));
+	trackview.editor().begin_reversible_command (_("remove control point"));
 	XMLNode &before = alist->get_state();
 
 	alist->erase (cp.model());
@@ -865,7 +865,7 @@ AutomationLine::remove_point (ControlPoint& cp)
 	trackview.editor().session()->add_command(
 		new MementoCommand<AutomationList> (memento_command_binder (), &before, &alist->get_state()));
 
-	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().commit_reversible_command ();
 	trackview.editor().session()->set_dirty ();
 }
 

gtk2_ardour/automation_region_view.cc

@@ -182,15 +182,15 @@ AutomationRegionView::add_automation_event (GdkEvent *, framepos_t when, double
 	double when_d = when;
 	_line->view_to_model_coord (when_d, y);
 
-	view->session()->begin_reversible_command (_("add automation event"));
+	view->editor().begin_reversible_command (_("add automation event"));
 	XMLNode& before = _line->the_list()->get_state();
 
 	_line->the_list()->add (when_d, y, with_guard_points, false);
 
 	XMLNode& after = _line->the_list()->get_state();
 
-	view->session()->commit_reversible_command (
+	view->session()->add_command (new MementoCommand<ARDOUR::AutomationList> (_line->memento_command_binder(), &before, &after));
-		new MementoCommand<ARDOUR::AutomationList> (_line->memento_command_binder(), &before, &after));
+	view->editor().commit_reversible_command ();
 
 	view->session()->set_dirty ();
 }

gtk2_ardour/automation_time_axis.cc

@@ -434,7 +434,7 @@ AutomationTimeAxisView::clear_clicked ()
 {
 	assert (_line || _view);
 
-	_session->begin_reversible_command (_("clear automation"));
+	_editor.begin_reversible_command (_("clear automation"));
 
 	if (_line) {
 		_line->clear ();
@@ -442,7 +442,7 @@ AutomationTimeAxisView::clear_clicked ()
 		_view->clear ();
 	}
 
-	_session->commit_reversible_command ();
+	_editor.commit_reversible_command ();
 	_session->set_dirty ();
 }
 
@@ -627,13 +627,14 @@ AutomationTimeAxisView::add_automation_event (GdkEvent* event, framepos_t when,
 
 	_editor.snap_to_with_modifier (when, event);
 
-	_session->begin_reversible_command (_("add automation event"));
+	_editor.begin_reversible_command (_("add automation event"));
 	XMLNode& before = list->get_state();
 
 	list->add (when, y, with_guard_points);
 
 	XMLNode& after = list->get_state();
-	_session->commit_reversible_command (new MementoCommand<ARDOUR::AutomationList> (*list, &before, &after));
+	_session->add_command (new MementoCommand<ARDOUR::AutomationList> (*list, &before, &after));
+	_editor.commit_reversible_command ();
 	_session->set_dirty ();
 }
 

gtk2_ardour/crossfade_edit.cc

@@ -780,7 +780,7 @@ CrossfadeEditor::apply_preset (Preset *preset)
 void
 CrossfadeEditor::apply ()
 {
-	_session->begin_reversible_command (_("Edit crossfade"));
+	the_editor().begin_reversible_command (_("Edit crossfade"));
 
 	XMLNode& before = xfade->get_state ();
 
@@ -793,7 +793,7 @@ CrossfadeEditor::apply ()
 			)
 		);
 
-	_session->commit_reversible_command ();
+	the_editor().commit_reversible_command ();
 }
 
 void

gtk2_ardour/editor.cc

@@ -305,6 +305,8 @@ Editor::Editor ()
 	
 	selection = new Selection (this);
 	cut_buffer = new Selection (this);
+	_selection_memento = new SelectionMemento ();
+	before.clear();
 
 	clicked_regionview = 0;
 	clicked_axisview = 0;
@@ -1392,6 +1394,7 @@ Editor::set_session (Session *t)
 
 	/* register for undo history */
 	_session->register_with_memento_command_factory(id(), this);
+	_session->register_with_memento_command_factory(_selection_memento->id(), _selection_memento);
 
 	ActionManager::ui_manager->signal_pre_activate().connect (sigc::mem_fun (*this, &Editor::action_pre_activated));
 
@@ -3317,6 +3320,7 @@ void
 Editor::begin_reversible_command (string name)
 {
 	if (_session) {
+		before.push_back (&_selection_memento->get_state ());
 		_session->begin_reversible_command (name);
 	}
 }
@@ -3325,6 +3329,7 @@ void
 Editor::begin_reversible_command (GQuark q)
 {
 	if (_session) {
+		before.push_back (&_selection_memento->get_state ());
 		_session->begin_reversible_command (q);
 	}
 }
@@ -3333,6 +3338,14 @@ void
 Editor::commit_reversible_command ()
 {
 	if (_session) {
+		if (before.size() == 1) {
+			_session->add_command (new MementoCommand<SelectionMemento>(*(_selection_memento), before.front(), &_selection_memento->get_state ()));
+		}
+
+		if (!before.empty()) {
+			before.pop_back();
+		}
+
 		_session->commit_reversible_command ();
 	}
 }
@@ -4182,7 +4195,7 @@ Editor::copy_playlists (TimeAxisView* v)
 void
 Editor::clear_playlists (TimeAxisView* v)
 {
-	begin_reversible_command (_("clear playlists"));
+	begin_reversible_command (_("clear playlists"));	
 	vector<boost::shared_ptr<ARDOUR::Playlist> > playlists;
 	_session->playlists->get (playlists);
 	mapover_tracks (sigc::mem_fun (*this, &Editor::mapped_clear_playlist), v, ARDOUR::Properties::select.property_id);
@@ -4220,6 +4233,12 @@ Editor::on_key_release_event (GdkEventKey* ev)
 	// return key_press_focus_accelerator_handler (*this, ev);
 }
 
+double
+Editor::get_y_origin () const
+{
+	return vertical_adjustment.get_value ();
+}
+
 /** Queue up a change to the viewport x origin.
  *  @param frame New x origin.
  */
@@ -4629,8 +4648,7 @@ Editor::set_punch_range (framepos_t start, framepos_t end, string cmd)
 		_session->set_auto_punch_location (loc);
 		XMLNode &after = _session->locations()->get_state();
 		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	}
+	} else {
-	else {
 		XMLNode &before = tpl->get_state();
 		tpl->set_hidden (false, this);
 		tpl->set (start, end);
@@ -4807,6 +4825,35 @@ Editor::get_regions_from_selection_and_entered ()
 	return regions;
 }
 
+void
+Editor::get_regionviews_by_id (PBD::ID const & id, RegionSelection & regions) const
+{
+	for (TrackViewList::const_iterator i = track_views.begin(); i != track_views.end(); ++i) {
+		RouteTimeAxisView* tatv;
+		
+		if ((tatv = dynamic_cast<RouteTimeAxisView*> (*i)) != 0) {
+			boost::shared_ptr<Playlist> pl;
+			std::vector<boost::shared_ptr<Region> > results;
+			boost::shared_ptr<Track> tr;
+			
+			if ((tr = tatv->track()) == 0) {
+				/* bus */
+				continue;
+			}
+			
+			if ((pl = (tr->playlist())) != 0) {
+				boost::shared_ptr<Region> r = pl->region_by_id (id);
+				if (r) {
+					RegionView* marv = tatv->view()->find_view (r);
+					if (marv) {
+						regions.push_back (marv);
+					}
+				}
+			}
+		}
+	}
+}
+
 void
 Editor::get_regions_corresponding_to (boost::shared_ptr<Region> region, vector<RegionView*>& regions, bool src_comparison)
 {
@@ -4966,8 +5013,15 @@ Editor::located ()
 }
 
 void
-Editor::region_view_added (RegionView *)
+Editor::region_view_added (RegionView * rv)
 {
+	for (list<PBD::ID>::iterator pr = selection->regions.pending.begin (); pr != selection->regions.pending.end (); ++pr) {
+		if (rv->region ()->id () == (*pr)) {
+			selection->add (rv);
+			selection->regions.pending.erase (pr);
+			break;
+		}
+	}
 	_summary->set_background_dirty ();
 }
 

gtk2_ardour/editor.h

@@ -58,6 +58,7 @@
 #include "enums.h"
 #include "editor_items.h"
 #include "region_selection.h"
+#include "selection_memento.h"
 
 namespace Gtkmm2ext {
 	class TearOff;
@@ -149,7 +150,7 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	double visible_canvas_height () const {
 		return _visible_canvas_height;
 	}
-	double trackviews_height() const;
+	double trackviews_height () const;
 
 	void cycle_snap_mode ();
 	void next_snap_choice ();
@@ -372,6 +373,7 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	void update_tearoff_visibility();
 	void reattach_all_tearoffs ();
 
+	double get_y_origin () const;
 	void reset_x_origin (framepos_t);
 	void reset_x_origin_to_follow_playhead ();
 	void reset_y_origin (double);
@@ -405,6 +407,8 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 
         void get_regions_corresponding_to (boost::shared_ptr<ARDOUR::Region> region, std::vector<RegionView*>& regions, bool src_comparison);
 
+	void get_regionviews_by_id (PBD::ID const & id, RegionSelection & regions) const;
+
 	void center_screen (framepos_t);
 
 	TrackViewList axis_views_from_routes (boost::shared_ptr<ARDOUR::RouteList>) const;
@@ -1716,6 +1720,7 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 
 	Selection* selection;
 	Selection* cut_buffer;
+	SelectionMemento* _selection_memento;
 
 	void time_selection_changed ();
         void update_time_selection_display ();
@@ -1875,7 +1880,7 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 
 	void write_selection ();
 
-	XMLNode *before; /* used in *_reversible_command */
+	std::list<XMLNode *> before; /* used in *_reversible_command */
 
 	void update_title ();
 	void update_title_s (const std::string & snapshot_name);

gtk2_ardour/editor_drag.cc

@@ -840,6 +840,12 @@ RegionMoveDrag::motion (GdkEvent* event, bool first_move)
 {
 	if (_copy && first_move) {
 
+		if (_x_constrained) {
+			_editor->begin_reversible_command (Operations::fixed_time_region_copy);
+		} else {
+			_editor->begin_reversible_command (Operations::region_copy);
+		}
+
 		/* duplicate the regionview(s) and region(s) */
 
 		list<DraggingView> new_regionviews;
@@ -890,6 +896,14 @@ RegionMoveDrag::motion (GdkEvent* event, bool first_move)
 
 			swap_grab (new_regionviews.front().view->get_canvas_group (), 0, event ? event->motion.time : 0);
 		}
+
+	} else if (!_copy && first_move) {
+
+		if (_x_constrained) {
+			_editor->begin_reversible_command (_("fixed time region drag"));
+		} else {
+			_editor->begin_reversible_command (Operations::region_drag);
+		}
 	}
 
 	RegionMotionDrag::motion (event, first_move);
@@ -1020,12 +1034,6 @@ RegionMoveDrag::finished_copy (bool const changed_position, bool const /*changed
 		return;
 	}
 
-	if (_x_constrained) {
-		_editor->begin_reversible_command (Operations::fixed_time_region_copy);
-	} else {
-		_editor->begin_reversible_command (Operations::region_copy);
-	}
-
 	/* insert the regions into their new playlists */
 	for (list<DraggingView>::const_iterator i = _views.begin(); i != _views.end();) {
 
@@ -1102,12 +1110,6 @@ RegionMoveDrag::finished_no_copy (
 		return;
 	}
 
-	if (_x_constrained) {
-		_editor->begin_reversible_command (_("fixed time region drag"));
-	} else {
-		_editor->begin_reversible_command (Operations::region_drag);
-	}
-
 	for (list<DraggingView>::const_iterator i = _views.begin(); i != _views.end(); ) {
 
 		RegionView* rv = i->view;
@@ -3632,7 +3634,7 @@ ControlPointDrag::finished (GdkEvent* event, bool movement_occurred)
 	}
 
 	_point->line().end_drag (_pushing, _final_index);
-	_editor->session()->commit_reversible_command ();
+	_editor->commit_reversible_command ();
 }
 
 void
@@ -3746,7 +3748,7 @@ LineDrag::finished (GdkEvent* event, bool movement_occured)
 		}
 	}
 
-	_editor->session()->commit_reversible_command ();
+	_editor->commit_reversible_command ();
 }
 
 void
@@ -5043,7 +5045,7 @@ AutomationRangeDrag::finished (GdkEvent* event, bool)
 		i->line->end_drag (false, 0);
 	}
 
-	_editor->session()->commit_reversible_command ();
+	_editor->commit_reversible_command ();
 }
 
 void
@@ -5189,9 +5191,11 @@ EditorRubberbandSelectDrag::select_things (int button_state, framepos_t x1, fram
 	}
 	
 	Selection::Operation op = ArdourKeyboard::selection_type (button_state);
-	
+
 	_editor->begin_reversible_command (_("rubberband selection"));
+
 	_editor->select_all_within (x1, x2 - 1, y1, y2, _editor->track_views, op, false);
+
 	_editor->commit_reversible_command ();
 }
 

gtk2_ardour/editor_locations.cc

@@ -28,7 +28,7 @@ using namespace Gtk;
 EditorLocations::EditorLocations (Editor* e)
 	: EditorComponent (e)
 {
-	_locations = new LocationUI;
+	_locations = new LocationUI ();
 	_scroller.set_policy (Gtk::POLICY_AUTOMATIC, Gtk::POLICY_NEVER);
 	_scroller.add (*_locations);
 }

gtk2_ardour/editor_markers.cc

@@ -654,12 +654,12 @@ Editor::mouse_add_new_marker (framepos_t where, bool is_cd, bool is_xrun)
 			return;
 		}
 		Location *location = new Location (*_session, where, where, markername, (Location::Flags) flags);
-		_session->begin_reversible_command (_("add marker"));
+		begin_reversible_command (_("add marker"));
+
 		XMLNode &before = _session->locations()->get_state();
 		_session->locations()->add (location, true);
 		XMLNode &after = _session->locations()->get_state();
 		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-		_session->commit_reversible_command ();
 
 		/* find the marker we just added */
 
@@ -668,6 +668,8 @@ Editor::mouse_add_new_marker (framepos_t where, bool is_cd, bool is_xrun)
 			/* make it the selected marker */
 			selection->set (lam->start);
 		}
+
+		commit_reversible_command ();
 	}
 }
 
@@ -721,12 +723,12 @@ Editor::remove_marker (ArdourCanvas::Item& item, GdkEvent*)
 gint
 Editor::really_remove_marker (Location* loc)
 {
-	_session->begin_reversible_command (_("remove marker"));
+	begin_reversible_command (_("remove marker"));
 	XMLNode &before = _session->locations()->get_state();
 	_session->locations()->remove (loc);
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 	return FALSE;
 }
 

gtk2_ardour/editor_mouse.cc

@@ -2344,8 +2344,6 @@ Editor::start_selection_grab (ArdourCanvas::Item* /*item*/, GdkEvent* event)
 	clicked_routeview->playlist()->add_region (region, selection->time[clicked_selection].start);
 	_session->add_command(new StatefulDiffCommand (playlist));
 
-	commit_reversible_command ();
-
 	c.disconnect ();
 
 	if (latest_regionviews.empty()) {
@@ -2356,8 +2354,11 @@ Editor::start_selection_grab (ArdourCanvas::Item* /*item*/, GdkEvent* event)
 	/* we need to deselect all other regionviews, and select this one
 	   i'm ignoring undo stuff, because the region creation will take care of it
 	*/
+
 	selection->set (latest_regionviews);
 
+	commit_reversible_command ();
+
 	_drags->set (new RegionMoveDrag (this, latest_regionviews.front()->get_canvas_group(), latest_regionviews.front(), latest_regionviews, false, false), event);
 }
 

gtk2_ardour/editor_ops.cc

@@ -219,14 +219,14 @@ Editor::split_regions_at (framepos_t where, RegionSelection& regions)
 		a = tmp;
 	}
 
+	latest_regionviews.clear ();
+
 	vector<sigc::connection> region_added_connections;
 
 	for (list<RouteTimeAxisView*>::iterator i = used_trackviews.begin(); i != used_trackviews.end(); ++i) {
 		region_added_connections.push_back ((*i)->view()->RegionViewAdded.connect (sigc::mem_fun(*this, &Editor::collect_new_region_view)));
 	}
 	
-	latest_regionviews.clear ();
-
 	while (used_playlists.size() > 0) {
 		list <boost::shared_ptr<Playlist > >::iterator i = used_playlists.begin();
 		(*i)->thaw();
@@ -236,8 +236,6 @@ Editor::split_regions_at (framepos_t where, RegionSelection& regions)
 	for (vector<sigc::connection>::iterator c = region_added_connections.begin(); c != region_added_connections.end(); ++c) {
 		(*c).disconnect ();
 	}
-	
-	commit_reversible_command ();
 
 	if (frozen){
 		EditorThaw(); /* Emit Signal */
@@ -251,7 +249,15 @@ Editor::split_regions_at (framepos_t where, RegionSelection& regions)
 			selection->add (latest_regionviews);  //these are the new regions created after the split
 		}
 		_ignore_follow_edits = false;
+	} else {
+		_ignore_follow_edits = true;
+		if( working_on_selection ) {
+			selection->add (latest_regionviews);  //these are the new regions created after the split
+		}
+		_ignore_follow_edits = false;
 	}
+
+	commit_reversible_command ();
 }
 
 /** Move one extreme of the current range selection.  If more than one range is selected,
@@ -1928,12 +1934,14 @@ Editor::add_location_from_selection ()
 	_session->locations()->next_available_name(rangename,"selection");
 	Location *location = new Location (*_session, start, end, rangename, Location::IsRangeMarker);
 
-	_session->begin_reversible_command (_("add marker"));
+	begin_reversible_command (_("add marker"));
+	
 	XMLNode &before = _session->locations()->get_state();
 	_session->locations()->add (location, true);
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	
+	commit_reversible_command ();
 }
 
 void
@@ -1948,12 +1956,14 @@ Editor::add_location_mark (framepos_t where)
 		return;
 	}
 	Location *location = new Location (*_session, where, where, markername, Location::IsMark);
-	_session->begin_reversible_command (_("add marker"));
+	begin_reversible_command (_("add marker"));
+	
 	XMLNode &before = _session->locations()->get_state();
 	_session->locations()->add (location, true);
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	
+	commit_reversible_command ();
 }
 
 void
@@ -1968,7 +1978,8 @@ Editor::remove_location_at_playhead_cursor ()
 	if (_session) {
 
 		//set up for undo
-		_session->begin_reversible_command (_("remove marker"));
+		begin_reversible_command (_("remove marker"));
+		
 		XMLNode &before = _session->locations()->get_state();
 		bool removed = false;
 
@@ -1986,7 +1997,8 @@ Editor::remove_location_at_playhead_cursor ()
 		if (removed) {
 			XMLNode &after = _session->locations()->get_state();
 			_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-			_session->commit_reversible_command ();
+			
+			commit_reversible_command ();
 		}
 	}
 }
@@ -2001,7 +2013,8 @@ Editor::add_locations_from_region ()
 		return;
 	}
 
-	_session->begin_reversible_command (selection->regions.size () > 1 ? _("add markers") : _("add marker"));
+	begin_reversible_command (selection->regions.size () > 1 ? _("add markers") : _("add marker"));
+	
 	XMLNode &before = _session->locations()->get_state();
 
 	for (RegionSelection::iterator i = rs.begin (); i != rs.end (); ++i) {
@@ -2015,7 +2028,8 @@ Editor::add_locations_from_region ()
 
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	
+	commit_reversible_command ();
 }
 
 /** Add a single range marker around all selected regions */
@@ -2028,7 +2042,8 @@ Editor::add_location_from_region ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("add marker"));
+	begin_reversible_command (_("add marker"));
+	
 	XMLNode &before = _session->locations()->get_state();
 
 	string markername;
@@ -2051,7 +2066,8 @@ Editor::add_location_from_region ()
 
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	
+	commit_reversible_command ();
 }
 
 /* MARKS */
@@ -2107,12 +2123,14 @@ void
 Editor::clear_markers ()
 {
 	if (_session) {
-		_session->begin_reversible_command (_("clear markers"));
+		begin_reversible_command (_("clear markers"));
+		
 		XMLNode &before = _session->locations()->get_state();
 		_session->locations()->clear_markers ();
 		XMLNode &after = _session->locations()->get_state();
 		_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-		_session->commit_reversible_command ();
+		
+		commit_reversible_command ();
 	}
 }
 
@@ -2120,27 +2138,30 @@ void
 Editor::clear_ranges ()
 {
 	if (_session) {
-		_session->begin_reversible_command (_("clear ranges"));
+		begin_reversible_command (_("clear ranges"));
+		
 		XMLNode &before = _session->locations()->get_state();
 
 		_session->locations()->clear_ranges ();
 
 		XMLNode &after = _session->locations()->get_state();
 		_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-		_session->commit_reversible_command ();
+		
+		commit_reversible_command ();
 	}
 }
 
 void
 Editor::clear_locations ()
 {
-	_session->begin_reversible_command (_("clear locations"));
+	begin_reversible_command (_("clear locations"));
+	
 	XMLNode &before = _session->locations()->get_state();
 	_session->locations()->clear ();
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	
-	_session->locations()->clear ();
+	commit_reversible_command ();
 }
 
 void
@@ -4537,11 +4558,11 @@ Editor::duplicate_some_regions (RegionSelection& regions, float times)
 		foo.insert (foo.end(), latest_regionviews.begin(), latest_regionviews.end());
 	}
 
-	commit_reversible_command ();
-
 	if (!foo.empty()) {
 		selection->set (foo);
 	}
+
+	commit_reversible_command ();
 }
 
 void
@@ -5168,8 +5189,8 @@ Editor::reset_region_gain_envelopes ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("reset region gain"));
+	begin_reversible_command (_("reset region gain"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
 		if (arv) {
@@ -5180,8 +5201,8 @@ Editor::reset_region_gain_envelopes ()
 			_session->add_command (new MementoCommand<AutomationList>(*arv->audio_region()->envelope().get(), &before, &alist->get_state()));
 		}
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -5221,8 +5242,8 @@ Editor::toggle_gain_envelope_active ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("region gain envelope active"));
+	begin_reversible_command (_("region gain envelope active"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
 		if (arv) {
@@ -5231,8 +5252,8 @@ Editor::toggle_gain_envelope_active ()
 			_session->add_command (new StatefulDiffCommand (arv->region()));
 		}
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -5248,15 +5269,15 @@ Editor::toggle_region_lock ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("toggle region lock"));
+	begin_reversible_command (_("toggle region lock"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		(*i)->region()->clear_changes ();
 		(*i)->region()->set_locked (!(*i)->region()->locked());
 		_session->add_command (new StatefulDiffCommand ((*i)->region()));
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -5272,15 +5293,15 @@ Editor::toggle_region_video_lock ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("Toggle Video Lock"));
+	begin_reversible_command (_("Toggle Video Lock"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		(*i)->region()->clear_changes ();
 		(*i)->region()->set_video_locked (!(*i)->region()->video_locked());
 		_session->add_command (new StatefulDiffCommand ((*i)->region()));
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -5296,16 +5317,16 @@ Editor::toggle_region_lock_style ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("region lock style"));
+	begin_reversible_command (_("region lock style"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		(*i)->region()->clear_changes ();
 		PositionLockStyle const ns = (*i)->region()->position_lock_style() == AudioTime ? MusicTime : AudioTime;
 		(*i)->region()->set_position_lock_style (ns);
 		_session->add_command (new StatefulDiffCommand ((*i)->region()));
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -5321,15 +5342,15 @@ Editor::toggle_opaque_region ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("change region opacity"));
+	begin_reversible_command (_("change region opacity"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		(*i)->region()->clear_changes ();
 		(*i)->region()->set_opaque (!(*i)->region()->opaque());
 		_session->add_command (new StatefulDiffCommand ((*i)->region()));
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -6137,8 +6158,8 @@ Editor::split_region_at_transients ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("split regions"));
+	begin_reversible_command (_("split regions"));
-
+	
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ) {
 
 		RegionSelection::iterator tmp;
@@ -6155,8 +6176,8 @@ Editor::split_region_at_transients ()
 
 		i = tmp;
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 
 }
 
@@ -6344,14 +6365,14 @@ Editor::place_transient()
 
 	framepos_t where = get_preferred_edit_position();
 
-	_session->begin_reversible_command (_("place transient"));
+	begin_reversible_command (_("place transient"));
-
+	
 	for (RegionSelection::iterator r = rs.begin(); r != rs.end(); ++r) {
 		framepos_t position = (*r)->region()->position();
 		(*r)->region()->add_transient(where - position);
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -6379,8 +6400,8 @@ Editor::snap_regions_to_grid ()
 		return;
 	}
 
-	_session->begin_reversible_command (_("snap regions to grid"));
+	begin_reversible_command (_("snap regions to grid"));
-
+	
 	for (RegionSelection::iterator r = rs.begin(); r != rs.end(); ++r) {
 
 		boost::shared_ptr<Playlist> pl = (*r)->region()->playlist();
@@ -6403,8 +6424,8 @@ Editor::snap_regions_to_grid ()
 		(*i)->thaw();
 		used_playlists.pop_front();
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -6462,8 +6483,8 @@ Editor::close_region_gaps ()
 
 	/* Iterate over the region list and make adjacent regions overlap by crossfade_len_ms */
 
-	_session->begin_reversible_command (_("close region gaps"));
+	begin_reversible_command (_("close region gaps"));
-
+	
 	int idx = 0;
 	boost::shared_ptr<Region> last_region;
 
@@ -6502,8 +6523,8 @@ Editor::close_region_gaps ()
 		(*i)->thaw();
 		used_playlists.pop_front();
 	}
-
+	
-	_session->commit_reversible_command ();
+	commit_reversible_command ();
 }
 
 void
@@ -7111,7 +7132,7 @@ Editor::toggle_region_mute ()
 
 		(*i)->region()->playlist()->clear_changes ();
 		(*i)->region()->set_muted (!(*i)->region()->muted ());
-		_session->add_command (new StatefulDiffCommand ((*i)->region()->playlist()));
+		_session->add_command (new StatefulDiffCommand ((*i)->region()));
 
 	}
 

gtk2_ardour/location_ui.cc

@@ -33,6 +33,7 @@
 #include "location_ui.h"
 #include "prompter.h"
 #include "utils.h"
+#include "public_editor.h"
 
 #include "i18n.h"
 
@@ -853,12 +854,12 @@ LocationUI::do_location_remove (ARDOUR::Location *loc)
 		return FALSE;
 	}
 
-	_session->begin_reversible_command (_("remove marker"));
+	PublicEditor::instance().begin_reversible_command (_("remove marker"));
 	XMLNode &before = _session->locations()->get_state();
 	_session->locations()->remove (loc);
 	XMLNode &after = _session->locations()->get_state();
 	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-	_session->commit_reversible_command ();
+	PublicEditor::instance().commit_reversible_command ();
 
 	return FALSE;
 }
@@ -1017,12 +1018,12 @@ LocationUI::add_new_location()
 		if (Config->get_name_new_markers()) {
 			newest_location = location;
 		}
-		_session->begin_reversible_command (_("add marker"));
+		PublicEditor::instance().begin_reversible_command (_("add marker"));
 		XMLNode &before = _session->locations()->get_state();
 		_session->locations()->add (location, true);
 		XMLNode &after = _session->locations()->get_state();
 		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-		_session->commit_reversible_command ();
+		PublicEditor::instance().commit_reversible_command ();
 	}
 
 }
@@ -1036,12 +1037,12 @@ LocationUI::add_new_range()
 		framepos_t where = _session->audible_frame();
 		_session->locations()->next_available_name(rangename,"unnamed");
 		Location *location = new Location (*_session, where, where, rangename, Location::IsRangeMarker);
-		_session->begin_reversible_command (_("add range marker"));
+		PublicEditor::instance().begin_reversible_command (_("add range marker"));
 		XMLNode &before = _session->locations()->get_state();
 		_session->locations()->add (location, true);
 		XMLNode &after = _session->locations()->get_state();
 		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
-		_session->commit_reversible_command ();
+		PublicEditor::instance().commit_reversible_command ();
 	}
 }
 

gtk2_ardour/midi_region_view.cc

@@ -3350,7 +3350,7 @@ MidiRegionView::selection_as_cut_buffer () const
 bool
 MidiRegionView::paste (framepos_t pos, const ::Selection& selection, PasteContext& ctx)
 {
-	trackview.session()->begin_reversible_command (Operations::paste);
+	trackview.editor().begin_reversible_command (Operations::paste);
 
 	// Paste notes, if available
 	MidiNoteSelection::const_iterator m = selection.midi_notes.get_nth(ctx.counts.n_notes());
@@ -3366,7 +3366,7 @@ MidiRegionView::paste (framepos_t pos, const ::Selection& selection, PasteContex
 		a->second->paste(pos, selection, ctx);
 	}
 
-	trackview.session()->commit_reversible_command ();
+	trackview.editor().commit_reversible_command ();
 
 	return true;
 }

gtk2_ardour/public_editor.h

@@ -245,6 +245,7 @@ class PublicEditor : public Gtk::Window, public PBD::StatefulDestructible, publi
 	virtual void set_zoom_focus (Editing::ZoomFocus) = 0;
 	virtual Editing::ZoomFocus get_zoom_focus () const = 0;
 	virtual framecnt_t get_current_zoom () const = 0;
+	virtual void reset_zoom (framecnt_t) = 0;
 	virtual PlaylistSelector& playlist_selector() const = 0;
 	virtual void clear_playlist (boost::shared_ptr<ARDOUR::Playlist>) = 0;
 	virtual void new_playlists (TimeAxisView*) = 0;
@@ -288,6 +289,8 @@ class PublicEditor : public Gtk::Window, public PBD::StatefulDestructible, publi
 	virtual void prepare_for_cleanup () = 0;
 	virtual void finish_cleanup () = 0;
 	virtual void reset_x_origin (framepos_t frame) = 0;
+	virtual double get_y_origin () const = 0;
+	virtual void reset_y_origin (double pos) = 0;
 	virtual void remove_last_capture () = 0;
 	virtual void maximise_editing_space () = 0;
 	virtual void restore_editing_space () = 0;
@@ -403,6 +406,10 @@ class PublicEditor : public Gtk::Window, public PBD::StatefulDestructible, publi
 	virtual void stop_canvas_autoscroll () = 0;
         virtual bool autoscroll_active() const = 0;
 
+	virtual void begin_reversible_command (std::string cmd_name) = 0;
+	virtual void begin_reversible_command (GQuark) = 0;
+	virtual void commit_reversible_command () = 0;
+
 	virtual MouseCursors const * cursors () const = 0;
 	virtual VerboseCursor * verbose_cursor () const = 0;
 
@@ -420,6 +427,7 @@ class PublicEditor : public Gtk::Window, public PBD::StatefulDestructible, publi
 
 	virtual void get_regions_at (RegionSelection &, framepos_t where, TrackViewList const &) const = 0;
 	virtual RegionSelection get_regions_from_selection_and_mouse (framepos_t) = 0;
+	virtual void get_regionviews_by_id (PBD::ID const & id, RegionSelection & regions) const = 0;
 
 	/// Singleton instance, set up by Editor::Editor()
 

gtk2_ardour/region_editor.cc

@@ -33,6 +33,7 @@
 #include "main_clock.h"
 #include "gui_thread.h"
 #include "region_editor.h"
+#include "public_editor.h"
 
 #include "i18n.h"
 
@@ -269,7 +270,7 @@ RegionEditor::connect_editor_events ()
 void
 RegionEditor::position_clock_changed ()
 {
-	_session->begin_reversible_command (_("change region start position"));
+	PublicEditor::instance().begin_reversible_command (_("change region start position"));
 
 	boost::shared_ptr<Playlist> pl = _region->playlist();
 
@@ -279,13 +280,13 @@ RegionEditor::position_clock_changed ()
 		_session->add_command(new StatefulDiffCommand (_region));
 	}
 
-	_session->commit_reversible_command ();
+	PublicEditor::instance().commit_reversible_command ();
 }
 
 void
 RegionEditor::end_clock_changed ()
 {
-	_session->begin_reversible_command (_("change region end position"));
+	PublicEditor::instance().begin_reversible_command (_("change region end position"));
 
 	boost::shared_ptr<Playlist> pl = _region->playlist();
 
@@ -295,7 +296,7 @@ RegionEditor::end_clock_changed ()
 		_session->add_command(new StatefulDiffCommand (_region));
 	}
 
-	_session->commit_reversible_command ();
+	PublicEditor::instance().commit_reversible_command ();
 
 	end_clock.set (_region->position() + _region->length() - 1, true);
 }
@@ -305,7 +306,7 @@ RegionEditor::length_clock_changed ()
 {
 	framecnt_t frames = length_clock.current_time();
 
-	_session->begin_reversible_command (_("change region length"));
+	PublicEditor::instance().begin_reversible_command (_("change region length"));
 
 	boost::shared_ptr<Playlist> pl = _region->playlist();
 
@@ -315,7 +316,7 @@ RegionEditor::length_clock_changed ()
 		_session->add_command(new StatefulDiffCommand (_region));
 	}
 
-	_session->commit_reversible_command ();
+	PublicEditor::instance().commit_reversible_command ();
 
 	length_clock.set (_region->length());
 }
@@ -399,25 +400,25 @@ RegionEditor::audition_state_changed (bool yn)
 void
 RegionEditor::sync_offset_absolute_clock_changed ()
 {
-	_session->begin_reversible_command (_("change region sync point"));
+	PublicEditor::instance().begin_reversible_command (_("change region sync point"));
 
         _region->clear_changes ();
 	_region->set_sync_position (sync_offset_absolute_clock.current_time());
 	_session->add_command (new StatefulDiffCommand (_region));
 
-	_session->commit_reversible_command ();
+	PublicEditor::instance().commit_reversible_command ();
 }
 
 void
 RegionEditor::sync_offset_relative_clock_changed ()
 {
-	_session->begin_reversible_command (_("change region sync point"));
+	PublicEditor::instance().begin_reversible_command (_("change region sync point"));
 
         _region->clear_changes ();
 	_region->set_sync_position (sync_offset_relative_clock.current_time() + _region->position ());
 	_session->add_command (new StatefulDiffCommand (_region));
 
-	_session->commit_reversible_command ();
+	PublicEditor::instance().commit_reversible_command ();
 }
 
 bool

gtk2_ardour/region_gain_line.cc

@@ -69,7 +69,7 @@ AudioRegionGainLine::start_drag_single (ControlPoint* cp, double x, float fracti
 void
 AudioRegionGainLine::remove_point (ControlPoint& cp)
 {
-	trackview.editor().session()->begin_reversible_command (_("remove control point"));
+	trackview.editor().begin_reversible_command (_("remove control point"));
 	XMLNode &before = alist->get_state();
 
 	if (!rv.audio_region()->envelope_active()) {
@@ -81,7 +81,7 @@ AudioRegionGainLine::remove_point (ControlPoint& cp)
 	alist->erase (cp.model());
 
 	trackview.editor().session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
-	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().commit_reversible_command ();
 	trackview.editor().session()->set_dirty ();
 }
 

gtk2_ardour/region_selection.cc

@@ -73,6 +73,7 @@ void
 RegionSelection::clear_all()
 {
 	clear();
+	pending.clear ();
 	_bylayer.clear();
 }
 

gtk2_ardour/region_selection.h

@@ -62,6 +62,7 @@ class RegionSelection : public std::list<RegionView*>
 	void  by_track (std::list<RegionView*>&) const;
 
 	std::set<boost::shared_ptr<ARDOUR::Playlist> > playlists () const;
+	std::list<PBD::ID> pending;
 
   private:
 	void remove_it (RegionView*);

gtk2_ardour/rhythm_ferret.cc

@@ -352,7 +352,7 @@ RhythmFerret::do_split_action ()
 
 	editor.EditorFreeze(); /* Emit signal */
 
-	_session->begin_reversible_command (_("split regions (rhythm ferret)"));
+	editor.begin_reversible_command (_("split regions (rhythm ferret)"));
 
 	/* Merge the transient positions for regions in consideration */
 	AnalysisFeatureList merged_features;
@@ -381,7 +381,7 @@ RhythmFerret::do_split_action ()
 		i = tmp;
 	}
 
-	_session->commit_reversible_command ();
+	editor.commit_reversible_command ();
 
 	editor.EditorThaw(); /* Emit signal */
 }

gtk2_ardour/selection.cc

@@ -1206,6 +1206,7 @@ Selection::get_state () const
 	   so that re-opening plugin windows for editor mixer strips works
 	*/
 
+	char buf[32];
 	XMLNode* node = new XMLNode (X_("Selection"));
 
 	for (TrackSelection::const_iterator i = tracks.begin(); i != tracks.end(); ++i) {
@@ -1221,9 +1222,23 @@ Selection::get_state () const
 		}
 	}
 
+	for (RegionSelection::const_iterator i = regions.begin(); i != regions.end(); ++i) {
+		XMLNode* r = node->add_child (X_("Region"));
+		r->add_property (X_("id"), atoi ((*i)->region ()->id ().to_s ().c_str()));
+		
+	}
+
+	for (TimeSelection::const_iterator i = time.begin(); i != time.end(); ++i) {
+		XMLNode* t = node->add_child (X_("AudioRange"));
+		snprintf(buf, sizeof(buf), "%ld", (*i).start);
+		t->add_property (X_("start"), string(buf));
+		snprintf(buf, sizeof(buf), "%ld", (*i).end);
+		t->add_property (X_("end"), string(buf));
+	}
+	
 	for (MarkerSelection::const_iterator i = markers.begin(); i != markers.end(); ++i) {
 		XMLNode* t = node->add_child (X_("Marker"));
-
+		
 		bool is_start;
 		Location* loc = editor->find_location_from_marker (*i, is_start);
 
@@ -1241,6 +1256,11 @@ Selection::set_state (XMLNode const & node, int)
 		return -1;
 	}
 
+	clear_regions ();
+	clear_time ();
+	clear_tracks ();
+	clear_markers ();
+
 	XMLNodeList children = node.children ();
 	for (XMLNodeList::const_iterator i = children.begin(); i != children.end(); ++i) {
 		if ((*i)->name() == X_("RouteView")) {
@@ -1253,6 +1273,36 @@ Selection::set_state (XMLNode const & node, int)
 				add (rtv);
 			}
 
+		} else if ((*i)->name() == X_("Region")) {
+			XMLProperty* prop_id = (*i)->property (X_("id"));
+			assert (prop_id);
+			PBD::ID id (prop_id->value ());
+			
+			RegionSelection rs;
+			editor->get_regionviews_by_id (id, rs);
+			
+			if (!rs.empty ()) {
+				add (rs);
+			} else {
+				/*
+				  regionviews are being constructed - stash the region IDs 
+				  so we can identify them in Editor::region_view_added ()
+				*/
+				regions.pending.push_back (id);
+			}
+			
+		} else if  ((*i)->name() == X_("AudioRange")) {
+			XMLProperty* prop_start = (*i)->property (X_("start"));
+			XMLProperty* prop_end = (*i)->property (X_("end"));
+
+			assert (prop_start);
+			assert (prop_end);
+
+			framepos_t s (atol (prop_start->value ().c_str()));
+			framepos_t e (atol (prop_end->value ().c_str()));
+
+			set_preserving_all_ranges (s, e);
+
 		} else if ((*i)->name() == X_("AutomationView")) {
 
 			XMLProperty* prop_id = (*i)->property (X_("id"));

gtk2_ardour/selection_memento.cc

@@ -0,0 +1,95 @@
+/*
+    Copyright (C) 2014 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "selection_memento.h"
+#include "editing.h"
+#include "public_editor.h"
+
+#include "i18n.h"
+
+SelectionMemento::SelectionMemento ()
+{
+}
+
+SelectionMemento::~SelectionMemento ()
+{
+}
+
+XMLNode&
+SelectionMemento::get_state () {
+
+	XMLNode* node = new XMLNode ("SelectionMemento");
+	char buf[32];
+	PublicEditor& editor = PublicEditor::instance();
+
+	node->add_property ("mouse-mode", enum2str(editor.current_mouse_mode()));
+	snprintf (buf, sizeof(buf), "%" PRId64, editor.get_current_zoom());
+	node->add_property ("zoom", buf);
+	snprintf (buf, sizeof (buf), "%" PRIi64, editor.leftmost_sample());
+	node->add_property ("left-frame", buf);
+	snprintf (buf, sizeof (buf), "%f", editor.get_y_origin());
+	node->add_property ("y-origin", buf);
+
+	node->add_child_nocopy (editor.get_selection().get_state());
+	return *node;
+}
+
+int
+SelectionMemento::set_state (const XMLNode& node, int /*version*/) {
+
+	const XMLProperty* prop;
+	PublicEditor& editor = PublicEditor::instance();
+	if (node.name() != X_("SelectionMemento")) {
+		return -1;
+	}
+
+	if ((prop = node.property ("mouse-mode"))) {
+		Editing::MouseMode m = Editing::str2mousemode(prop->value());
+		editor.set_mouse_mode (m, true);
+	} else {
+		editor.set_mouse_mode (Editing::MouseObject, true);
+	}
+
+	if ((prop = node.property ("zoom"))) {
+		/* older versions of ardour used floating point samples_per_pixel */
+		double f = PBD::atof (prop->value());
+		editor.reset_zoom (llrintf (f));
+	}
+
+	if ((prop = node.property ("left-frame")) != 0) {
+		framepos_t pos;
+		if (sscanf (prop->value().c_str(), "%" PRId64, &pos) == 1) {
+			if (pos < 0) {
+				pos = 0;
+			}
+			editor.reset_x_origin (pos);
+		}
+	}
+
+	if ((prop = node.property ("y-origin")) != 0) {
+		editor.reset_y_origin (atof (prop->value ().c_str()));
+	}
+
+	XMLNodeList children = node.children ();
+	for (XMLNodeList::const_iterator i = children.begin(); i != children.end(); ++i) {
+		editor.get_selection().set_state (**i, Stateful::current_state_version);
+	}
+
+	return 0;
+}

gtk2_ardour/selection_memento.h

@@ -0,0 +1,34 @@
+/*
+    Copyright (C) 2014 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#ifndef __ardour_gtk_selection_memento_h__
+#define __ardour_gtk_selection_memento_h__
+
+#include "pbd/statefuldestructible.h"
+
+class SelectionMemento : public PBD::StatefulDestructible
+{
+public:
+	SelectionMemento ();
+	~SelectionMemento ();
+
+	XMLNode& get_state ();
+	int set_state (const XMLNode&, int version);
+};
+#endif /* __ardour_gtk_selection_memento_h__ */

gtk2_ardour/wscript

@@ -201,6 +201,7 @@ gtk2_ardour_sources = [
         'ruler_dialog.cc',
         'search_path_option.cc',
         'selection.cc',
+        'selection_memento.cc',
         'send_ui.cc',
         'session_dialog.cc',
         'session_import_dialog.cc',