Stop ardour exiting in the case where you have a loaded session, then select New...
[ardour.git] / gtk2_ardour / midi_region_view.cc
index f87cc50d4ede264ef6c44182423a0782ee398b2e..40f267717b6d03c9337c4a1acf9def2dd97e006b 100644 (file)
@@ -82,9 +82,12 @@ MidiRegionView::MidiRegionView (ArdourCanvas::Group *parent, RouteTimeAxisView &
        , _custom_device_mode(string())
        , _active_notes(0)
        , _note_group(new ArdourCanvas::Group(*parent))
-       , _delta_command(NULL)
+       , _delta_command(0)
+       , _diff_command(0)
        , _mouse_state(None)
        , _pressed_button(0)
+       , _sort_needed (true)
+       , _optimization_iterator (_events.end())
 {
        _note_group->raise_to_top();
 }
@@ -100,10 +103,13 @@ MidiRegionView::MidiRegionView (ArdourCanvas::Group *parent, RouteTimeAxisView &
        , _custom_device_mode(string())
        , _active_notes(0)
        , _note_group(new ArdourCanvas::Group(*parent))
-       , _delta_command(NULL)
+       , _delta_command(0)
+       , _diff_command(0)
        , _mouse_state(None)
        , _pressed_button(0)
-       
+       , _sort_needed (true)
+       , _optimization_iterator (_events.end())
+
 {
        _note_group->raise_to_top();
 }
@@ -119,16 +125,19 @@ MidiRegionView::MidiRegionView (const MidiRegionView& other)
        , _custom_device_mode(string())
        , _active_notes(0)
        , _note_group(new ArdourCanvas::Group(*get_canvas_group()))
-       , _delta_command(NULL)
+       , _delta_command(0)
+       , _diff_command(0)
        , _mouse_state(None)
        , _pressed_button(0)
+       , _sort_needed (true)
+       , _optimization_iterator (_events.end())
 {
        Gdk::Color c;
        int r,g,b,a;
 
        UINT_TO_RGBA (other.fill_color, &r, &g, &b, &a);
        c.set_rgb_p (r/255.0, g/255.0, b/255.0);
-       
+
        init (c, false);
 }
 
@@ -141,9 +150,12 @@ MidiRegionView::MidiRegionView (const MidiRegionView& other, boost::shared_ptr<M
        , _custom_device_mode(string())
        , _active_notes(0)
        , _note_group(new ArdourCanvas::Group(*get_canvas_group()))
-       , _delta_command(NULL)
+       , _delta_command(0)
+       , _diff_command(0)
        , _mouse_state(None)
        , _pressed_button(0)
+       , _sort_needed (true)
+       , _optimization_iterator (_events.end())
 {
        Gdk::Color c;
        int r,g,b,a;
@@ -174,7 +186,7 @@ MidiRegionView::init (Gdk::Color const & basic_color, bool wfd)
        region_sync_changed ();
        region_resized (BoundsChanged);
        region_locked ();
-       
+
        reset_width_dependent_items (_pixel_width);
 
        set_colors ();
@@ -191,7 +203,7 @@ MidiRegionView::init (Gdk::Color const & basic_color, bool wfd)
 
        midi_view()->signal_channel_mode_changed().connect(
                        mem_fun(this, &MidiRegionView::midi_channel_mode_changed));
-       
+
        midi_view()->signal_midi_patch_settings_changed().connect(
                        mem_fun(this, &MidiRegionView::midi_patch_settings_changed));
 }
@@ -211,7 +223,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
        nframes64_t event_frame = 0;
        bool fine;
 
-       static ArdourCanvas::SimpleRect* drag_rect = NULL;
+       static ArdourCanvas::SimpleRect* drag_rect = 0;
 
        /* XXX: note that as of August 2009, the GnomeCanvas does not propagate scroll events
           to its items, which means that ev->type == GDK_SCROLL will never be seen
@@ -220,7 +232,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
        switch (ev->type) {
        case GDK_SCROLL:
                fine = Keyboard::modifier_state_equals (ev->scroll.state, Keyboard::Level4Modifier);
-               
+
                if (ev->scroll.direction == GDK_SCROLL_UP) {
                        change_velocities (true, fine, false);
                        return true;
@@ -253,7 +265,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                        bool end = (ev->key.keyval == GDK_period);
                        bool shorter = Keyboard::modifier_state_contains (ev->key.state, Keyboard::PrimaryModifier);
                        fine = Keyboard::modifier_state_contains (ev->key.state, Keyboard::SecondaryModifier);
-                       
+
                        change_note_lengths (fine, shorter, start, end);
 
                        return true;
@@ -285,10 +297,10 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                        return true;
 
                } else if (ev->key.keyval == GDK_Down) {
-                       
+
                        bool allow_smush = Keyboard::modifier_state_contains (ev->key.state, Keyboard::SecondaryModifier);
                        fine = Keyboard::modifier_state_contains (ev->key.state, Keyboard::TertiaryModifier);
-                       
+
                        if (Keyboard::modifier_state_contains (ev->key.state, Keyboard::PrimaryModifier)) {
                                change_velocities (false, fine, allow_smush);
                        } else {
@@ -297,7 +309,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                        return true;
 
                } else if (ev->key.keyval == GDK_Left) {
-                       
+
                        nudge_notes (false);
                        return true;
 
@@ -309,7 +321,12 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                } else if (ev->key.keyval == GDK_Control_L) {
                        return true;
 
+               } else if (ev->key.keyval == GDK_r) {
+                       /* if we're not step editing, this really doesn't matter */
+                       midi_view()->step_edit_rest ();
+                       return true;
                }
+
                return false;
 
        case GDK_KEY_RELEASE:
@@ -454,7 +471,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                } else if (_pressed_button != 1) {
                        return false;
                }
-                       
+
                switch (_mouse_state) {
                case Pressed: // Clicked
                        switch (editor.current_mouse_mode()) {
@@ -465,7 +482,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                        case MouseRange:
                                create_note_at(event_x, event_y, _default_note_length);
                                break;
-                       default: 
+                       default:
                                break;
                        }
                        _mouse_state = None;
@@ -473,7 +490,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                case SelectRectDragging: // Select drag done
                        _mouse_state = None;
                        delete drag_rect;
-                       drag_rect = NULL;
+                       drag_rect = 0;
                        break;
                case AddDragging: // Add drag done
                        _mouse_state = None;
@@ -481,15 +498,15 @@ MidiRegionView::canvas_event(GdkEvent* ev)
                                const double x      = drag_rect->property_x1();
                                const double length = trackview.editor().pixel_to_frame(
                                                        drag_rect->property_x2() - drag_rect->property_x1());
-                                       
+
                                create_note_at(x, drag_rect->property_y1(), frames_to_beats(length));
                        }
 
                        delete drag_rect;
-                       drag_rect = NULL;
+                       drag_rect = 0;
                default: break;
                }
-               
+
        default: break;
        }
 
@@ -558,6 +575,7 @@ MidiRegionView::clear_events()
        _events.clear();
        _pgm_changes.clear();
        _sys_exes.clear();
+       _optimization_iterator = _events.end();
 }
 
 
@@ -567,13 +585,14 @@ MidiRegionView::display_model(boost::shared_ptr<MidiModel> model)
        _model = model;
        content_connection.disconnect ();
        content_connection = _model->ContentsChanged.connect(sigc::mem_fun(this, &MidiRegionView::redisplay_model));
+       clear_events ();
 
        if (_enable_display) {
                redisplay_model();
        }
 }
-       
-       
+
+
 void
 MidiRegionView::start_delta_command(string name)
 {
@@ -613,7 +632,7 @@ MidiRegionView::delta_remove_note(ArdourCanvas::CanvasNoteEvent* ev)
 }
 
 void
-MidiRegionView::diff_add_change (ArdourCanvas::CanvasNoteEvent* ev, 
+MidiRegionView::diff_add_change (ArdourCanvas::CanvasNoteEvent* ev,
                                 MidiModel::DiffCommand::Property property,
                                 uint8_t val)
 {
@@ -623,7 +642,7 @@ MidiRegionView::diff_add_change (ArdourCanvas::CanvasNoteEvent* ev,
 }
 
 void
-MidiRegionView::diff_add_change (ArdourCanvas::CanvasNoteEvent* ev, 
+MidiRegionView::diff_add_change (ArdourCanvas::CanvasNoteEvent* ev,
                                 MidiModel::DiffCommand::Property property,
                                 Evoral::MusicalTime val)
 {
@@ -631,7 +650,7 @@ MidiRegionView::diff_add_change (ArdourCanvas::CanvasNoteEvent* ev,
                _diff_command->change (ev->note(), property, val);
        }
 }
-       
+
 void
 MidiRegionView::apply_delta()
 {
@@ -643,9 +662,9 @@ MidiRegionView::apply_delta()
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
                _marked_for_selection.insert((*i)->note());
        }
-       
+
        _model->apply_command(trackview.session(), _delta_command);
-       _delta_command = NULL; 
+       _delta_command = 0;
        midi_view()->midi_track()->diskstream()->playlist_modified();
 
        _marked_for_selection.clear();
@@ -659,16 +678,10 @@ MidiRegionView::apply_diff ()
                return;
        }
 
-       // Mark all selected notes for selection when model reloads
-       for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
-               _marked_for_selection.insert((*i)->note());
-       }
-       
        _model->apply_command(trackview.session(), _diff_command);
-       _diff_command = NULL; 
+       _diff_command = 0;
        midi_view()->midi_track()->diskstream()->playlist_modified();
 
-       _marked_for_selection.clear();
        _marked_for_velocity.clear();
 }
 
@@ -683,9 +696,9 @@ MidiRegionView::apply_delta_as_subcommand()
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
                _marked_for_selection.insert((*i)->note());
        }
-       
+
        _model->apply_command_as_subcommand(trackview.session(), _delta_command);
-       _delta_command = NULL; 
+       _delta_command = 0;
        midi_view()->midi_track()->diskstream()->playlist_modified();
 
        _marked_for_selection.clear();
@@ -703,9 +716,9 @@ MidiRegionView::apply_diff_as_subcommand()
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
                _marked_for_selection.insert((*i)->note());
        }
-       
+
        _model->apply_command_as_subcommand(trackview.session(), _diff_command);
-       _diff_command = NULL; 
+       _diff_command = 0;
        midi_view()->midi_track()->diskstream()->playlist_modified();
 
        _marked_for_selection.clear();
@@ -722,6 +735,26 @@ MidiRegionView::abort_command()
        clear_selection();
 }
 
+CanvasNoteEvent*
+MidiRegionView::find_canvas_note (boost::shared_ptr<NoteType> note)
+{
+       if (_optimization_iterator != _events.end()) {
+               ++_optimization_iterator;
+       }
+
+       if (_optimization_iterator != _events.end() && (*_optimization_iterator)->note() == note) {
+               return *_optimization_iterator;
+       }
+
+       for (_optimization_iterator = _events.begin(); _optimization_iterator != _events.end(); ++_optimization_iterator) {
+               if ((*_optimization_iterator)->note() == note) {
+                       return *_optimization_iterator;
+               }
+       }
+
+       return 0;
+}
+
 void
 MidiRegionView::redisplay_model()
 {
@@ -730,34 +763,86 @@ MidiRegionView::redisplay_model()
                return;
        }
 
-       if (_model) {
+       if (!_model) {
+               cerr << "MidiRegionView::redisplay_model called without a model" << endmsg;
+               return;
+       }
 
-               // Mark all selected notes for selection when model reloads
-               for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
-                       _marked_for_selection.insert((*i)->note());
-               }
-               
-
-               clear_events();
-               _model->read_lock();
-               
-               MidiModel::Notes notes = _model->notes();
-               
-               for (size_t i = 0; i < _model->n_notes(); ++i) {
-                       boost::shared_ptr<NoteType> note (_model->note_at (i));
-                       if (note_in_visible_range (note)) {
-                               add_note (note);
+       for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
+               (*i)->invalidate ();
+       }
+
+       _model->read_lock();
+
+       MidiModel::Notes& notes (_model->notes());
+       _optimization_iterator = _events.begin();
+
+       for (MidiModel::Notes::iterator n = notes.begin(); n != notes.end(); ++n) {
+
+               boost::shared_ptr<NoteType> note (*n);
+               CanvasNoteEvent* cne;
+               bool visible;
+
+               if (note_in_region_range (note, visible)) {
+
+                       if ((cne = find_canvas_note (note)) != 0) {
+
+                               cne->validate ();
+
+                               CanvasNote* cn;
+                               CanvasHit* ch;
+
+                               if ((cn = dynamic_cast<CanvasNote*>(cne)) != 0) {
+                                       update_note (cn);
+                               } else if ((ch = dynamic_cast<CanvasHit*>(cne)) != 0) {
+                                       update_hit (ch);
+                               }
+
+                               if (visible) {
+                                       cne->show ();
+                               } else {
+                                       cne->hide ();
+                               }
+
+                       } else {
+
+                               add_note (note, visible);
+                       }
+
+               } else {
+
+                       if ((cne = find_canvas_note (note)) != 0) {
+                               cne->validate ();
+                               cne->hide ();
                        }
                }
-               
-               display_sysexes();
-               display_program_changes();
+       }
 
-               _model->read_unlock();
+       /* remove note items that are no longer valid */
 
-       } else {
-               cerr << "MidiRegionView::redisplay_model called without a model" << endmsg;
+       for (Events::iterator i = _events.begin(); i != _events.end(); ) {
+               if (!(*i)->valid ()) {
+                       delete *i;
+                       i = _events.erase (i);
+               } else {
+                       ++i;
+               }
        }
+
+       display_sysexes();
+       display_program_changes();
+
+       _model->read_unlock();
+
+       _marked_for_selection.clear ();
+       _marked_for_velocity.clear ();
+
+       /* we may have caused _events to contain things out of order (e.g. if a note
+          moved earlier or later). we don't generally need them in time order, but
+          make a note that a sort is required for those cases that require it.
+       */
+
+       _sort_needed = true;
 }
 
 void
@@ -795,7 +880,7 @@ MidiRegionView::display_program_changes()
 
                MIDI::Name::PatchPrimaryKey patch_key(msb, lsb, program_number);
 
-               boost::shared_ptr<MIDI::Name::Patch> patch = 
+               boost::shared_ptr<MIDI::Name::Patch> patch =
                        MIDI::Name::MidiPatchManager::instance().find_patch(
                                        _model_name, _custom_device_mode, channel, patch_key);
 
@@ -811,13 +896,13 @@ MidiRegionView::display_program_changes()
        }
 }
 
-void 
+void
 MidiRegionView::display_sysexes()
 {
        for (MidiModel::SysExes::const_iterator i = _model->sysexes().begin(); i != _model->sysexes().end(); ++i) {
                Evoral::MusicalTime time = (*i)->time();
                assert(time >= 0);
-               
+
                ostringstream str;
                str << hex;
                for (uint32_t b = 0; b < (*i)->size(); ++b) {
@@ -827,23 +912,23 @@ MidiRegionView::display_sysexes()
                        }
                }
                string text = str.str();
-               
+
                ArdourCanvas::Group* const group = (ArdourCanvas::Group*)get_canvas_group();
 
                const double x = trackview.editor().frame_to_pixel(beats_to_frames(time));
-               
+
                double height = midi_stream_view()->contents_height();
-               
+
                boost::shared_ptr<CanvasSysEx> sysex = boost::shared_ptr<CanvasSysEx>(
                                new CanvasSysEx(*this, *group, text, height, x, 1.0));
-               
+
                // Show unless program change is beyond the region bounds
                if (time - _region->start() >= _region->length() || time < _region->start()) {
                        sysex->hide();
                } else {
                        sysex->show();
                }
-               
+
                _sys_exes.push_back(sysex);
        }
 }
@@ -869,13 +954,13 @@ void
 MidiRegionView::region_resized (Change what_changed)
 {
        RegionView::region_resized(what_changed);
-       
+
        if (what_changed & ARDOUR::PositionChanged) {
                set_duration(_region->length(), 0);
                if (_enable_display) {
                        redisplay_model();
                }
-       } 
+       }
 }
 
 void
@@ -896,11 +981,11 @@ MidiRegionView::set_height (double height)
        const double old_height = _height;
        RegionView::set_height(height);
        _height = height - FUDGE;
-       
+
        apply_note_range(midi_stream_view()->lowest_note(),
                         midi_stream_view()->highest_note(),
                         height != old_height + FUDGE);
-       
+
        if (name_pixbuf) {
                name_pixbuf->raise_to_top();
        }
@@ -920,46 +1005,42 @@ MidiRegionView::apply_note_range (uint8_t min, uint8_t max, bool force)
        if (!force && _current_range_min == min && _current_range_max == max) {
                return;
        }
-       
+
        _current_range_min = min;
        _current_range_max = max;
 
        for (Events::const_iterator i = _events.begin(); i != _events.end(); ++i) {
                CanvasNoteEvent* event = *i;
-               Item* item = dynamic_cast<Item*>(event);
-               assert(item);
-               if (event && event->note()) {
-                       if (event->note()->note() < _current_range_min
-                                       || event->note()->note() > _current_range_max) {
-                               if (canvas_item_visible(item)) {
-                                       item->hide();
-                               }
-                       } else {
-                               if (!canvas_item_visible(item)) {
-                                       item->show();
-                               }
+               boost::shared_ptr<NoteType> note (event->note());
 
-                               if (CanvasNote* note = dynamic_cast<CanvasNote*>(event)) {
-                                       const double y1 = midi_stream_view()->note_to_y(event->note()->note());
-                                       const double y2 = y1 + floor(midi_stream_view()->note_height());
-
-                                       note->property_y1() = y1;
-                                       note->property_y2() = y2;
-                               } else if (CanvasHit* hit = dynamic_cast<CanvasHit*>(event)) {
-                                       double x = trackview.editor().frame_to_pixel(
-                                                       beats_to_frames(event->note()->time()) - _region->start());
-                                       const double diamond_size = midi_stream_view()->note_height() / 2.0;
-                                       double y = midi_stream_view()->note_to_y(event->note()->note()) 
-                                                        + ((diamond_size-2.0) / 4.0);
-                                       
-                                       hit->set_height(diamond_size);
-                                       hit->move(x-hit->x1(), y-hit->y1());
-                                       hit->show();
-                               }
-                       }
+               if (note->note() < _current_range_min ||
+                   note->note() > _current_range_max) {
+                       event->hide();
+               } else {
+                       event->show();
+               }
+
+               if (CanvasNote* cnote = dynamic_cast<CanvasNote*>(event)) {
+
+                       const double y1 = midi_stream_view()->note_to_y(note->note());
+                       const double y2 = y1 + floor(midi_stream_view()->note_height());
+
+                       cnote->property_y1() = y1;
+                       cnote->property_y2() = y2;
+
+               } else if (CanvasHit* chit = dynamic_cast<CanvasHit*>(event)) {
+
+                       double x = trackview.editor().frame_to_pixel(
+                               beats_to_frames(note->time()) - _region->start());
+                       const double diamond_size = midi_stream_view()->note_height() / 2.0;
+                       double y = midi_stream_view()->note_to_y(event->note()->note())
+                               + ((diamond_size-2.0) / 4.0);
+
+                       chit->set_height (diamond_size);
+                       chit->move (x - chit->x1(), y - chit->y1());
+                       chit->show ();
                }
        }
-       
 }
 
 GhostRegion*
@@ -1004,7 +1085,7 @@ MidiRegionView::begin_write()
        assert(!_active_notes);
        _active_notes = new CanvasNote*[128];
        for (unsigned i=0; i < 128; ++i) {
-               _active_notes[i] = NULL;
+               _active_notes[i] = 0;
        }
 }
 
@@ -1015,7 +1096,7 @@ void
 MidiRegionView::end_write()
 {
        delete[] _active_notes;
-       _active_notes = NULL;
+       _active_notes = 0;
        _marked_for_selection.clear();
        _marked_for_velocity.clear();
 }
@@ -1034,7 +1115,7 @@ MidiRegionView::resolve_note(uint8_t note, double end_time)
                const nframes64_t end_time_frames = beats_to_frames(end_time);
                _active_notes[note]->property_x2() = trackview.editor().frame_to_pixel(end_time_frames);
                _active_notes[note]->property_outline_what() = (guint32) 0xF; // all edges
-               _active_notes[note] = NULL;
+               _active_notes[note] = 0;
        }
 }
 
@@ -1055,7 +1136,7 @@ MidiRegionView::extend_active_notes()
        }
 }
 
-void 
+void
 MidiRegionView::play_midi_note(boost::shared_ptr<NoteType> note)
 {
        if (!trackview.editor().sound_notes()) {
@@ -1064,10 +1145,10 @@ MidiRegionView::play_midi_note(boost::shared_ptr<NoteType> note)
 
        RouteUI* route_ui = dynamic_cast<RouteUI*> (&trackview);
        assert(route_ui);
-       
+
        route_ui->midi_track()->write_immediate_event(
                        note->on_event().size(), note->on_event().buffer());
-       
+
        const double note_length_beats = (note->off_event().time() - note->on_event().time());
        nframes_t note_length_ms = beats_to_frames(note_length_beats)
                        * (1000 / (double)route_ui->session().nominal_frame_rate());
@@ -1080,7 +1161,7 @@ MidiRegionView::play_midi_note_off(boost::shared_ptr<NoteType> note)
 {
        RouteUI* route_ui = dynamic_cast<RouteUI*> (&trackview);
        assert(route_ui);
-       
+
        route_ui->midi_track()->write_immediate_event(
                        note->off_event().size(), note->off_event().buffer());
 
@@ -1088,16 +1169,75 @@ MidiRegionView::play_midi_note_off(boost::shared_ptr<NoteType> note)
 }
 
 bool
-MidiRegionView::note_in_visible_range(const boost::shared_ptr<NoteType> note) const
+MidiRegionView::note_in_region_range(const boost::shared_ptr<NoteType> note, bool& visible) const
 {
        const nframes64_t note_start_frames = beats_to_frames(note->time());
-       bool outside = (note_start_frames - _region->start() >= _region->length())
-                       || (note_start_frames < _region->start())
-                       || (note->note() < midi_stream_view()->lowest_note())
-                       || (note->note() > midi_stream_view()->highest_note());
+
+       bool outside = (note_start_frames - _region->start() >= _region->length()) ||
+               (note_start_frames < _region->start());
+
+       visible = (note->note() >= midi_stream_view()->lowest_note()) &&
+               (note->note() <= midi_stream_view()->highest_note());
+
        return !outside;
 }
 
+void
+MidiRegionView::update_note (CanvasNote* ev)
+{
+       boost::shared_ptr<NoteType> note = ev->note();
+
+       const nframes64_t note_start_frames = beats_to_frames(note->time());
+       const nframes64_t note_end_frames   = beats_to_frames(note->end_time());
+
+       const double x = trackview.editor().frame_to_pixel(note_start_frames - _region->start());
+       const double y1 = midi_stream_view()->note_to_y(note->note());
+       const double note_endpixel =
+               trackview.editor().frame_to_pixel(note_end_frames - _region->start());
+
+       ev->property_x1() = x;
+       ev->property_y1() = y1;
+       if (note->length() > 0) {
+               ev->property_x2() = note_endpixel;
+       } else {
+               ev->property_x2() = trackview.editor().frame_to_pixel(_region->length());
+       }
+       ev->property_y2() = y1 + floor(midi_stream_view()->note_height());
+
+       if (note->length() == 0) {
+               if (_active_notes) {
+                       assert(note->note() < 128);
+                       // If this note is already active there's a stuck note,
+                       // finish the old note rectangle
+                       if (_active_notes[note->note()]) {
+                               CanvasNote* const old_rect = _active_notes[note->note()];
+                               boost::shared_ptr<NoteType> old_note = old_rect->note();
+                               old_rect->property_x2() = x;
+                               old_rect->property_outline_what() = (guint32) 0xF;
+                       }
+                       _active_notes[note->note()] = ev;
+               }
+               /* outline all but right edge */
+               ev->property_outline_what() = (guint32) (0x1 & 0x4 & 0x8);
+       } else {
+               /* outline all edges */
+               ev->property_outline_what() = (guint32) 0xF;
+       }
+}
+
+void
+MidiRegionView::update_hit (CanvasHit* ev)
+{
+       boost::shared_ptr<NoteType> note = ev->note();
+
+       const nframes64_t note_start_frames = beats_to_frames(note->time());
+       const double x = trackview.editor().frame_to_pixel(note_start_frames - _region->start());
+       const double diamond_size = midi_stream_view()->note_height() / 2.0;
+       const double y = midi_stream_view()->note_to_y(note->note()) + ((diamond_size-2) / 4.0);
+
+       ev->move_to (x, y);
+}
+
 /** Add a MIDI note to the view (with length).
  *
  * If in sustained mode, notes with length 0 will be considered active
@@ -1105,58 +1245,25 @@ MidiRegionView::note_in_visible_range(const boost::shared_ptr<NoteType> note) co
  * event arrives, to properly display the note.
  */
 void
-MidiRegionView::add_note(const boost::shared_ptr<NoteType> note)
+MidiRegionView::add_note(const boost::shared_ptr<NoteType> note, bool visible)
 {
+       CanvasNoteEvent* event = 0;
+
        assert(note->time() >= 0);
        assert(midi_view()->note_mode() == Sustained || midi_view()->note_mode() == Percussive);
 
-       const nframes64_t note_start_frames = beats_to_frames(note->time());
-       const nframes64_t note_end_frames   = beats_to_frames(note->end_time());
-
        ArdourCanvas::Group* const group = (ArdourCanvas::Group*)get_canvas_group();
 
-       CanvasNoteEvent* event = 0;
-       
-       const double x = trackview.editor().frame_to_pixel(note_start_frames - _region->start());
-       
        if (midi_view()->note_mode() == Sustained) {
-               const double y1 = midi_stream_view()->note_to_y(note->note());
-               const double note_endpixel = 
-                       trackview.editor().frame_to_pixel(note_end_frames - _region->start());
-               
+
                CanvasNote* ev_rect = new CanvasNote(*this, *group, note);
-               ev_rect->property_x1() = x;
-               ev_rect->property_y1() = y1;
-               if (note->length() > 0) {
-                       ev_rect->property_x2() = note_endpixel;
-               } else {
-                       ev_rect->property_x2() = trackview.editor().frame_to_pixel(_region->length());
-               }
-               ev_rect->property_y2() = y1 + floor(midi_stream_view()->note_height());
-
-               if (note->length() == 0) {
-                       if (_active_notes) {
-                               assert(note->note() < 128);
-                               // If this note is already active there's a stuck note,
-                               // finish the old note rectangle
-                               if (_active_notes[note->note()]) {
-                                       CanvasNote* const old_rect = _active_notes[note->note()];
-                                       boost::shared_ptr<NoteType> old_note = old_rect->note();
-                                       old_rect->property_x2() = x;
-                                       old_rect->property_outline_what() = (guint32) 0xF;
-                               }
-                               _active_notes[note->note()] = ev_rect;
-                       }
-                       /* outline all but right edge */
-                       ev_rect->property_outline_what() = (guint32) (0x1 & 0x4 & 0x8);
-               } else {
-                       /* outline all edges */
-                       ev_rect->property_outline_what() = (guint32) 0xF;
-               }
+
+               update_note (ev_rect);
 
                event = ev_rect;
 
                MidiGhostRegion* gr;
+
                for (std::vector<GhostRegion*>::iterator g = ghosts.begin(); g != ghosts.end(); ++g) {
                        if ((gr = dynamic_cast<MidiGhostRegion*>(*g)) != 0) {
                                gr->add_note(ev_rect);
@@ -1164,12 +1271,15 @@ MidiRegionView::add_note(const boost::shared_ptr<NoteType> note)
                }
 
        } else if (midi_view()->note_mode() == Percussive) {
+
                const double diamond_size = midi_stream_view()->note_height() / 2.0;
-               const double y = midi_stream_view()->note_to_y(note->note()) + ((diamond_size-2) / 4.0);
 
                CanvasHit* ev_diamond = new CanvasHit(*this, *group, diamond_size, note);
-               ev_diamond->move(x, y);
+
+               update_hit (ev_diamond);
+
                event = ev_diamond;
+
        } else {
                event = 0;
        }
@@ -1177,7 +1287,7 @@ MidiRegionView::add_note(const boost::shared_ptr<NoteType> note)
        if (event) {
                if (_marked_for_selection.find(note) != _marked_for_selection.end()) {
                        note_selected(event, true);
-               } 
+               }
 
                if (_marked_for_velocity.find(note) != _marked_for_velocity.end()) {
                        event->show_velocity();
@@ -1185,7 +1295,7 @@ MidiRegionView::add_note(const boost::shared_ptr<NoteType> note)
                event->on_channel_selection_change(_last_channel_selection);
                _events.push_back(event);
 
-               if (note_in_visible_range(note)) {
+               if (visible) {
                        event->show();
                } else {
                        event->hide ();
@@ -1193,32 +1303,54 @@ MidiRegionView::add_note(const boost::shared_ptr<NoteType> note)
        }
 }
 
+void
+MidiRegionView::add_note (uint8_t channel, uint8_t number, uint8_t velocity,
+                         Evoral::MusicalTime pos, Evoral::MusicalTime len)
+{
+       boost::shared_ptr<NoteType> new_note (new NoteType (channel, pos, len, number, velocity));
+
+       start_delta_command (_("step add"));
+       delta_add_note (new_note, true, false);
+       apply_delta();
+
+       /* potentially extend region to hold new note */
+
+       nframes64_t end_frame = _region->position() + beats_to_frames (new_note->end_time());
+       nframes64_t region_end = _region->position() + _region->length() - 1;
+
+       if (end_frame > region_end) {
+               _region->set_length (end_frame, this);
+       } else {
+               redisplay_model ();
+       }
+}
+
 void
 MidiRegionView::add_pgm_change(PCEvent& program, const string& displaytext)
 {
        assert(program.time >= 0);
-       
+
        ArdourCanvas::Group* const group = (ArdourCanvas::Group*)get_canvas_group();
        const double x = trackview.editor().frame_to_pixel(beats_to_frames(program.time));
-       
+
        double height = midi_stream_view()->contents_height();
-       
+
        boost::shared_ptr<CanvasProgramChange> pgm_change = boost::shared_ptr<CanvasProgramChange>(
                        new CanvasProgramChange(*this, *group,
-                                       displaytext, 
-                                       height, 
-                                       x, 1.0, 
-                                       _model_name, 
-                                       _custom_device_mode, 
+                                       displaytext,
+                                       height,
+                                       x, 1.0,
+                                       _model_name,
+                                       _custom_device_mode,
                                        program.time, program.channel, program.value));
-       
+
        // Show unless program change is beyond the region bounds
        if (program.time - _region->start() >= _region->length() || program.time < _region->start()) {
                pgm_change->hide();
        } else {
                pgm_change->show();
        }
-       
+
        _pgm_changes.push_back(pgm_change);
 }
 
@@ -1241,7 +1373,7 @@ MidiRegionView::get_patch_key_at(double time, uint8_t channel, MIDI::Name::Patch
                lsb = lsb_control->get_float(true, time);
                cerr << " got lsb " << lsb;
        }
-       
+
        Evoral::Parameter program_change(MidiPgmChangeAutomation, channel, 0);
        boost::shared_ptr<Evoral::Control> program_control = _model->control(program_change);
        float program_number = -1.0;
@@ -1249,7 +1381,7 @@ MidiRegionView::get_patch_key_at(double time, uint8_t channel, MIDI::Name::Patch
                program_number = program_control->get_float(true, time);
                cerr << " got program " << program_number << endl;
        }
-       
+
        key.msb = (int) floor(msb + 0.5);
        key.lsb = (int) floor(lsb + 0.5);
        key.program_number = (int) floor(program_number + 0.5);
@@ -1257,7 +1389,7 @@ MidiRegionView::get_patch_key_at(double time, uint8_t channel, MIDI::Name::Patch
 }
 
 
-void 
+void
 MidiRegionView::alter_program_change(PCEvent& old_program, const MIDI::Name::PatchPrimaryKey& new_patch)
 {
        // TODO: Get the real event here and alter them at the original times
@@ -1273,13 +1405,13 @@ MidiRegionView::alter_program_change(PCEvent& old_program, const MIDI::Name::Pat
        if (lsb_control != 0) {
                lsb_control->set_float(float(new_patch.lsb), true, old_program.time);
        }
-       
+
        Evoral::Parameter program_change(MidiPgmChangeAutomation, old_program.channel, 0);
        boost::shared_ptr<Evoral::Control> program_control = _model->control(program_change);
-       
+
        assert(program_control != 0);
        program_control->set_float(float(new_patch.program_number), true, old_program.time);
-       
+
        redisplay_model();
 }
 
@@ -1290,37 +1422,37 @@ MidiRegionView::program_selected(CanvasProgramChange& program, const MIDI::Name:
        alter_program_change(program_change_event, new_patch);
 }
 
-void 
+void
 MidiRegionView::previous_program(CanvasProgramChange& program)
 {
        MIDI::Name::PatchPrimaryKey key;
        get_patch_key_at(program.event_time(), program.channel(), key);
-       
-       boost::shared_ptr<MIDI::Name::Patch> patch = 
+
+       boost::shared_ptr<MIDI::Name::Patch> patch =
                MIDI::Name::MidiPatchManager::instance().previous_patch(
                                _model_name,
-                               _custom_device_mode, 
-                               program.channel(), 
+                               _custom_device_mode,
+                               program.channel(),
                                key);
-       
+
        PCEvent program_change_event(program.event_time(), program.program(), program.channel());
        if (patch) {
                alter_program_change(program_change_event, patch->patch_primary_key());
        }
 }
 
-void 
+void
 MidiRegionView::next_program(CanvasProgramChange& program)
 {
        MIDI::Name::PatchPrimaryKey key;
        get_patch_key_at(program.event_time(), program.channel(), key);
-       
-       boost::shared_ptr<MIDI::Name::Patch> patch = 
+
+       boost::shared_ptr<MIDI::Name::Patch> patch =
                MIDI::Name::MidiPatchManager::instance().next_patch(
                                _model_name,
-                               _custom_device_mode, 
-                               program.channel(), 
-                               key);   
+                               _custom_device_mode,
+                               program.channel(),
+                               key);
 
        PCEvent program_change_event(program.event_time(), program.program(), program.channel());
        if (patch) {
@@ -1365,17 +1497,26 @@ void
 MidiRegionView::unique_select(ArdourCanvas::CanvasNoteEvent* ev)
 {
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
+               if ((*i) != ev) {
 
-               Selection::iterator tmp = i;
-               ++tmp;
+                       Selection::iterator tmp = i;
+                       ++tmp;
 
-               if ((*i) != ev) {
-                       remove_from_selection (*i);
-               } 
+                       (*i)->selected (false);
+                       _selection.erase (i);
 
-               i = tmp;
+                       i = tmp;
+
+               } else {
+                       ++i;
+               }
        }
 
+       /* don't bother with removing this regionview from the editor selection,
+          since we're about to add another note, and thus put/keep this
+          regionview in the editor selection.
+       */
+
        if (!ev->selected()) {
                add_to_selection (ev);
        }
@@ -1403,7 +1544,7 @@ MidiRegionView::note_selected(ArdourCanvas::CanvasNoteEvent* ev, bool add, bool
                for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
                        if ((*i)->note()->end_time() > latest) {
                                latest = (*i)->note()->end_time();
-                       } 
+                       }
                        if ((*i)->note()->time() < earliest) {
                                earliest = (*i)->note()->time();
                        }
@@ -1417,78 +1558,75 @@ MidiRegionView::note_selected(ArdourCanvas::CanvasNoteEvent* ev, bool add, bool
                        earliest = ev->note()->time();
                }
 
+               for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
 
-               for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {           
-                       
                        /* find notes entirely within OR spanning the earliest..latest range */
 
                        if (((*i)->note()->time() >= earliest && (*i)->note()->end_time() <= latest) ||
                            ((*i)->note()->time() <= earliest && (*i)->note()->end_time() >= latest)) {
                                add_to_selection (*i);
-                       }                       
+                       }
+
+#if 0
+                       /* if events were guaranteed to be time sorted, we could do this.
+                          but as of sept 10th 2009, they no longer are.
+                       */
 
                        if ((*i)->note()->time() > latest) {
                                break;
                        }
+#endif
                }
        }
 }
 
-
 void
-MidiRegionView::note_deselected(ArdourCanvas::CanvasNoteEvent* ev, bool add)
+MidiRegionView::note_deselected(ArdourCanvas::CanvasNoteEvent* ev)
 {
-       if (!add) {
-               clear_selection_except(ev);
-       }
-
        remove_from_selection (ev);
 }
 
-
 void
 MidiRegionView::update_drag_selection(double x1, double x2, double y1, double y2)
 {
-       const double last_y = std::min(y1, y2);
-       const double y      = std::max(y1, y2);
+       if (x1 > x2) {
+               swap (x1, x2);
+       }
+
+       if (y1 > y2) {
+               swap (y1, y2);
+       }
 
        // TODO: Make this faster by storing the last updated selection rect, and only
        // adjusting things that are in the area that appears/disappeared.
        // We probably need a tree to be able to find events in O(log(n)) time.
 
-#ifndef NDEBUG
-       double last_x1 = 0.0;
-#endif
+       for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
 
-       if (x1 < x2) {
-               for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
-#ifndef NDEBUG
-                       // Events should always be sorted by increasing x1() here
-                       assert((*i)->x1() >= last_x1);
-                       last_x1 = (*i)->x1();
-#endif
-                       if ((*i)->x1() >= x1 && (*i)->x1() <= x2 && (*i)->y1() >= last_y && (*i)->y1() <= y) {
-                               // Inside rectangle
-                               add_to_selection (*i);
-                       } else if ((*i)->selected()) {
-                               // Not inside rectangle
-                               remove_from_selection (*i);
-                       }
-               }
-       } else {
-               for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
-#ifndef NDEBUG
-                       // Events should always be sorted by increasing x1() here
-                       assert((*i)->x1() >= last_x1);
-                       last_x1 = (*i)->x1();
-#endif
-                       if ((*i)->x2() <= x1 && (*i)->x2() >= x2 && (*i)->y1() >= last_y && (*i)->y1() <= y) {
-                               // Inside rectangle
+               /* check if any corner of the note is inside the rect
+
+                  Notes:
+                    1) this is computing "touched by", not "contained by" the rect.
+                    2) this does not require that events be sorted in time.
+                */
+
+               const double ix1 = (*i)->x1();
+               const double ix2 = (*i)->x2();
+               const double iy1 = (*i)->y1();
+               const double iy2 = (*i)->y2();
+
+               if ((ix1 >= x1 && ix1 <= x2 && iy1 >= y1 && iy1 <= y2) ||
+                   (ix1 >= x1 && ix1 <= x2 && iy2 >= y1 && iy2 <= y2) ||
+                   (ix2 >= x1 && ix2 <= x2 && iy1 >= y1 && iy1 <= y2) ||
+                   (ix2 >= x1 && ix2 <= x2 && iy2 >= y1 && iy2 <= y2)) {
+
+                       // Inside rectangle
+                       if (!(*i)->selected()) {
                                add_to_selection (*i);
-                       } else if ((*i)->selected()) {
-                               // Not inside rectangle
-                               remove_from_selection (*i);
                        }
+               } else if ((*i)->selected()) {
+                       // Not inside rectangle
+                       remove_from_selection (*i);
                }
        }
 }
@@ -1504,7 +1642,7 @@ MidiRegionView::remove_from_selection (CanvasNoteEvent* ev)
 
        ev->selected (false);
        ev->hide_velocity ();
-       
+
        if (_selection.empty()) {
                PublicEditor& editor (trackview.editor());
                editor.get_selection().remove (this);
@@ -1540,81 +1678,63 @@ MidiRegionView::move_selection(double dx, double dy)
 }
 
 void
-MidiRegionView::note_dropped(CanvasNoteEvent* ev, double dt, uint8_t dnote)
+MidiRegionView::note_dropped(CanvasNoteEvent *, double dt, int8_t dnote)
 {
-       // TODO: This would be faster/nicer with a MoveCommand that doesn't need to copy...
-       if (_selection.find(ev) == _selection.end()) {
-               return;
-       }
+       assert (!_selection.empty());
 
-       uint8_t lowest_note_in_selection  = midi_stream_view()->lowest_note();
-       uint8_t highest_note_in_selection = midi_stream_view()->highest_note();
+       uint8_t lowest_note_in_selection  = 127;
+       uint8_t highest_note_in_selection = 0;
        uint8_t highest_note_difference = 0;
 
        // find highest and lowest notes first
+
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
                uint8_t pitch = (*i)->note()->note();
                lowest_note_in_selection  = std::min(lowest_note_in_selection,  pitch);
                highest_note_in_selection = std::max(highest_note_in_selection, pitch);
        }
-       
+
        /*
        cerr << "dnote: " << (int) dnote << endl;
-       cerr << "lowest note (streamview): " << int(midi_stream_view()->lowest_note()) 
+       cerr << "lowest note (streamview): " << int(midi_stream_view()->lowest_note())
             << " highest note (streamview): " << int(midi_stream_view()->highest_note()) << endl;
-       cerr << "lowest note (selection): " << int(lowest_note_in_selection) << " highest note(selection): " 
+       cerr << "lowest note (selection): " << int(lowest_note_in_selection) << " highest note(selection): "
             << int(highest_note_in_selection) << endl;
        cerr << "selection size: " << _selection.size() << endl;
        cerr << "Highest note in selection: " << (int) highest_note_in_selection << endl;
        */
-       
+
        // Make sure the note pitch does not exceed the MIDI standard range
-       if (dnote <= 127 && (highest_note_in_selection + dnote > 127)) {
+       if (highest_note_in_selection + dnote > 127) {
                highest_note_difference = highest_note_in_selection - 127;
        }
-       
-       start_delta_command(_("move notes"));
 
-       for (Selection::iterator i = _selection.begin(); i != _selection.end() ; ) {
-               Selection::iterator next = i;
-               ++next;
+       start_diff_command(_("move notes"));
 
-               const boost::shared_ptr<NoteType> copy(new NoteType(*(*i)->note().get()));
+       for (Selection::iterator i = _selection.begin(); i != _selection.end() ; ++i) {
 
                nframes64_t start_frames = beats_to_frames((*i)->note()->time());
 
-               cerr << "starting at " << (*i)->note()->time() 
-                    << " (" << start_frames << ") delta on drag = " << dt << endl;
-
                if (dt >= 0) {
-                       cerr << "Motion was " << snap_frame_to_frame(trackview.editor().pixel_to_frame(dt)) << endl;
                        start_frames += snap_frame_to_frame(trackview.editor().pixel_to_frame(dt));
                } else {
-                       cerr << "rev Motion was " << snap_frame_to_frame(trackview.editor().pixel_to_frame(dt)) << endl;
                        start_frames -= snap_frame_to_frame(trackview.editor().pixel_to_frame(-dt));
                }
 
-               cerr << "start frame will be " << start_frames << " vs. region " 
-                    << _region->position ()
-                    << endl;
-
                Evoral::MusicalTime new_time = frames_to_beats(start_frames);
 
                if (new_time < 0) {
-                       i = next;
                        continue;
                }
 
-               copy->set_time (new_time);
-
-               cerr << "copy time = " << copy->time() << endl;
+               diff_add_change (*i, MidiModel::DiffCommand::StartTime, new_time);
 
                uint8_t original_pitch = (*i)->note()->note();
                uint8_t new_pitch      = original_pitch + dnote - highest_note_difference;
-               
+
                // keep notes in standard midi range
                clamp_to_0_127(new_pitch);
-               
+
                // keep original pitch if note is dragged outside valid midi range
                if ((original_pitch != 0 && new_pitch == 0)
                                || (original_pitch != 127 && new_pitch == 127)) {
@@ -1624,20 +1744,14 @@ MidiRegionView::note_dropped(CanvasNoteEvent* ev, double dt, uint8_t dnote)
                lowest_note_in_selection  = std::min(lowest_note_in_selection,  new_pitch);
                highest_note_in_selection = std::max(highest_note_in_selection, new_pitch);
 
-               copy->set_note(new_pitch);
-               
-               delta_remove_note(*i);
-               cerr << "Adding note: " << *copy << endl;
-               delta_add_note(copy, (*i)->selected());
-
-               i = next;
+               diff_add_change (*i, MidiModel::DiffCommand::NoteNumber, new_pitch);
        }
 
-       apply_delta();
-       
+       apply_diff();
+
        // care about notes being moved beyond the upper/lower bounds on the canvas
        if (lowest_note_in_selection  < midi_stream_view()->lowest_note() ||
-                       highest_note_in_selection > midi_stream_view()->highest_note()) {
+           highest_note_in_selection > midi_stream_view()->highest_note()) {
                midi_stream_view()->set_note_range(MidiStreamView::ContentsRange);
        }
 }
@@ -1675,6 +1789,13 @@ MidiRegionView::get_position_pixels()
        return trackview.editor().frame_to_pixel(region_frame);
 }
 
+double
+MidiRegionView::get_end_position_pixels()
+{
+       nframes64_t frame = get_position() + get_duration ();
+       return trackview.editor().frame_to_pixel(frame);
+}
+
 nframes64_t
 MidiRegionView::beats_to_frames(double beats) const
 {
@@ -1688,7 +1809,7 @@ MidiRegionView::frames_to_beats(nframes64_t frames) const
 }
 
 void
-MidiRegionView::begin_resizing(CanvasNote::NoteEnd note_end)
+MidiRegionView::begin_resizing (bool /*at_front*/)
 {
        _resize_data.clear();
 
@@ -1722,37 +1843,36 @@ MidiRegionView::begin_resizing(CanvasNote::NoteEnd note_end)
                                        ARDOUR_UI::config()->canvasvar_MidiNoteSelected.get());
 
                        resize_data->resize_rect = resize_rect;
-
-                       if (note_end == CanvasNote::NOTE_ON) {
-                               resize_data->current_x = note->x1();
-                       } else { // NOTE_OFF
-                               resize_data->current_x = note->x2();
-                       }
-
                        _resize_data.push_back(resize_data);
                }
        }
 }
 
 void
-MidiRegionView::update_resizing(CanvasNote::NoteEnd note_end, double x, bool relative)
+MidiRegionView::update_resizing (bool at_front, double delta_x, bool relative)
 {
        for (std::vector<NoteResizeData *>::iterator i = _resize_data.begin(); i != _resize_data.end(); ++i) {
                SimpleRect* resize_rect = (*i)->resize_rect;
                CanvasNote* canvas_note = (*i)->canvas_note;
+               double current_x;
 
-               const double region_start = get_position_pixels();
-
-               if (relative) {
-                       (*i)->current_x = (*i)->current_x + x;
+               if (at_front) {
+                       if (relative) {
+                               current_x = canvas_note->x1() + delta_x;
+                       } else {
+                               // x is in track relative, transform it to region relative
+                               current_x = delta_x - get_position_pixels();
+                       }
                } else {
-                       // x is in track relative, transform it to region relative
-                       (*i)->current_x = x - region_start;
+                       if (relative) {
+                               current_x = canvas_note->x2() + delta_x;
+                       } else {
+                               // x is in track relative, transform it to region relative
+                               current_x = delta_x - get_end_position_pixels ();
+                       }
                }
 
-               double current_x = (*i)->current_x;
-
-               if (note_end == CanvasNote::NOTE_ON) {
+               if (at_front) {
                        resize_rect->property_x1() = snap_to_pixel(current_x);
                        resize_rect->property_x2() = canvas_note->x2();
                } else {
@@ -1763,40 +1883,54 @@ MidiRegionView::update_resizing(CanvasNote::NoteEnd note_end, double x, bool rel
 }
 
 void
-MidiRegionView::commit_resizing(CanvasNote::NoteEnd note_end, double event_x, bool relative)
+MidiRegionView::commit_resizing (bool at_front, double delta_x, bool relative)
 {
-       start_delta_command(_("resize notes"));
+       start_diff_command(_("resize notes"));
 
        for (std::vector<NoteResizeData *>::iterator i = _resize_data.begin(); i != _resize_data.end(); ++i) {
                CanvasNote*  canvas_note = (*i)->canvas_note;
                SimpleRect*  resize_rect = (*i)->resize_rect;
-               double       current_x   = (*i)->current_x;
-               const double position    = get_position_pixels();
+               const double region_start = get_position_pixels();
+               double current_x;
 
-               if (!relative) {
-                       // event_x is in track relative, transform it to region relative
-                       current_x = event_x - position;
+               if (at_front) {
+                       if (relative) {
+                               current_x = canvas_note->x1() + delta_x;
+                       } else {
+                               // x is in track relative, transform it to region relative
+                               current_x = region_start + delta_x;
+                       }
+               } else {
+                       if (relative) {
+                               current_x = canvas_note->x2() + delta_x;
+                       } else {
+                               // x is in track relative, transform it to region relative
+                               current_x = region_start + delta_x;
+                       }
                }
 
-               // because snapping works on world coordinates we have to transform current_x
-               // to world coordinates before snapping and transform it back afterwards
-               nframes64_t current_frame = snap_pixel_to_frame(current_x);
-               // transform to region start relative
-               current_frame += _region->start();
-               
-               const boost::shared_ptr<NoteType> copy(new NoteType(*(canvas_note->note().get())));
-
-               // resize beginning of note
-               if (note_end == CanvasNote::NOTE_ON && current_frame < copy->end_time()) {
-                       delta_remove_note(canvas_note);
-                       copy->on_event().time() = current_frame;
-                       delta_add_note(copy, _selection.find(canvas_note) != _selection.end());
+               current_x = snap_pixel_to_frame (current_x);
+               current_x = frames_to_beats (current_x);
+
+               if (at_front && current_x < canvas_note->note()->end_time()) {
+                       diff_add_change (canvas_note, MidiModel::DiffCommand::StartTime, current_x);
+
+                       double len = canvas_note->note()->time() - current_x;
+                       len += canvas_note->note()->length();
+
+                       if (len > 0) {
+                               /* XXX convert to beats */
+                               diff_add_change (canvas_note, MidiModel::DiffCommand::Length, len);
+                       }
                }
-               // resize end of note
-               if (note_end == CanvasNote::NOTE_OFF && current_frame > copy->time()) {
-                       delta_remove_note(canvas_note);
-                       copy->off_event().time() = current_frame;
-                       delta_add_note(copy, _selection.find(canvas_note) != _selection.end());
+
+               if (!at_front) {
+                       double len = current_x - canvas_note->note()->time();
+
+                       if (len > 0) {
+                               /* XXX convert to beats */
+                               diff_add_change (canvas_note, MidiModel::DiffCommand::Length, len);
+                       }
                }
 
                delete resize_rect;
@@ -1804,24 +1938,22 @@ MidiRegionView::commit_resizing(CanvasNote::NoteEnd note_end, double event_x, bo
        }
 
        _resize_data.clear();
-       apply_delta();
+       apply_diff();
 }
 
 void
 MidiRegionView::change_note_velocity(CanvasNoteEvent* event, int8_t velocity, bool relative)
 {
-       const boost::shared_ptr<NoteType> copy(new NoteType(*(event->note().get())));
+       uint8_t new_velocity;
 
        if (relative) {
-               uint8_t new_velocity = copy->velocity() + velocity;
+               new_velocity = event->note()->velocity() + velocity;
                clamp_to_0_127(new_velocity);
-               copy->set_velocity(new_velocity);
        } else {
-               copy->set_velocity(velocity);                   
+               new_velocity = velocity;
        }
 
-       delta_remove_note(event);
-       delta_add_note(copy, event->selected(), true);
+       diff_add_change (event, MidiModel::DiffCommand::Velocity, new_velocity);
 }
 
 void
@@ -1856,8 +1988,6 @@ MidiRegionView::trim_note (CanvasNoteEvent* event, Evoral::MusicalTime front_del
                        if negative - move the end of the note earlier in time (shortening it)
         */
 
-       cerr << "Trim front by " << front_delta << " end by " << end_delta << endl;
-
        if (front_delta) {
                if (front_delta < 0) {
 
@@ -1878,11 +2008,11 @@ MidiRegionView::trim_note (CanvasNoteEvent* event, Evoral::MusicalTime front_del
                } else {
 
                        Evoral::MusicalTime new_pos = event->note()->time() + front_delta;
-                       
+
                        if (new_pos < event->note()->end_time()) {
                                new_start = event->note()->time() + front_delta;
                                /* start moved toward the end, so move the end point back to where it used to be */
-                               new_length = event->note()->length() - front_delta; 
+                               new_length = event->note()->length() - front_delta;
                                change_start = true;
                                change_length = true;
                        }
@@ -1896,7 +2026,7 @@ MidiRegionView::trim_note (CanvasNoteEvent* event, Evoral::MusicalTime front_del
                        if (event->note()->length() < -end_delta) {
                                can_change = false;
                        }
-               } 
+               }
 
                if (can_change) {
                        new_length = event->note()->length() + end_delta;
@@ -1916,24 +2046,23 @@ MidiRegionView::trim_note (CanvasNoteEvent* event, Evoral::MusicalTime front_del
 void
 MidiRegionView::change_note_time (CanvasNoteEvent* event, Evoral::MusicalTime delta, bool relative)
 {
-       const boost::shared_ptr<NoteType> copy(new NoteType(*(event->note().get())));
+       Evoral::MusicalTime new_time;
 
        if (relative) {
                if (delta < 0.0) {
-                       if (copy->time() < -delta) {
-                               copy->set_time (0);
+                       if (event->note()->time() < -delta) {
+                               new_time = 0;
                        } else {
-                               copy->set_time (copy->time() + delta);
-                       } 
+                               new_time = event->note()->time() + delta;
+                       }
                } else {
-                       copy->set_time (copy->time() + delta);
+                       new_time = event->note()->time() + delta;
                }
        } else {
-               copy->set_time (delta);
+               new_time = delta;
        }
 
-       delta_remove_note(event);
-       delta_add_note(copy, event->selected(), false);
+       diff_add_change (event, MidiModel::DiffCommand::StartTime, new_time);
 }
 
 void
@@ -1963,16 +2092,16 @@ MidiRegionView::change_velocities (bool up, bool fine, bool allow_smush)
                }
        }
 
-       start_delta_command(_("change velocities"));
-       
+       start_diff_command(_("change velocities"));
+
        for (Selection::iterator i = _selection.begin(); i != _selection.end();) {
                Selection::iterator next = i;
                ++next;
                change_note_velocity (*i, delta, true);
                i = next;
        }
-       
-       apply_delta();
+
+       apply_diff();
 }
 
 
@@ -1984,7 +2113,7 @@ MidiRegionView::transpose (bool up, bool fine, bool allow_smush)
        }
 
        int8_t delta;
-       
+
        if (fine) {
                delta = 1;
        } else {
@@ -2042,13 +2171,13 @@ MidiRegionView::change_note_lengths (bool fine, bool shorter, bool start, bool e
        if (shorter) {
                delta = -delta;
        }
-       
+
        start_diff_command (_("change note lengths"));
 
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
                Selection::iterator next = i;
                ++next;
-               
+
                /* note the negation of the delta for start */
 
                trim_note (*i, (start ? -delta : 0), (end ? delta : 0));
@@ -2066,8 +2195,8 @@ MidiRegionView::nudge_notes (bool forward)
                return;
        }
 
-       /* pick a note as the point along the timeline to get the nudge distance. 
-          its not necessarily the earliest note, so we may want to pull the notes out 
+       /* pick a note as the point along the timeline to get the nudge distance.
+          its not necessarily the earliest note, so we may want to pull the notes out
           into a vector and sort before using the first one.
        */
 
@@ -2080,23 +2209,23 @@ MidiRegionView::nudge_notes (bool forward)
                /* no nudge distance set - use grid */
 
                nframes64_t next_pos = ref_point;
-               
+
                if (forward) {
                        /* XXX need check on max_frames, but that needs max_frames64 or something */
                        next_pos += 1;
-               } else { 
+               } else {
                        if (next_pos == 0) {
                                return;
                        }
                        next_pos -= 1;
                }
-               
+
                cerr << "ref point was " << ref_point << " next was " << next_pos;
                trackview.editor().snap_to (next_pos, (forward ? 1 : -1), false);
                distance = ref_point - next_pos;
                cerr << " final is " << next_pos << " distance = " << distance << endl;
-       } 
-               
+       }
+
        if (distance == 0) {
                return;
        }
@@ -2107,7 +2236,7 @@ MidiRegionView::nudge_notes (bool forward)
                delta = -delta;
        }
 
-       start_delta_command (_("nudge"));
+       start_diff_command (_("nudge"));
 
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
                Selection::iterator next = i;
@@ -2116,30 +2245,17 @@ MidiRegionView::nudge_notes (bool forward)
                i = next;
        }
 
-       apply_delta ();
+       apply_diff ();
 }
 
-
 void
 MidiRegionView::change_channel(uint8_t channel)
 {
-       start_delta_command(_("change channel"));
-       for (Selection::iterator i = _selection.begin(); i != _selection.end();) {
-               Selection::iterator next = i;
-               ++next;
-
-               CanvasNoteEvent* event = *i;
-               const boost::shared_ptr<NoteType> copy(new NoteType(*(event->note().get())));
-
-               copy->set_channel(channel);
-               
-               delta_remove_note(event);
-               delta_add_note(copy, event->selected());
-               
-               i = next;
+       start_diff_command(_("change channel"));
+       for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
+               diff_add_change (*i, MidiModel::DiffCommand::Channel, channel);
        }
-       
-       apply_delta();
+       apply_diff();
 }
 
 
@@ -2151,16 +2267,19 @@ MidiRegionView::note_entered(ArdourCanvas::CanvasNoteEvent* ev)
        }
 
        PublicEditor& editor (trackview.editor());
-       editor.show_verbose_canvas_cursor_with (Evoral::midi_note_name (ev->note()->note()));
+       char buf[4];
+       snprintf (buf, sizeof (buf), "%d", (int) ev->note()->note());
+       //editor.show_verbose_canvas_cursor_with (Evoral::midi_note_name (ev->note()->note()));
+       editor.show_verbose_canvas_cursor_with (buf);
 }
 
 void
-MidiRegionView::note_left (ArdourCanvas::CanvasNoteEvent* ev)
+MidiRegionView::note_left (ArdourCanvas::CanvasNoteEvent*)
 {
        PublicEditor& editor (trackview.editor());
        editor.hide_verbose_canvas_cursor ();
 }
-       
+
 
 void
 MidiRegionView::switch_source(boost::shared_ptr<Source> src)
@@ -2182,7 +2301,7 @@ MidiRegionView::set_frame_color()
        }
 }
 
-void 
+void
 MidiRegionView::midi_channel_mode_changed(ChannelMode mode, uint16_t mask)
 {
        switch (mode) {
@@ -2203,7 +2322,7 @@ MidiRegionView::midi_channel_mode_changed(ChannelMode mode, uint16_t mask)
        _last_channel_selection = mask;
 }
 
-void 
+void
 MidiRegionView::midi_patch_settings_changed(std::string model, std::string custom_device_mode)
 {
        _model_name         = model;
@@ -2228,7 +2347,7 @@ MidiRegionView::cut_copy_clear (Editing::CutCopyOp op)
        default:
                break;
        }
-               
+
        start_delta_command();
 
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
@@ -2249,20 +2368,15 @@ MidiRegionView::cut_copy_clear (Editing::CutCopyOp op)
 MidiCutBuffer*
 MidiRegionView::selection_as_cut_buffer () const
 {
-       NoteList notes;
+       Notes notes;
 
        for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
-               notes.push_back (boost::shared_ptr<NoteType> (new NoteType (*((*i)->note().get()))));
+               notes.insert (boost::shared_ptr<NoteType> (new NoteType (*((*i)->note().get()))));
        }
 
-       /* sort them into time order */
-
-       Evoral::Sequence<Evoral::MusicalTime>::LaterNoteComparator cmp;
-       sort (notes.begin(), notes.end(),  cmp);
-
        MidiCutBuffer* cb = new MidiCutBuffer (trackview.session());
        cb->set (notes);
-       
+
        return cb;
 }
 
@@ -2280,17 +2394,17 @@ MidiRegionView::paste (nframes64_t pos, float times, const MidiCutBuffer& mcb)
        Evoral::MusicalTime duration;
        Evoral::MusicalTime end_point;
 
-       duration = mcb.notes().back()->end_time() - mcb.notes().front()->time();
+       duration = (*mcb.notes().rbegin())->end_time() - (*mcb.notes().begin())->time();
        paste_pos_beats = frames_to_beats (pos - _region->position());
-       beat_delta = mcb.notes().front()->time() - paste_pos_beats;
+       beat_delta = (*mcb.notes().begin())->time() - paste_pos_beats;
        paste_pos_beats = 0;
 
        _selection.clear ();
 
        for (int n = 0; n < (int) times; ++n) {
 
-               for (NoteList::const_iterator i = mcb.notes().begin(); i != mcb.notes().end(); ++i) {
-                       
+               for (Notes::const_iterator i = mcb.notes().begin(); i != mcb.notes().end(); ++i) {
+
                        boost::shared_ptr<NoteType> copied_note (new NoteType (*((*i).get())));
                        copied_note->set_time (paste_pos_beats + copied_note->time() - beat_delta);
 
@@ -2316,30 +2430,27 @@ MidiRegionView::paste (nframes64_t pos, float times, const MidiCutBuffer& mcb)
                _region->set_length (end_frame, this);
                trackview.session().add_command (new MementoCommand<Region>(*_region, &before, &_region->get_state()));
        }
-       
+
        apply_delta ();
 }
 
+struct EventNoteTimeEarlyFirstComparator {
+    bool operator() (CanvasNoteEvent* a, CanvasNoteEvent* b) {
+           return a->note()->time() < b->note()->time();
+    }
+};
+
 void
-MidiRegionView::add_note (uint8_t channel, uint8_t number, uint8_t velocity, 
-                         Evoral::MusicalTime pos, Evoral::MusicalTime len)
+MidiRegionView::time_sort_events ()
 {
-       boost::shared_ptr<NoteType> new_note (new NoteType (channel, pos, len, number, velocity));
-       
-       start_delta_command (_("step add"));
-       delta_add_note (new_note, true, false);
-       apply_delta();
-
-       /* potentially extend region to hold new note */
+       if (!_sort_needed) {
+               return;
+       }
 
-       nframes64_t end_frame = _region->position() + beats_to_frames (new_note->end_time());
-       nframes64_t region_end = _region->position() + _region->length() - 1;
+       EventNoteTimeEarlyFirstComparator cmp;
+       _events.sort (cmp);
 
-       if (end_frame > region_end) {
-               _region->set_length (end_frame, this);
-       } else {
-               redisplay_model ();
-       }
+       _sort_needed = false;
 }
 
 void
@@ -2352,6 +2463,8 @@ MidiRegionView::goto_next_note ()
                return;
        }
 
+       time_sort_events ();
+
        for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
                if ((*i)->selected()) {
                        use_next = true;
@@ -2366,7 +2479,7 @@ MidiRegionView::goto_next_note ()
        /* use the first one */
 
        unique_select (_events.front());
-       
+
 }
 
 void
@@ -2379,6 +2492,8 @@ MidiRegionView::goto_previous_note ()
                return;
        }
 
+       time_sort_events ();
+
        for (Events::reverse_iterator i = _events.rbegin(); i != _events.rend(); ++i) {
                if ((*i)->selected()) {
                        use_next = true;
@@ -2396,39 +2511,15 @@ MidiRegionView::goto_previous_note ()
 }
 
 void
-MidiRegionView::selection_as_notelist (NoteList& selected) 
+MidiRegionView::selection_as_notelist (Notes& selected)
 {
+       time_sort_events ();
+
        for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
                if ((*i)->selected()) {
-                       /* make a copy of the original */
-                       selected.push_back (boost::shared_ptr<Evoral::Note<Evoral::MusicalTime> >
-                                           (new Evoral::Note<Evoral::MusicalTime> (*((*i)->note()))));
+                       selected.insert ((*i)->note());
                }
        }
 }
 
-void
-MidiRegionView::replace_selected (NoteList& replacements)
-{
-       start_delta_command ("whatever");
-
-       for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
-               Selection::iterator tmp;
-               tmp = i;
-               ++tmp;
-
-               delta_remove_note (*i);
-               remove_from_selection (*i);
-
-               i = tmp;
-       }
-
-       _selection.clear ();
-
-       for (NoteList::iterator i = replacements.begin(); i != replacements.end(); ++i) {
-               delta_add_note (*i, true, false);
-       }
-       
-       apply_delta_as_subcommand ();
-}