split out the logic behind step editing from MidiTimeAxisView as much as possible

git-svn-id: svn://localhost/ardour2/branches/3.0@7633 d708f5d6-7413-0410-9779-e7cbd77b26cf

7 files changed, 555 insertions, 439 deletions

diff --git a/gtk2_ardour/midi_time_axis.cc b/gtk2_ardour/midi_time_axis.cc
index 3eb7fff692..62beda8774 100644
--- a/gtk2_ardour/midi_time_axis.cc
+++ b/gtk2_ardour/midi_time_axis.cc
@@ -80,8 +80,8 @@
 #include "region_view.h"
 #include "rgb_macros.h"
 #include "selection.h"
+#include "step_editor.h"
 #include "simplerect.h"
-#include "step_entry.h"
 #include "utils.h"
 
 #include "ardour/midi_track.h"
@@ -116,7 +116,6 @@ MidiTimeAxisView::MidiTimeAxisView (PublicEditor& ed, Session* sess,
 	, _midi_thru_item (0)
 	, default_channel_menu (0)
 	, controller_menu (0)
-        , step_editor (0)
 {
 	subplugin_menu.set_name ("ArdourContextMenu");
 
@@ -127,8 +126,6 @@ MidiTimeAxisView::MidiTimeAxisView (PublicEditor& ed, Session* sess,
 	mute_button->set_active (false);
 	solo_button->set_active (false);
 
-	step_edit_insert_position = 0;
-
 	if (is_midi_track()) {
 		controls_ebox.set_name ("MidiTimeAxisViewControlsBaseUnselected");
 		_note_mode = midi_track()->note_mode();
@@ -168,11 +165,6 @@ MidiTimeAxisView::MidiTimeAxisView (PublicEditor& ed, Session* sess,
 		_view->RegionViewAdded.connect (sigc::mem_fun(*this, &MidiTimeAxisView::region_view_added));
 		_view->attach ();
                 
-                midi_track()->PlaylistChanged.connect (*this, invalidator (*this),
-                                                       boost::bind (&MidiTimeAxisView::playlist_changed, this),
-                                                       gui_context());
-                playlist_changed ();
-
 	}
 
 	HBox* midi_controls_hbox = manage(new HBox());
@@ -235,35 +227,17 @@ MidiTimeAxisView::~MidiTimeAxisView ()
 	_range_scroomer = 0;
 
 	delete controller_menu;
+        delete _step_editor;
 }
 
 void
-MidiTimeAxisView::playlist_changed ()
+MidiTimeAxisView::check_step_edit ()
 {
-        step_edit_region_connection.disconnect ();
-        midi_track()->playlist()->RegionRemoved.connect (step_edit_region_connection, invalidator (*this),
-                                                         ui_bind (&MidiTimeAxisView::region_removed, this, _1),
-                                                         gui_context());
+        _step_editor->check_step_edit ();
 }
 
-void
-MidiTimeAxisView::region_removed (boost::weak_ptr<Region> wr)
-{
-        boost::shared_ptr<Region> r (wr.lock());
- 
-        if (!r) {
-                return;
-        }
-
-        if (step_edit_region == r) {
-                step_edit_region.reset();
-                step_edit_region_view = 0;
-                // force a recompute of the insert position
-                step_edit_beat_pos = -1.0;
-        }
-}
-
-void MidiTimeAxisView::model_changed()
+void 
+MidiTimeAxisView::model_changed()
 {
 	std::list<std::string> device_modes = MIDI::Name::MidiPatchManager::instance()
 		.custom_device_mode_names_by_model(_model_selector.get_active_text());
@@ -892,360 +866,7 @@ MidiTimeAxisView::route_active_changed ()
 	}
 }
 
-void
-MidiTimeAxisView::start_step_editing ()
-{
-        _step_edit_triplet_countdown = 0;
-        _step_edit_within_chord = 0;
-        _step_edit_chord_duration = 0.0;
-        step_edit_region.reset ();
-        step_edit_region_view = 0;
-
-        resync_step_edit_position ();
-        prepare_step_edit_region ();
-        reset_step_edit_beat_pos ();
-
-        assert (step_edit_region);
-        assert (step_edit_region_view);
-
-        if (step_editor == 0) {
-                step_editor = new StepEntry (*this);
-                step_editor->signal_delete_event().connect (sigc::mem_fun (*this, &MidiTimeAxisView::step_editor_hidden));
-                step_editor->signal_hide().connect (sigc::mem_fun (*this, &MidiTimeAxisView::step_editor_hide));
-        }
-
-        step_edit_region_view->show_step_edit_cursor (step_edit_beat_pos);
-        step_edit_region_view->set_step_edit_cursor_width (step_editor->note_length());
-
-        step_editor->set_position (WIN_POS_MOUSE);
-        step_editor->present ();
-}
-
-void
-MidiTimeAxisView::resync_step_edit_position ()
-{
-	step_edit_insert_position = _editor.get_preferred_edit_position ();
-}
-
-void
-MidiTimeAxisView::resync_step_edit_to_edit_point ()
-{
-        resync_step_edit_position ();
-        if (step_edit_region) {
-                reset_step_edit_beat_pos ();
-        }
-}
-
-void
-MidiTimeAxisView::prepare_step_edit_region ()
-{
-        boost::shared_ptr<Region> r = playlist()->top_region_at (step_edit_insert_position);
-
-        if (r) {
-                step_edit_region = boost::dynamic_pointer_cast<MidiRegion>(r);
-        }
-
-	if (step_edit_region) {
-		RegionView* rv = view()->find_view (step_edit_region);
-		step_edit_region_view = dynamic_cast<MidiRegionView*> (rv);
-
-	} else {
-                step_edit_region = add_region (step_edit_insert_position);
-                RegionView* rv = view()->find_view (step_edit_region);
-                step_edit_region_view = dynamic_cast<MidiRegionView*>(rv);
-        }
-}
-
-
-void
-MidiTimeAxisView::reset_step_edit_beat_pos ()
-{
-        assert (step_edit_region);
-        assert (step_edit_region_view);
-
-        framecnt_t frames_from_start = _editor.get_preferred_edit_position() - step_edit_region->position();
-        
-        if (frames_from_start < 0) {
-                /* this can happen with snap enabled, and the edit point == Playhead. we snap the
-                   position of the new region, and it can end up after the edit point.
-                */
-                frames_from_start = 0;
-        }
-        
-        step_edit_beat_pos = step_edit_region_view->frames_to_beats (frames_from_start);
-        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-}
-
-bool
-MidiTimeAxisView::step_editor_hidden (GdkEventAny*)
-{
-        step_editor_hide ();
-        return true;
-}
-
-void
-MidiTimeAxisView::step_editor_hide ()
-{
-        /* everything else will follow the change in the model */
-	midi_track()->set_step_editing (false);
-}
-
-void
-MidiTimeAxisView::stop_step_editing ()
-{
-        if (step_editor) {
-                step_editor->hide ();
-        }
-
-        if (step_edit_region_view) {
-                step_edit_region_view->hide_step_edit_cursor();
-        }
-
-        step_edit_region.reset ();
-}
-
-void
-MidiTimeAxisView::check_step_edit ()
-{
-	MidiRingBuffer<nframes_t>& incoming (midi_track()->step_edit_ring_buffer());
-	uint8_t* buf;
-	uint32_t bufsize = 32;
-
-	buf = new uint8_t[bufsize];
-
-	while (incoming.read_space()) {
-		nframes_t time;
-		Evoral::EventType type;
-		uint32_t size;
-
-		incoming.read_prefix (&time, &type, &size);
-
-		if (size > bufsize) {
-			delete [] buf;
-			bufsize = size;
-			buf = new uint8_t[bufsize];
-		}
-
-		incoming.read_contents (size, buf);
-
-		if ((buf[0] & 0xf0) == MIDI_CMD_NOTE_ON) {
-                        step_add_note (buf[0] & 0xf, buf[1], buf[2], 0.0);
-		}
-	}
-}
-
-int
-MidiTimeAxisView::step_add_bank_change (uint8_t channel, uint8_t bank)
-{
-        return 0;
-}
-
-int
-MidiTimeAxisView::step_add_program_change (uint8_t channel, uint8_t program)
-{
-        return 0;
-}
-
-void
-MidiTimeAxisView::step_edit_sustain (Evoral::MusicalTime beats)
-{
-        if (step_edit_region_view) {
-                step_edit_region_view->step_sustain (beats);
-        }
-}
-
-void
-MidiTimeAxisView::move_step_edit_beat_pos (Evoral::MusicalTime beats)
-{
-        if (beats > 0.0) {
-                step_edit_beat_pos = min (step_edit_beat_pos + beats, 
-                                          step_edit_region_view->frames_to_beats (step_edit_region->length()));
-        } else if (beats < 0.0) {
-                if (beats < step_edit_beat_pos) {
-                        step_edit_beat_pos += beats; // its negative, remember
-                } else {
-                        step_edit_beat_pos = 0;
-                }
-        }
-        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-}
-
-int
-MidiTimeAxisView::step_add_note (uint8_t channel, uint8_t pitch, uint8_t velocity, Evoral::MusicalTime beat_duration)
-{
-        /* do these things in case undo removed the step edit region
-        */
-        if (!step_edit_region) {
-                resync_step_edit_position ();
-                prepare_step_edit_region ();
-                reset_step_edit_beat_pos ();
-                step_edit_region_view->show_step_edit_cursor (step_edit_beat_pos);
-                step_edit_region_view->set_step_edit_cursor_width (step_editor->note_length());
-        }
-
-        assert (step_edit_region);
-        assert (step_edit_region_view);
-                
-        if (beat_duration == 0.0) {
-                bool success;
-                beat_duration = _editor.get_grid_type_as_beats (success, step_edit_insert_position);
-                
-                if (!success) {
-                        return -1;
-                }
-        }
-        
-        MidiStreamView* msv = midi_view();
-        
-        /* make sure its visible on the vertical axis */
-        
-        if (pitch < msv->lowest_note() || pitch > msv->highest_note()) {
-                msv->update_note_range (pitch);
-                msv->set_note_range (MidiStreamView::ContentsRange);
-        }
-        
-        /* make sure its visible on the horizontal axis */
-        
-        nframes64_t fpos = step_edit_region->position() + 
-                step_edit_region_view->beats_to_frames (step_edit_beat_pos + beat_duration);
-        
-        if (fpos >= (_editor.leftmost_position() + _editor.current_page_frames())) {
-                _editor.reset_x_origin (fpos - (_editor.current_page_frames()/4));
-        }
-        
-        step_edit_region_view->step_add_note (channel, pitch, velocity, step_edit_beat_pos, beat_duration);
-        
-        if (_step_edit_triplet_countdown > 0) {
-                _step_edit_triplet_countdown--;
-                
-                if (_step_edit_triplet_countdown == 0) {
-                        _step_edit_triplet_countdown = 3;
-                }
-        }
-        
-        if (!_step_edit_within_chord) {
-                step_edit_beat_pos += beat_duration;
-                step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-        } else {
-                step_edit_beat_pos += 1.0/Meter::ticks_per_beat; // tiny, but no longer overlapping
-                _step_edit_chord_duration = max (_step_edit_chord_duration, beat_duration);
-        }
-
-        return 0;
-}
-
-void
-MidiTimeAxisView::set_step_edit_cursor_width (Evoral::MusicalTime beats)
-{
-        if (step_edit_region_view) {
-                step_edit_region_view->set_step_edit_cursor_width (beats);
-        }
-}
-
-bool
-MidiTimeAxisView::step_edit_within_triplet() const
-{
-        return _step_edit_triplet_countdown > 0;
-}
-
-bool
-MidiTimeAxisView::step_edit_within_chord() const
-{
-        return _step_edit_within_chord;
-}
-
-void
-MidiTimeAxisView::step_edit_toggle_triplet ()
-{
-        if (_step_edit_triplet_countdown == 0) {
-                _step_edit_within_chord = false;
-                _step_edit_triplet_countdown = 3;
-        } else {
-                _step_edit_triplet_countdown = 0;
-        }
-}
-
-void
-MidiTimeAxisView::step_edit_toggle_chord ()
-{
-        if (_step_edit_within_chord) {
-                _step_edit_within_chord = false;
-                step_edit_beat_pos += _step_edit_chord_duration;
-                step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-        } else {
-                _step_edit_triplet_countdown = 0;
-                _step_edit_within_chord = true;
-        }
-}
-
-void
-MidiTimeAxisView::step_edit_rest (Evoral::MusicalTime beats)
-{
-	bool success;
-
-        if (beats == 0.0) {
-                beats = _editor.get_grid_type_as_beats (success, step_edit_insert_position);
-        } else {
-                success = true;
-        }
-
-        if (success) {
-                step_edit_beat_pos += beats;
-                step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-        }
-}
-
-void 
-MidiTimeAxisView::step_edit_beat_sync ()
-{
-        step_edit_beat_pos = ceil (step_edit_beat_pos);
-        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-}
-
-void 
-MidiTimeAxisView::step_edit_bar_sync ()
-{
-        if (!_session || !step_edit_region_view || !step_edit_region) {
-                return;
-        }
-
-        framepos_t fpos = step_edit_region->position() + 
-                step_edit_region_view->beats_to_frames (step_edit_beat_pos);
-        fpos = _session->tempo_map().round_to_bar (fpos, 1);
-        step_edit_beat_pos = ceil (step_edit_region_view->frames_to_beats (fpos - step_edit_region->position()));
-        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
-}
-
-boost::shared_ptr<MidiRegion>
-MidiTimeAxisView::add_region (framepos_t pos)
-{
-	Editor* real_editor = dynamic_cast<Editor*> (&_editor);
-
-	real_editor->begin_reversible_command (_("create region"));
-        playlist()->clear_history ();
-
-	real_editor->snap_to (pos, 0);
-	const Meter& m = _session->tempo_map().meter_at(pos);
-	const Tempo& t = _session->tempo_map().tempo_at(pos);
-	double length = floor (m.frames_per_bar(t, _session->frame_rate()));
-
-	boost::shared_ptr<Source> src = _session->create_midi_source_for_session (view()->trackview().track().get(),
-                                                                                  view()->trackview().track()->name());
-	PropertyList plist; 
-	
-	plist.add (ARDOUR::Properties::start, 0);
-	plist.add (ARDOUR::Properties::length, length);
-	plist.add (ARDOUR::Properties::name, PBD::basename_nosuffix(src->name()));
-	
-	boost::shared_ptr<Region> region = (RegionFactory::create (src, plist));
-        
-	playlist()->add_region (region, pos);
-	_session->add_command (new StatefulDiffCommand (playlist()));
-
-	real_editor->commit_reversible_command();
 
-	return boost::dynamic_pointer_cast<MidiRegion>(region);
-}
 
 void
 MidiTimeAxisView::add_note_selection (uint8_t note)
@@ -1380,3 +1001,52 @@ MidiTimeAxisView::automation_child_menu_item (Evoral::Parameter param)
 
 	return 0;
 }
+
+boost::shared_ptr<MidiRegion>
+MidiTimeAxisView::add_region (framepos_t pos)
+{
+	Editor* real_editor = dynamic_cast<Editor*> (&_editor);
+
+	real_editor->begin_reversible_command (_("create region"));
+        playlist()->clear_history ();
+
+	real_editor->snap_to (pos, 0);
+	const Meter& m = _session->tempo_map().meter_at(pos);
+	const Tempo& t = _session->tempo_map().tempo_at(pos);
+	double length = floor (m.frames_per_bar(t, _session->frame_rate()));
+
+	boost::shared_ptr<Source> src = _session->create_midi_source_for_session (view()->trackview().track().get(),
+                                                                                  view()->trackview().track()->name());
+	PropertyList plist; 
+	
+	plist.add (ARDOUR::Properties::start, 0);
+	plist.add (ARDOUR::Properties::length, length);
+	plist.add (ARDOUR::Properties::name, PBD::basename_nosuffix(src->name()));
+	
+	boost::shared_ptr<Region> region = (RegionFactory::create (src, plist));
+        
+	playlist()->add_region (region, pos);
+	_session->add_command (new StatefulDiffCommand (playlist()));
+
+	real_editor->commit_reversible_command();
+
+	return boost::dynamic_pointer_cast<MidiRegion>(region);
+}
+
+void 
+MidiTimeAxisView::start_step_editing ()
+{
+        if (!_step_editor) {
+                _step_editor = new StepEditor (_editor, midi_track(), *this);
+        }
+
+        _step_editor->start_step_editing ();
+
+}
+void 
+MidiTimeAxisView::stop_step_editing ()
+{
+        if (_step_editor) {
+                _step_editor->stop_step_editing ();
+        }
+}
diff --git a/gtk2_ardour/midi_time_axis.h b/gtk2_ardour/midi_time_axis.h
index 63372b9218..73c48f2613 100644
--- a/gtk2_ardour/midi_time_axis.h
+++ b/gtk2_ardour/midi_time_axis.h
@@ -54,6 +54,7 @@ class MidiStreamView;
 class MidiScroomer;
 class PianoRollHeader;
 class StepEntry;
+class StepEditor;
 
 class MidiTimeAxisView : public RouteTimeAxisView
 {
@@ -87,28 +88,14 @@ class MidiTimeAxisView : public RouteTimeAxisView
 		return _midi_patch_settings_changed;
 	}
 
-	void check_step_edit ();
-	void step_edit_rest (Evoral::MusicalTime beats);
-        void step_edit_beat_sync ();
-        void step_edit_bar_sync ();
-        int  step_add_bank_change (uint8_t channel, uint8_t bank);
-        int  step_add_program_change (uint8_t channel, uint8_t program);
-        int  step_add_note (uint8_t channel, uint8_t pitch, uint8_t velocity, 
-                            Evoral::MusicalTime beat_duration);
-        void step_edit_sustain (Evoral::MusicalTime beats);
-        bool step_edit_within_triplet () const;
-        void step_edit_toggle_triplet ();
-        bool step_edit_within_chord () const;
-        void step_edit_toggle_chord ();
-        void reset_step_edit_beat_pos ();
-        void resync_step_edit_to_edit_point ();
-        void move_step_edit_beat_pos (Evoral::MusicalTime beats);
-        void set_step_edit_cursor_width (Evoral::MusicalTime beats);
         
 	const MidiMultipleChannelSelector& channel_selector() { return _channel_selector; }
 
 	Gtk::CheckMenuItem* automation_child_menu_item (Evoral::Parameter);
 
+        StepEditor* step_editor() { return _step_editor; }
+        void check_step_edit ();
+
   protected:
 	void start_step_editing ();
 	void stop_step_editing ();
@@ -149,16 +136,6 @@ class MidiTimeAxisView : public RouteTimeAxisView
 	Gtk::CheckMenuItem*          _midi_thru_item;
 	Gtk::Menu*                    default_channel_menu;
 
-	nframes64_t step_edit_insert_position;
-	Evoral::MusicalTime step_edit_beat_pos;
-	boost::shared_ptr<ARDOUR::MidiRegion> step_edit_region;
-	MidiRegionView* step_edit_region_view;
-        uint8_t _step_edit_triplet_countdown;
-        bool    _step_edit_within_chord;
-        Evoral::MusicalTime _step_edit_chord_duration;
-        void region_removed (boost::weak_ptr<ARDOUR::Region>);
-        void playlist_changed ();
-        PBD::ScopedConnection step_edit_region_connection;
 
 	Gtk::Menu* build_def_channel_menu();
 	void set_default_channel (int);
@@ -184,11 +161,7 @@ class MidiTimeAxisView : public RouteTimeAxisView
 	/** parameter -> menu item map for the controller menu */
 	ParameterMenuMap _controller_menu_map;
 
-        StepEntry* step_editor;
-        bool step_editor_hidden (GdkEventAny*);
-        void step_editor_hide ();
-        void resync_step_edit_position ();
-        void prepare_step_edit_region ();
+        StepEditor* _step_editor;
 };
 
 #endif /* __ardour_midi_time_axis_h__ */
diff --git a/gtk2_ardour/step_editor.cc b/gtk2_ardour/step_editor.cc
new file mode 100644
index 0000000000..822af4c559
--- /dev/null
+++ b/gtk2_ardour/step_editor.cc
@@ -0,0 +1,395 @@
+#include "ardour/midi_track.h"
+#include "ardour/midi_region.h"
+#include "ardour/tempo.h"
+#include "ardour/types.h"
+
+#include "gui_thread.h"
+#include "midi_region_view.h"
+#include "public_editor.h"
+#include "step_editor.h"
+#include "step_entry.h"
+
+using namespace ARDOUR;
+using namespace Gtk;
+using namespace std;
+
+StepEditor::StepEditor (PublicEditor& e, boost::shared_ptr<MidiTrack> t, MidiTimeAxisView& mtv)
+        : _editor (e) 
+        , _track (t)
+        , step_editor (0)
+        , _mtv (mtv)
+{
+	step_edit_insert_position = 0;
+        _step_edit_triplet_countdown = 0;
+        _step_edit_within_chord = 0;
+        _step_edit_chord_duration = 0.0;
+        step_edit_region_view = 0;
+ 
+        _track->PlaylistChanged.connect (*this, invalidator (*this),
+                                         boost::bind (&StepEditor::playlist_changed, this),
+                                         gui_context());
+        playlist_changed ();
+}
+
+StepEditor::~StepEditor()
+{
+        delete step_editor;
+}
+
+void
+StepEditor::start_step_editing ()
+{
+        _step_edit_triplet_countdown = 0;
+        _step_edit_within_chord = 0;
+        _step_edit_chord_duration = 0.0;
+        step_edit_region.reset ();
+        step_edit_region_view = 0;
+
+        resync_step_edit_position ();
+        prepare_step_edit_region ();
+        reset_step_edit_beat_pos ();
+
+        assert (step_edit_region);
+        assert (step_edit_region_view);
+
+        if (step_editor == 0) {
+                step_editor = new StepEntry (*this);
+                step_editor->signal_delete_event().connect (sigc::mem_fun (*this, &StepEditor::step_editor_hidden));
+                step_editor->signal_hide().connect (sigc::mem_fun (*this, &StepEditor::step_editor_hide));
+        }
+
+        step_edit_region_view->show_step_edit_cursor (step_edit_beat_pos);
+        step_edit_region_view->set_step_edit_cursor_width (step_editor->note_length());
+
+        step_editor->set_position (WIN_POS_MOUSE);
+        step_editor->present ();
+}
+
+void
+StepEditor::resync_step_edit_position ()
+{
+	step_edit_insert_position = _editor.get_preferred_edit_position ();
+}
+
+void
+StepEditor::resync_step_edit_to_edit_point ()
+{
+        resync_step_edit_position ();
+        if (step_edit_region) {
+                reset_step_edit_beat_pos ();
+        }
+}
+
+void
+StepEditor::prepare_step_edit_region ()
+{
+        boost::shared_ptr<Region> r = _track->playlist()->top_region_at (step_edit_insert_position);
+
+        if (r) {
+                step_edit_region = boost::dynamic_pointer_cast<MidiRegion>(r);
+        }
+
+	if (step_edit_region) {
+		RegionView* rv = _mtv.midi_view()->find_view (step_edit_region);
+		step_edit_region_view = dynamic_cast<MidiRegionView*> (rv);
+
+	} else {
+                step_edit_region = _mtv.add_region (step_edit_insert_position);
+                RegionView* rv = _mtv.midi_view()->find_view (step_edit_region);
+                step_edit_region_view = dynamic_cast<MidiRegionView*>(rv);
+        }
+}
+
+
+void
+StepEditor::reset_step_edit_beat_pos ()
+{
+        assert (step_edit_region);
+        assert (step_edit_region_view);
+
+        framecnt_t frames_from_start = _editor.get_preferred_edit_position() - step_edit_region->position();
+        
+        if (frames_from_start < 0) {
+                /* this can happen with snap enabled, and the edit point == Playhead. we snap the
+                   position of the new region, and it can end up after the edit point.
+                */
+                frames_from_start = 0;
+        }
+        
+        step_edit_beat_pos = step_edit_region_view->frames_to_beats (frames_from_start);
+        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+}
+
+bool
+StepEditor::step_editor_hidden (GdkEventAny*)
+{
+        step_editor_hide ();
+        return true;
+}
+
+void
+StepEditor::step_editor_hide ()
+{
+        /* everything else will follow the change in the model */
+	_track->set_step_editing (false);
+}
+
+void
+StepEditor::stop_step_editing ()
+{
+        if (step_editor) {
+                step_editor->hide ();
+        }
+
+        if (step_edit_region_view) {
+                step_edit_region_view->hide_step_edit_cursor();
+        }
+
+        step_edit_region.reset ();
+}
+
+void
+StepEditor::check_step_edit ()
+{
+	MidiRingBuffer<nframes_t>& incoming (_track->step_edit_ring_buffer());
+	uint8_t* buf;
+	uint32_t bufsize = 32;
+
+	buf = new uint8_t[bufsize];
+
+	while (incoming.read_space()) {
+		nframes_t time;
+		Evoral::EventType type;
+		uint32_t size;
+
+		incoming.read_prefix (&time, &type, &size);
+
+		if (size > bufsize) {
+			delete [] buf;
+			bufsize = size;
+			buf = new uint8_t[bufsize];
+		}
+
+		incoming.read_contents (size, buf);
+
+		if ((buf[0] & 0xf0) == MIDI_CMD_NOTE_ON) {
+                        step_add_note (buf[0] & 0xf, buf[1], buf[2], 0.0);
+		}
+	}
+}
+
+int
+StepEditor::step_add_bank_change (uint8_t channel, uint8_t bank)
+{
+        return 0;
+}
+
+int
+StepEditor::step_add_program_change (uint8_t channel, uint8_t program)
+{
+        return 0;
+}
+
+void
+StepEditor::step_edit_sustain (Evoral::MusicalTime beats)
+{
+        if (step_edit_region_view) {
+                step_edit_region_view->step_sustain (beats);
+        }
+}
+
+void
+StepEditor::move_step_edit_beat_pos (Evoral::MusicalTime beats)
+{
+        if (beats > 0.0) {
+                step_edit_beat_pos = min (step_edit_beat_pos + beats, 
+                                          step_edit_region_view->frames_to_beats (step_edit_region->length()));
+        } else if (beats < 0.0) {
+                if (beats < step_edit_beat_pos) {
+                        step_edit_beat_pos += beats; // its negative, remember
+                } else {
+                        step_edit_beat_pos = 0;
+                }
+        }
+        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+}
+
+int
+StepEditor::step_add_note (uint8_t channel, uint8_t pitch, uint8_t velocity, Evoral::MusicalTime beat_duration)
+{
+        /* do these things in case undo removed the step edit region
+        */
+        if (!step_edit_region) {
+                resync_step_edit_position ();
+                prepare_step_edit_region ();
+                reset_step_edit_beat_pos ();
+                step_edit_region_view->show_step_edit_cursor (step_edit_beat_pos);
+                step_edit_region_view->set_step_edit_cursor_width (step_editor->note_length());
+        }
+
+        assert (step_edit_region);
+        assert (step_edit_region_view);
+                
+        if (beat_duration == 0.0) {
+                bool success;
+                beat_duration = _editor.get_grid_type_as_beats (success, step_edit_insert_position);
+                
+                if (!success) {
+                        return -1;
+                }
+        }
+        
+        MidiStreamView* msv = _mtv.midi_view();
+        
+        /* make sure its visible on the vertical axis */
+        
+        if (pitch < msv->lowest_note() || pitch > msv->highest_note()) {
+                msv->update_note_range (pitch);
+                msv->set_note_range (MidiStreamView::ContentsRange);
+        }
+        
+        /* make sure its visible on the horizontal axis */
+        
+        nframes64_t fpos = step_edit_region->position() + 
+                step_edit_region_view->beats_to_frames (step_edit_beat_pos + beat_duration);
+        
+        if (fpos >= (_editor.leftmost_position() + _editor.current_page_frames())) {
+                _editor.reset_x_origin (fpos - (_editor.current_page_frames()/4));
+        }
+        
+        step_edit_region_view->step_add_note (channel, pitch, velocity, step_edit_beat_pos, beat_duration);
+        
+        if (_step_edit_triplet_countdown > 0) {
+                _step_edit_triplet_countdown--;
+                
+                if (_step_edit_triplet_countdown == 0) {
+                        _step_edit_triplet_countdown = 3;
+                }
+        }
+        
+        if (!_step_edit_within_chord) {
+                step_edit_beat_pos += beat_duration;
+                step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+        } else {
+                step_edit_beat_pos += 1.0/Meter::ticks_per_beat; // tiny, but no longer overlapping
+                _step_edit_chord_duration = max (_step_edit_chord_duration, beat_duration);
+        }
+
+        return 0;
+}
+
+void
+StepEditor::set_step_edit_cursor_width (Evoral::MusicalTime beats)
+{
+        if (step_edit_region_view) {
+                step_edit_region_view->set_step_edit_cursor_width (beats);
+        }
+}
+
+bool
+StepEditor::step_edit_within_triplet() const
+{
+        return _step_edit_triplet_countdown > 0;
+}
+
+bool
+StepEditor::step_edit_within_chord() const
+{
+        return _step_edit_within_chord;
+}
+
+void
+StepEditor::step_edit_toggle_triplet ()
+{
+        if (_step_edit_triplet_countdown == 0) {
+                _step_edit_within_chord = false;
+                _step_edit_triplet_countdown = 3;
+        } else {
+                _step_edit_triplet_countdown = 0;
+        }
+}
+
+void
+StepEditor::step_edit_toggle_chord ()
+{
+        if (_step_edit_within_chord) {
+                _step_edit_within_chord = false;
+                step_edit_beat_pos += _step_edit_chord_duration;
+                step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+        } else {
+                _step_edit_triplet_countdown = 0;
+                _step_edit_within_chord = true;
+        }
+}
+
+void
+StepEditor::step_edit_rest (Evoral::MusicalTime beats)
+{
+	bool success;
+
+        if (beats == 0.0) {
+                beats = _editor.get_grid_type_as_beats (success, step_edit_insert_position);
+        } else {
+                success = true;
+        }
+
+        if (success) {
+                step_edit_beat_pos += beats;
+                step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+        }
+}
+
+void 
+StepEditor::step_edit_beat_sync ()
+{
+        step_edit_beat_pos = ceil (step_edit_beat_pos);
+        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+}
+
+void 
+StepEditor::step_edit_bar_sync ()
+{
+        Session* _session = _mtv.session ();
+
+        if (!_session || !step_edit_region_view || !step_edit_region) {
+                return;
+        }
+
+        framepos_t fpos = step_edit_region->position() + 
+                step_edit_region_view->beats_to_frames (step_edit_beat_pos);
+        fpos = _session->tempo_map().round_to_bar (fpos, 1);
+        step_edit_beat_pos = ceil (step_edit_region_view->frames_to_beats (fpos - step_edit_region->position()));
+        step_edit_region_view->move_step_edit_cursor (step_edit_beat_pos);
+}
+
+void
+StepEditor::playlist_changed ()
+{
+        step_edit_region_connection.disconnect ();
+        _track->playlist()->RegionRemoved.connect (step_edit_region_connection, invalidator (*this),
+                                                   ui_bind (&StepEditor::region_removed, this, _1),
+                                                   gui_context());
+}
+
+void
+StepEditor::region_removed (boost::weak_ptr<Region> wr)
+{
+        boost::shared_ptr<Region> r (wr.lock());
+ 
+        if (!r) {
+                return;
+        }
+
+        if (step_edit_region == r) {
+                step_edit_region.reset();
+                step_edit_region_view = 0;
+                // force a recompute of the insert position
+                step_edit_beat_pos = -1.0;
+        }
+}
+
+string
+StepEditor::name() const 
+{
+        return _track->name();
+}
diff --git a/gtk2_ardour/step_editor.h b/gtk2_ardour/step_editor.h
new file mode 100644
index 0000000000..00be7890a3
--- /dev/null
+++ b/gtk2_ardour/step_editor.h
@@ -0,0 +1,73 @@
+#ifndef __pbd__step_editor_h__
+#define __pbd__step_editor_h__
+
+#include <string>
+
+#include <gdk/gdk.h>
+#include <sigc++/trackable.h>
+
+#include "pbd/signals.h"
+#include "evoral/types.hpp"
+
+namespace ARDOUR {
+        class MidiTrack;
+        class MidiRegion;
+}
+
+class MidiRegionView;
+class MidiTimeAxisView;
+class PublicEditor;
+class StepEntry;
+
+class StepEditor : public PBD::ScopedConnectionList, public sigc::trackable
+{
+  public:
+        StepEditor (PublicEditor&, boost::shared_ptr<ARDOUR::MidiTrack>, MidiTimeAxisView&);
+        virtual ~StepEditor ();
+
+	void check_step_edit ();
+	void step_edit_rest (Evoral::MusicalTime beats);
+        void step_edit_beat_sync ();
+        void step_edit_bar_sync ();
+        int  step_add_bank_change (uint8_t channel, uint8_t bank);
+        int  step_add_program_change (uint8_t channel, uint8_t program);
+        int  step_add_note (uint8_t channel, uint8_t pitch, uint8_t velocity, 
+                            Evoral::MusicalTime beat_duration);
+        void step_edit_sustain (Evoral::MusicalTime beats);
+        bool step_edit_within_triplet () const;
+        void step_edit_toggle_triplet ();
+        bool step_edit_within_chord () const;
+        void step_edit_toggle_chord ();
+        void reset_step_edit_beat_pos ();
+        void resync_step_edit_to_edit_point ();
+        void move_step_edit_beat_pos (Evoral::MusicalTime beats);
+        void set_step_edit_cursor_width (Evoral::MusicalTime beats);
+
+        std::string name() const;
+
+	void start_step_editing ();
+	void stop_step_editing ();
+
+  private:
+        ARDOUR::framepos_t                    step_edit_insert_position;
+	Evoral::MusicalTime                   step_edit_beat_pos;
+	boost::shared_ptr<ARDOUR::MidiRegion> step_edit_region;
+	MidiRegionView*                       step_edit_region_view;
+        uint8_t                              _step_edit_triplet_countdown;
+        bool                                 _step_edit_within_chord;
+        Evoral::MusicalTime                  _step_edit_chord_duration;
+        PBD::ScopedConnection                 step_edit_region_connection;
+        PublicEditor&                        _editor;
+        boost::shared_ptr<ARDOUR::MidiTrack> _track;
+        StepEntry*                            step_editor;
+        MidiTimeAxisView&                    _mtv;
+
+        void region_removed (boost::weak_ptr<ARDOUR::Region>);
+        void playlist_changed ();
+        bool step_editor_hidden (GdkEventAny*);
+        void step_editor_hide ();
+        void resync_step_edit_position ();
+        void prepare_step_edit_region ();
+};
+
+#endif /* __pbd__step_editor_h__ */
diff --git a/gtk2_ardour/step_entry.cc b/gtk2_ardour/step_entry.cc
index d3ecca434c..1fd6b37cfb 100644
--- a/gtk2_ardour/step_entry.cc
+++ b/gtk2_ardour/step_entry.cc
@@ -31,6 +31,7 @@
 #include "ardour_ui.h"
 #include "midi_channel_selector.h"
 #include "midi_time_axis.h"
+#include "step_editor.h"
 #include "step_entry.h"
 #include "utils.h"
 
@@ -55,8 +56,8 @@ _rest_event_handler (GtkWidget* widget, gpointer arg)
 	((StepEntry*)arg)->rest_event_handler ();
 }
 
-StepEntry::StepEntry (MidiTimeAxisView& mtv)
-	: ArdourDialog (string_compose (_("Step Entry: %1"), mtv.name()))
+StepEntry::StepEntry (StepEditor& seditor)
+	: ArdourDialog (string_compose (_("Step Entry: %1"), seditor.name()))
         , _current_note_length (1.0)
         , _current_note_velocity (64)
 	, triplet_button ("3")
@@ -84,17 +85,18 @@ StepEntry::StepEntry (MidiTimeAxisView& mtv)
         , program_button (_("+"))
 	, _piano (0)
 	, piano (0)
-	, _mtv (&mtv)
+	, se (&seditor)
 {
         register_actions ();
         load_bindings ();
 
+#if 0
 	/* set channel selector to first selected channel. if none
 	   are selected, it will remain at the value set in its
 	   constructor, above (1)
 	*/
 
-	uint16_t chn_mask = _mtv->channel_selector().get_selected_channels();
+	uint16_t chn_mask = se->channel_selector().get_selected_channels();
         
 	for (uint32_t i = 0; i < 16; ++i) {
 		if (chn_mask & (1<<i)) {
@@ -103,6 +105,8 @@ StepEntry::StepEntry (MidiTimeAxisView& mtv)
 		}
 	}
 
+#endif
+
 	RadioButtonGroup length_group = length_1_button.get_group();
 	length_2_button.set_group (length_group);
 	length_4_button.set_group (length_group);
@@ -510,7 +514,7 @@ StepEntry::on_key_release_event (GdkEventKey* ev)
 void
 StepEntry::rest_event_handler ()
 {
-	_mtv->step_edit_rest (0.0);
+	se->step_edit_rest (0.0);
 }
 
 Evoral::MusicalTime
@@ -565,13 +569,13 @@ StepEntry::on_show ()
 void
 StepEntry::beat_resync_click ()
 {
-	_mtv->step_edit_beat_sync ();
+	se->step_edit_beat_sync ();
 }
 
 void
 StepEntry::bar_resync_click ()
 {
-        _mtv->step_edit_bar_sync ();
+        se->step_edit_bar_sync ();
 }
 
 void
@@ -703,13 +707,13 @@ StepEntry::load_bindings ()
 void
 StepEntry::toggle_triplet ()
 {
-        _mtv->set_step_edit_cursor_width (note_length());
+        se->set_step_edit_cursor_width (note_length());
 }
 
 void
 StepEntry::toggle_chord ()
 {
-        _mtv->step_edit_toggle_chord ();
+        se->step_edit_toggle_chord ();
 }
 
 void
@@ -756,37 +760,37 @@ StepEntry::dot_value_change ()
         dot2_button.set_inconsistent (inconsistent);
         dot3_button.set_inconsistent (inconsistent);
 
-        _mtv->set_step_edit_cursor_width (note_length());
+        se->set_step_edit_cursor_width (note_length());
 }
 
 void
 StepEntry::program_click ()
 {
-        _mtv->step_add_program_change (note_channel(), (int8_t) floor (program_adjustment.get_value()));
+        se->step_add_program_change (note_channel(), (int8_t) floor (program_adjustment.get_value()));
 }
 
 void
 StepEntry::bank_click ()
 {
-        _mtv->step_add_bank_change (note_channel(), (int8_t) floor (bank_adjustment.get_value()));
+        se->step_add_bank_change (note_channel(), (int8_t) floor (bank_adjustment.get_value()));
 }
 
 void
 StepEntry::insert_rest ()
 {
-	_mtv->step_edit_rest (note_length());
+	se->step_edit_rest (note_length());
 }
 
 void
 StepEntry::insert_grid_rest ()
 {
-	_mtv->step_edit_rest (0.0);
+	se->step_edit_rest (0.0);
 }
 
 void
 StepEntry::insert_note (uint8_t note)
 {
-	_mtv->step_add_note (note_channel(), note, note_velocity(), note_length());
+	se->step_add_note (note_channel(), note, note_velocity(), note_length());
 }
 void
 StepEntry::insert_c ()
@@ -972,7 +976,7 @@ StepEntry::length_value_change ()
         length_32_button.set_inconsistent (inconsistent);
         length_64_button.set_inconsistent (inconsistent);
 
-        _mtv->set_step_edit_cursor_width (note_length());
+        se->set_step_edit_cursor_width (note_length());
 }
 
 bool
@@ -1132,17 +1136,17 @@ StepEntry::octave_n (int n)
 void
 StepEntry::do_sustain ()
 {
-        _mtv->step_edit_sustain (note_length());
+        se->step_edit_sustain (note_length());
 }
 
 void
 StepEntry::back ()
 {
-        _mtv->move_step_edit_beat_pos (-note_length());
+        se->move_step_edit_beat_pos (-note_length());
 }
 
 void
 StepEntry::sync_to_edit_point ()
 {
-        _mtv->resync_step_edit_to_edit_point ();
+        se->resync_step_edit_to_edit_point ();
 }
diff --git a/gtk2_ardour/step_entry.h b/gtk2_ardour/step_entry.h
index 934e5e5c18..e534c83e01 100644
--- a/gtk2_ardour/step_entry.h
+++ b/gtk2_ardour/step_entry.h
@@ -30,12 +30,12 @@
 #include "ardour_dialog.h"
 #include "gtk_pianokeyboard.h"
 
-class MidiTimeAxisView;
+class StepEditor;
 
 class StepEntry : public ArdourDialog
 {
   public:
-        StepEntry (MidiTimeAxisView&);
+        StepEntry (StepEditor&);
         ~StepEntry ();
 
         void note_off_event_handler (int note);
@@ -124,7 +124,7 @@ class StepEntry : public ArdourDialog
 
         PianoKeyboard* _piano;
         Gtk::Widget* piano;
-        MidiTimeAxisView* _mtv;
+        StepEditor*   se;
 
         void bank_click ();
         void program_click ();
diff --git a/gtk2_ardour/wscript b/gtk2_ardour/wscript
index 5ec8ac5726..d87e31a604 100644
--- a/gtk2_ardour/wscript
+++ b/gtk2_ardour/wscript
@@ -190,6 +190,7 @@ gtk2_ardour_sources = [
 	'simplerect.cc',
 	'splash.cc',
 	'startup.cc',
+        'step_editor.cc',
         'step_entry.cc',
 	'streamview.cc',
 	'strip_silence_dialog.cc',