livetrax/gtk2_ardour/midi_region_view.cc

/*
    Copyright (C) 2001-2011 Paul Davis
    Author: David Robillard

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <cmath>
#include <cassert>
#include <algorithm>
#include <ostream>

#include <gtkmm.h>

#include "gtkmm2ext/gtk_ui.h"

#include <sigc++/signal.h>

#include "pbd/memento_command.h"
#include "pbd/stateful_diff_command.h"

#include "ardour/playlist.h"
#include "ardour/tempo.h"
#include "ardour/midi_region.h"
#include "ardour/midi_source.h"
#include "ardour/midi_model.h"
#include "ardour/midi_patch_manager.h"
#include "ardour/session.h"

#include "evoral/Parameter.hpp"
#include "evoral/MIDIParameters.hpp"
#include "evoral/MIDIEvent.hpp"
#include "evoral/Control.hpp"
#include "evoral/midi_util.h"

#include "automation_region_view.h"
#include "automation_time_axis.h"
#include "canvas-hit.h"
#include "canvas-note.h"
#include "canvas_patch_change.h"
#include "debug.h"
#include "editor.h"
#include "editor_drag.h"
#include "ghostregion.h"
#include "gui_thread.h"
#include "keyboard.h"
#include "midi_channel_dialog.h"
#include "midi_cut_buffer.h"
#include "midi_list_editor.h"
#include "midi_region_view.h"
#include "midi_streamview.h"
#include "midi_time_axis.h"
#include "midi_util.h"
#include "mouse_cursors.h"
#include "note_player.h"
#include "public_editor.h"
#include "rgb_macros.h"
#include "selection.h"
#include "simpleline.h"
#include "streamview.h"
#include "utils.h"
#include "patch_change_dialog.h"
#include "verbose_cursor.h"

#include "i18n.h"

using namespace ARDOUR;
using namespace PBD;
using namespace Editing;
using namespace ArdourCanvas;
using Gtkmm2ext::Keyboard;

PBD::Signal1<void, MidiRegionView *> MidiRegionView::SelectionCleared;

#define MIDI_BP_ZERO ((Config->get_first_midi_bank_is_zero())?0:1)

MidiRegionView::MidiRegionView (ArdourCanvas::Group *parent, RouteTimeAxisView &tv,
                                boost::shared_ptr<MidiRegion> r, double spu, Gdk::Color const & basic_color)
	: RegionView (parent, tv, r, spu, basic_color)
	, _force_channel(-1)
	, _last_channel_selection(0xFFFF)
	, _current_range_min(0)
	, _current_range_max(0)
	, _active_notes(0)
	, _note_group(new ArdourCanvas::Group(*group))
	, _note_diff_command (0)
	, _ghost_note(0)
	, _step_edit_cursor (0)
	, _step_edit_cursor_width (1.0)
	, _step_edit_cursor_position (0.0)
	, _channel_selection_scoped_note (0)
	, _temporary_note_group (0)
	, _mouse_state(None)
	, _pressed_button(0)
	, _sort_needed (true)
	, _optimization_iterator (_events.end())
	, _list_editor (0)
	, _no_sound_notes (false)
	, _last_event_x (0)
	, _last_event_y (0)
	, pre_enter_cursor (0)
	, pre_press_cursor (0)
{
	_note_group->raise_to_top();
	PublicEditor::DropDownKeys.connect (sigc::mem_fun (*this, &MidiRegionView::drop_down_keys));

	Config->ParameterChanged.connect (*this, invalidator (*this), ui_bind (&MidiRegionView::parameter_changed, this, _1), gui_context());
	connect_to_diskstream ();

	SelectionCleared.connect (_selection_cleared_connection, invalidator (*this), ui_bind (&MidiRegionView::selection_cleared, this, _1), gui_context ());
}

MidiRegionView::MidiRegionView (ArdourCanvas::Group *parent, RouteTimeAxisView &tv,
                                boost::shared_ptr<MidiRegion> r, double spu, Gdk::Color& basic_color,
                                TimeAxisViewItem::Visibility visibility)
	: RegionView (parent, tv, r, spu, basic_color, false, visibility)
	, _force_channel(-1)
	, _last_channel_selection(0xFFFF)
	, _current_range_min(0)
	, _current_range_max(0)
	, _active_notes(0)
	, _note_group(new ArdourCanvas::Group(*parent))
	, _note_diff_command (0)
	, _ghost_note(0)
	, _step_edit_cursor (0)
	, _step_edit_cursor_width (1.0)
	, _step_edit_cursor_position (0.0)
	, _channel_selection_scoped_note (0)
	, _temporary_note_group (0)
	, _mouse_state(None)
	, _pressed_button(0)
	, _sort_needed (true)
	, _optimization_iterator (_events.end())
	, _list_editor (0)
	, _no_sound_notes (false)
	, _last_event_x (0)
	, _last_event_y (0)
	, pre_enter_cursor (0)
	, pre_press_cursor (0)
{
	_note_group->raise_to_top();
	PublicEditor::DropDownKeys.connect (sigc::mem_fun (*this, &MidiRegionView::drop_down_keys));

	connect_to_diskstream ();

	SelectionCleared.connect (_selection_cleared_connection, invalidator (*this), ui_bind (&MidiRegionView::selection_cleared, this, _1), gui_context ());
}

void
MidiRegionView::parameter_changed (std::string const & p)
{
	if (p == "diplay-first-midi-bank-as-zero") {
		if (_enable_display) {
			redisplay_model();
		}
	}
}

MidiRegionView::MidiRegionView (const MidiRegionView& other)
	: sigc::trackable(other)
	, RegionView (other)
	, _force_channel(-1)
	, _last_channel_selection(0xFFFF)
	, _current_range_min(0)
	, _current_range_max(0)
	, _active_notes(0)
	, _note_group(new ArdourCanvas::Group(*get_canvas_group()))
	, _note_diff_command (0)
	, _ghost_note(0)
	, _step_edit_cursor (0)
	, _step_edit_cursor_width (1.0)
	, _step_edit_cursor_position (0.0)
	, _channel_selection_scoped_note (0)
	, _temporary_note_group (0)
	, _mouse_state(None)
	, _pressed_button(0)
	, _sort_needed (true)
	, _optimization_iterator (_events.end())
	, _list_editor (0)
	, _no_sound_notes (false)
	, _last_event_x (0)
	, _last_event_y (0)
	, pre_enter_cursor (0)
	, pre_press_cursor (0)
{
	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);
}

MidiRegionView::MidiRegionView (const MidiRegionView& other, boost::shared_ptr<MidiRegion> region)
	: RegionView (other, boost::shared_ptr<Region> (region))
	, _force_channel(-1)
	, _last_channel_selection(0xFFFF)
	, _current_range_min(0)
	, _current_range_max(0)
	, _active_notes(0)
	, _note_group(new ArdourCanvas::Group(*get_canvas_group()))
	, _note_diff_command (0)
	, _ghost_note(0)
	, _step_edit_cursor (0)
	, _step_edit_cursor_width (1.0)
	, _step_edit_cursor_position (0.0)
	, _channel_selection_scoped_note (0)
	, _temporary_note_group (0)
	, _mouse_state(None)
	, _pressed_button(0)
	, _sort_needed (true)
	, _optimization_iterator (_events.end())
	, _list_editor (0)
	, _no_sound_notes (false)
	, _last_event_x (0)
	, _last_event_y (0)
	, pre_enter_cursor (0)
	, pre_press_cursor (0)
{
	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, true);
}

void
MidiRegionView::init (Gdk::Color const & basic_color, bool wfd)
{
	PublicEditor::DropDownKeys.connect (sigc::mem_fun (*this, &MidiRegionView::drop_down_keys));

	CanvasNoteEvent::CanvasNoteEventDeleted.connect (note_delete_connection, MISSING_INVALIDATOR,
	                                                 ui_bind (&MidiRegionView::maybe_remove_deleted_note_from_selection, this, _1),
	                                                 gui_context());

	if (wfd) {
		midi_region()->midi_source(0)->load_model();
	}

	_model = midi_region()->midi_source(0)->model();
	_enable_display = false;

	RegionView::init (basic_color, false);

	compute_colors (basic_color);

	set_height (trackview.current_height());

	region_muted ();
	region_sync_changed ();
	region_resized (ARDOUR::bounds_change);
	region_locked ();

	reset_width_dependent_items (_pixel_width);

	set_colors ();

	_enable_display = true;
	if (_model) {
		if (wfd) {
			display_model (_model);
		}
	}

	group->raise_to_top();
	group->signal_event().connect(
		sigc::mem_fun(this, &MidiRegionView::canvas_event), false);

	midi_view()->signal_channel_mode_changed().connect(
		sigc::mem_fun(this, &MidiRegionView::midi_channel_mode_changed));

	midi_view()->signal_midi_patch_settings_changed().connect(
		sigc::mem_fun(this, &MidiRegionView::midi_patch_settings_changed));

	trackview.editor().SnapChanged.connect(snap_changed_connection, invalidator(*this),
	                                       ui_bind(&MidiRegionView::snap_changed, this),
	                                       gui_context());

	Config->ParameterChanged.connect (*this, invalidator (*this), ui_bind (&MidiRegionView::parameter_changed, this, _1), gui_context());
	connect_to_diskstream ();

	SelectionCleared.connect (_selection_cleared_connection, invalidator (*this), ui_bind (&MidiRegionView::selection_cleared, this, _1), gui_context ());
}

const boost::shared_ptr<ARDOUR::MidiRegion>
MidiRegionView::midi_region() const
{
	return boost::dynamic_pointer_cast<ARDOUR::MidiRegion>(_region);
}

void
MidiRegionView::connect_to_diskstream ()
{
	midi_view()->midi_track()->DataRecorded.connect(
		*this, invalidator(*this),
		ui_bind(&MidiRegionView::data_recorded, this, _1),
		gui_context());
}

bool
MidiRegionView::canvas_event(GdkEvent* ev)
{
	switch (ev->type) {
	case GDK_ENTER_NOTIFY:
	case GDK_LEAVE_NOTIFY:
		_last_event_x = ev->crossing.x;
		_last_event_y = ev->crossing.y;
		break;
	case GDK_MOTION_NOTIFY:
		_last_event_x = ev->motion.x;
		_last_event_y = ev->motion.y;
		break;
	default:
		break;
	}

	if (ev->type == GDK_2BUTTON_PRESS) {
		return trackview.editor().toggle_internal_editing_from_double_click (ev);
	}

	if (!trackview.editor().internal_editing()) {
		return false;
	}

	switch (ev->type) {
	case GDK_SCROLL:
		return scroll (&ev->scroll);

	case GDK_KEY_PRESS:
		return key_press (&ev->key);

	case GDK_KEY_RELEASE:
		return key_release (&ev->key);

	case GDK_BUTTON_PRESS:
		return button_press (&ev->button);

	case GDK_BUTTON_RELEASE:
		return button_release (&ev->button);

	case GDK_ENTER_NOTIFY:
		return enter_notify (&ev->crossing);

	case GDK_LEAVE_NOTIFY:
		return leave_notify (&ev->crossing);

	case GDK_MOTION_NOTIFY:
		return motion (&ev->motion);

	default:
		break;
	}

	return false;
}

void
MidiRegionView::remove_ghost_note ()
{
	delete _ghost_note;
	_ghost_note = 0;
}

bool
MidiRegionView::enter_notify (GdkEventCrossing* ev)
{
	trackview.editor().MouseModeChanged.connect (
		_mouse_mode_connection, invalidator (*this), ui_bind (&MidiRegionView::mouse_mode_changed, this), gui_context ()
		);

	if (trackview.editor().current_mouse_mode() == MouseDraw && _mouse_state != AddDragging) {
		create_ghost_note (ev->x, ev->y);
	}

	if (!trackview.editor().internal_editing()) {
		Keyboard::magic_widget_drop_focus();
	} else {
		Keyboard::magic_widget_grab_focus();
		group->grab_focus();
	}

	return false;
}

bool
MidiRegionView::leave_notify (GdkEventCrossing*)
{
	_mouse_mode_connection.disconnect ();

	trackview.editor().verbose_cursor()->hide ();
	remove_ghost_note ();

	return false;
}

void
MidiRegionView::mouse_mode_changed ()
{
	if (trackview.editor().current_mouse_mode() == MouseDraw && trackview.editor().internal_editing()) {
		create_ghost_note (_last_event_x, _last_event_y);
	} else {
		remove_ghost_note ();
		trackview.editor().verbose_cursor()->hide ();
	}

	if (!trackview.editor().internal_editing()) {
		Keyboard::magic_widget_drop_focus();
	} else {
		Keyboard::magic_widget_grab_focus();
		group->grab_focus();
	}
}

bool
MidiRegionView::button_press (GdkEventButton* ev)
{
	if (ev->button != 1) {
		return false;
	}

	Editor* editor = dynamic_cast<Editor *> (&trackview.editor());
	MouseMode m = editor->current_mouse_mode();

	if (m == MouseObject && Keyboard::modifier_state_contains (ev->state, Keyboard::insert_note_modifier())) {
		pre_press_cursor = editor->get_canvas_cursor ();
		editor->set_canvas_cursor (editor->cursors()->midi_pencil);
	} 

	if (_mouse_state != SelectTouchDragging) {
		
		_pressed_button = ev->button;
		_mouse_state = Pressed;
		
		return true;
	}

	_pressed_button = ev->button;

	return true;
}

bool
MidiRegionView::button_release (GdkEventButton* ev)
{
	double event_x, event_y;

	if (ev->button != 1) {
		return false;
	}

	event_x = ev->x;
	event_y = ev->y;

	group->w2i(event_x, event_y);
	group->ungrab(ev->time);

	PublicEditor& editor = trackview.editor ();

	if (pre_press_cursor) {
		dynamic_cast<Editor*>(&editor)->set_canvas_cursor (pre_press_cursor, false);
		pre_press_cursor = 0;
	}

	switch (_mouse_state) {
	case Pressed: // Clicked

		switch (editor.current_mouse_mode()) {
		case MouseRange:
			/* no motion occured - simple click */
			clear_selection ();
			break;

		case MouseObject:
		case MouseTimeFX:
			{
				clear_selection();

				if (Keyboard::is_insert_note_event(ev)) {

					double event_x, event_y;

					event_x = ev->x;
					event_y = ev->y;
					group->w2i(event_x, event_y);

					bool success;
					Evoral::MusicalTime beats = editor.get_grid_type_as_beats (success, editor.pixel_to_frame (event_x));

					if (!success) {
						beats = 1;
					}

					/* Shorten the length by 1 tick so that we can add a new note at the next
					   grid snap without it overlapping this one.
					*/
					beats -= 1.0 / Timecode::BBT_Time::ticks_per_beat;

					create_note_at (editor.pixel_to_frame (event_x), event_y, beats, true);
				}

				break;
			}
		case MouseDraw:
			{
				bool success;
				Evoral::MusicalTime beats = editor.get_grid_type_as_beats (success, editor.pixel_to_frame (event_x));

				if (!success) {
					beats = 1;
				}

				/* Shorten the length by 1 tick so that we can add a new note at the next
				   grid snap without it overlapping this one.
				*/
				beats -= 1.0 / Timecode::BBT_Time::ticks_per_beat;
				
				create_note_at (editor.pixel_to_frame (event_x), event_y, beats, true);

				break;
			}
		default:
			break;
		}

		_mouse_state = None;
		break;

	case SelectRectDragging:
	case AddDragging:
		editor.drags()->end_grab ((GdkEvent *) ev);
		_mouse_state = None;
		create_ghost_note (ev->x, ev->y);
		break;


	default:
		break;
	}

	return false;
}

bool
MidiRegionView::motion (GdkEventMotion* ev)
{
	PublicEditor& editor = trackview.editor ();

	if (!_ghost_note && editor.current_mouse_mode() == MouseObject &&
	    Keyboard::modifier_state_contains (ev->state, Keyboard::insert_note_modifier()) &&
	    _mouse_state != AddDragging) {

		create_ghost_note (ev->x, ev->y);

	} else if (_ghost_note && editor.current_mouse_mode() == MouseObject &&
	           Keyboard::modifier_state_contains (ev->state, Keyboard::insert_note_modifier())) {

		update_ghost_note (ev->x, ev->y);

	} else if (_ghost_note && editor.current_mouse_mode() == MouseObject) {

		remove_ghost_note ();
		editor.verbose_cursor()->hide ();

	} else if (_ghost_note && editor.current_mouse_mode() == MouseDraw) {

		update_ghost_note (ev->x, ev->y);
	}

	/* any motion immediately hides velocity text that may have been visible */

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		(*i)->hide_velocity ();
	}

	switch (_mouse_state) {
	case Pressed:

		if (_pressed_button == 1) {
			
			MouseMode m = editor.current_mouse_mode();
			
			if (m == MouseDraw || (m == MouseObject && Keyboard::modifier_state_contains (ev->state, Keyboard::insert_note_modifier()))) {
			
				editor.drags()->set (new NoteCreateDrag (dynamic_cast<Editor *> (&editor), group, this), (GdkEvent *) ev);
				_mouse_state = AddDragging;
				remove_ghost_note ();
				editor.verbose_cursor()->hide ();
				return true;
			} else if (m == MouseObject) {
				
				editor.drags()->set (new MidiRubberbandSelectDrag (dynamic_cast<Editor *> (&editor), this), (GdkEvent *) ev);
				_mouse_state = SelectRectDragging;
				return true;
			} else if (m == MouseRange) {
				editor.drags()->set (new MidiVerticalSelectDrag (dynamic_cast<Editor *> (&editor), this), (GdkEvent *) ev);
				_mouse_state = SelectVerticalDragging;
				return true;
			}
		}

		return false;

	case SelectRectDragging:
	case SelectVerticalDragging:
	case AddDragging:
		editor.drags()->motion_handler ((GdkEvent *) ev, false);
		break;
		
	case SelectTouchDragging:
		return false;

	default:
		break;
	}

	return false;
}


bool
MidiRegionView::scroll (GdkEventScroll* ev)
{
	if (_selection.empty()) {
		return false;
	}

	if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
		/* XXX: bit of a hack; allow PrimaryModifier scroll through so that
		   it still works for zoom.
		*/
		return false;
	}

	trackview.editor().verbose_cursor()->hide ();

	bool fine = !Keyboard::modifier_state_equals (ev->state, Keyboard::SecondaryModifier);

	if (ev->direction == GDK_SCROLL_UP) {
		change_velocities (true, fine, false);
	} else if (ev->direction == GDK_SCROLL_DOWN) {
		change_velocities (false, fine, false);
	}
	return true;
}

bool
MidiRegionView::key_press (GdkEventKey* ev)
{
	/* since GTK bindings are generally activated on press, and since
	   detectable auto-repeat is the name of the game and only sends
	   repeated presses, carry out key actions at key press, not release.
	*/

	bool unmodified = Keyboard::no_modifier_keys_pressed (ev);
	
	if (unmodified && (ev->keyval == GDK_Alt_L || ev->keyval == GDK_Alt_R)) {
		_mouse_state = SelectTouchDragging;
		return true;

	} else if (ev->keyval == GDK_Escape && unmodified) {
		clear_selection();
		_mouse_state = None;

	} else if (unmodified && (ev->keyval == GDK_comma || ev->keyval == GDK_period)) {

		bool start = (ev->keyval == GDK_comma);
		bool end = (ev->keyval == GDK_period);
		bool shorter = Keyboard::modifier_state_contains (ev->state, Keyboard::PrimaryModifier);
		bool fine = Keyboard::modifier_state_contains (ev->state, Keyboard::SecondaryModifier);

		change_note_lengths (fine, shorter, 0.0, start, end);

		return true;

	} else if (ev->keyval == GDK_Delete && unmodified) {

		delete_selection();
		return true;

	} else if (ev->keyval == GDK_Tab) {

		if (Keyboard::modifier_state_contains (ev->state, Keyboard::PrimaryModifier)) {
			goto_previous_note (Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier));
		} else {
			goto_next_note (Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier));
		}
		return true;

	} else if (ev->keyval == GDK_ISO_Left_Tab) {

		/* Shift-TAB generates ISO Left Tab, for some reason */

		if (Keyboard::modifier_state_contains (ev->state, Keyboard::PrimaryModifier)) {
			goto_previous_note (Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier));
		} else {
			goto_next_note (Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier));
		}
		return true;



	} else if (ev->keyval == GDK_Up) {

		bool allow_smush = Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier);
		bool fine = !Keyboard::modifier_state_contains (ev->state, Keyboard::SecondaryModifier);

		if (Keyboard::modifier_state_contains (ev->state, Keyboard::PrimaryModifier)) {
			change_velocities (true, fine, allow_smush);
		} else {
			transpose (true, fine, allow_smush);
		}
		return true;

	} else if (ev->keyval == GDK_Down) {

		bool allow_smush = Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier);
		bool fine = !Keyboard::modifier_state_contains (ev->state, Keyboard::SecondaryModifier);

		if (Keyboard::modifier_state_contains (ev->state, Keyboard::PrimaryModifier)) {
			change_velocities (false, fine, allow_smush);
		} else {
			transpose (false, fine, allow_smush);
		}
		return true;

	} else if (ev->keyval == GDK_Left && unmodified) {

		nudge_notes (false);
		return true;

	} else if (ev->keyval == GDK_Right && unmodified) {

		nudge_notes (true);
		return true;

	} else if (ev->keyval == GDK_c && unmodified) {
		channel_edit ();
		return true;
	}

	return false;
}

bool
MidiRegionView::key_release (GdkEventKey* ev)
{
	if ((_mouse_state == SelectTouchDragging) && (ev->keyval == GDK_Alt_L || ev->keyval == GDK_Alt_R)) {
		_mouse_state = None;
		return true;
	}
	return false;
}

void
MidiRegionView::channel_edit ()
{
	bool first = true;
	uint8_t current_channel = 0;

	if (_selection.empty()) {
		return;
	}
	
	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		if (first) {
			current_channel = (*i)->note()->channel ();
			first = false;
		}
	}

	MidiChannelDialog channel_dialog (current_channel);
	int ret = channel_dialog.run ();

	switch (ret) {
	case Gtk::RESPONSE_OK:
		break;
	default:
		return;
	}

	uint8_t new_channel = channel_dialog.active_channel ();

	start_note_diff_command (_("channel edit"));

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
		Selection::iterator next = i;
		++next;
		change_note_channel (*i, new_channel);
		i = next;
	}

	apply_diff ();
}

void
MidiRegionView::show_list_editor ()
{
	if (!_list_editor) {
		_list_editor = new MidiListEditor (trackview.session(), midi_region(), midi_view()->midi_track());
	}
	_list_editor->present ();
}

/** Add a note to the model, and the view, at a canvas (click) coordinate.
 * \param t time in frames relative to the position of the region
 * \param y vertical position in pixels
 * \param length duration of the note in beats
 * \param snap_t true to snap t to the grid, otherwise false.
 */
void
MidiRegionView::create_note_at (framepos_t t, double y, double length, bool snap_t)
{
	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);
	MidiStreamView* const view = mtv->midi_view();

	double note = view->y_to_note(y);

	assert(note >= 0.0);
	assert(note <= 127.0);

	// Start of note in frames relative to region start
	if (snap_t) {
		framecnt_t grid_frames;
		t = snap_frame_to_grid_underneath (t, grid_frames);
	}

	assert (t >= 0);
	assert (length != 0);

	const boost::shared_ptr<NoteType> new_note (new NoteType (mtv->get_channel_for_add (),
	                                                          region_frames_to_region_beats(t + _region->start()), 
								  length,
	                                                          (uint8_t)note, 0x40));

	if (_model->contains (new_note)) {
		return;
	}

	view->update_note_range(new_note->note());

	MidiModel::NoteDiffCommand* cmd = _model->new_note_diff_command("add note");
	cmd->add (new_note);
	_model->apply_command(*trackview.session(), cmd);

	play_midi_note (new_note);
}

void
MidiRegionView::clear_events()
{
	clear_selection();

	MidiGhostRegion* gr;
	for (std::vector<GhostRegion*>::iterator g = ghosts.begin(); g != ghosts.end(); ++g) {
		if ((gr = dynamic_cast<MidiGhostRegion*>(*g)) != 0) {
			gr->clear_events();
		}
	}

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		delete *i;
	}

	_events.clear();
	_patch_changes.clear();
	_sys_exes.clear();
	_optimization_iterator = _events.end();
}

void
MidiRegionView::display_model(boost::shared_ptr<MidiModel> model)
{
	_model = model;

	content_connection.disconnect ();
	_model->ContentsChanged.connect (content_connection, invalidator (*this), boost::bind (&MidiRegionView::redisplay_model, this), gui_context());

	clear_events ();

	if (_enable_display) {
		redisplay_model();
	}
}

void
MidiRegionView::start_note_diff_command (string name)
{
	if (!_note_diff_command) {
		_note_diff_command = _model->new_note_diff_command (name);
	}
}

void
MidiRegionView::note_diff_add_note (const boost::shared_ptr<NoteType> note, bool selected, bool show_velocity)
{
	if (_note_diff_command) {
		_note_diff_command->add (note);
	}
	if (selected) {
		_marked_for_selection.insert(note);
	}
	if (show_velocity) {
		_marked_for_velocity.insert(note);
	}
}

void
MidiRegionView::note_diff_remove_note (ArdourCanvas::CanvasNoteEvent* ev)
{
	if (_note_diff_command && ev->note()) {
		_note_diff_command->remove(ev->note());
	}
}

void
MidiRegionView::note_diff_add_change (ArdourCanvas::CanvasNoteEvent* ev,
                                      MidiModel::NoteDiffCommand::Property property,
                                      uint8_t val)
{
	if (_note_diff_command) {
		_note_diff_command->change (ev->note(), property, val);
	}
}

void
MidiRegionView::note_diff_add_change (ArdourCanvas::CanvasNoteEvent* ev,
                                      MidiModel::NoteDiffCommand::Property property,
                                      Evoral::MusicalTime val)
{
	if (_note_diff_command) {
		_note_diff_command->change (ev->note(), property, val);
	}
}

void
MidiRegionView::apply_diff (bool as_subcommand)
{
	bool add_or_remove;

	if (!_note_diff_command) {
		return;
	}

	if ((add_or_remove = _note_diff_command->adds_or_removes())) {
		// 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());
		}
	}

	if (as_subcommand) {
		_model->apply_command_as_subcommand (*trackview.session(), _note_diff_command);
	} else {
		_model->apply_command (*trackview.session(), _note_diff_command);
	}

	_note_diff_command = 0;
	midi_view()->midi_track()->playlist_modified();

	if (add_or_remove) {
		_marked_for_selection.clear();
	}

	_marked_for_velocity.clear();
}

void
MidiRegionView::abort_command()
{
	delete _note_diff_command;
	_note_diff_command = 0;
	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::get_events (Events& e, Evoral::Sequence<Evoral::MusicalTime>::NoteOperator op, uint8_t val, int chan_mask)
{
	MidiModel::Notes notes;
	_model->get_notes (notes, op, val, chan_mask);

	for (MidiModel::Notes::iterator n = notes.begin(); n != notes.end(); ++n) {
		CanvasNoteEvent* cne = find_canvas_note (*n);
		if (cne) {
			e.push_back (cne);
		}
	}
}

void
MidiRegionView::redisplay_model()
{
	// Don't redisplay the model if we're currently recording and displaying that
	if (_active_notes) {
		return;
	}

	if (!_model) {
		return;
	}

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		(*i)->invalidate ();
	}

	MidiModel::ReadLock lock(_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 ();
			}
		}
	}


	/* remove note items that are no longer valid */

	for (Events::iterator i = _events.begin(); i != _events.end(); ) {
		if (!(*i)->valid ()) {

			for (vector<GhostRegion*>::iterator j = ghosts.begin(); j != ghosts.end(); ++j) {
				MidiGhostRegion* gr = dynamic_cast<MidiGhostRegion*> (*j);
				if (gr) {
					gr->remove_note (*i);
				}
			}
			
			delete *i;
			i = _events.erase (i);
			
		} else {
			++i;
		}
	}

	_patch_changes.clear();
	_sys_exes.clear();

	display_sysexes();
	display_patch_changes ();

	_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
MidiRegionView::display_patch_changes ()
{
	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);
	uint16_t chn_mask = mtv->channel_selector().get_selected_channels();

	for (uint8_t i = 0; i < 16; ++i) {
		if (chn_mask & (1<<i)) {
			display_patch_changes_on_channel (i);
		}
		/* TODO gray-out patch instad of not displaying it */
	}
}

void
MidiRegionView::display_patch_changes_on_channel (uint8_t channel)
{
	for (MidiModel::PatchChanges::const_iterator i = _model->patch_changes().begin(); i != _model->patch_changes().end(); ++i) {

		if ((*i)->channel() != channel) {
			continue;
		}

		MIDI::Name::PatchPrimaryKey patch_key ((*i)->bank_msb (), (*i)->bank_lsb (), (*i)->program ());

		boost::shared_ptr<MIDI::Name::Patch> patch =
			MIDI::Name::MidiPatchManager::instance().find_patch(
				_model_name, _custom_device_mode, channel, patch_key);

		if (patch != 0) {
			add_canvas_patch_change (*i, patch->name());
		} else {
			char buf[16];
			/* program and bank numbers are zero-based: convert to one-based: MIDI_BP_ZERO */
			snprintf (buf, 16, "%d %d", (*i)->program() + MIDI_BP_ZERO , (*i)->bank() + MIDI_BP_ZERO);
			add_canvas_patch_change (*i, buf);
		}
	}
}

void
MidiRegionView::display_sysexes()
{
	bool have_periodic_system_messages = false;
	bool display_periodic_messages = true;

	if (!Config->get_never_display_periodic_midi()) {

		for (MidiModel::SysExes::const_iterator i = _model->sysexes().begin(); i != _model->sysexes().end(); ++i) {
			const boost::shared_ptr<const Evoral::MIDIEvent<Evoral::MusicalTime> > mev = 
				boost::static_pointer_cast<const Evoral::MIDIEvent<Evoral::MusicalTime> > (*i);
			
			if (mev) {
				if (mev->is_spp() || mev->is_mtc_quarter() || mev->is_mtc_full()) {
					have_periodic_system_messages = true;
					break;
				}
			}
		}
		
		if (have_periodic_system_messages) {
			double zoom = trackview.editor().get_current_zoom (); // frames per pixel
			
			/* get an approximate value for the number of samples per video frame */
			
			double video_frame = trackview.session()->frame_rate() * (1.0/30);
			
			/* if we are zoomed out beyond than the cutoff (i.e. more
			 * frames per pixel than frames per 4 video frames), don't
			 * show periodic sysex messages.
			 */
			
			if (zoom > (video_frame*4)) {
				display_periodic_messages = false;
			} 
		}
	} else {
		display_periodic_messages = false;
	}

	for (MidiModel::SysExes::const_iterator i = _model->sysexes().begin(); i != _model->sysexes().end(); ++i) {

		const boost::shared_ptr<const Evoral::MIDIEvent<Evoral::MusicalTime> > mev = 
			boost::static_pointer_cast<const Evoral::MIDIEvent<Evoral::MusicalTime> > (*i);

		Evoral::MusicalTime time = (*i)->time();
		assert (time >= 0);

		if (mev) {
			if (mev->is_spp() || mev->is_mtc_quarter() || mev->is_mtc_full()) {
				if (!display_periodic_messages) {
					continue;
				}
			}
		}

		ostringstream str;
		str << hex;
		for (uint32_t b = 0; b < (*i)->size(); ++b) {
			str << int((*i)->buffer()[b]);
			if (b != (*i)->size() -1) {
				str << " ";
			}
		}
		string text = str.str();

		const double x = trackview.editor().frame_to_pixel(source_beats_to_absolute_frames(time));

		double height = midi_stream_view()->contents_height();

		boost::shared_ptr<CanvasSysEx> sysex = boost::shared_ptr<CanvasSysEx>(
			new CanvasSysEx(*this, *_note_group, text, height, x, 1.0));

		// Show unless message is beyond the region bounds
		if (time - _region->start() >= _region->length() || time < _region->start()) {
			sysex->hide();
		} else {
			sysex->show();
		}

		_sys_exes.push_back(sysex);
	}
}

MidiRegionView::~MidiRegionView ()
{
	in_destructor = true;

	trackview.editor().verbose_cursor()->hide ();

	note_delete_connection.disconnect ();

	delete _list_editor;

	RegionViewGoingAway (this); /* EMIT_SIGNAL */

	if (_active_notes) {
		end_write();
	}

	_selection.clear();
	clear_events();

	delete _note_group;
	delete _note_diff_command;
	delete _step_edit_cursor;
	delete _temporary_note_group;
}

void
MidiRegionView::region_resized (const PropertyChange& what_changed)
{
	RegionView::region_resized(what_changed);

	if (what_changed.contains (ARDOUR::Properties::position)) {
		set_duration(_region->length(), 0);
		if (_enable_display) {
			redisplay_model();
		}
	}
}

void
MidiRegionView::reset_width_dependent_items (double pixel_width)
{
	RegionView::reset_width_dependent_items(pixel_width);
	assert(_pixel_width == pixel_width);

	if (_enable_display) {
		redisplay_model();
	}

	move_step_edit_cursor (_step_edit_cursor_position);
	set_step_edit_cursor_width (_step_edit_cursor_width);
}

void
MidiRegionView::set_height (double height)
{
	static const double FUDGE = 2.0;
	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();
	}

	for (PatchChanges::iterator x = _patch_changes.begin(); x != _patch_changes.end(); ++x) {
		(*x)->set_height (midi_stream_view()->contents_height());
	}

	if (_step_edit_cursor) {
		_step_edit_cursor->property_y2() = midi_stream_view()->contents_height();
	}
}


/** Apply the current note range from the stream view
 * by repositioning/hiding notes as necessary
 */
void
MidiRegionView::apply_note_range (uint8_t min, uint8_t max, bool force)
{
	if (!_enable_display) {
		return;
	}

	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;
		boost::shared_ptr<NoteType> note (event->note());

		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)) {

			const double diamond_size = update_hit (chit);

			chit->set_height (diamond_size);
		}
	}
}

GhostRegion*
MidiRegionView::add_ghost (TimeAxisView& tv)
{
	CanvasNote* note;

	double unit_position = _region->position () / samples_per_unit;
	MidiTimeAxisView* mtv = dynamic_cast<MidiTimeAxisView*>(&tv);
	MidiGhostRegion* ghost;

	if (mtv && mtv->midi_view()) {
		/* if ghost is inserted into midi track, use a dedicated midi ghost canvas group
		   to allow having midi notes on top of note lines and waveforms.
		*/
		ghost = new MidiGhostRegion (*mtv->midi_view(), trackview, unit_position);
	} else {
		ghost = new MidiGhostRegion (tv, trackview, unit_position);
	}

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		if ((note = dynamic_cast<CanvasNote*>(*i)) != 0) {
			ghost->add_note(note);
		}
	}

	ghost->set_height ();
	ghost->set_duration (_region->length() / samples_per_unit);
	ghosts.push_back (ghost);

	GhostRegion::CatchDeletion.connect (*this, invalidator (*this), ui_bind (&RegionView::remove_ghost, this, _1), gui_context());

	return ghost;
}


/** Begin tracking note state for successive calls to add_event
 */
void
MidiRegionView::begin_write()
{
	assert(!_active_notes);
	_active_notes = new CanvasNote*[128];
	for (unsigned i=0; i < 128; ++i) {
		_active_notes[i] = 0;
	}
}


/** Destroy note state for add_event
 */
void
MidiRegionView::end_write()
{
	delete[] _active_notes;
	_active_notes = 0;
	_marked_for_selection.clear();
	_marked_for_velocity.clear();
}


/** Resolve an active MIDI note (while recording).
 */
void
MidiRegionView::resolve_note(uint8_t note, double end_time)
{
	if (midi_view()->note_mode() != Sustained) {
		return;
	}

	if (_active_notes && _active_notes[note]) {

		/* XXX is end_time really region-centric? I think so, because
		   this is a new region that we're recording, so source zero is
		   the same as region zero
		*/
		const framepos_t end_time_frames = region_beats_to_region_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] = 0;
	}
}


/** Extend active notes to rightmost edge of region (if length is changed)
 */
void
MidiRegionView::extend_active_notes()
{
	if (!_active_notes) {
		return;
	}

	for (unsigned i=0; i < 128; ++i) {
		if (_active_notes[i]) {
			_active_notes[i]->property_x2() = trackview.editor().frame_to_pixel(_region->length());
		}
	}
}


void
MidiRegionView::play_midi_note(boost::shared_ptr<NoteType> note)
{
	if (_no_sound_notes || !Config->get_sound_midi_notes()) {
		return;
	}

	RouteUI* route_ui = dynamic_cast<RouteUI*> (&trackview);

	if (!route_ui || !route_ui->midi_track()) {
		return;
	}

	NotePlayer* np = new NotePlayer (route_ui->midi_track());
	np->add (note);
	np->play ();
}

void
MidiRegionView::play_midi_chord (vector<boost::shared_ptr<NoteType> > notes)
{
	if (_no_sound_notes || !Config->get_sound_midi_notes()) {
		return;
	}

	RouteUI* route_ui = dynamic_cast<RouteUI*> (&trackview);

	if (!route_ui || !route_ui->midi_track()) {
		return;
	}

	NotePlayer* np = new NotePlayer (route_ui->midi_track());

	for (vector<boost::shared_ptr<NoteType> >::iterator n = notes.begin(); n != notes.end(); ++n) {
		np->add (*n);
	}

	np->play ();
}


bool
MidiRegionView::note_in_region_range (const boost::shared_ptr<NoteType> note, bool& visible) const
{
	const framepos_t note_start_frames = source_beats_to_region_frames (note->time());
	bool outside = (note_start_frames  < 0) || (note_start_frames > _region->last_frame());

	visible = (note->note() >= midi_stream_view()->lowest_note()) &&
		(note->note() <= midi_stream_view()->highest_note());

	return !outside;
}

/** Update a canvas note's size from its model note.
 *  @param ev Canvas note to update.
 *  @param update_ghost_regions true to update the note in any ghost regions that we have, otherwise false.
 */
void
MidiRegionView::update_note (CanvasNote* ev, bool update_ghost_regions)
{
	boost::shared_ptr<NoteType> note = ev->note();
	const double x = trackview.editor().frame_to_pixel (source_beats_to_region_frames (note->time()));
	const double y1 = midi_stream_view()->note_to_y(note->note());

	ev->property_x1() = x;
	ev->property_y1() = y1;

	/* trim note display to not overlap the end of its region */

	if (note->length() > 0) {
		const framepos_t note_end_frames = min (source_beats_to_region_frames (note->end_time()), _region->length());
		ev->property_x2() = trackview.editor().frame_to_pixel (note_end_frames);
	} 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;
	}

	if (update_ghost_regions) {
		for (std::vector<GhostRegion*>::iterator i = ghosts.begin(); i != ghosts.end(); ++i) {
			MidiGhostRegion* gr = dynamic_cast<MidiGhostRegion*> (*i);
			if (gr) {
				gr->update_note (ev);
			}
		}
	}
}

double
MidiRegionView::update_hit (CanvasHit* ev)
{
	boost::shared_ptr<NoteType> note = ev->note();

	const framepos_t note_start_frames = source_beats_to_region_frames(note->time());
	const double x = trackview.editor().frame_to_pixel(note_start_frames);
	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);

	return diamond_size;
}

/** Add a MIDI note to the view (with length).
 *
 * If in sustained mode, notes with length 0 will be considered active
 * notes, and resolve_note should be called when the corresponding note off
 * event arrives, to properly display the note.
 */
void
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);

	//ArdourCanvas::Group* const group = (ArdourCanvas::Group*) get_canvas_group();

	if (midi_view()->note_mode() == Sustained) {

		CanvasNote* ev_rect = new CanvasNote(*this, *_note_group, note);

		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);
			}
		}

	} else if (midi_view()->note_mode() == Percussive) {

		const double diamond_size = midi_stream_view()->note_height() / 2.0;

		CanvasHit* ev_diamond = new CanvasHit (*this, *_note_group, diamond_size, note);

		update_hit (ev_diamond);

		event = ev_diamond;

	} else {
		event = 0;
	}

	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();
		}

		event->on_channel_selection_change(_last_channel_selection);
		_events.push_back(event);

		if (visible) {
			event->show();
		} else {
			event->hide ();
		}
	}

	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);
	MidiStreamView* const view = mtv->midi_view();

	view->update_note_range (note->note());
}

void
MidiRegionView::step_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));

	/* potentially extend region to hold new note */

	framepos_t end_frame = source_beats_to_absolute_frames (new_note->end_time());
	framepos_t region_end = _region->last_frame();

	if (end_frame > region_end) {
		_region->set_length (end_frame - _region->position());
	}

	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);
	MidiStreamView* const view = mtv->midi_view();

	view->update_note_range(new_note->note());

	_marked_for_selection.clear ();
	clear_selection ();

	start_note_diff_command (_("step add"));
	note_diff_add_note (new_note, true, false);
	apply_diff();

	// last_step_edit_note = new_note;
}

void
MidiRegionView::step_sustain (Evoral::MusicalTime beats)
{
	change_note_lengths (false, false, beats, false, true);
}

void
MidiRegionView::add_canvas_patch_change (MidiModel::PatchChangePtr patch, const string& displaytext)
{
	assert (patch->time() >= 0);

	framecnt_t region_frames = source_beats_to_region_frames (patch->time());
	const double x = trackview.editor().frame_to_pixel (region_frames);

	double const height = midi_stream_view()->contents_height();

	boost::shared_ptr<CanvasPatchChange> patch_change = boost::shared_ptr<CanvasPatchChange>(
		new CanvasPatchChange(*this, *_note_group,
		                      displaytext,
		                      height,
		                      x, 1.0,
		                      _model_name,
		                      _custom_device_mode,
		                      patch)
		          );

	// Show unless patch change is beyond the region bounds
	if (region_frames < 0 || region_frames >= _region->length()) {
		patch_change->hide();
	} else {
		patch_change->show();
	}

	_patch_changes.push_back (patch_change);
}

void
MidiRegionView::get_patch_key_at (Evoral::MusicalTime time, uint8_t channel, MIDI::Name::PatchPrimaryKey& key)
{
	MidiModel::PatchChanges::iterator i = _model->patch_change_lower_bound (time);
	while (i != _model->patch_changes().end() && (*i)->channel() != channel) {
		++i;
	}

	if (i != _model->patch_changes().end()) {
		key.msb = (*i)->bank_msb ();
		key.lsb = (*i)->bank_lsb ();
		key.program_number = (*i)->program ();
	} else {
		key.msb = key.lsb = key.program_number = 0;
	}

	assert (key.is_sane());
}


void
MidiRegionView::change_patch_change (CanvasPatchChange& pc, const MIDI::Name::PatchPrimaryKey& new_patch)
{
	MidiModel::PatchChangeDiffCommand* c = _model->new_patch_change_diff_command (_("alter patch change"));

	if (pc.patch()->program() != new_patch.program_number) {
		c->change_program (pc.patch (), new_patch.program_number);
	}

	int const new_bank = (new_patch.msb << 7) | new_patch.lsb;
	if (pc.patch()->bank() != new_bank) {
		c->change_bank (pc.patch (), new_bank);
	}

	_model->apply_command (*trackview.session(), c);

	_patch_changes.clear ();
	display_patch_changes ();
}

void
MidiRegionView::change_patch_change (MidiModel::PatchChangePtr old_change, const Evoral::PatchChange<Evoral::MusicalTime> & new_change)
{
	MidiModel::PatchChangeDiffCommand* c = _model->new_patch_change_diff_command (_("alter patch change"));

	if (old_change->time() != new_change.time()) {
		c->change_time (old_change, new_change.time());
	}

	if (old_change->channel() != new_change.channel()) {
		c->change_channel (old_change, new_change.channel());
	}

	if (old_change->program() != new_change.program()) {
		c->change_program (old_change, new_change.program());
	}

	if (old_change->bank() != new_change.bank()) {
		c->change_bank (old_change, new_change.bank());
	}

	_model->apply_command (*trackview.session(), c);

	_patch_changes.clear ();
	display_patch_changes ();
}

/** Add a patch change to the region.
 *  @param t Time in frames relative to region position
 *  @param patch Patch to add; time and channel are ignored (time is converted from t, and channel comes from
 *  MidiTimeAxisView::get_channel_for_add())
 */
void
MidiRegionView::add_patch_change (framecnt_t t, Evoral::PatchChange<Evoral::MusicalTime> const & patch)
{
	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);

	MidiModel::PatchChangeDiffCommand* c = _model->new_patch_change_diff_command (_("add patch change"));
	c->add (MidiModel::PatchChangePtr (
		        new Evoral::PatchChange<Evoral::MusicalTime> (
			        absolute_frames_to_source_beats (_region->position() + t),
				mtv->get_channel_for_add(), patch.program(), patch.bank()
				)
			)
		);

	_model->apply_command (*trackview.session(), c);

	_patch_changes.clear ();
	display_patch_changes ();
}

void
MidiRegionView::move_patch_change (CanvasPatchChange& pc, Evoral::MusicalTime t)
{
	MidiModel::PatchChangeDiffCommand* c = _model->new_patch_change_diff_command (_("move patch change"));
	c->change_time (pc.patch (), t);
	_model->apply_command (*trackview.session(), c);

	_patch_changes.clear ();
	display_patch_changes ();
}

void
MidiRegionView::delete_patch_change (CanvasPatchChange* pc)
{
	MidiModel::PatchChangeDiffCommand* c = _model->new_patch_change_diff_command (_("delete patch change"));
	c->remove (pc->patch ());
	_model->apply_command (*trackview.session(), c);

	_patch_changes.clear ();
	display_patch_changes ();
}

void
MidiRegionView::previous_patch (CanvasPatchChange& patch)
{
	if (patch.patch()->program() < 127) {
		MIDI::Name::PatchPrimaryKey key;
		get_patch_key_at (patch.patch()->time(), patch.patch()->channel(), key);
		key.program_number++;
		change_patch_change (patch, key);
	}
}

void
MidiRegionView::next_patch (CanvasPatchChange& patch)
{
	if (patch.patch()->program() > 0) {
		MIDI::Name::PatchPrimaryKey key;
		get_patch_key_at (patch.patch()->time(), patch.patch()->channel(), key);
		key.program_number--;
		change_patch_change (patch, key);
	}
}

void
MidiRegionView::previous_bank (CanvasPatchChange& patch)
{
	if (patch.patch()->program() < 127) {
		MIDI::Name::PatchPrimaryKey key;
		get_patch_key_at (patch.patch()->time(), patch.patch()->channel(), key);
		if (key.lsb > 0) {
			key.lsb--;
			change_patch_change (patch, key);
		} else {
			if (key.msb > 0) {
				key.lsb = 127;
				key.msb--;
				change_patch_change (patch, key);
			}
		}
	}
}

void
MidiRegionView::next_bank (CanvasPatchChange& patch)
{
	if (patch.patch()->program() > 0) {
		MIDI::Name::PatchPrimaryKey key;
		get_patch_key_at (patch.patch()->time(), patch.patch()->channel(), key);
		if (key.lsb < 127) {
			key.lsb++;
			change_patch_change (patch, key);
		} else {
			if (key.msb < 127) {
				key.lsb = 0;
				key.msb++;
				change_patch_change (patch, key);
			}
		}
	}
}

void
MidiRegionView::maybe_remove_deleted_note_from_selection (CanvasNoteEvent* cne)
{
	if (_selection.empty()) {
		return;
	}

	_selection.erase (cne);
}

void
MidiRegionView::delete_selection()
{
	if (_selection.empty()) {
		return;
	}

	start_note_diff_command (_("delete selection"));

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		if ((*i)->selected()) {
			_note_diff_command->remove((*i)->note());
		}
	}

	_selection.clear();

	apply_diff ();
}

void
MidiRegionView::delete_note (boost::shared_ptr<NoteType> n)
{
	start_note_diff_command (_("delete note"));
	_note_diff_command->remove (n);
	apply_diff ();

	trackview.editor().verbose_cursor()->hide ();
}

void
MidiRegionView::clear_selection_except (ArdourCanvas::CanvasNoteEvent* ev, bool signal)
{
	bool changed = false;

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
		if ((*i) != ev) {
			Selection::iterator tmp = i;
			++tmp;

			(*i)->set_selected (false);
			(*i)->hide_velocity ();
			_selection.erase (i);
			changed = true;

			i = tmp;
		} else {
			++i;
		}
	}

	/* this does not change the status of this regionview w.r.t the editor
	   selection.
	*/

	if (changed && signal) {
		SelectionCleared (this); /* EMIT SIGNAL */
	}
}

void
MidiRegionView::unique_select(ArdourCanvas::CanvasNoteEvent* ev)
{
	clear_selection_except (ev);

	/* don't bother with checking to see if we should remove this
	   regionview from the editor selection, since we're about to add
	   another note, and thus put/keep this regionview in the editor
	   selection anyway.
	*/

	if (!ev->selected()) {
		add_to_selection (ev);
	}
}

void
MidiRegionView::select_all_notes ()
{
	clear_selection ();

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		add_to_selection (*i);
	}
}

void
MidiRegionView::select_range (framepos_t start, framepos_t end)
{
	clear_selection ();

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		framepos_t t = source_beats_to_absolute_frames((*i)->note()->time());
		if (t >= start && t <= end) {
			add_to_selection (*i);
		}
	}
}

void
MidiRegionView::invert_selection ()
{
	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		if ((*i)->selected()) {
			remove_from_selection(*i);
		} else {
			add_to_selection (*i);
		}
	}
}

void
MidiRegionView::select_matching_notes (uint8_t notenum, uint16_t channel_mask, bool add, bool extend)
{
	uint8_t low_note = 127;
	uint8_t high_note = 0;
	MidiModel::Notes& notes (_model->notes());
	_optimization_iterator = _events.begin();

	if (!add) {
		clear_selection ();
	}

	if (extend && _selection.empty()) {
		extend = false;
	}

	if (extend) {

		/* scan existing selection to get note range */

		for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
			if ((*i)->note()->note() < low_note) {
				low_note = (*i)->note()->note();
			}
			if ((*i)->note()->note() > high_note) {
				high_note = (*i)->note()->note();
			}
		}

		low_note = min (low_note, notenum);
		high_note = max (high_note, notenum);
	}

	_no_sound_notes = true;

	for (MidiModel::Notes::iterator n = notes.begin(); n != notes.end(); ++n) {

		boost::shared_ptr<NoteType> note (*n);
		CanvasNoteEvent* cne;
		bool select = false;

		if (((1 << note->channel()) & channel_mask) != 0) {
			if (extend) {
				if ((note->note() >= low_note && note->note() <= high_note)) {
					select = true;
				}
			} else if (note->note() == notenum) {
				select = true;
			}
		}

		if (select) {
			if ((cne = find_canvas_note (note)) != 0) {
				// extend is false because we've taken care of it,
				// since it extends by time range, not pitch.
				note_selected (cne, add, false);
			}
		}

		add = true; // we need to add all remaining matching notes, even if the passed in value was false (for "set")

	}

	_no_sound_notes = false;
}

void
MidiRegionView::toggle_matching_notes (uint8_t notenum, uint16_t channel_mask)
{
	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;

		if (note->note() == notenum && (((0x0001 << note->channel()) & channel_mask) != 0)) {
			if ((cne = find_canvas_note (note)) != 0) {
				if (cne->selected()) {
					note_deselected (cne);
				} else {
					note_selected (cne, true, false);
				}
			}
		}
	}
}

void
MidiRegionView::note_selected (ArdourCanvas::CanvasNoteEvent* ev, bool add, bool extend)
{
	if (!add) {
		clear_selection_except (ev);
		if (!_selection.empty()) {
			PublicEditor& editor (trackview.editor());
			editor.get_selection().add (this);
		}
	}

	if (!extend) {

		if (!ev->selected()) {
			add_to_selection (ev);
		}

	} else {
		/* find end of latest note selected, select all between that and the start of "ev" */

		Evoral::MusicalTime earliest = Evoral::MaxMusicalTime;
		Evoral::MusicalTime latest = 0;

		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();
			}
		}

		if (ev->note()->end_time() > latest) {
			latest = ev->note()->end_time();
		}

		if (ev->note()->time() < earliest) {
			earliest = ev->note()->time();
		}

		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);
			}

		}
	}
}

void
MidiRegionView::note_deselected(ArdourCanvas::CanvasNoteEvent* ev)
{
	remove_from_selection (ev);
}

void
MidiRegionView::update_drag_selection(double x1, double x2, double y1, double y2, bool extend)
{
	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.

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {

		/* 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() && !extend) {
			// Not inside rectangle
			remove_from_selection (*i);
		}
	}
}

void
MidiRegionView::update_vertical_drag_selection (double y1, double y2, bool extend)
{
	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.

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {

		/* 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.
		*/

		if (((*i)->y1() >= y1 && (*i)->y1() <= y2)) {
			// within y- (note-) range
			if (!(*i)->selected()) {
				add_to_selection (*i);
			}
		} else if ((*i)->selected() && !extend) {
			// Not inside rectangle
			remove_from_selection (*i);
		}
	}
}

void
MidiRegionView::remove_from_selection (CanvasNoteEvent* ev)
{
	Selection::iterator i = _selection.find (ev);

	if (i != _selection.end()) {
		_selection.erase (i);
	}

	ev->set_selected (false);
	ev->hide_velocity ();

	if (_selection.empty()) {
		PublicEditor& editor (trackview.editor());
		editor.get_selection().remove (this);
	}
}

void
MidiRegionView::add_to_selection (CanvasNoteEvent* ev)
{
	bool add_mrv_selection = false;

	if (_selection.empty()) {
		add_mrv_selection = true;
	}

	if (_selection.insert (ev).second) {
		ev->set_selected (true);
		play_midi_note ((ev)->note());
	}

	if (add_mrv_selection) {
		PublicEditor& editor (trackview.editor());
		editor.get_selection().add (this);
	}
}

void
MidiRegionView::move_selection(double dx, double dy, double cumulative_dy)
{
	typedef vector<boost::shared_ptr<NoteType> > PossibleChord;
	PossibleChord to_play;
	Evoral::MusicalTime earliest = Evoral::MaxMusicalTime;

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		if ((*i)->note()->time() < earliest) {
			earliest = (*i)->note()->time();
		}
	}

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		if (Evoral::musical_time_equal ((*i)->note()->time(), earliest)) {
			to_play.push_back ((*i)->note());
		}
		(*i)->move_event(dx, dy);
	}

	if (dy && !_selection.empty() && !_no_sound_notes && Config->get_sound_midi_notes()) {

		if (to_play.size() > 1) {

			PossibleChord shifted;

			for (PossibleChord::iterator n = to_play.begin(); n != to_play.end(); ++n) {
				boost::shared_ptr<NoteType> moved_note (new NoteType (**n));
				moved_note->set_note (moved_note->note() + cumulative_dy);
				shifted.push_back (moved_note);
			}

			play_midi_chord (shifted);

		} else if (!to_play.empty()) {

			boost::shared_ptr<NoteType> moved_note (new NoteType (*to_play.front()));
			moved_note->set_note (moved_note->note() + cumulative_dy);
			play_midi_note (moved_note);
		}
	}
}

void
MidiRegionView::note_dropped(CanvasNoteEvent *, frameoffset_t dt, int8_t dnote)
{
	assert (!_selection.empty());

	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())
	  << " highest note (streamview): " << int(midi_stream_view()->highest_note()) << endl;
	  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 (highest_note_in_selection + dnote > 127) {
		highest_note_difference = highest_note_in_selection - 127;
	}

	start_note_diff_command (_("move notes"));

	for (Selection::iterator i = _selection.begin(); i != _selection.end() ; ++i) {
		
		framepos_t new_frames = source_beats_to_absolute_frames ((*i)->note()->time()) + dt;
		Evoral::MusicalTime new_time = absolute_frames_to_source_beats (new_frames);

		if (new_time < 0) {
			continue;
		}

		note_diff_add_change (*i, MidiModel::NoteDiffCommand::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);

		lowest_note_in_selection  = std::min(lowest_note_in_selection,  new_pitch);
		highest_note_in_selection = std::max(highest_note_in_selection, new_pitch);

		note_diff_add_change (*i, MidiModel::NoteDiffCommand::NoteNumber, new_pitch);
	}

	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()) {
		midi_stream_view()->set_note_range(MidiStreamView::ContentsRange);
	}
}

/** @param x Pixel relative to the region position.
 *  @return Snapped frame relative to the region position.
 */
framepos_t
MidiRegionView::snap_pixel_to_frame(double x)
{
	PublicEditor& editor (trackview.editor());
	return snap_frame_to_frame (editor.pixel_to_frame (x));
}

/** @param x Pixel relative to the region position.
 *  @return Snapped pixel relative to the region position.
 */
double
MidiRegionView::snap_to_pixel(double x)
{
	return (double) trackview.editor().frame_to_pixel(snap_pixel_to_frame(x));
}

double
MidiRegionView::get_position_pixels()
{
	framepos_t region_frame = get_position();
	return trackview.editor().frame_to_pixel(region_frame);
}

double
MidiRegionView::get_end_position_pixels()
{
	framepos_t frame = get_position() + get_duration ();
	return trackview.editor().frame_to_pixel(frame);
}

framepos_t
MidiRegionView::source_beats_to_absolute_frames(double beats) const
{
	/* the time converter will return the frame corresponding to `beats'
	   relative to the start of the source. The start of the source
	   is an implied position given by region->position - region->start
	*/
	const framepos_t source_start = _region->position() - _region->start();
	return  source_start +  _source_relative_time_converter.to (beats);
}

double
MidiRegionView::absolute_frames_to_source_beats(framepos_t frames) const
{
	/* the `frames' argument needs to be converted into a frame count
	   relative to the start of the source before being passed in to the
	   converter.
	*/
	const framepos_t source_start = _region->position() - _region->start();
	return  _source_relative_time_converter.from (frames - source_start);
}

framepos_t
MidiRegionView::region_beats_to_region_frames(double beats) const
{
	return _region_relative_time_converter.to(beats);
}

double
MidiRegionView::region_frames_to_region_beats(framepos_t frames) const
{
	return _region_relative_time_converter.from(frames);
}

void
MidiRegionView::begin_resizing (bool /*at_front*/)
{
	_resize_data.clear();

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		CanvasNote *note = dynamic_cast<CanvasNote *> (*i);

		// only insert CanvasNotes into the map
		if (note) {
			NoteResizeData *resize_data = new NoteResizeData();
			resize_data->canvas_note = note;

			// create a new SimpleRect from the note which will be the resize preview
			SimpleRect *resize_rect = new SimpleRect(
				*_note_group, note->x1(), note->y1(), note->x2(), note->y2());

			// calculate the colors: get the color settings
			uint32_t fill_color = UINT_RGBA_CHANGE_A(
				ARDOUR_UI::config()->canvasvar_MidiNoteSelected.get(),
				128);

			// make the resize preview notes more transparent and bright
			fill_color = UINT_INTERPOLATE(fill_color, 0xFFFFFF40, 0.5);

			// calculate color based on note velocity
			resize_rect->property_fill_color_rgba() = UINT_INTERPOLATE(
				CanvasNoteEvent::meter_style_fill_color(note->note()->velocity(), note->selected()),
				fill_color,
				0.85);

			resize_rect->property_outline_color_rgba() = CanvasNoteEvent::calculate_outline(
				ARDOUR_UI::config()->canvasvar_MidiNoteSelected.get());

			resize_data->resize_rect = resize_rect;
			_resize_data.push_back(resize_data);
		}
	}
}

/** Update resizing notes while user drags.
 * @param primary `primary' note for the drag; ie the one that is used as the reference in non-relative mode.
 * @param at_front which end of the note (true == note on, false == note off)
 * @param delta_x change in mouse position since the start of the drag
 * @param relative true if relative resizing is taking place, false if absolute resizing.  This only makes
 * a difference when multiple notes are being resized; in relative mode, each note's length is changed by the
 * amount of the drag.  In non-relative mode, all selected notes are set to have the same start or end point
 * as the \a primary note.
 */
void
MidiRegionView::update_resizing (ArdourCanvas::CanvasNoteEvent* primary, bool at_front, double delta_x, bool relative)
{
	bool cursor_set = false;

	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;

		if (at_front) {
			if (relative) {
				current_x = canvas_note->x1() + delta_x;
			} else {
				current_x = primary->x1() + delta_x;
			}
		} else {
			if (relative) {
				current_x = canvas_note->x2() + delta_x;
			} else {
				current_x = primary->x2() + delta_x;
			}
		}

		if (at_front) {
			resize_rect->property_x1() = snap_to_pixel(current_x);
			resize_rect->property_x2() = canvas_note->x2();
		} else {
			resize_rect->property_x2() = snap_to_pixel(current_x);
			resize_rect->property_x1() = canvas_note->x1();
		}

		if (!cursor_set) {
			double beats;

			beats = snap_pixel_to_frame (current_x);
			beats = region_frames_to_region_beats (beats);

			double len;

			if (at_front) {
				if (beats < canvas_note->note()->end_time()) {
					len = canvas_note->note()->time() - beats;
					len += canvas_note->note()->length();
				} else {
					len = 0;
				}
			} else {
				if (beats >= canvas_note->note()->time()) {
					len = beats - canvas_note->note()->time();
				} else {
					len = 0;
				}
			}

			char buf[16];
			snprintf (buf, sizeof (buf), "%.3g beats", len);
			show_verbose_cursor (buf, 0, 0);

			cursor_set = true;
		}

	}
}


/** Finish resizing notes when the user releases the mouse button.
 *  Parameters the same as for \a update_resizing().
 */
void
MidiRegionView::commit_resizing (ArdourCanvas::CanvasNoteEvent* primary, bool at_front, double delta_x, bool relative)
{
	start_note_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;

		/* Get the new x position for this resize, which is in pixels relative
		 * to the region position.
		 */
		
		double current_x;

		if (at_front) {
			if (relative) {
				current_x = canvas_note->x1() + delta_x;
			} else {
				current_x = primary->x1() + delta_x;
			}
		} else {
			if (relative) {
				current_x = canvas_note->x2() + delta_x;
			} else {
				current_x = primary->x2() + delta_x;
			}
		}

		/* Convert that to a frame within the source */
		current_x = snap_pixel_to_frame (current_x) + _region->start ();

		/* and then to beats */
		current_x = region_frames_to_region_beats (current_x);

		if (at_front && current_x < canvas_note->note()->end_time()) {
			note_diff_add_change (canvas_note, MidiModel::NoteDiffCommand::StartTime, current_x);

			double len = canvas_note->note()->time() - current_x;
			len += canvas_note->note()->length();

			if (len > 0) {
				/* XXX convert to beats */
				note_diff_add_change (canvas_note, MidiModel::NoteDiffCommand::Length, len);
			}
		}

		if (!at_front) {
			double len = current_x - canvas_note->note()->time();

			if (len > 0) {
				/* XXX convert to beats */
				note_diff_add_change (canvas_note, MidiModel::NoteDiffCommand::Length, len);
			}
		}

		delete resize_rect;
		delete (*i);
	}

	_resize_data.clear();
	apply_diff();
}

void
MidiRegionView::abort_resizing ()
{
	for (std::vector<NoteResizeData *>::iterator i = _resize_data.begin(); i != _resize_data.end(); ++i) {
		delete (*i)->resize_rect;
		delete *i;
	}

	_resize_data.clear ();
}

void
MidiRegionView::change_note_velocity(CanvasNoteEvent* event, int8_t velocity, bool relative)
{
	uint8_t new_velocity;

	if (relative) {
		new_velocity = event->note()->velocity() + velocity;
		clamp_to_0_127(new_velocity);
	} else {
		new_velocity = velocity;
	}

	event->set_selected (event->selected()); // change color

	note_diff_add_change (event, MidiModel::NoteDiffCommand::Velocity, new_velocity);
}

void
MidiRegionView::change_note_note (CanvasNoteEvent* event, int8_t note, bool relative)
{
	uint8_t new_note;

	if (relative) {
		new_note = event->note()->note() + note;
	} else {
		new_note = note;
	}

	clamp_to_0_127 (new_note);
	note_diff_add_change (event, MidiModel::NoteDiffCommand::NoteNumber, new_note);
}

void
MidiRegionView::trim_note (CanvasNoteEvent* event, Evoral::MusicalTime front_delta, Evoral::MusicalTime end_delta)
{
	bool change_start = false;
	bool change_length = false;
	Evoral::MusicalTime new_start = 0;
	Evoral::MusicalTime new_length = 0;

	/* NOTE: the semantics of the two delta arguments are slightly subtle:

	   front_delta: if positive - move the start of the note later in time (shortening it)
	   if negative - move the start of the note earlier in time (lengthening it)

	   end_delta:   if positive - move the end of the note later in time (lengthening it)
	   if negative - move the end of the note earlier in time (shortening it)
	*/

	if (front_delta) {
		if (front_delta < 0) {

			if (event->note()->time() < -front_delta) {
				new_start = 0;
			} else {
				new_start = event->note()->time() + front_delta; // moves earlier
			}

			/* start moved toward zero, so move the end point out to where it used to be.
			   Note that front_delta is negative, so this increases the length.
			*/

			new_length = event->note()->length() - front_delta;
			change_start = true;
			change_length = true;

		} 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;
				change_start = true;
				change_length = true;
			}
		}

	}

	if (end_delta) {
		bool can_change = true;
		if (end_delta < 0) {
			if (event->note()->length() < -end_delta) {
				can_change = false;
			}
		}

		if (can_change) {
			new_length = event->note()->length() + end_delta;
			change_length = true;
		}
	}

	if (change_start) {
		note_diff_add_change (event, MidiModel::NoteDiffCommand::StartTime, new_start);
	}

	if (change_length) {
		note_diff_add_change (event, MidiModel::NoteDiffCommand::Length, new_length);
	}
}

void
MidiRegionView::change_note_channel (CanvasNoteEvent* event, int8_t chn, bool relative)
{
	uint8_t new_channel;

	if (relative) {
		if (chn < 0.0) {
			if (event->note()->channel() < -chn) {
				new_channel = 0;
			} else {
				new_channel = event->note()->channel() + chn;
			}
		} else {
			new_channel = event->note()->channel() + chn;
		}
	} else {
		new_channel = (uint8_t) chn;
	}

	note_diff_add_change (event, MidiModel::NoteDiffCommand::Channel, new_channel);
}

void
MidiRegionView::change_note_time (CanvasNoteEvent* event, Evoral::MusicalTime delta, bool relative)
{
	Evoral::MusicalTime new_time;

	if (relative) {
		if (delta < 0.0) {
			if (event->note()->time() < -delta) {
				new_time = 0;
			} else {
				new_time = event->note()->time() + delta;
			}
		} else {
			new_time = event->note()->time() + delta;
		}
	} else {
		new_time = delta;
	}

	note_diff_add_change (event, MidiModel::NoteDiffCommand::StartTime, new_time);
}

void
MidiRegionView::change_note_length (CanvasNoteEvent* event, Evoral::MusicalTime t)
{
	note_diff_add_change (event, MidiModel::NoteDiffCommand::Length, t);
}

void
MidiRegionView::change_velocities (bool up, bool fine, bool allow_smush)
{
	int8_t delta;

	if (_selection.empty()) {
		return;
	}

	if (fine) {
		delta = 1;
	} else {
		delta = 10;
	}

	if (!up) {
		delta = -delta;
	}

	if (!allow_smush) {
		for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
			if ((*i)->note()->velocity() + delta == 0 || (*i)->note()->velocity() + delta == 127) {
				return;
			}
		}
	}

	start_note_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_diff();

	if (!_selection.empty()) {
		char buf[24];
		snprintf (buf, sizeof (buf), "Vel %d",
		          (int) (*_selection.begin())->note()->velocity());
		show_verbose_cursor (buf, 10, 10);
	}
}


void
MidiRegionView::transpose (bool up, bool fine, bool allow_smush)
{
	if (_selection.empty()) {
		return;
	}

	int8_t delta;

	if (fine) {
		delta = 1;
	} else {
		delta = 12;
	}

	if (!up) {
		delta = -delta;
	}

	if (!allow_smush) {
		for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
			if (!up) {
				if ((int8_t) (*i)->note()->note() + delta <= 0) {
					return;
				}
			} else {
				if ((int8_t) (*i)->note()->note() + delta > 127) {
					return;
				}
			}
		}
	}

	start_note_diff_command (_("transpose"));

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
		Selection::iterator next = i;
		++next;
		change_note_note (*i, delta, true);
		i = next;
	}

	apply_diff ();
}

void
MidiRegionView::change_note_lengths (bool fine, bool shorter, Evoral::MusicalTime delta, bool start, bool end)
{
	if (delta == 0.0) {
		if (fine) {
			delta = 1.0/128.0;
		} else {
			/* grab the current grid distance */
			bool success;
			delta = trackview.editor().get_grid_type_as_beats (success, _region->position());
			if (!success) {
				/* XXX cannot get grid type as beats ... should always be possible ... FIX ME */
				cerr << "Grid type not available as beats - TO BE FIXED\n";
				return;
			}
		}
	}

	if (shorter) {
		delta = -delta;
	}

	start_note_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));
		i = next;
	}

	apply_diff ();

}

void
MidiRegionView::nudge_notes (bool forward)
{
	if (_selection.empty()) {
		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
	   into a vector and sort before using the first one.
	*/

	framepos_t ref_point = source_beats_to_absolute_frames ((*(_selection.begin()))->note()->time());
	framepos_t unused;
	framepos_t distance;

	if (trackview.editor().snap_mode() == Editing::SnapOff) {

		/* grid is off - use nudge distance */

		distance = trackview.editor().get_nudge_distance (ref_point, unused);

	} else {

		/* use grid */

		framepos_t next_pos = ref_point;

		if (forward) {
			if (max_framepos - 1 < next_pos) {
				next_pos += 1;
			}
		} else {
			if (next_pos == 0) {
				return;
			}
			next_pos -= 1;
		}

		trackview.editor().snap_to (next_pos, (forward ? 1 : -1), false);
		distance = ref_point - next_pos;
	}

	if (distance == 0) {
		return;
	}

	Evoral::MusicalTime delta = region_frames_to_region_beats (fabs (distance));

	if (!forward) {
		delta = -delta;
	}

	start_note_diff_command (_("nudge"));

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ) {
		Selection::iterator next = i;
		++next;
		change_note_time (*i, delta, true);
		i = next;
	}

	apply_diff ();
}

void
MidiRegionView::change_channel(uint8_t channel)
{
	start_note_diff_command(_("change channel"));
	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		note_diff_add_change (*i, MidiModel::NoteDiffCommand::Channel, channel);
	}

	apply_diff();
}


void
MidiRegionView::note_entered(ArdourCanvas::CanvasNoteEvent* ev)
{
	Editor* editor = dynamic_cast<Editor*>(&trackview.editor());

	pre_enter_cursor = editor->get_canvas_cursor ();

	if (_mouse_state == SelectTouchDragging) {
		note_selected (ev, true);
	}

	show_verbose_cursor (ev->note ());
}

void
MidiRegionView::note_left (ArdourCanvas::CanvasNoteEvent*)
{
	Editor* editor = dynamic_cast<Editor*>(&trackview.editor());

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		(*i)->hide_velocity ();
	}

	editor->verbose_cursor()->hide ();

	if (pre_enter_cursor) {
		editor->set_canvas_cursor (pre_enter_cursor);
		pre_enter_cursor = 0;
	}
}

void
MidiRegionView::patch_entered (ArdourCanvas::CanvasPatchChange* ev)
{
	ostringstream s;
	/* XXX should get patch name if we can */
	s << _("Bank:") << (ev->patch()->bank() + MIDI_BP_ZERO) << '\n' << _("Program:") << ((int) ev->patch()->program()) + MIDI_BP_ZERO << '\n' << _("Channel:") << ((int) ev->patch()->channel() + 1);
	show_verbose_cursor (s.str(), 10, 20);
}

void
MidiRegionView::patch_left (ArdourCanvas::CanvasPatchChange *)
{
	trackview.editor().verbose_cursor()->hide ();
}

void
MidiRegionView::note_mouse_position (float x_fraction, float /*y_fraction*/, bool can_set_cursor)
{
	Editor* editor = dynamic_cast<Editor*>(&trackview.editor());
	Editing::MouseMode mm = editor->current_mouse_mode();
	bool trimmable = (mm == MouseObject || mm == MouseTimeFX || mm == MouseDraw);

	if (trimmable && x_fraction > 0.0 && x_fraction < 0.2) {
		editor->set_canvas_cursor (editor->cursors()->left_side_trim);
	} else if (trimmable && x_fraction >= 0.8 && x_fraction < 1.0) {
		editor->set_canvas_cursor (editor->cursors()->right_side_trim);
	} else {
		if (pre_enter_cursor && can_set_cursor) {
			editor->set_canvas_cursor (pre_enter_cursor);
		}
	}
}

void
MidiRegionView::set_frame_color()
{
	uint32_t f;

	TimeAxisViewItem::set_frame_color ();

	if (!frame) {
		return;
	}

	if (_selected) {
		f = ARDOUR_UI::config()->canvasvar_SelectedFrameBase.get();
	} else if (high_enough_for_name) {
		f= ARDOUR_UI::config()->canvasvar_MidiFrameBase.get();
	} else {
		f = fill_color;
	}

	if (!rect_visible) {
		f = UINT_RGBA_CHANGE_A (f, 0);
	}

	frame->property_fill_color_rgba() = f;
}

void
MidiRegionView::midi_channel_mode_changed(ChannelMode mode, uint16_t mask)
{
	switch (mode) {
	case AllChannels:
	case FilterChannels:
		_force_channel = -1;
		break;
	case ForceChannel:
		_force_channel = mask;
		mask = 0xFFFF; // Show all notes as active (below)
	};

	// Update notes for selection
	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		(*i)->on_channel_selection_change(mask);
	}

	_last_channel_selection = mask;

	_patch_changes.clear ();
	display_patch_changes ();
}

void
MidiRegionView::midi_patch_settings_changed(std::string model, std::string custom_device_mode)
{
	_model_name         = model;
	_custom_device_mode = custom_device_mode;
	redisplay_model();
}

void
MidiRegionView::cut_copy_clear (Editing::CutCopyOp op)
{
	if (_selection.empty()) {
		return;
	}

	PublicEditor& editor (trackview.editor());

	switch (op) {
	case Delete:
		/* XXX what to do ? */
		break;
	case Cut:
	case Copy:
		editor.get_cut_buffer().add (selection_as_cut_buffer());
		break;
	default:
		break;
	}

	if (op != Copy) {

		start_note_diff_command();

		for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
			switch (op) {
			case Copy:
				break;
			case Delete:
			case Cut:
			case Clear:
				note_diff_remove_note (*i);
				break;
			}
		}

		apply_diff();
	}
}

MidiCutBuffer*
MidiRegionView::selection_as_cut_buffer () const
{
	Notes notes;

	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
		NoteType* n = (*i)->note().get();
		notes.insert (boost::shared_ptr<NoteType> (new NoteType (*n)));
	}

	MidiCutBuffer* cb = new MidiCutBuffer (trackview.session());
	cb->set (notes);

	return cb;
}

/** This method handles undo */
void
MidiRegionView::paste (framepos_t pos, float times, const MidiCutBuffer& mcb)
{
	if (mcb.empty()) {
		return;
	}

	DEBUG_TRACE (DEBUG::CutNPaste, string_compose ("MIDI paste @ %1 times %2\n", pos, times));

	trackview.session()->begin_reversible_command (_("paste"));

	start_note_diff_command (_("paste"));

	Evoral::MusicalTime beat_delta;
	Evoral::MusicalTime paste_pos_beats;
	Evoral::MusicalTime duration;
	Evoral::MusicalTime end_point = 0;

	duration = (*mcb.notes().rbegin())->end_time() - (*mcb.notes().begin())->time();
	paste_pos_beats = region_frames_to_region_beats (pos - _region->position());
	beat_delta = (*mcb.notes().begin())->time() - paste_pos_beats;
	paste_pos_beats = 0;

	DEBUG_TRACE (DEBUG::CutNPaste, string_compose ("Paste data spans from %1 to %2 (%3) ; paste pos beats = %4 (based on %5 - %6 ; beat delta = %7\n",
	                                               (*mcb.notes().begin())->time(),
	                                               (*mcb.notes().rbegin())->end_time(),
	                                               duration, pos, _region->position(),
	                                               paste_pos_beats, beat_delta));

	clear_selection ();

	for (int n = 0; n < (int) times; ++n) {

		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);

			/* make all newly added notes selected */

			note_diff_add_note (copied_note, true);
			end_point = copied_note->end_time();
		}

		paste_pos_beats += duration;
	}

	/* if we pasted past the current end of the region, extend the region */

	framepos_t end_frame = source_beats_to_absolute_frames (end_point);
	framepos_t region_end = _region->position() + _region->length() - 1;

	if (end_frame > region_end) {

		DEBUG_TRACE (DEBUG::CutNPaste, string_compose ("Paste extended region from %1 to %2\n", region_end, end_frame));

		_region->clear_changes ();
		_region->set_length (end_frame - _region->position());
		trackview.session()->add_command (new StatefulDiffCommand (_region));
	}

	apply_diff (true);

	trackview.session()->commit_reversible_command ();
}

struct EventNoteTimeEarlyFirstComparator {
	bool operator() (CanvasNoteEvent* a, CanvasNoteEvent* b) {
		return a->note()->time() < b->note()->time();
	}
};

void
MidiRegionView::time_sort_events ()
{
	if (!_sort_needed) {
		return;
	}

	EventNoteTimeEarlyFirstComparator cmp;
	_events.sort (cmp);

	_sort_needed = false;
}

void
MidiRegionView::goto_next_note (bool add_to_selection)
{
	bool use_next = false;

	if (_events.back()->selected()) {
		return;
	}

	time_sort_events ();

	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);
	uint16_t const channel_mask = mtv->channel_selector().get_selected_channels ();

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		if ((*i)->selected()) {
			use_next = true;
			continue;
		} else if (use_next) {
			if (channel_mask & (1 << (*i)->note()->channel())) {
				if (!add_to_selection) {
					unique_select (*i);
				} else {
					note_selected (*i, true, false);
				}
				return;
			}
		}
	}

	/* use the first one */

	if (!_events.empty() && (channel_mask & (1 << _events.front()->note()->channel ()))) {
		unique_select (_events.front());
	}
}

void
MidiRegionView::goto_previous_note (bool add_to_selection)
{
	bool use_next = false;

	if (_events.front()->selected()) {
		return;
	}

	time_sort_events ();

	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);
	uint16_t const channel_mask = mtv->channel_selector().get_selected_channels ();

	for (Events::reverse_iterator i = _events.rbegin(); i != _events.rend(); ++i) {
		if ((*i)->selected()) {
			use_next = true;
			continue;
		} else if (use_next) {
			if (channel_mask & (1 << (*i)->note()->channel())) {
				if (!add_to_selection) {
					unique_select (*i);
				} else {
					note_selected (*i, true, false);
				}
				return;
			}
		}
	}

	/* use the last one */

	if (!_events.empty() && (channel_mask & (1 << (*_events.rbegin())->note()->channel ()))) {
		unique_select (*(_events.rbegin()));
	}
}

void
MidiRegionView::selection_as_notelist (Notes& selected, bool allow_all_if_none_selected)
{
	bool had_selected = false;

	time_sort_events ();

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		if ((*i)->selected()) {
			selected.insert ((*i)->note());
			had_selected = true;
		}
	}

	if (allow_all_if_none_selected && !had_selected) {
		for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
			selected.insert ((*i)->note());
		}
	}
}

void
MidiRegionView::update_ghost_note (double x, double y)
{
	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);

	_last_ghost_x = x;
	_last_ghost_y = y;

	_note_group->w2i (x, y);

	PublicEditor& editor = trackview.editor ();
	
	framepos_t const unsnapped_frame = editor.pixel_to_frame (x);
	framecnt_t grid_frames;
	framepos_t const f = snap_frame_to_grid_underneath (unsnapped_frame, grid_frames);

	/* use region_frames... because we are converting a delta within the region
	*/
	 
	bool success;
	double length = editor.get_grid_type_as_beats (success, unsnapped_frame);

	if (!success) {
		length = 1;
	}

	/* note that this sets the time of the ghost note in beats relative to
	   the start of the source; that is how all note times are stored.
	*/
	_ghost_note->note()->set_time (absolute_frames_to_source_beats (f + _region->position ()));
	_ghost_note->note()->set_length (length);
	_ghost_note->note()->set_note (midi_stream_view()->y_to_note (y));
	_ghost_note->note()->set_channel (mtv->get_channel_for_add ());

	/* the ghost note does not appear in ghost regions, so pass false in here */
	update_note (_ghost_note, false);

	show_verbose_cursor (_ghost_note->note ());
}

void
MidiRegionView::create_ghost_note (double x, double y)
{
	remove_ghost_note ();

	boost::shared_ptr<NoteType> g (new NoteType);
	_ghost_note = new NoEventCanvasNote (*this, *_note_group, g);
	_ghost_note->property_outline_color_rgba() = 0x000000aa;
	update_ghost_note (x, y);
	_ghost_note->show ();

	_last_ghost_x = x;
	_last_ghost_y = y;

	show_verbose_cursor (_ghost_note->note ());
}

void
MidiRegionView::snap_changed ()
{
	if (!_ghost_note) {
		return;
	}

	create_ghost_note (_last_ghost_x, _last_ghost_y);
}

void
MidiRegionView::drop_down_keys ()
{
	_mouse_state = None;
}

void
MidiRegionView::maybe_select_by_position (GdkEventButton* ev, double /*x*/, double y)
{
	double note = midi_stream_view()->y_to_note(y);
	Events e;
	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);

	uint16_t chn_mask = mtv->channel_selector().get_selected_channels();

	if (Keyboard::modifier_state_equals (ev->state, Keyboard::TertiaryModifier)) {
		get_events (e, Evoral::Sequence<Evoral::MusicalTime>::PitchGreaterThanOrEqual, (uint8_t) floor (note), chn_mask);
	} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
		get_events (e, Evoral::Sequence<Evoral::MusicalTime>::PitchLessThanOrEqual, (uint8_t) floor (note), chn_mask);
	} else {
		return;
	}

	bool add_mrv_selection = false;

	if (_selection.empty()) {
		add_mrv_selection = true;
	}

	for (Events::iterator i = e.begin(); i != e.end(); ++i) {
		if (_selection.insert (*i).second) {
			(*i)->set_selected (true);
		}
	}

	if (add_mrv_selection) {
		PublicEditor& editor (trackview.editor());
		editor.get_selection().add (this);
	}
}

void
MidiRegionView::color_handler ()
{
	RegionView::color_handler ();

	for (Events::iterator i = _events.begin(); i != _events.end(); ++i) {
		(*i)->set_selected ((*i)->selected()); // will change color
	}

	/* XXX probably more to do here */
}

void
MidiRegionView::enable_display (bool yn)
{
	RegionView::enable_display (yn);
	if (yn) {
		redisplay_model ();
	}
}

void
MidiRegionView::show_step_edit_cursor (Evoral::MusicalTime pos)
{
	if (_step_edit_cursor == 0) {
		ArdourCanvas::Group* const group = (ArdourCanvas::Group*)get_canvas_group();

		_step_edit_cursor = new ArdourCanvas::SimpleRect (*group);
		_step_edit_cursor->property_y1() = 0;
		_step_edit_cursor->property_y2() = midi_stream_view()->contents_height();
		_step_edit_cursor->property_fill_color_rgba() = RGBA_TO_UINT (45,0,0,90);
		_step_edit_cursor->property_outline_color_rgba() = RGBA_TO_UINT (85,0,0,90);
	}

	move_step_edit_cursor (pos);
	_step_edit_cursor->show ();
}

void
MidiRegionView::move_step_edit_cursor (Evoral::MusicalTime pos)
{
	_step_edit_cursor_position = pos;

	if (_step_edit_cursor) {
		double pixel = trackview.editor().frame_to_pixel (region_beats_to_region_frames (pos));
		_step_edit_cursor->property_x1() = pixel;
		set_step_edit_cursor_width (_step_edit_cursor_width);
	}
}

void
MidiRegionView::hide_step_edit_cursor ()
{
	if (_step_edit_cursor) {
		_step_edit_cursor->hide ();
	}
}

void
MidiRegionView::set_step_edit_cursor_width (Evoral::MusicalTime beats)
{
	_step_edit_cursor_width = beats;

	if (_step_edit_cursor) {
		_step_edit_cursor->property_x2() = _step_edit_cursor->property_x1() + trackview.editor().frame_to_pixel (region_beats_to_region_frames (beats));
	}
}

/** Called when a diskstream on our track has received some data.  Update the view, if applicable.
 *  @param w Source that the data will end up in.
 */
void
MidiRegionView::data_recorded (boost::weak_ptr<MidiSource> w)
{
	if (!_active_notes) {
		/* we aren't actively being recorded to */
		return;
	}

	boost::shared_ptr<MidiSource> src = w.lock ();
	if (!src || src != midi_region()->midi_source()) {
		/* recorded data was not destined for our source */
		return;
	}

	MidiTimeAxisView* mtv = dynamic_cast<MidiTimeAxisView*> (&trackview);

	boost::shared_ptr<MidiBuffer> buf = mtv->midi_track()->get_gui_feed_buffer ();

	BeatsFramesConverter converter (trackview.session()->tempo_map(), mtv->midi_track()->get_capture_start_frame (0));

	framepos_t back = max_framepos;

	for (MidiBuffer::iterator i = buf->begin(); i != buf->end(); ++i) {
		Evoral::MIDIEvent<MidiBuffer::TimeType> const ev (*i, false);
		assert (ev.buffer ());

		/* ev.time() is in session frames, so (ev.time() - converter.origin_b()) is
		   frames from the start of the source, and so time_beats is in terms of the
		   source.
		*/

		Evoral::MusicalTime const time_beats = converter.from (ev.time () - converter.origin_b ());

		if (ev.type() == MIDI_CMD_NOTE_ON) {

			boost::shared_ptr<NoteType> note (
				new NoteType (ev.channel(), time_beats, 0, ev.note(), ev.velocity())
			                                  );

			add_note (note, true);

			/* fix up our note range */
			if (ev.note() < _current_range_min) {
				midi_stream_view()->apply_note_range (ev.note(), _current_range_max, true);
			} else if (ev.note() > _current_range_max) {
				midi_stream_view()->apply_note_range (_current_range_min, ev.note(), true);
			}

		} else if (ev.type() == MIDI_CMD_NOTE_OFF) {
			resolve_note (ev.note (), time_beats);
		}

		back = ev.time ();
	}

	midi_stream_view()->check_record_layers (region(), back);
}

void
MidiRegionView::trim_front_starting ()
{
	/* Reparent the note group to the region view's parent, so that it doesn't change
	   when the region view is trimmed.
	*/
	_temporary_note_group = new ArdourCanvas::Group (*group->property_parent ());
	_temporary_note_group->move (group->property_x(), group->property_y());
	_note_group->reparent (*_temporary_note_group);
}

void
MidiRegionView::trim_front_ending ()
{
	_note_group->reparent (*group);
	delete _temporary_note_group;
	_temporary_note_group = 0;

	if (_region->start() < 0) {
		/* Trim drag made start time -ve; fix this */
		midi_region()->fix_negative_start ();
	}
}

void
MidiRegionView::edit_patch_change (ArdourCanvas::CanvasPatchChange* pc)
{
	PatchChangeDialog d (&_source_relative_time_converter, trackview.session(), *pc->patch (), Gtk::Stock::APPLY);
	if (d.run () != Gtk::RESPONSE_ACCEPT) {
		return;
	}

	change_patch_change (pc->patch(), d.patch ());
}


void
MidiRegionView::show_verbose_cursor (boost::shared_ptr<NoteType> n) const
{
	char buf[24];
	snprintf (buf, sizeof (buf), "%s (%d) Chn %d\nVel %d",
	          Evoral::midi_note_name (n->note()).c_str(),
	          (int) n->note (),
	          (int) n->channel() + 1,
	          (int) n->velocity());

	show_verbose_cursor (buf, 10, 20);
}

void
MidiRegionView::show_verbose_cursor (string const & text, double xoffset, double yoffset) const
{
	double wx, wy;

	trackview.editor().get_pointer_position (wx, wy);

	wx += xoffset;
	wy += yoffset;

	/* Flip the cursor above the mouse pointer if it would overlap the bottom of the canvas */

	double x1, y1, x2, y2;
	trackview.editor().verbose_cursor()->canvas_item()->get_bounds (x1, y1, x2, y2);

	if ((wy + y2 - y1) > trackview.editor().canvas_height()) {
		wy -= (y2 - y1) + 2 * yoffset;
	}

	trackview.editor().verbose_cursor()->set (text, wx, wy);
	trackview.editor().verbose_cursor()->show ();
}

/** @param p A session framepos.
 *  @param grid_frames Filled in with the number of frames that a grid interval is at p.
 *  @return p snapped to the grid subdivision underneath it.
 */
framepos_t
MidiRegionView::snap_frame_to_grid_underneath (framepos_t p, framecnt_t& grid_frames) const
{
	PublicEditor& editor = trackview.editor ();
	
	bool success;
	Evoral::MusicalTime grid_beats = editor.get_grid_type_as_beats (success, p);

	if (!success) {
		grid_beats = 1;
	}
	
	grid_frames = region_beats_to_region_frames (grid_beats);

	/* Hack so that we always snap to the note that we are over, instead of snapping
	   to the next one if we're more than halfway through the one we're over.
	*/
	if (editor.snap_mode() == SnapNormal && p >= grid_frames / 2) {
		p -= grid_frames / 2;
	}

	return snap_frame_to_frame (p);
}

/** Called when the selection has been cleared in any MidiRegionView.
 *  @param rv MidiRegionView that the selection was cleared in.
 */
void
MidiRegionView::selection_cleared (MidiRegionView* rv)
{
	if (rv == this) {
		return;
	}

	/* Clear our selection in sympathy; but don't signal the fact */
	clear_selection (false);
}