livetrax/gtk2_ardour/midi_cue_editor.cc

/*
 * Copyright (C) 2023 Paul Davis <paul@linuxaudiosystems.com>
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "ardour/midi_region.h"
#include "ardour/midi_track.h"
#include "ardour/smf_source.h"

#include "canvas/box.h"
#include "canvas/canvas.h"
#include "canvas/container.h"
#include "canvas/debug.h"
#include "canvas/scroll_group.h"
#include "canvas/rectangle.h"
#include "canvas/widget.h"

#include "gtkmm2ext/actions.h"

#include "widgets/ardour_button.h"

#include "ardour_ui.h"
#include "editor_cursors.h"
#include "editor_drag.h"
#include "gui_thread.h"
#include "keyboard.h"
#include "midi_cue_background.h"
#include "midi_cue_editor.h"
#include "midi_cue_view.h"
#include "note_base.h"
#include "prh.h"
#include "timers.h"
#include "ui_config.h"
#include "velocity_ghost_region.h"
#include "verbose_cursor.h"

#include "pbd/i18n.h"

using namespace ARDOUR;
using namespace ArdourCanvas;
using namespace ArdourWidgets;
using namespace Gtkmm2ext;
using namespace Temporal;

MidiCueEditor::MidiCueEditor()
	: CueEditor (X_("MIDICueEditor"))
	, timebar_height (15.)
	, n_timebars (3)
	, prh (nullptr)
	, bg (nullptr)
	, view (nullptr)
	, bbt_metric (*this)
{
	mouse_mode = Editing::MouseContent;
	autoscroll_vertical_allowed = false;

	bindings = Bindings::get_bindings (editor_name());

	register_actions ();

	build_grid_type_menu ();
	build_draw_midi_menus();

	build_canvas ();
	setup_toolbar ();

	_toolbox.pack_start (viewport(), true, true);

	set_mouse_mode (Editing::MouseContent, true);
}

MidiCueEditor::~MidiCueEditor ()
{
	delete bindings;
}

void
MidiCueEditor::register_actions ()
{
	editor_actions = ActionManager::create_action_group (bindings, editor_name());
	register_mouse_mode_actions ();
	bind_mouse_mode_buttons ();
	register_grid_actions ();
}

ArdourCanvas::GtkCanvasViewport*
MidiCueEditor::get_canvas_viewport() const
{
	return _canvas_viewport;
}

ArdourCanvas::GtkCanvas*
MidiCueEditor::get_canvas() const
{
	return _canvas;
}

bool
MidiCueEditor::canvas_pre_event (GdkEvent* ev)
{
	switch (ev->type) {
	case GDK_ENTER_NOTIFY:
	case GDK_LEAVE_NOTIFY:
		if (canvas_enter_leave (&ev->crossing)) {
			return true;
		}
		break;
	default:
		break;
	}

	return false;
}

void
MidiCueEditor::setup_toolbar ()
{
	Gtk::HBox* mode_box = manage(new Gtk::HBox);
	mode_box->set_border_width (2);
	mode_box->set_spacing(2);

	Gtk::HBox* mouse_mode_box = manage (new Gtk::HBox);
	Gtk::HBox* mouse_mode_hbox = manage (new Gtk::HBox);
	Gtk::VBox* mouse_mode_vbox = manage (new Gtk::VBox);
	Gtk::Alignment* mouse_mode_align = manage (new Gtk::Alignment);

	Glib::RefPtr<Gtk::SizeGroup> mouse_mode_size_group = Gtk::SizeGroup::create (Gtk::SIZE_GROUP_VERTICAL);
	mouse_mode_size_group->add_widget (mouse_draw_button);
	mouse_mode_size_group->add_widget (mouse_content_button);

	mouse_mode_size_group->add_widget (grid_type_selector);
	mouse_mode_size_group->add_widget (draw_length_selector);
	mouse_mode_size_group->add_widget (draw_velocity_selector);
	mouse_mode_size_group->add_widget (draw_channel_selector);
	mouse_mode_size_group->add_widget (snap_mode_button);

	mouse_mode_hbox->set_spacing (2);
	mouse_mode_hbox->pack_start (mouse_draw_button, false, false);
	mouse_mode_hbox->pack_start (mouse_content_button, false, false);

	mouse_mode_vbox->pack_start (*mouse_mode_hbox);

	mouse_mode_align->add (*mouse_mode_vbox);
	mouse_mode_align->set (0.5, 1.0, 0.0, 0.0);

	mouse_mode_box->pack_start (*mouse_mode_align, false, false);

	pack_snap_box ();
	pack_draw_box ();

	Gtk::HBox* _toolbar_inner = manage (new Gtk::HBox);
	Gtk::HBox* _toolbar_outer = manage (new Gtk::HBox);

	_toolbar_inner->pack_start (*mouse_mode_box, false, false);
	_toolbar_inner->pack_start (snap_box, false, false);
	_toolbar_inner->pack_start (grid_box, false, false);
	_toolbar_inner->pack_start (draw_box, false, false);

	_toolbar_outer->pack_start (*_toolbar_inner, true, false);
	_toolbox.pack_start (*_toolbar_outer, false, false);

	Bindings* pr_bindings = Bindings::get_bindings (X_("Pianoroll"));
	_toolbox.set_data (X_("ardour-bindings"), pr_bindings);
}

void
MidiCueEditor::build_canvas ()
{
	_canvas_viewport = new ArdourCanvas::GtkCanvasViewport (horizontal_adjustment, vertical_adjustment);

	_canvas = _canvas_viewport->canvas ();
	_canvas->set_background_color (UIConfiguration::instance().color ("arrange base"));
	_canvas->signal_event().connect (sigc::mem_fun (*this, &MidiCueEditor::canvas_pre_event), false);
	dynamic_cast<ArdourCanvas::GtkCanvas*>(_canvas)->use_nsglview (UIConfiguration::instance().get_nsgl_view_mode () == NSGLHiRes);

	_canvas->PreRender.connect (sigc::mem_fun(*this, &EditingContext::pre_render));

	/* scroll group for items that should not automatically scroll
	 *  (e.g verbose cursor). It shares the canvas coordinate space.
	*/
	no_scroll_group = new ArdourCanvas::Container (_canvas->root());

	h_scroll_group = new ArdourCanvas::ScrollGroup (_canvas->root(), ArdourCanvas::ScrollGroup::ScrollsHorizontally);
	CANVAS_DEBUG_NAME (h_scroll_group, "canvas h scroll");
	_canvas->add_scroller (*h_scroll_group);


	v_scroll_group = new ArdourCanvas::ScrollGroup (_canvas->root(), ArdourCanvas::ScrollGroup::ScrollsVertically);
	CANVAS_DEBUG_NAME (v_scroll_group, "canvas v scroll");
	_canvas->add_scroller (*v_scroll_group);

	hv_scroll_group = new ArdourCanvas::ScrollGroup (_canvas->root(),
	                                                 ArdourCanvas::ScrollGroup::ScrollSensitivity (ArdourCanvas::ScrollGroup::ScrollsVertically|
		                ArdourCanvas::ScrollGroup::ScrollsHorizontally));
	CANVAS_DEBUG_NAME (hv_scroll_group, "cue canvas hv scroll");
	_canvas->add_scroller (*hv_scroll_group);

	cursor_scroll_group = new ArdourCanvas::ScrollGroup (_canvas->root(), ArdourCanvas::ScrollGroup::ScrollsHorizontally);
	CANVAS_DEBUG_NAME (cursor_scroll_group, "cue canvas cursor scroll");
	_canvas->add_scroller (*cursor_scroll_group);

	/*a group to hold global rects like punch/loop indicators */
	global_rect_group = new ArdourCanvas::Container (hv_scroll_group);
	CANVAS_DEBUG_NAME (global_rect_group, "cue global rect group");

        transport_loop_range_rect = new ArdourCanvas::Rectangle (global_rect_group, ArdourCanvas::Rect (0.0, 0.0, 0.0, ArdourCanvas::COORD_MAX));
	CANVAS_DEBUG_NAME (transport_loop_range_rect, "cue loop rect");
	transport_loop_range_rect->hide();

	/*a group to hold time (measure) lines */
	time_line_group = new ArdourCanvas::Container (h_scroll_group);
	CANVAS_DEBUG_NAME (time_line_group, "cue  time line group");

	meter_bar = new ArdourCanvas::Rectangle (time_line_group, ArdourCanvas::Rect (0., 0, ArdourCanvas::COORD_MAX, timebar_height));
	CANVAS_DEBUG_NAME (meter_bar, "Meter Bar");
	meter_bar->set_fill(true);
	meter_bar->set_outline(true);
	meter_bar->set_outline_what(ArdourCanvas::Rectangle::BOTTOM);
	meter_bar->set_fill_color (UIConfiguration::instance().color_mod ("meter bar", "marker bar"));
	meter_bar->set_outline_color (UIConfiguration::instance().color ("marker bar separator"));
	meter_bar->set_outline_what (ArdourCanvas::Rectangle::BOTTOM);

	tempo_bar = new ArdourCanvas::Rectangle (time_line_group, ArdourCanvas::Rect (0.0, timebar_height, ArdourCanvas::COORD_MAX, timebar_height * 2));
	CANVAS_DEBUG_NAME (tempo_bar, "Tempo Bar");
	tempo_bar->set_fill(true);
	tempo_bar->set_outline(true);
	tempo_bar->set_outline_what(ArdourCanvas::Rectangle::BOTTOM);
	tempo_bar->set_fill_color (UIConfiguration::instance().color_mod ("tempo bar", "marker bar"));
	tempo_bar->set_outline_color (UIConfiguration::instance().color ("marker bar separator"));
	meter_bar->set_outline_what (ArdourCanvas::Rectangle::BOTTOM);

	Pango::FontDescription font (UIConfiguration::instance().get_SmallerFont());
	Pango::FontDescription larger_font (UIConfiguration::instance().get_SmallBoldFont());
	bbt_ruler = new ArdourCanvas::Ruler (time_line_group, &bbt_metric, ArdourCanvas::Rect (0, timebar_height * 2, ArdourCanvas::COORD_MAX, timebar_height * 3));
	bbt_ruler->set_font_description (font);
	bbt_ruler->set_second_font_description (larger_font);
	Gtkmm2ext::Color base = UIConfiguration::instance().color ("ruler base");
	Gtkmm2ext::Color text = UIConfiguration::instance().color ("ruler text");
	bbt_ruler->set_fill_color (base);
	bbt_ruler->set_outline_color (text);
	CANVAS_DEBUG_NAME (bbt_ruler, "cue bbt ruler");

	data_group = new ArdourCanvas::Container (hv_scroll_group);
	CANVAS_DEBUG_NAME (data_group, "cue data group");

	bg = new CueMidiBackground (data_group);
	_canvas_viewport->signal_size_allocate().connect (sigc::mem_fun(*this, &MidiCueEditor::canvas_allocate), false);

	// used as rubberband rect
	rubberband_rect = new ArdourCanvas::Rectangle (data_group, ArdourCanvas::Rect (0.0, 0.0, 0.0, 0.0));
	rubberband_rect->hide();
	rubberband_rect->set_outline_color (UIConfiguration::instance().color ("rubber band rect"));
	rubberband_rect->set_fill_color (UIConfiguration::instance().color_mod ("rubber band rect", "selection rect"));
	CANVAS_DEBUG_NAME (rubberband_rect, X_("cue rubberband rect"));

	prh = new ArdourCanvas::PianoRollHeader (v_scroll_group, *bg);

	view = new MidiCueView (nullptr, 0, *data_group, *this, *bg, 0xff0000ff);

	bg->set_view (view);
	prh->set_view (view);

	/* This must be called after prh and bg have had their view set */

	double w, h;
	prh->size_request (w, h);

	_timeline_origin = w;

	prh->set_position (Duple (0., n_timebars * timebar_height));
	data_group->set_position (ArdourCanvas::Duple (_timeline_origin, timebar_height * n_timebars));
	cursor_scroll_group->set_position (ArdourCanvas::Duple (_timeline_origin, timebar_height * n_timebars));
	h_scroll_group->set_position (Duple (_timeline_origin, 0.));

	_verbose_cursor = new VerboseCursor (*this);

	// _playhead_cursor = new EditorCursor (*this, &Editor::canvas_playhead_cursor_event, X_("playhead"));
	_playhead_cursor = new EditorCursor (*this, X_("playhead"));
	_playhead_cursor->set_sensitive (UIConfiguration::instance().get_sensitize_playhead());
	_playhead_cursor->set_color (UIConfiguration::instance().color ("play head"));
	_playhead_cursor->canvas_item().raise_to_top();

	_canvas->set_name ("MidiCueCanvas");
	_canvas->add_events (Gdk::POINTER_MOTION_HINT_MASK | Gdk::SCROLL_MASK | Gdk::KEY_PRESS_MASK | Gdk::KEY_RELEASE_MASK);
	_canvas->set_can_focus ();

	bindings_changed ();
}

void
MidiCueEditor::bindings_changed ()
{
	Bindings* midi_bindings = Bindings::get_bindings (X_("MIDI"));
	Bindings* shared_bindings = Bindings::get_bindings (X_("Editing"));

	_canvas_viewport->set_data (X_("ardour-bindings"), shared_bindings);
	_canvas->set_data (X_("ardour-bindings"), midi_bindings);
}

void
MidiCueEditor::maybe_update ()
{
	if (!_track) {
		return;
	}

	if (_track->rec_enable_control()->get_value()) {
		/* ::data_captured() will handle it */
		return;
	}

	ARDOUR::TriggerPtr trigger = _track->triggerbox()->currently_playing ();

	if (!trigger) {
		_playhead_cursor->set_position (0);
	} else {
		if (trigger->active ()) {
			_playhead_cursor->set_position (trigger->current_pos().samples());
		} else {
			_playhead_cursor->set_position (0);
		}
	}
}

bool
MidiCueEditor::canvas_enter_leave (GdkEventCrossing* ev)
{
	switch (ev->type) {
	case GDK_ENTER_NOTIFY:
		if (ev->detail != GDK_NOTIFY_INFERIOR) {
			_canvas_viewport->canvas()->grab_focus ();
			ActionManager::set_sensitive (_midi_actions, true);
			EditingContext::switch_editing_context (this);
		}
		break;
	case GDK_LEAVE_NOTIFY:
		if (ev->detail != GDK_NOTIFY_INFERIOR) {
			ActionManager::set_sensitive (_midi_actions, false);
			ARDOUR_UI::instance()->reset_focus (_canvas_viewport);
		}
	default:
		break;
	}
	return false;
}

void
MidiCueEditor::canvas_allocate (Gtk::Allocation alloc)
{
	_visible_canvas_width = alloc.get_width();
	_visible_canvas_height = alloc.get_height();

	double timebars = n_timebars * timebar_height;
	bg->set_size (alloc.get_width(), alloc.get_height() - timebars);
	view->set_height (alloc.get_height() - timebars);
	prh->set (ArdourCanvas::Rect (0, 0, prh->x1(), view->midi_context().height()));
}

timepos_t
MidiCueEditor::snap_to_grid (timepos_t const & presnap, Temporal::RoundMode direction, SnapPref gpref) const
{
	/* BBT time only */
	return snap_to_bbt (presnap, direction, gpref);
}

void
MidiCueEditor::snap_to_internal (timepos_t& start, Temporal::RoundMode direction, SnapPref pref, bool ensure_snap) const
{
	UIConfiguration const& uic (UIConfiguration::instance ());
	const timepos_t presnap = start;


	timepos_t dist = timepos_t::max (start.time_domain()); // this records the distance of the best snap result we've found so far
	timepos_t best = timepos_t::max (start.time_domain()); // this records the best snap-result we've found so far

	timepos_t pre (presnap);
	timepos_t post (snap_to_grid (pre, direction, pref));

	check_best_snap (presnap, post, dist, best);

	if (timepos_t::max (start.time_domain()) == best) {
		return;
	}

	/* now check "magnetic" state: is the grid within reasonable on-screen distance to trigger a snap?
	 * this also helps to avoid snapping to somewhere the user can't see.  (i.e.: I clicked on a region and it disappeared!!)
	 * ToDo: Perhaps this should only occur if EditPointMouse?
	 */
	samplecnt_t snap_threshold_s = pixel_to_sample (uic.get_snap_threshold ());

	if (!ensure_snap && ::llabs (best.distance (presnap).samples()) > snap_threshold_s) {
		return;
	}

	start = best;
}

void
MidiCueEditor::set_samples_per_pixel (samplecnt_t spp)
{
	CueEditor::set_samples_per_pixel (spp);

	if (view) {
		view->set_samples_per_pixel (spp);
	}

	bbt_ruler->set_range (0, current_page_samples());
	compute_bbt_ruler_scale (0, current_page_samples());
	bbt_metric.units_per_pixel = spp;
}

samplecnt_t
MidiCueEditor::current_page_samples() const
{
	return (samplecnt_t) _visible_canvas_width* samples_per_pixel;
}

bool
MidiCueEditor::canvas_control_point_event (GdkEvent* event, ArdourCanvas::Item* item, ControlPoint* cp)
{
	return typed_event (item, event, ControlPointItem);
}

bool
MidiCueEditor::canvas_note_event (GdkEvent* event, ArdourCanvas::Item* item)
{
	return typed_event (item, event, NoteItem);
}

bool
MidiCueEditor::canvas_velocity_base_event (GdkEvent* event, ArdourCanvas::Item* item)
{
	return typed_event (item, event, VelocityBaseItem);
}

bool
MidiCueEditor::canvas_velocity_event (GdkEvent* event, ArdourCanvas::Item* item)
{
	return typed_event (item, event, VelocityItem);
}


Gtk::Widget&
MidiCueEditor::viewport()
{
	return *_canvas_viewport;
}

Gtk::Widget&
MidiCueEditor::toolbox ()
{
	return _toolbox;
}

void
MidiCueEditor::data_captured (timecnt_t total_duration)
{
	data_capture_duration = total_duration;

	if (!idle_update_queued.exchange (1)) {
		Glib::signal_idle().connect (sigc::mem_fun (*this, &MidiCueEditor::idle_data_captured));
	}

	samplepos_t pos = data_capture_duration.end().samples();
	_playhead_cursor->set_position (pos);
}

bool
MidiCueEditor::idle_data_captured ()
{
	double where = duration_to_pixels (data_capture_duration);

	if (where > _visible_canvas_width * 0.80) {
		set_samples_per_pixel (samples_per_pixel * 1.5);
	}

	if (view) {
		view->clip_data_recorded (data_capture_duration);
	}
	idle_update_queued.store (0);
	return false;
}

void
MidiCueEditor::set_box (std::shared_ptr<ARDOUR::TriggerBox> b)
{
	capture_connections.drop_connections ();
	idle_update_queued.store (0);

	if (b) {
		b->Captured.connect (capture_connections, invalidator (*this), boost::bind (&MidiCueEditor::data_captured, this, _1), gui_context());
		/* Don't bind a shared_ptr<TriggerBox> within the lambda */
		TriggerBox* tb (b.get());
		b->RecEnableChanged.connect (capture_connections, invalidator (*this), [&, tb]() { box_rec_enable_change (*tb); }, gui_context());
	}
}

void
MidiCueEditor::box_rec_enable_change (ARDOUR::TriggerBox const & b)
{
	if (b.record_enabled()) {
		view->begin_write();
	} else {
		view->end_write ();
	}
}

void
MidiCueEditor::trigger_rec_enable_change (ARDOUR::Trigger const & t)
{
	if (t.armed()) {
		view->begin_write();
	} else {
		view->end_write ();
	}
}

void
MidiCueEditor::set_track (std::shared_ptr<ARDOUR::MidiTrack> t)
{
	_track = t;

	view->set_track (t);

	_update_connection.disconnect ();
	capture_connections.drop_connections ();

	if (t) {
		set_box (t->triggerbox());
		_update_connection = Timers::rapid_connect (sigc::mem_fun (*this, &MidiCueEditor::maybe_update));
		_track->DropReferences.connect (track_connection, invalidator (*this), boost::bind (&MidiCueEditor::set_track, this, nullptr), gui_context());
	} else {
		set_box (nullptr);
	}
}

void
MidiCueEditor::set_region (std::shared_ptr<ARDOUR::MidiRegion> r)
{
	if (!r) {
		view->set_region (nullptr);
		return;
	}

	view->set_region (r);

	/* Compute zoom level to show entire source plus some margin if possible */

	Temporal::timecnt_t duration = Temporal::timecnt_t (r->midi_source()->length().beats());

	bool provided = false;
	std::shared_ptr<Temporal::TempoMap> map;
	std::shared_ptr<SMFSource> smf (std::dynamic_pointer_cast<SMFSource> (r->midi_source()));

	if (smf) {
		map = smf->tempo_map (provided);
	}

	if (!provided) {
		map.reset (new Temporal::TempoMap (Temporal::Tempo (120, 4), Temporal::Meter (4, 4)));
	}

	{
		EditingContext::TempoMapScope tms (*this, map);
		double width = bg->width();
		samplecnt_t samples = duration.samples();

		samplecnt_t spp = floor (samples / width);
		reset_zoom (spp);
	}
}

bool
MidiCueEditor::button_press_handler (ArdourCanvas::Item* item, GdkEvent* event, ItemType item_type)
{
	switch (event->button.button) {
	case 1:
		return button_press_handler_1 (item, event, item_type);
		break;

	case 2:
		return button_press_handler_2 (item, event, item_type);
		break;

	case 3:
		break;

	default:
		return button_press_dispatch (&event->button);
		break;

	}

	return false;
}

bool
MidiCueEditor::button_press_handler_1 (ArdourCanvas::Item* item, GdkEvent* event, ItemType item_type)
{
	NoteBase* note = nullptr;

	switch (item_type) {
	case NoteItem:
		if (mouse_mode == Editing::MouseContent) {
			/* Existing note: allow trimming/motion */
			if ((note = reinterpret_cast<NoteBase*> (item->get_data ("notebase")))) {
				if (note->big_enough_to_trim() && note->mouse_near_ends()) {
					_drags->set (new NoteResizeDrag (*this, item), event, get_canvas_cursor());
				} else {
					NoteDrag* nd = new NoteDrag (*this, item);
					nd->set_bounding_item (data_group);
					_drags->set (nd, event);
				}
			}
		}
		return true;

	case ControlPointItem:
		if (mouse_mode == Editing::MouseContent) {
			_drags->set (new ControlPointDrag (*this, item), event);
		}
		return true;
		break;

	case VelocityItem:
		if (mouse_mode == Editing::MouseContent) {
			_drags->set (new LollipopDrag (*this, item), event);
		}
		return true;
		break;

	case VelocityBaseItem:
		_drags->set (new VelocityLineDrag (*this, *static_cast<ArdourCanvas::Rectangle*>(item), false, Temporal::BeatTime), event);
		return true;
		break;

	case AutomationTrackItem:
		switch (mouse_mode) {
		case Editing::MouseContent:
			/* rubberband drag to select automation points */
			_drags->set (new RubberbandSelectDrag (*this, item, [&](GdkEvent* ev, timepos_t const & pos) { return view->automation_rb_click (ev, pos); }), event);
			break;
		case Editing::MouseDraw:
			_drags->set (new AutomationDrawDrag (*this, nullptr, *static_cast<ArdourCanvas::Rectangle*>(item), false, Temporal::BeatTime), event);
			break;
		default:
			break;
		}
		return true;
		break;

	case EditorAutomationLineItem: {
		ARDOUR::SelectionOperation op = ArdourKeyboard::selection_type (event->button.state);
		select_automation_line (&event->button, item, op);
		switch (mouse_mode) {
		case Editing::MouseContent:
			_drags->set (new LineDrag (*this, item, [&](GdkEvent* ev,timepos_t const & pos, double) { view->line_drag_click (ev, pos); }), event);
			break;
		default:
			break;
		}
		return true;
	}

	default:
		break;
	}

	return false;
}

bool
MidiCueEditor::button_press_handler_2 (ArdourCanvas::Item*, GdkEvent*, ItemType)
{
	return true;
}

bool
MidiCueEditor::button_release_handler (ArdourCanvas::Item* item, GdkEvent* event, ItemType item_type)
{
	if (!Keyboard::is_context_menu_event (&event->button)) {

		/* see if we're finishing a drag */

		if (_drags->active ()) {

			bool const r = _drags->end_grab (event);
			if (r) {
				/* grab dragged, so do nothing else */
				return true;
			}
		}
	}

	if (Keyboard::is_context_menu_event (&event->button)) {
		switch (item_type) {
		case NoteItem:
			if (internal_editing()) {
				popup_note_context_menu (item, event);
				return true;
			}
			break;
		default:
			break;
		}
	}

	return false;
}

bool
MidiCueEditor::button_press_dispatch (GdkEventButton* ev)
{
	/* this function is intended only for buttons 4 and above. */

	Gtkmm2ext::MouseButton b (ev->state, ev->button);
	return button_bindings->activate (b, Gtkmm2ext::Bindings::Press);
}

bool
MidiCueEditor::button_release_dispatch (GdkEventButton* ev)
{
	/* this function is intended only for buttons 4 and above. */

	Gtkmm2ext::MouseButton b (ev->state, ev->button);
	return button_bindings->activate (b, Gtkmm2ext::Bindings::Release);
}

bool
MidiCueEditor::motion_handler (ArdourCanvas::Item*, GdkEvent* event, bool from_autoscroll)
{
	if (_drags->active ()) {
		//drags change the snapped_cursor location, because we are snapping the thing being dragged, not the actual mouse cursor
		return _drags->motion_handler (event, from_autoscroll);
	}

	return true;
}

bool
MidiCueEditor::key_press_handler (ArdourCanvas::Item*, GdkEvent* ev, ItemType)
{

	switch (ev->key.keyval) {
	case GDK_d:
		set_mouse_mode (Editing::MouseDraw);
		break;
	case GDK_e:
		set_mouse_mode (Editing::MouseContent);
		break;
	}

	return true;
}

bool
MidiCueEditor::key_release_handler (ArdourCanvas::Item*, GdkEvent*, ItemType)
{
	return true;
}

void
MidiCueEditor::set_mouse_mode (Editing::MouseMode m, bool force)
{
	if (m != Editing::MouseDraw && m != Editing::MouseContent) {
		return;
	}

	EditingContext::set_mouse_mode (m, force);
}

void
MidiCueEditor::step_mouse_mode (bool next)
{
}

Editing::MouseMode
MidiCueEditor::current_mouse_mode () const
{
	return mouse_mode;
}

bool
MidiCueEditor::internal_editing() const
{
	return true;
}

RegionSelection
MidiCueEditor::region_selection()
{
	RegionSelection rs;
	return rs;
}

static void
edit_last_mark_label (std::vector<ArdourCanvas::Ruler::Mark>& marks, const std::string& newlabel)
{
	ArdourCanvas::Ruler::Mark copy = marks.back();
	copy.label = newlabel;
	marks.pop_back ();
	marks.push_back (copy);
}

void
MidiCueEditor::metric_get_bbt (std::vector<ArdourCanvas::Ruler::Mark>& marks, samplepos_t leftmost, samplepos_t rightmost, gint /*maxchars*/)
{
	if (_session == 0) {
		return;
	}

	bool provided = false;
	std::shared_ptr<Temporal::TempoMap> tmap;

	if (view && view->midi_region()) {
		std::shared_ptr<SMFSource> smf (std::dynamic_pointer_cast<SMFSource> (view->midi_region()->midi_source()));

		if (smf) {
			tmap = smf->tempo_map (provided);
		}
	}

	if (!provided) {
		tmap.reset (new Temporal::TempoMap (Temporal::Tempo (120, 4), Temporal::Meter (4, 4)));
	}

	EditingContext::TempoMapScope tms (*this, tmap);
	Temporal::TempoMapPoints::const_iterator i;

	char buf[64];
	Temporal::BBT_Time next_beat;
	double bbt_position_of_helper;
	bool helper_active = false;
	ArdourCanvas::Ruler::Mark mark;
	const samplecnt_t sr (_session->sample_rate());

	Temporal::TempoMapPoints grid;
	grid.reserve (4096);


	/* prevent negative values of leftmost from creeping into tempomap
	 */

	const Beats left = tmap->quarters_at_sample (leftmost).round_down_to_beat();
	const Beats lower_beat = (left < Beats() ? Beats() : left);

	using std::max;

	switch (bbt_ruler_scale) {

	case bbt_show_quarters:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 0, 1);
		break;
	case bbt_show_eighths:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 0, 2);
		break;
	case bbt_show_sixteenths:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 0, 4);
		break;
	case bbt_show_thirtyseconds:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 0, 8);
		break;
	case bbt_show_sixtyfourths:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 0, 16);
		break;
	case bbt_show_onetwentyeighths:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 0, 32);
		break;

	case bbt_show_1:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 1);
		break;

	case bbt_show_4:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 4);
		break;

	case bbt_show_16:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 16);
		break;

	case bbt_show_64:
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 64);
		break;

	default:
		/* bbt_show_many */
		tmap->get_grid (grid, max (tmap->superclock_at (lower_beat), (superclock_t) 0), samples_to_superclock (rightmost, sr), 128);
		break;
	}

#if 0 // DEBUG GRID
	for (auto const& g : grid) {
		std::cout << "Grid " << g.time() <<  " Beats: " << g.beats() << " BBT: " << g.bbt() << " sample: " << g.sample(_session->nominal_sample_rate ()) << "\n";
	}
#endif

	if (distance (grid.begin(), grid.end()) == 0) {
		return;
	}

	/* we can accent certain lines depending on the user's Grid choice */
	/* for example, even in a 4/4 meter we can draw a grid with triplet-feel */
	/* and in this case you will want the accents on '3s' not '2s' */
	uint32_t bbt_divisor = 2;

	using namespace Editing;

	switch (_grid_type) {
	case GridTypeBeatDiv3:
		bbt_divisor = 3;
		break;
	case GridTypeBeatDiv5:
		bbt_divisor = 5;
		break;
	case GridTypeBeatDiv6:
		bbt_divisor = 3;
		break;
	case GridTypeBeatDiv7:
		bbt_divisor = 7;
		break;
	case GridTypeBeatDiv10:
		bbt_divisor = 5;
		break;
	case GridTypeBeatDiv12:
		bbt_divisor = 3;
		break;
	case GridTypeBeatDiv14:
		bbt_divisor = 7;
		break;
	case GridTypeBeatDiv16:
		break;
	case GridTypeBeatDiv20:
		bbt_divisor = 5;
		break;
	case GridTypeBeatDiv24:
		bbt_divisor = 6;
		break;
	case GridTypeBeatDiv28:
		bbt_divisor = 7;
		break;
	case GridTypeBeatDiv32:
		break;
	default:
		bbt_divisor = 2;
		break;
	}

	uint32_t bbt_beat_subdivision = 1;
	switch (bbt_ruler_scale) {
	case bbt_show_quarters:
		bbt_beat_subdivision = 1;
		break;
	case bbt_show_eighths:
		bbt_beat_subdivision = 1;
		break;
	case bbt_show_sixteenths:
		bbt_beat_subdivision = 2;
		break;
	case bbt_show_thirtyseconds:
		bbt_beat_subdivision = 4;
		break;
	case bbt_show_sixtyfourths:
		bbt_beat_subdivision = 8;
		break;
	case bbt_show_onetwentyeighths:
		bbt_beat_subdivision = 16;
		break;
	default:
		bbt_beat_subdivision = 1;
		break;
	}

	bbt_beat_subdivision *= bbt_divisor;

	switch (bbt_ruler_scale) {

	case bbt_show_many:
		snprintf (buf, sizeof(buf), "cannot handle %" PRIu32 " bars", bbt_bars);
		mark.style = ArdourCanvas::Ruler::Mark::Major;
		mark.label = buf;
		mark.position = leftmost;
		marks.push_back (mark);
		break;

	case bbt_show_64:
			for (i = grid.begin(); i != grid.end(); i++) {
				BBT_Time bbt ((*i).bbt());
				if (bbt.is_bar()) {
					if (bbt.bars % 64 == 1) {
						if (bbt.bars % 256 == 1) {
							snprintf (buf, sizeof(buf), "%" PRIu32, bbt.bars);
							mark.style = ArdourCanvas::Ruler::Mark::Major;
						} else {
							buf[0] = '\0';
							if (bbt.bars % 256 == 129)  {
								mark.style = ArdourCanvas::Ruler::Mark::Minor;
							} else {
								mark.style = ArdourCanvas::Ruler::Mark::Micro;
							}
						}
						mark.label = buf;
						mark.position = (*i).sample (sr);
						marks.push_back (mark);
					}
				}
			}
			break;

	case bbt_show_16:
		for (i = grid.begin(); i != grid.end(); i++) {
			BBT_Time bbt ((*i).bbt());
			if (bbt.is_bar()) {
			  if (bbt.bars % 16 == 1) {
				if (bbt.bars % 64 == 1) {
					snprintf (buf, sizeof(buf), "%" PRIu32, bbt.bars);
					mark.style = ArdourCanvas::Ruler::Mark::Major;
				} else {
					buf[0] = '\0';
					if (bbt.bars % 64 == 33)  {
						mark.style = ArdourCanvas::Ruler::Mark::Minor;
					} else {
						mark.style = ArdourCanvas::Ruler::Mark::Micro;
					}
				}
				mark.label = buf;
				mark.position = (*i).sample(sr);
				marks.push_back (mark);
			  }
			}
		}
	  break;

	case bbt_show_4:
		for (i = grid.begin(); i != grid.end(); ++i) {
			BBT_Time bbt ((*i).bbt());
			if (bbt.is_bar()) {
				if (bbt.bars % 4 == 1) {
					if (bbt.bars % 16 == 1) {
						snprintf (buf, sizeof(buf), "%" PRIu32, bbt.bars);
						mark.style = ArdourCanvas::Ruler::Mark::Major;
				} else {
						buf[0] = '\0';
						mark.style = ArdourCanvas::Ruler::Mark::Minor;
					}
					mark.label = buf;
					mark.position = (*i).sample (sr);
					marks.push_back (mark);
				}
			}
		}
	  break;

	case bbt_show_1:
		for (i = grid.begin(); i != grid.end(); ++i) {
			BBT_Time bbt ((*i).bbt());
			if (bbt.is_bar()) {
				snprintf (buf, sizeof(buf), "%" PRIu32, bbt.bars);
				mark.style = ArdourCanvas::Ruler::Mark::Major;
				mark.label = buf;
				mark.position = (*i).sample (sr);
				marks.push_back (mark);
			}
		}
	break;

	case bbt_show_quarters:

		mark.label = "";
		mark.position = leftmost;
		mark.style = ArdourCanvas::Ruler::Mark::Micro;
		marks.push_back (mark);

		for (i = grid.begin(); i != grid.end(); ++i) {

			BBT_Time bbt ((*i).bbt());

			if ((*i).sample (sr) < leftmost && (bbt_bar_helper_on)) {
				snprintf (buf, sizeof(buf), "<%" PRIu32 "|%" PRIu32, bbt.bars, bbt.beats);
				edit_last_mark_label (marks, buf);
			} else {

				if (bbt.is_bar()) {
					mark.style = ArdourCanvas::Ruler::Mark::Major;
					snprintf (buf, sizeof(buf), "%" PRIu32, bbt.bars);
				} else if ((bbt.beats % 2) == 1) {
					mark.style = ArdourCanvas::Ruler::Mark::Minor;
					buf[0] = '\0';
				} else {
					mark.style = ArdourCanvas::Ruler::Mark::Micro;
					buf[0] = '\0';
				}
				mark.label = buf;
				mark.position = (*i).sample (sr);
				marks.push_back (mark);
			}
		}
		break;

	case bbt_show_eighths:
	case bbt_show_sixteenths:
	case bbt_show_thirtyseconds:
	case bbt_show_sixtyfourths:
	case bbt_show_onetwentyeighths:

		bbt_position_of_helper = leftmost + (3 * get_current_zoom ());

		mark.label = "";
		mark.position = leftmost;
		mark.style = ArdourCanvas::Ruler::Mark::Micro;
		marks.push_back (mark);

		for (i = grid.begin(); i != grid.end(); ++i) {

			BBT_Time bbt ((*i).bbt());

			if ((*i).sample (sr) < leftmost && (bbt_bar_helper_on)) {
				snprintf (buf, sizeof(buf), "<%" PRIu32 "|%" PRIu32, bbt.bars, bbt.beats);
				edit_last_mark_label (marks, buf);
				helper_active = true;
			} else {

				if (bbt.is_bar()) {
					mark.style = ArdourCanvas::Ruler::Mark::Major;
					snprintf (buf, sizeof(buf), "%" PRIu32, bbt.bars);
				} else if (bbt.ticks == 0) {
					mark.style = ArdourCanvas::Ruler::Mark::Minor;
					snprintf (buf, sizeof(buf), "%" PRIu32, bbt.beats);
				} else {
					mark.style = ArdourCanvas::Ruler::Mark::Micro;
					buf[0] = '\0';
				}

				if (((*i).sample(sr) < bbt_position_of_helper) && helper_active) {
					buf[0] = '\0';
				}
				mark.label =  buf;
				mark.position = (*i).sample (sr);
				marks.push_back (mark);
			}
		}

		break;
	}
}


void
MidiCueEditor::mouse_mode_toggled (Editing::MouseMode m)
{
	Glib::RefPtr<Gtk::Action>       act  = get_mouse_mode_action (m);
	Glib::RefPtr<Gtk::ToggleAction> tact = Glib::RefPtr<Gtk::ToggleAction>::cast_dynamic (act);

	if (!tact->get_active()) {
		/* this was just the notification that the old mode has been
		 * left. we'll get called again with the new mode active in a
		 * jiffy.
		 */
		return;
	}

	mouse_mode = m;

	/* this should generate a new enter event which will
	   trigger the appropriate cursor.
	*/

	if (_canvas) {
		_canvas->re_enter ();
	}
}

int
MidiCueEditor::set_state (XMLNode const & node, int version)
{
	set_common_editing_state (node);
	return 0;
}

XMLNode&
MidiCueEditor::get_state () const
{
	XMLNode* node (new XMLNode (_("MIDICueEditor")));
	get_common_editing_state (*node);
	return *node;
}

/** @param allow_horiz true to allow horizontal autoscroll, otherwise false.
 *
 *  @param allow_vert true to allow vertical autoscroll, otherwise false.
 *
 */
void
MidiCueEditor::maybe_autoscroll (bool allow_horiz, bool allow_vert, bool from_headers)
{
	if (!UIConfiguration::instance().get_autoscroll_editor () || autoscroll_active ()) {
		return;
	}

	/* define a rectangular boundary for scrolling. If the mouse moves
	 * outside of this area and/or continue to be outside of this area,
	 * then we will continuously auto-scroll the canvas in the appropriate
	 * direction(s)
	 *
	 * the boundary is defined in coordinates relative to canvas' own
	 * window since that is what we're going to call ::get_pointer() on
	 * during autoscrolling to determine if we're still outside the
	 * boundary or not.
	 */

	ArdourCanvas::Rect scrolling_boundary;
	Gtk::Allocation alloc;

	alloc = get_canvas()->get_allocation ();

	alloc.set_x (0);
	alloc.set_y (0);

	if (allow_vert) {
		/* reduce height by the height of the timebars, which happens
		   to correspond to the position of the data_group.
		*/

		alloc.set_height (alloc.get_height() - data_group->position().y);
		alloc.set_y (alloc.get_y() + data_group->position().y);

		/* now reduce it again so that we start autoscrolling before we
		 * move off the top or bottom of the canvas
		 */

		alloc.set_height (alloc.get_height() - 20);
		alloc.set_y (alloc.get_y() + 10);
	}

	if (allow_horiz && (alloc.get_width() > 20)) {

		if (prh) {
			double w, h;
			prh->size_request (w, h);

			alloc.set_width (alloc.get_width() - w);
			alloc.set_x (alloc.get_x() + w);
		}

		/* the effective width of the autoscroll boundary so
		   that we start scrolling before we hit the edge.

		   this helps when the window is slammed up against the
		   right edge of the screen, making it hard to scroll
		   effectively.
		*/

		alloc.set_width (alloc.get_width() - 20);
		alloc.set_x (alloc.get_x() + 10);
	}

	scrolling_boundary = ArdourCanvas::Rect (alloc.get_x(), alloc.get_y(), alloc.get_x() + alloc.get_width(), alloc.get_y() + alloc.get_height());

	int x, y;
	Gdk::ModifierType mask;

	get_canvas()->get_window()->get_pointer (x, y, mask);

	if ((allow_horiz && ((x < scrolling_boundary.x0 && _leftmost_sample > 0) || x >= scrolling_boundary.x1)) ||
	    (allow_vert && ((y < scrolling_boundary.y0 && vertical_adjustment.get_value() > 0)|| y >= scrolling_boundary.y1))) {
		start_canvas_autoscroll (allow_horiz, allow_vert, scrolling_boundary);
	}
}

bool
MidiCueEditor::autoscroll_active () const
{
	return autoscroll_connection.connected ();
}

bool
MidiCueEditor::autoscroll_canvas ()
{
	using std::max;
	using std::min;
	int x, y;
	Gdk::ModifierType mask;
	sampleoffset_t dx = 0;
	bool no_stop = false;
	Gtk::Window* toplevel = dynamic_cast<Gtk::Window*>(_canvas_viewport->get_toplevel());

	if (!toplevel) {
		return false;
	}

	get_canvas()->get_window()->get_pointer (x, y, mask);

	VisualChange vc;
	bool vertical_motion = false;

	if (autoscroll_horizontal_allowed) {

		samplepos_t new_sample = _leftmost_sample;

		/* horizontal */

		if (x > autoscroll_boundary.x1) {

			/* bring it back into view */
			dx = x - autoscroll_boundary.x1;
			dx += 10 + (2 * (autoscroll_cnt/2));

			dx = pixel_to_sample (dx);

			dx *= UIConfiguration::instance().get_draggable_playhead_speed();

			if (_leftmost_sample < max_samplepos - dx) {
				new_sample = _leftmost_sample + dx;
			} else {
				new_sample = max_samplepos;
			}

			no_stop = true;

		} else if (x < autoscroll_boundary.x0) {

			dx = autoscroll_boundary.x0 - x;
			dx += 10 + (2 * (autoscroll_cnt/2));

			dx = pixel_to_sample (dx);

			dx *= UIConfiguration::instance().get_draggable_playhead_speed();

			if (_leftmost_sample >= dx) {
				new_sample = _leftmost_sample - dx;
			} else {
				new_sample = 0;
			}

			no_stop = true;
		}

		if (new_sample != _leftmost_sample) {
			vc.time_origin = new_sample;
			vc.add (VisualChange::TimeOrigin);
		}
	}

	if (autoscroll_vertical_allowed) {

		// const double vertical_pos = vertical_adjustment.get_value();
		const int speed_factor = 10;

		/* vertical */

		if (y < autoscroll_boundary.y0) {

			/* scroll to make higher tracks visible */

			if (autoscroll_cnt && (autoscroll_cnt % speed_factor == 0)) {
				// XXX SCROLL UP
				vertical_motion = true;
			}
			no_stop = true;

		} else if (y > autoscroll_boundary.y1) {

			if (autoscroll_cnt && (autoscroll_cnt % speed_factor == 0)) {
				// XXX SCROLL DOWN
				vertical_motion = true;
			}
			no_stop = true;
		}

	}

	if (vc.pending || vertical_motion) {

		/* change horizontal first */

		if (vc.pending) {
			visual_changer (vc);
		}

		/* now send a motion event to notify anyone who cares
		   that we have moved to a new location (because we scrolled)
		*/

		GdkEventMotion ev;

		ev.type = GDK_MOTION_NOTIFY;
		ev.state = Gdk::BUTTON1_MASK;

		/* the motion handler expects events in canvas coordinate space */

		/* we asked for the mouse position above (::get_pointer()) via
		 * our own top level window (we being the Editor). Convert into
		 * coordinates within the canvas window.
		 */

		int cx;
		int cy;

		//toplevel->translate_coordinates (*get_canvas(), x, y, cx,
		//cy);
		cx = x;
		cy = y;

		/* clamp x and y to remain within the autoscroll boundary,
		 * which is defined in window coordinates
		 */

		x = min (max ((ArdourCanvas::Coord) cx, autoscroll_boundary.x0), autoscroll_boundary.x1);
		y = min (max ((ArdourCanvas::Coord) cy, autoscroll_boundary.y0), autoscroll_boundary.y1);

		/* now convert from Editor window coordinates to canvas
		 * window coordinates
		 */

		ArdourCanvas::Duple d = get_canvas()->window_to_canvas (ArdourCanvas::Duple (cx, cy));
		ev.x = d.x;
		ev.y = d.y;
		ev.state = mask;

		motion_handler (0, (GdkEvent*) &ev, true);

	} else if (no_stop) {

		/* not changing visual state but pointer is outside the scrolling boundary
		 * so we still need to deliver a fake motion event
		 */

		GdkEventMotion ev;

		ev.type = GDK_MOTION_NOTIFY;
		ev.state = Gdk::BUTTON1_MASK;

		/* the motion handler expects events in canvas coordinate space */

		/* first convert from Editor window coordinates to canvas
		 * window coordinates
		 */

		int cx;
		int cy;

		/* clamp x and y to remain within the visible area. except
		 * .. if horizontal scrolling is allowed, always allow us to
		 * move back to zero
		 */

		if (autoscroll_horizontal_allowed) {
			x = min (max ((ArdourCanvas::Coord) x, 0.0), autoscroll_boundary.x1);
		} else {
			x = min (max ((ArdourCanvas::Coord) x, autoscroll_boundary.x0), autoscroll_boundary.x1);
		}
		y = min (max ((ArdourCanvas::Coord) y, autoscroll_boundary.y0), autoscroll_boundary.y1);

		// toplevel->translate_coordinates (*get_canvas_viewport(), x,
		// y, cx, cy);
		cx = x;
		cy = y;

		ArdourCanvas::Duple d = get_canvas()->window_to_canvas (ArdourCanvas::Duple (cx, cy));
		ev.x = d.x;
		ev.y = d.y;
		ev.state = mask;

		motion_handler (0, (GdkEvent*) &ev, true);

	} else {
		stop_canvas_autoscroll ();
		return false;
	}

	autoscroll_cnt++;

	return true; /* call me again */
}

void
MidiCueEditor::start_canvas_autoscroll (bool allow_horiz, bool allow_vert, const ArdourCanvas::Rect& boundary)
{
	if (!_session) {
		return;
	}

	stop_canvas_autoscroll ();

	autoscroll_horizontal_allowed = allow_horiz;
	autoscroll_vertical_allowed = allow_vert;
	autoscroll_boundary = boundary;

	/* do the first scroll right now
	*/

	autoscroll_canvas ();

	/* scroll again at very very roughly 30FPS */

	autoscroll_connection = Glib::signal_timeout().connect (sigc::mem_fun (*this, &MidiCueEditor::autoscroll_canvas), 30);
}

void
MidiCueEditor::stop_canvas_autoscroll ()
{
	autoscroll_connection.disconnect ();
	autoscroll_cnt = 0;
}

void
MidiCueEditor::visual_changer (const VisualChange& vc)
{
	/**
	 * Changed first so the correct horizontal canvas position is calculated in
	 * EditingContext::set_horizontal_position
	 */
	if (vc.pending & VisualChange::ZoomLevel) {
		set_samples_per_pixel (vc.samples_per_pixel);
	}

	if (vc.pending & VisualChange::TimeOrigin) {
		double new_time_origin = sample_to_pixel_unrounded (vc.time_origin);
		set_horizontal_position (new_time_origin);
	}

	if (vc.pending & VisualChange::YOrigin) {
		vertical_adjustment.set_value (vc.y_origin);
	}

	/**
	 * Now the canvas is in the final state before render the canvas items that
	 * support the Item::prepare_for_render interface can calculate the correct
	 * item to visible canvas intersection.
	 */
	if (vc.pending & VisualChange::ZoomLevel) {
		on_samples_per_pixel_changed ();

		// update_tempo_based_rulers ();
	}

	if (!(vc.pending & VisualChange::ZoomLevel)) {
		/* If the canvas is not being zoomed then the canvas items will not change
		 * and cause Item::prepare_for_render to be called so do it here manually.
		 * Not ideal, but I can't think of a better solution atm.
		 */
		get_canvas()->prepare_for_render();
	}

	/* If we are only scrolling vertically there is no need to update these */
	if (vc.pending != VisualChange::YOrigin) {
		// XXX update_fixed_rulers ();
		//  XXX redisplay_grid (true);
	}
}

void
MidiCueEditor::on_samples_per_pixel_changed ()
{
	if (view) {
		view->set_samples_per_pixel (samples_per_pixel);
	}
}

void
MidiCueEditor::midi_action (void (MidiView::*method)())
{
	if (!view) {
		return;
	}

	(view->*method) ();
}

void
MidiCueEditor::escape ()
{
	if (!view) {
		return;
	}

	view->clear_note_selection ();
}
Gdk::Cursor*
MidiCueEditor::which_track_cursor () const
{
	return _cursors->grabber;
}

Gdk::Cursor*
MidiCueEditor::which_mode_cursor () const
{
	Gdk::Cursor* mode_cursor = MouseCursors::invalid_cursor ();

	switch (mouse_mode) {
	case Editing::MouseContent:
		/* don't use mode cursor, pick a grabber cursor based on the item */
		break;

	case Editing::MouseDraw:
		mode_cursor = _cursors->midi_pencil;
		break;

	default:
		break;
	}

	return mode_cursor;
}

Gdk::Cursor*
MidiCueEditor::which_trim_cursor (bool left_side) const
{
	abort ();
	/*NOTREACHED*/
	return nullptr;
}


Gdk::Cursor*
MidiCueEditor::which_canvas_cursor (ItemType type) const
{
	Gdk::Cursor* cursor = which_mode_cursor ();

	if (mouse_mode == Editing::MouseContent) {

		/* find correct cursor to use in object/smart mode */
		switch (type) {
		case AutomationTrackItem:
			cursor = which_track_cursor ();
			break;
		case PlayheadCursorItem:
			cursor = _cursors->grabber;
			break;
		case SelectionItem:
			cursor = _cursors->selector;
			break;
		case ControlPointItem:
			cursor = _cursors->fader;
			break;
		case GainLineItem:
			cursor = _cursors->cross_hair;
			break;
		case EditorAutomationLineItem:
			cursor = _cursors->cross_hair;
			break;
		case StartSelectionTrimItem:
			cursor = _cursors->left_side_trim;
			break;
		case EndSelectionTrimItem:
			cursor = _cursors->right_side_trim;
			break;
		case NoteItem:
			cursor = _cursors->grabber_note;
		default:
			break;
		}

	} else if (mouse_mode == Editing::MouseDraw) {

		/* ControlPointItem is not really specific to region gain mode
		   but it is the same cursor so don't worry about this for now.
		   The result is that we'll see the fader cursor if we enter
		   non-region-gain-line control points while in MouseDraw
		   mode, even though we can't edit them in this mode.
		*/

		switch (type) {
		case ControlPointItem:
			cursor = _cursors->fader;
			break;
		case NoteItem:
			cursor = _cursors->grabber_note;
		default:
			break;
		}
	}

	return cursor;
}

bool
MidiCueEditor::enter_handler (ArdourCanvas::Item* item, GdkEvent* ev, ItemType item_type)
{
	EditorAutomationLine* al;

	choose_canvas_cursor_on_entry (item_type);

	switch (item_type) {
	case AutomationTrackItem:
		/* item is the base rectangle */
		al = reinterpret_cast<EditorAutomationLine*> (item->get_data ("line"));
		al->track_entered ();
		break;

	case EditorAutomationLineItem:
		{
			ArdourCanvas::Line *line = dynamic_cast<ArdourCanvas::Line *> (item);

			if (line) {
				line->set_outline_color (UIConfiguration::instance().color ("entered automation line"));
			}
		}
		break;
	default:
		break;
	}

	return true;
}

bool
MidiCueEditor::leave_handler (ArdourCanvas::Item* item, GdkEvent* ev, ItemType item_type)
{
	EditorAutomationLine* al;

	if (!_enter_stack.empty()) {
		_enter_stack.pop_back();
	}

	switch (item_type) {
	case ControlPointItem:
		_verbose_cursor->hide ();
		break;

	case EditorAutomationLineItem:
		al = reinterpret_cast<EditorAutomationLine*> (item->get_data ("line"));
		{
			ArdourCanvas::Line *line = dynamic_cast<ArdourCanvas::Line *> (item);
			if (line) {
				line->set_outline_color (al->get_line_color());
			}
		}
		if (ev->crossing.detail != GDK_NOTIFY_INFERIOR) {
			al->track_exited ();
		}
		break;

	default:
		break;
	}


	return true;
}

std::list<SelectableOwner*>
MidiCueEditor::selectable_owners()
{
	if (view) {
		return view->selectable_owners();
	}

	return std::list<SelectableOwner*> ();
}