Rudimentary ghost note when adding MIDI notes to a region, as per #3180.

git-svn-id: svn://localhost/ardour2/branches/3.0@7162 d708f5d6-7413-0410-9779-e7cbd77b26cf

gtk2_ardour/canvas-note.h

@@ -55,6 +55,22 @@ public:
 	}
 };
 
+class NoEventCanvasNote : public CanvasNote
+{
+public:
+	NoEventCanvasNote (
+		MidiRegionView& region,
+		Group& group,
+		const boost::shared_ptr<NoteType> note = boost::shared_ptr<NoteType>()
+		)
+		: CanvasNote (region, group, note) {}
+
+	double point_vfunc(double, double, int, int, GnomeCanvasItem**) {
+		/* return a huge value to tell the canvas that we're never the item for an event */
+		return 9999999999999.0;
+	}
+};
+
 } // namespace Gnome
 } // namespace Canvas
 

gtk2_ardour/editor.cc

@@ -2128,7 +2128,9 @@ Editor::set_snap_to (SnapType st)
 	default:
 		/* relax */
 		break;
-    }
+	}
+
+	SnapChanged (); /* EMIT SIGNAL */
 }
 
 void

gtk2_ardour/midi_region_view.cc

@@ -85,6 +85,7 @@ MidiRegionView::MidiRegionView (ArdourCanvas::Group *parent, RouteTimeAxisView &
 	, _note_group(new ArdourCanvas::Group(*parent))
 	, _delta_command(0)
 	, _diff_command(0)
+	, _ghost_note(0)
 	, _mouse_state(None)
 	, _pressed_button(0)
 	, _sort_needed (true)
@@ -107,6 +108,7 @@ MidiRegionView::MidiRegionView (ArdourCanvas::Group *parent, RouteTimeAxisView &
 	, _note_group(new ArdourCanvas::Group(*parent))
 	, _delta_command(0)
 	, _diff_command(0)
+	, _ghost_note(0)
 	, _mouse_state(None)
 	, _pressed_button(0)
 	, _sort_needed (true)
@@ -130,6 +132,7 @@ MidiRegionView::MidiRegionView (const MidiRegionView& other)
 	, _note_group(new ArdourCanvas::Group(*get_canvas_group()))
 	, _delta_command(0)
 	, _diff_command(0)
+	, _ghost_note(0)
 	, _mouse_state(None)
 	, _pressed_button(0)
 	, _sort_needed (true)
@@ -156,6 +159,7 @@ MidiRegionView::MidiRegionView (const MidiRegionView& other, boost::shared_ptr<M
 	, _note_group(new ArdourCanvas::Group(*get_canvas_group()))
 	, _delta_command(0)
 	, _diff_command(0)
+	, _ghost_note(0)
 	, _mouse_state(None)
 	, _pressed_button(0)
 	, _sort_needed (true)
@@ -216,6 +220,8 @@ MidiRegionView::init (Gdk::Color const & basic_color, bool wfd)
 
 	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 ());
 }
 
 bool
@@ -363,12 +369,26 @@ MidiRegionView::canvas_event(GdkEvent* ev)
 		return true;
 
 	case GDK_ENTER_NOTIFY:
+	{
 		/* FIXME: do this on switch to note tool, too, if the pointer is already in */
 		Keyboard::magic_widget_grab_focus();
 		group->grab_focus();
+
+		if (editor.current_mouse_mode() == MouseRange) {
+			create_ghost_note (ev->crossing.x, ev->crossing.y);
+		}
 		break;
+	}
+
+	case GDK_LEAVE_NOTIFY:
+	{
+		delete _ghost_note;
+		_ghost_note = 0;
+		break;
+	}
 
 	case GDK_MOTION_NOTIFY:
+	{
 		event_x = ev->motion.x;
 		event_y = ev->motion.y;
 		group->w2i(event_x, event_y);
@@ -379,6 +399,10 @@ MidiRegionView::canvas_event(GdkEvent* ev)
 		// convert event_frame back to local coordinates relative to position
 		event_frame -= _region->position();
 
+		if (_ghost_note) {
+			update_ghost_note (ev->motion.x, ev->motion.y);
+		}
+		
 		switch (_mouse_state) {
 		case Pressed: // Maybe start a drag, if we've moved a bit
 
@@ -477,6 +501,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
 			break;
 		}
 		break;
+	}
 
 	case GDK_BUTTON_RELEASE:
 		event_x = ev->motion.x;
@@ -533,7 +558,7 @@ MidiRegionView::canvas_event(GdkEvent* ev)
 			drag_rect = 0;
 		default: break;
 		}
-
+		
 	default: break;
 	}
 
@@ -2689,3 +2714,54 @@ MidiRegionView::selection_as_notelist (Notes& selected, bool allow_all_if_none_s
 		}
 	}
 }
+
+void
+MidiRegionView::update_ghost_note (double x, double y)
+{
+	_last_ghost_x = x;
+	_last_ghost_y = y;
+	
+	group->w2i (x, y);
+	nframes64_t f = trackview.editor().pixel_to_frame (x) + _region->position ();
+	trackview.editor().snap_to (f);
+	f -= _region->position ();
+
+	bool success;
+	Evoral::MusicalTime beats = trackview.editor().get_grid_type_as_beats (success, f);
+	if (!success) {
+		beats = 1;
+	}
+	
+	double length = frames_to_beats (snap_frame_to_frame (f + beats_to_frames (beats)) - f);
+	
+	_ghost_note->note()->set_time (frames_to_beats (f + _region->start()));
+	_ghost_note->note()->set_length (length);
+	_ghost_note->note()->set_note (midi_stream_view()->y_to_note (y));
+
+	update_note (_ghost_note);
+}
+
+void
+MidiRegionView::create_ghost_note (double x, double y)
+{
+	delete _ghost_note;
+	_ghost_note = 0;
+
+	boost::shared_ptr<NoteType> g (new NoteType);
+	_ghost_note = new NoEventCanvasNote (*this, *group, g);
+	update_ghost_note (x, y);
+	_ghost_note->show ();
+
+	_last_ghost_x = x;
+	_last_ghost_y = y;
+}
+
+void
+MidiRegionView::snap_changed ()
+{
+	if (!_ghost_note) {
+		return;
+	}
+	
+	create_ghost_note (_last_ghost_x, _last_ghost_y);
+}

gtk2_ardour/midi_region_view.h

@@ -369,6 +369,9 @@ class MidiRegionView : public RegionView
 	ArdourCanvas::Group*                 _note_group;
 	ARDOUR::MidiModel::DeltaCommand*     _delta_command;
 	ARDOUR::MidiModel::DiffCommand*      _diff_command;
+	ArdourCanvas::CanvasNote*            _ghost_note;
+	double                               _last_ghost_x;
+	double                               _last_ghost_y;
 
 	MouseState _mouse_state;
 	int _pressed_button;
@@ -400,12 +403,17 @@ class MidiRegionView : public RegionView
 
 	void update_note (ArdourCanvas::CanvasNote*);
 	void update_hit (ArdourCanvas::CanvasHit*);
+	void create_ghost_note (double, double);
+	void update_ghost_note (double, double);
 
 	MidiListEditor* _list_editor;
 	bool no_sound_notes;
 
         PBD::ScopedConnection note_delete_connection;
         void maybe_remove_deleted_note_from_selection (ArdourCanvas::CanvasNoteEvent*);
+
+	void snap_changed ();
+	PBD::ScopedConnection snap_changed_connection;
 };
 
 

gtk2_ardour/public_editor.h

@@ -364,6 +364,8 @@ class PublicEditor : public Gtk::Window, public PBD::StatefulDestructible {
 
 	friend bool relay_key_press (GdkEventKey*, Gtk::Window*);
 	friend bool forward_key_press (GdkEventKey*);
+
+	PBD::Signal0<void> SnapChanged;
 };
 
 #endif // __gtk_ardour_public_editor_h__