+/** Update the x positions of our representation of a parent's note.
+ * @param parent The CanvasNote from the parent MidiRegionView.
+ */
+void
+MidiGhostRegion::update_note (ArdourCanvas::CanvasNote* parent)
+{
+ Event* ev = find_event (parent);
+ if (!ev) {
+ return;
+ }
+
+ double const x1 = parent->property_x1 ();
+ double const x2 = parent->property_x2 ();
+ ev->rect->property_x1 () = x1;
+ ev->rect->property_x2 () = x2;
+}
+
+void
+MidiGhostRegion::remove_note (ArdourCanvas::CanvasNoteEvent* note)
+{
+ Event* ev = find_event (note);
+ if (!ev) {
+ return;
+ }
+
+ events.remove (ev);
+ delete ev;
+ _optimization_iterator = events.end ();
+}
+
+/** Given a note in our parent region (ie the actual MidiRegionView), find our
+ * representation of it.
+ * @return Our Event, or 0 if not found.
+ */
+
+MidiGhostRegion::Event *
+MidiGhostRegion::find_event (ArdourCanvas::CanvasNoteEvent* parent)
+{
+ /* we are using _optimization_iterator to speed up the common case where a caller
+ is going through our notes in order.
+ */
+
+ if (_optimization_iterator != events.end()) {
+ ++_optimization_iterator;
+ }
+
+ if (_optimization_iterator != events.end() && (*_optimization_iterator)->event == parent) {
+ return *_optimization_iterator;
+ }
+
+ for (_optimization_iterator = events.begin(); _optimization_iterator != events.end(); ++_optimization_iterator) {
+ if ((*_optimization_iterator)->event == parent) {
+ return *_optimization_iterator;
+ }
+ }
+
+ return 0;
+}