+
+// if (!mouse_frame (m, ignored)) {
+// /* mouse is not in a canvas, try playhead+selected marker.
+// this is probably most true when using menus.
+// */
+//
+// if (selection->markers.empty()) {
+// return false;
+// }
+
+// start = selection->markers.front()->position();
+// end = _session->audible_frame();
+
+// } else {
+
+// switch (_edit_point) {
+// case EditAtPlayhead:
+// if (selection->markers.empty()) {
+// /* use mouse + playhead */
+// start = m;
+// end = _session->audible_frame();
+// } else {
+// /* use playhead + selected marker */
+// start = _session->audible_frame();
+// end = selection->markers.front()->position();
+// }
+// break;
+
+// case EditAtMouse:
+// /* use mouse + selected marker */
+// if (selection->markers.empty()) {
+// start = m;
+// end = _session->audible_frame();
+// } else {
+// start = selection->markers.front()->position();
+// end = m;
+// }
+// break;
+
+// case EditAtSelectedMarker:
+// /* use mouse + selected marker */
+// if (selection->markers.empty()) {
+
+// MessageDialog win (_("No edit range defined"),
+// false,
+// MESSAGE_INFO,
+// BUTTONS_OK);
+
+// win.set_secondary_text (
+// _("the edit point is Selected Marker\nbut there is no selected marker."));
+
+
+// win.set_default_response (RESPONSE_CLOSE);
+// win.set_position (Gtk::WIN_POS_MOUSE);
+// win.show_all();
+
+// win.run ();
+
+// return false; // NO RANGE
+// }
+// start = selection->markers.front()->position();
+// end = m;
+// break;
+// }
+// }
+
+// if (start == end) {
+// return false;
+// }
+
+// if (start > end) {
+// swap (start, end);
+// }