+
+/** Queue a change for the Editor viewport x origin to follow the playhead */
+void
+Editor::reset_x_origin_to_follow_playhead ()
+{
+ nframes64_t const frame = playhead_cursor->current_frame;
+
+ if (frame < leftmost_frame || frame > leftmost_frame + current_page_frames()) {
+
+ if (_session->transport_speed() < 0) {
+
+ if (frame > (current_page_frames() / 2)) {
+ center_screen (frame-(current_page_frames()/2));
+ } else {
+ center_screen (current_page_frames()/2);
+ }
+
+ } else {
+
+ if (frame < leftmost_frame) {
+ /* moving left */
+ nframes64_t l = 0;
+ if (_session->transport_rolling()) {
+ /* rolling; end up with the playhead at the right of the page */
+ l = frame - current_page_frames ();
+ } else {
+ /* not rolling: end up with the playhead 3/4 of the way along the page */
+ l = frame - (3 * current_page_frames() / 4);
+ }
+
+ if (l < 0) {
+ l = 0;
+ }
+
+ center_screen_internal (l + (current_page_frames() / 2), current_page_frames ());
+ } else {
+ /* moving right */
+ if (_session->transport_rolling()) {
+ /* rolling: end up with the playhead on the left of the page */
+ center_screen_internal (frame + (current_page_frames() / 2), current_page_frames ());
+ } else {
+ /* not rolling: end up with the playhead 1/4 of the way along the page */
+ center_screen_internal (frame + (current_page_frames() / 4), current_page_frames ());
+ }
+ }
+ }
+ }
+}
+
+void
+Editor::super_rapid_screen_update ()
+{
+ if (!_session || !_session->engine().running()) {
+ return;
+ }
+
+ /* METERING / MIXER STRIPS */
+
+ /* update track meters, if required */
+ if (is_mapped() && meters_running) {
+ RouteTimeAxisView* rtv;
+ for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
+ if ((rtv = dynamic_cast<RouteTimeAxisView*>(*i)) != 0) {
+ rtv->fast_update ();
+ }
+ }
+ }
+
+ /* and any current mixer strip */
+ if (current_mixer_strip) {
+ current_mixer_strip->fast_update ();
+ }
+
+ /* PLAYHEAD AND VIEWPORT */
+
+ nframes64_t const frame = _session->audible_frame();
+
+ /* There are a few reasons why we might not update the playhead / viewport stuff:
+ *
+ * 1. we don't update things when there's a pending locate request, otherwise
+ * when the editor requests a locate there is a chance that this method
+ * will move the playhead before the locate request is processed, causing
+ * 2. if we're not rolling, there's nothing to do here (locates are handled elsewhere).
+ * 3. if we're still at the same frame that we were last time, there's nothing to do.
+ */
+
+ if (!_pending_locate_request && _session->transport_speed() != 0 && frame != last_update_frame) {
+
+ last_update_frame = frame;
+
+ if (!_dragging_playhead) {
+ playhead_cursor->set_position (frame);
+ }
+
+ if (!_stationary_playhead) {
+
+ if (!_dragging_playhead && _follow_playhead && _session->requested_return_frame() < 0) {
+ reset_x_origin_to_follow_playhead ();
+ }
+
+ } else {
+
+ /* don't do continuous scroll till the new position is in the rightmost quarter of the
+ editor canvas
+ */
+#if 0
+ // FIXME DO SOMETHING THAT WORKS HERE - this is 2.X code
+ double target = ((double)frame - (double)current_page_frames()/2.0) / frames_per_unit;
+ if (target <= 0.0) {
+ target = 0.0;
+ }
+ if (fabs(target - current) < current_page_frames() / frames_per_unit) {
+ target = (target * 0.15) + (current * 0.85);
+ } else {
+ /* relax */
+ }
+
+ current = target;
+ horizontal_adjustment.set_value (current);
+#endif
+ }
+
+ }
+}
+
+
+void
+Editor::session_going_away ()
+{
+ _have_idled = false;
+
+ _session_connections.drop_connections ();
+
+ super_rapid_screen_update_connection.disconnect ();
+
+ selection->clear ();
+ cut_buffer->clear ();
+
+ clicked_regionview = 0;
+ clicked_axisview = 0;
+ clicked_routeview = 0;
+ clicked_crossfadeview = 0;
+ entered_regionview = 0;
+ entered_track = 0;
+ last_update_frame = 0;
+ _drags->abort ();
+
+ playhead_cursor->canvas_item.hide ();
+
+ /* rip everything out of the list displays */
+
+ _regions->clear ();
+ _routes->clear ();
+ _route_groups->clear ();
+
+ /* do this first so that deleting a track doesn't reset cms to null
+ and thus cause a leak.
+ */
+
+ if (current_mixer_strip) {
+ if (current_mixer_strip->get_parent() != 0) {
+ global_hpacker.remove (*current_mixer_strip);
+ }
+ delete current_mixer_strip;
+ current_mixer_strip = 0;
+ }
+
+ /* delete all trackviews */
+
+ for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
+ delete *i;
+ }
+ track_views.clear ();
+
+ zoom_range_clock.set_session (0);
+ nudge_clock.set_session (0);
+
+ editor_list_button.set_active(false);
+ editor_list_button.set_sensitive(false);
+
+ /* clear tempo/meter rulers */
+ remove_metric_marks ();
+ hide_measures ();
+ clear_marker_display ();
+
+ delete current_bbt_points;
+ current_bbt_points = 0;
+
+ /* get rid of any existing editor mixer strip */
+
+ WindowTitle title(Glib::get_application_name());
+ title += _("Editor");
+
+ set_title (title.get_string());
+
+ SessionHandlePtr::session_going_away ();
+}
+
+
+void
+Editor::show_editor_list (bool yn)
+{
+ if (yn) {
+ the_notebook.show();
+ } else {
+ the_notebook.hide();
+ }
+}