Increase mempool for session-scripts
[ardour.git] / libs / ardour / session.cc
index c207934534ceffcf5476839d1ab38ec677b43c79..2c3e1d2ef2f1b3c522583eab56d37d3526c2cd8b 100644 (file)
@@ -37,7 +37,6 @@
 
 #include "pbd/basename.h"
 #include "pbd/convert.h"
-#include "pbd/convert.h"
 #include "pbd/error.h"
 #include "pbd/file_utils.h"
 #include "pbd/md5.h"
@@ -82,6 +81,7 @@
 #include "ardour/midi_ui.h"
 #include "ardour/operations.h"
 #include "ardour/playlist.h"
+#include "ardour/playlist_factory.h"
 #include "ardour/plugin.h"
 #include "ardour/plugin_insert.h"
 #include "ardour/process_thread.h"
@@ -90,9 +90,9 @@
 #include "ardour/recent_sessions.h"
 #include "ardour/region.h"
 #include "ardour/region_factory.h"
+#include "ardour/revision.h"
 #include "ardour/route_graph.h"
 #include "ardour/route_group.h"
-#include "ardour/route_sorters.h"
 #include "ardour/send.h"
 #include "ardour/session.h"
 #include "ardour/session_directory.h"
 #include "ardour/user_bundle.h"
 #include "ardour/utils.h"
 #include "ardour/vca_manager.h"
+#include "ardour/vca.h"
 
 #include "midi++/port.h"
 #include "midi++/mmc.h"
 
 #include "LuaBridge/LuaBridge.h"
 
-#include "i18n.h"
+#include "pbd/i18n.h"
 
 #include <glibmm/checksum.h>
 
@@ -177,6 +178,7 @@ Session::Session (AudioEngine &eng,
        , _record_status (Disabled)
        , _transport_frame (0)
        , _session_range_location (0)
+       , _session_range_end_is_free (true)
        , _slave (0)
        , _silent (false)
        , _transport_speed (0)
@@ -211,13 +213,15 @@ Session::Session (AudioEngine &eng,
        , post_export_position (0)
        , _exporting (false)
        , _export_rolling (false)
+       , _realtime_export (false)
+       , _region_export (false)
        , _export_preroll (0)
+       , _export_latency (0)
        , _pre_export_mmc_enabled (false)
        , _name (snapshot_name)
        , _is_new (true)
        , _send_qf_mtc (false)
        , _pframes_since_last_mtc (0)
-       , session_midi_feedback (0)
        , play_loop (false)
        , loop_changing (false)
        , last_loopend (0)
@@ -236,7 +240,7 @@ Session::Session (AudioEngine &eng,
        , pending_locate_flush (false)
        , pending_abort (false)
        , pending_auto_loop (false)
-       , _mempool ("Session", 1048576)
+       , _mempool ("Session", 3145728)
        , lua (lua_newstate (&PBD::ReallocPool::lalloc, &_mempool))
        , _n_lua_scripts (0)
        , _butler (new Butler (*this))
@@ -247,11 +251,12 @@ Session::Session (AudioEngine &eng,
        , _ignore_skips_updates (false)
        , _rt_thread_active (false)
        , _rt_emit_pending (false)
-       , _ac_thread_active (false)
+       , _ac_thread_active (0)
+       , _latency_recompute_pending (0)
        , step_speed (0)
        , outbound_mtc_timecode_frame (0)
        , next_quarter_frame_to_send (-1)
-       , _frames_per_timecode_frame (0)
+       , _samples_per_timecode_frame (0)
        , _frames_per_hour (0)
        , _timecode_frames_per_hour (0)
        , last_timecode_valid (false)
@@ -295,9 +300,13 @@ Session::Session (AudioEngine &eng,
        , click_length (0)
        , click_emphasis_length (0)
        , _clicks_cleared (0)
+       , _count_in_samples (0)
        , _play_range (false)
        , _range_selection (-1,-1)
        , _object_selection (-1,-1)
+       , _preroll_record_punch_pos (-1)
+       , _preroll_record_trim_len (0)
+       , _count_in_once (false)
        , main_outs (0)
        , first_file_data_format_reset (true)
        , first_file_header_format_reset (true)
@@ -307,8 +316,7 @@ Session::Session (AudioEngine &eng,
        , _step_editors (0)
        , _suspend_timecode_transmission (0)
        ,  _speakers (new Speakers)
-       , _order_hint (-1)
-       , ignore_route_processor_changes (false)
+       , _ignore_route_processor_changes (0)
        , midi_clock (0)
        , _scene_changer (0)
        , _midi_ports (0)
@@ -317,6 +325,8 @@ Session::Session (AudioEngine &eng,
 {
        uint32_t sr = 0;
 
+       created_with = string_compose ("%1 %2", PROGRAM_NAME, revision);
+
        pthread_mutex_init (&_rt_emit_mutex, 0);
        pthread_cond_init (&_rt_emit_cond, 0);
 
@@ -324,8 +334,9 @@ Session::Session (AudioEngine &eng,
        pthread_cond_init (&_auto_connect_cond, 0);
 
        init_name_id_counter (1); // reset for new sessions, start at 1
+       VCA::set_next_vca_number (1); // reset for new sessions, start at 1
 
-       pre_engine_init (fullpath);
+       pre_engine_init (fullpath); // sets _is_new
 
        setup_lua ();
 
@@ -408,6 +419,8 @@ Session::Session (AudioEngine &eng,
 
        _state_of_the_state = StateOfTheState (_state_of_the_state & ~Dirty);
 
+       PresentationInfo::Change.connect_same_thread (*this, boost::bind (&Session::notify_presentation_info_change, this));
+
        Config->ParameterChanged.connect_same_thread (*this, boost::bind (&Session::config_changed, this, _1, false));
        config.ParameterChanged.connect_same_thread (*this, boost::bind (&Session::config_changed, this, _1, true));
 
@@ -471,6 +484,8 @@ Session::Session (AudioEngine &eng,
        }
 #endif
 
+       ensure_subdirs (); // archived or zipped sessions may lack peaks/ analysis/ etc
+
        _is_new = false;
        session_loaded ();
 
@@ -599,9 +614,6 @@ Session::destroy ()
 
        _state_of_the_state = StateOfTheState (CannotSave|Deletion);
 
-       /* stop autoconnecting */
-       auto_connect_thread_terminate ();
-
        /* disconnect from any and all signals that we are connected to */
 
        Port::PortSignalDrop (); /* EMIT SIGNAL */
@@ -613,6 +625,9 @@ Session::destroy ()
 
        ControlProtocolManager::instance().drop_protocols ();
 
+       /* stop autoconnecting */
+       auto_connect_thread_terminate ();
+
        MIDI::Name::MidiPatchManager::instance().remove_search_path(session_directory().midi_patch_path());
 
        _engine.remove_session ();
@@ -771,6 +786,7 @@ Session::destroy ()
                        case SessionEvent::Skip:
                        case SessionEvent::PunchIn:
                        case SessionEvent::PunchOut:
+                       case SessionEvent::RecordStart:
                        case SessionEvent::StopOnce:
                        case SessionEvent::RangeStop:
                        case SessionEvent::RangeLocate:
@@ -810,8 +826,10 @@ Session::setup_ltc ()
                {
                        Glib::Threads::Mutex::Lock lm (AudioEngine::instance()->process_lock ());
                        _ltc_input->ensure_io (ChanCount (DataType::AUDIO, 1), true, this);
+                       // TODO use auto-connect thread somehow (needs a route currently)
+                       // see note in Session::auto_connect_thread_run() why process lock is needed.
+                       reconnect_ltc_input ();
                }
-               reconnect_ltc_input ();
        }
 
        if (state_tree && (child = find_named_node (*state_tree->root(), X_("LTC Out"))) != 0) {
@@ -820,8 +838,9 @@ Session::setup_ltc ()
                {
                        Glib::Threads::Mutex::Lock lm (AudioEngine::instance()->process_lock ());
                        _ltc_output->ensure_io (ChanCount (DataType::AUDIO, 1), true, this);
+                       // TODO use auto-connect thread
+                       reconnect_ltc_output ();
                }
-               reconnect_ltc_output ();
        }
 
        /* fix up names of LTC ports because we don't want the normal
@@ -904,6 +923,14 @@ Session::setup_click_state (const XMLNode* node)
        }
 }
 
+void
+Session::get_physical_ports (vector<string>& inputs, vector<string>& outputs, DataType type,
+                             MidiPortFlags include, MidiPortFlags exclude)
+{
+       _engine.get_physical_inputs (type, inputs, include, exclude);
+       _engine.get_physical_outputs (type, outputs, include, exclude);
+}
+
 void
 Session::setup_bundles ()
 {
@@ -922,9 +949,12 @@ Session::setup_bundles ()
 
        vector<string> inputs[DataType::num_types];
        vector<string> outputs[DataType::num_types];
+
        for (uint32_t i = 0; i < DataType::num_types; ++i) {
-               _engine.get_physical_inputs (DataType (DataType::Symbol (i)), inputs[i]);
-               _engine.get_physical_outputs (DataType (DataType::Symbol (i)), outputs[i]);
+               get_physical_ports (inputs[i], outputs[i], DataType (DataType::Symbol (i)),
+                                   MidiPortFlags (0), /* no specific inclusions */
+                                   MidiPortFlags (MidiPortControl|MidiPortVirtual) /* exclude control & virtual ports */
+                       );
        }
 
        /* Create a set of Bundle objects that map
@@ -1008,6 +1038,7 @@ Session::setup_bundles ()
 
        for (uint32_t np = 0; np < inputs[DataType::MIDI].size(); ++np) {
                string n = inputs[DataType::MIDI][np];
+
                std::string pn = _engine.get_pretty_name_by_name (n);
                if (!pn.empty()) {
                        n = pn;
@@ -1110,7 +1141,7 @@ Session::remove_monitor_section ()
 
 
                boost::shared_ptr<RouteList> r = routes.reader ();
-               PBD::Unwinder<bool> uw (ignore_route_processor_changes, true);
+               ProcessorChangeBlocker  pcb (this, false);
 
                for (RouteList::iterator x = r->begin(); x != r->end(); ++x) {
 
@@ -1147,7 +1178,7 @@ Session::add_monitor_section ()
                return;
        }
 
-       boost::shared_ptr<Route> r (new Route (*this, _("Monitor"), Route::MonitorOut, DataType::AUDIO));
+       boost::shared_ptr<Route> r (new Route (*this, _("Monitor"), PresentationInfo::MonitorOut, DataType::AUDIO));
 
        if (r->init ()) {
                return;
@@ -1165,7 +1196,7 @@ Session::add_monitor_section ()
        }
 
        rl.push_back (r);
-       add_routes (rl, false, false, false);
+       add_routes (rl, false, false, false, 0);
 
        assert (_monitor_out);
 
@@ -1270,7 +1301,7 @@ Session::add_monitor_section ()
 
        boost::shared_ptr<RouteList> rls = routes.reader ();
 
-       PBD::Unwinder<bool> uw (ignore_route_processor_changes, true);
+       ProcessorChangeBlocker  pcb (this, false /* XXX */);
 
        for (RouteList::iterator x = rls->begin(); x != rls->end(); ++x) {
 
@@ -1311,8 +1342,12 @@ Session::reset_monitor_section ()
        _master_out->output()->disconnect (this);
        _monitor_out->output()->disconnect (this);
 
-       _monitor_out->input()->ensure_io (_master_out->output()->n_ports(), false, this);
-       _monitor_out->output()->ensure_io (_master_out->output()->n_ports(), false, this);
+       // monitor section follow master bus - except midi
+       ChanCount mon_chn (_master_out->output()->n_ports());
+       mon_chn.set_midi (0);
+
+       _monitor_out->input()->ensure_io (mon_chn, false, this);
+       _monitor_out->output()->ensure_io (mon_chn, false, this);
 
        for (uint32_t n = 0; n < limit; ++n) {
                boost::shared_ptr<AudioPort> p = _monitor_out->input()->ports().nth_audio_port (n);
@@ -1390,7 +1425,7 @@ Session::reset_monitor_section ()
 
        boost::shared_ptr<RouteList> rls = routes.reader ();
 
-       PBD::Unwinder<bool> uw (ignore_route_processor_changes, true);
+       ProcessorChangeBlocker pcb (this, false);
 
        for (RouteList::iterator x = rls->begin(); x != rls->end(); ++x) {
 
@@ -1653,7 +1688,7 @@ Session::set_session_extents (framepos_t start, framepos_t end)
        Location* existing;
        if ((existing = _locations->session_range_location()) == 0) {
                //if there is no existing session, we need to make a new session location  (should never happen)
-               existing = new Location (*this, 0, 0, _("session"), Location::IsSessionRange);
+               existing = new Location (*this, 0, 0, _("session"), Location::IsSessionRange, 0);
        }
 
        if (end <= start) {
@@ -1842,6 +1877,17 @@ Session::location_added (Location *location)
                 location->EndChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
                 location->Changed.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
                 location->FlagsChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
+               location->PositionLockStyleChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
+        }
+
+       if (location->is_range_marker()) {
+                /* listen for per-location signals that require us to do any * global updates for marks */
+
+                location->StartChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
+                location->EndChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
+                location->Changed.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
+                location->FlagsChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
+               location->PositionLockStyleChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
         }
 
         if (location->is_skip()) {
@@ -1851,6 +1897,7 @@ Session::location_added (Location *location)
                 location->EndChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_skips, this, location, true));
                 location->Changed.connect_same_thread (skip_update_connections, boost::bind (&Session::update_skips, this, location, true));
                 location->FlagsChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_skips, this, location, false));
+               location->PositionLockStyleChanged.connect_same_thread (skip_update_connections, boost::bind (&Session::update_marks, this, location));
 
                 update_skips (location, true);
         }
@@ -1942,7 +1989,7 @@ void
 Session::set_all_tracks_record_enabled (bool enable )
 {
        boost::shared_ptr<RouteList> rl = routes.reader();
-       set_controls (route_list_to_control_list (rl, &Track::rec_enable_control), enable, Controllable::NoGroup);
+       set_controls (route_list_to_control_list (rl, &Stripable::rec_enable_control), enable, Controllable::NoGroup);
 }
 
 void
@@ -1970,6 +2017,7 @@ Session::disable_record (bool rt_context, bool force)
                if (!rt_context) {
                        remove_pending_capture_state ();
                }
+               unset_preroll_record_punch ();
        }
 }
 
@@ -1987,7 +2035,7 @@ Session::step_back_from_record ()
 }
 
 void
-Session::maybe_enable_record ()
+Session::maybe_enable_record (bool rt_context)
 {
        if (_step_editors > 0) {
                return;
@@ -1996,15 +2044,18 @@ Session::maybe_enable_record ()
        g_atomic_int_set (&_record_status, Enabled);
 
        /* This function is currently called from somewhere other than an RT thread.
-          This save_state() call therefore doesn't impact anything.  Doing it here
-          means that we save pending state of which sources the next record will use,
-          which gives us some chance of recovering from a crash during the record.
-       */
+        * (except maybe lua scripts, which can use rt_context = true)
+        * This save_state() call therefore doesn't impact anything.  Doing it here
+        * means that we save pending state of which sources the next record will use,
+        * which gives us some chance of recovering from a crash during the record.
+        */
 
-       save_state ("", true);
+       if (!rt_context) {
+               save_state ("", true);
+       }
 
        if (_transport_speed) {
-               if (!config.get_punch_in()) {
+               if (!config.get_punch_in() && !preroll_record_punch_enabled ()) {
                        enable_record ();
                }
        } else {
@@ -2019,59 +2070,71 @@ framepos_t
 Session::audible_frame () const
 {
        framepos_t ret;
-       framepos_t tf;
-       framecnt_t offset;
 
-       offset = worst_playback_latency ();
+       frameoffset_t offset = worst_playback_latency (); // - _engine.samples_since_cycle_start ();
+       offset *= transport_speed ();
 
        if (synced_to_engine()) {
                /* Note: this is basically just sync-to-JACK */
-               tf = _engine.transport_frame();
+               ret = _engine.transport_frame();
        } else {
-               tf = _transport_frame;
+               ret = _transport_frame;
        }
 
-       ret = tf;
-
-       if (!non_realtime_work_pending()) {
-
-               /* MOVING */
+       if (transport_rolling()) {
+               ret -= offset;
 
                /* Check to see if we have passed the first guaranteed
-                  audible frame past our last start position. if not,
-                  return that last start point because in terms
-                  of audible frames, we have not moved yet.
-
-                  `Start position' in this context means the time we last
-                  either started, located, or changed transport direction.
-               */
+                * audible frame past our last start position. if not,
+                * return that last start point because in terms
+                * of audible frames, we have not moved yet.
+                *
+                * `Start position' in this context means the time we last
+                * either started, located, or changed transport direction.
+                */
 
                if (_transport_speed > 0.0f) {
 
                        if (!play_loop || !have_looped) {
-                               if (tf < _last_roll_or_reversal_location + offset) {
+                               if (ret < _last_roll_or_reversal_location) {
                                        return _last_roll_or_reversal_location;
                                }
+                       } else {
+                               // latent loops
+                               Location *location = _locations->auto_loop_location();
+                               frameoffset_t lo = location->start() - ret;
+                               if (lo > 0) {
+                                       ret = location->end () - lo;
+                               }
                        }
 
-
-                       /* forwards */
-                       ret -= offset;
-
                } else if (_transport_speed < 0.0f) {
 
                        /* XXX wot? no backward looping? */
 
-                       if (tf > _last_roll_or_reversal_location - offset) {
+                       if (ret > _last_roll_or_reversal_location) {
                                return _last_roll_or_reversal_location;
-                       } else {
-                               /* backwards */
-                               ret += offset;
                        }
                }
        }
 
-       return ret;
+       return std::max ((framepos_t)0, ret);
+}
+
+
+framecnt_t
+Session::preroll_samples (framepos_t pos) const
+{
+       const float pr = Config->get_preroll_seconds();
+       if (pos >= 0 && pr < 0) {
+               const Tempo& tempo = _tempo_map->tempo_at_frame (pos);
+               const Meter& meter = _tempo_map->meter_at_frame (pos);
+               return meter.frames_per_bar (tempo, frame_rate()) * -pr;
+       }
+       if (pr < 0) {
+               return 0;
+       }
+       return pr * frame_rate();
 }
 
 void
@@ -2305,8 +2368,7 @@ Session::resort_routes_using (boost::shared_ptr<RouteList> r)
 #ifndef NDEBUG
                DEBUG_TRACE (DEBUG::Graph, "Routes resorted, order follows:\n");
                for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
-                       DEBUG_TRACE (DEBUG::Graph, string_compose ("\t%1 signal order %2\n",
-                                                                  (*i)->name(), (*i)->order_key ()));
+                       DEBUG_TRACE (DEBUG::Graph, string_compose ("\t%1 presentation order %2\n", (*i)->name(), (*i)->presentation_info().order()));
                }
 #endif
 
@@ -2347,12 +2409,12 @@ Session::find_route_name (string const & base, uint32_t& id, string& name, bool
           before anything else.
        */
 
-       for (vector<string>::const_iterator reserved = reserved_io_names.begin(); reserved != reserved_io_names.end(); ++reserved) {
-               if (base == *reserved) {
+       for (map<string,bool>::const_iterator reserved = reserved_io_names.begin(); reserved != reserved_io_names.end(); ++reserved) {
+               if (base == reserved->first) {
                        /* Check if this reserved name already exists, and if
                           so, disallow it without a numeric suffix.
                        */
-                       if (route_by_name (*reserved)) {
+                       if (!reserved->second || route_by_name (reserved->first)) {
                                definitely_add_number = true;
                                if (id < 1) {
                                        id = 1;
@@ -2362,8 +2424,11 @@ Session::find_route_name (string const & base, uint32_t& id, string& name, bool
                }
        }
 
-       if (!definitely_add_number && route_by_name (base) == 0) {
-               /* juse use the base */
+       /* if we have "base 1" already, it doesn't make sense to add "base"
+        * if "base 1" has been deleted, adding "base" is no worse than "base 1"
+        */
+       if (!definitely_add_number && route_by_name (base) == 0 && (route_by_name (string_compose("%1 1", base)) == 0)) {
+               /* just use the base */
                name = base;
                return true;
        }
@@ -2424,8 +2489,11 @@ Session::default_track_name_pattern (DataType t)
  *  @param instrument plugin info for the instrument to insert pre-fader, if any
  */
 list<boost::shared_ptr<MidiTrack> >
-Session::new_midi_track (const ChanCount& input, const ChanCount& output, boost::shared_ptr<PluginInfo> instrument,
-                        TrackMode mode, RouteGroup* route_group, uint32_t how_many, string name_template, Plugin::PresetRecord* pset)
+Session::new_midi_track (const ChanCount& input, const ChanCount& output, bool strict_io,
+                         boost::shared_ptr<PluginInfo> instrument, Plugin::PresetRecord* pset,
+                         RouteGroup* route_group, uint32_t how_many,
+                         string name_template, PresentationInfo::order_t order,
+                         TrackMode mode)
 {
        string track_name;
        uint32_t track_id = 0;
@@ -2445,13 +2513,13 @@ Session::new_midi_track (const ChanCount& input, const ChanCount& output, boost:
                boost::shared_ptr<MidiTrack> track;
 
                try {
-                       track.reset (new MidiTrack (*this, track_name, Route::Flag (0), mode));
+                       track.reset (new MidiTrack (*this, track_name, mode));
 
                        if (track->init ()) {
                                goto failed;
                        }
 
-                       if (Profile->get_mixbus ()) {
+                       if (strict_io) {
                                track->set_strict_io (true);
                        }
 
@@ -2480,14 +2548,8 @@ Session::new_midi_track (const ChanCount& input, const ChanCount& output, boost:
 
                        track->DiskstreamChanged.connect_same_thread (*this, boost::bind (&Session::resort_routes, this));
 
-                       if (Config->get_remote_model() == UserOrdered) {
-                               track->set_remote_control_id (next_control_id());
-                       }
-
                        new_routes.push_back (track);
                        ret.push_back (track);
-
-                       RouteAddedOrRemoved (true); /* EMIT SIGNAL */
                }
 
                catch (failed_constructor &err) {
@@ -2508,20 +2570,31 @@ Session::new_midi_track (const ChanCount& input, const ChanCount& output, boost:
        if (!new_routes.empty()) {
                StateProtector sp (this);
                if (Profile->get_trx()) {
-                       add_routes (new_routes, false, false, false);
+                       add_routes (new_routes, false, false, false, order);
                } else {
-                       add_routes (new_routes, true, true, false);
+                       add_routes (new_routes, true, true, false, order);
                }
 
                if (instrument) {
                        for (RouteList::iterator r = new_routes.begin(); r != new_routes.end(); ++r) {
                                PluginPtr plugin = instrument->load (*this);
+                               if (!plugin) {
+                                       warning << "Failed to add Synth Plugin to newly created track." << endmsg;
+                                       continue;
+                               }
                                if (pset) {
                                        plugin->load_preset (*pset);
                                }
-                               boost::shared_ptr<Processor> p (new PluginInsert (*this, plugin));
-                               (*r)->add_processor (p, PreFader);
+                               boost::shared_ptr<PluginInsert> pi (new PluginInsert (*this, plugin));
+                               if (strict_io) {
+                                       pi->set_strict_io (true);
+                               }
+
+                               (*r)->add_processor (pi, PreFader);
 
+                               if (Profile->get_mixbus () && pi->configured () && pi->output_streams().n_audio() > 2) {
+                                       (*r)->move_instrument_down (false);
+                               }
                        }
                }
        }
@@ -2530,7 +2603,9 @@ Session::new_midi_track (const ChanCount& input, const ChanCount& output, boost:
 }
 
 RouteList
-Session::new_midi_route (RouteGroup* route_group, uint32_t how_many, string name_template, boost::shared_ptr<PluginInfo> instrument, Plugin::PresetRecord* pset)
+Session::new_midi_route (RouteGroup* route_group, uint32_t how_many, string name_template, bool strict_io,
+                         boost::shared_ptr<PluginInfo> instrument, Plugin::PresetRecord* pset,
+                         PresentationInfo::Flag flag, PresentationInfo::order_t order)
 {
        string bus_name;
        uint32_t bus_id = 0;
@@ -2546,13 +2621,13 @@ Session::new_midi_route (RouteGroup* route_group, uint32_t how_many, string name
                }
 
                try {
-                       boost::shared_ptr<Route> bus (new Route (*this, bus_name, Route::Flag(0), DataType::AUDIO)); // XXX Editor::add_routes is not ready for ARDOUR::DataType::MIDI
+                       boost::shared_ptr<Route> bus (new Route (*this, bus_name, flag, DataType::AUDIO)); // XXX Editor::add_routes is not ready for ARDOUR::DataType::MIDI
 
                        if (bus->init ()) {
                                goto failure;
                        }
 
-                       if (Profile->get_mixbus ()) {
+                       if (strict_io) {
                                bus->set_strict_io (true);
                        }
 
@@ -2576,13 +2651,9 @@ Session::new_midi_route (RouteGroup* route_group, uint32_t how_many, string name
                        if (route_group) {
                                route_group->add (bus);
                        }
-                       if (Config->get_remote_model() == UserOrdered) {
-                               bus->set_remote_control_id (next_control_id());
-                       }
 
+                       bus->add_internal_return ();
                        ret.push_back (bus);
-                       RouteAddedOrRemoved (true); /* EMIT SIGNAL */
-                       ARDOUR::GUIIdle ();
                }
 
                catch (failed_constructor &err) {
@@ -2602,16 +2673,28 @@ Session::new_midi_route (RouteGroup* route_group, uint32_t how_many, string name
   failure:
        if (!ret.empty()) {
                StateProtector sp (this);
-               add_routes (ret, false, false, false);
+               add_routes (ret, false, false, false, order);
 
                if (instrument) {
                        for (RouteList::iterator r = ret.begin(); r != ret.end(); ++r) {
                                PluginPtr plugin = instrument->load (*this);
+                               if (!plugin) {
+                                       warning << "Failed to add Synth Plugin to newly created track." << endmsg;
+                                       continue;
+                               }
                                if (pset) {
                                        plugin->load_preset (*pset);
                                }
-                               boost::shared_ptr<Processor> p (new PluginInsert (*this, plugin));
-                               (*r)->add_processor (p, PreFader);
+                               boost::shared_ptr<PluginInsert> pi (new PluginInsert (*this, plugin));
+                               if (strict_io) {
+                                       pi->set_strict_io (true);
+                               }
+
+                               (*r)->add_processor (pi, PreFader);
+
+                               if (Profile->get_mixbus () && pi->configured () && pi->output_streams().n_audio() > 2) {
+                                       (*r)->move_instrument_down (false);
+                               }
                        }
                }
        }
@@ -2929,12 +3012,40 @@ Session::reconnect_mmc_ports(bool inputs)
 
 #endif
 
+void
+Session::ensure_route_presentation_info_gap (PresentationInfo::order_t first_new_order, uint32_t how_many)
+{
+       if (first_new_order == PresentationInfo::max_order) {
+               /* adding at end, no worries */
+               return;
+       }
+
+       /* create a gap in the presentation info to accomodate @param how_many
+        * new objects.
+        */
+       StripableList sl;
+       get_stripables (sl);
+
+       for (StripableList::iterator si = sl.begin(); si != sl.end(); ++si) {
+               boost::shared_ptr<Stripable> s (*si);
+
+               if (s->is_monitor() || s->is_auditioner()) {
+                       continue;
+               }
+
+               if (s->presentation_info().order () >= first_new_order) {
+                       s->set_presentation_order (s->presentation_info().order () + how_many);
+               }
+       }
+}
+
 /** Caller must not hold process lock
  *  @param name_template string to use for the start of the name, or "" to use "Audio".
  */
 list< boost::shared_ptr<AudioTrack> >
-Session::new_audio_track (int input_channels, int output_channels, TrackMode mode, RouteGroup* route_group,
-                         uint32_t how_many, string name_template)
+Session::new_audio_track (int input_channels, int output_channels, RouteGroup* route_group,
+                          uint32_t how_many, string name_template, PresentationInfo::order_t order,
+                          TrackMode mode)
 {
        string track_name;
        uint32_t track_id = 0;
@@ -2955,7 +3066,7 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
                boost::shared_ptr<AudioTrack> track;
 
                try {
-                       track.reset (new AudioTrack (*this, track_name, Route::Flag (0), mode));
+                       track.reset (new AudioTrack (*this, track_name, mode));
 
                        if (track->init ()) {
                                goto failed;
@@ -2965,7 +3076,6 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
                                track->set_strict_io (true);
                        }
 
-
                        if (ARDOUR::Profile->get_trx ()) {
                                // TRACKS considers it's not a USE CASE, it's
                                // a piece of behavior of the session model:
@@ -3011,14 +3121,9 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
                        track->non_realtime_input_change();
 
                        track->DiskstreamChanged.connect_same_thread (*this, boost::bind (&Session::resort_routes, this));
-                       if (Config->get_remote_model() == UserOrdered) {
-                               track->set_remote_control_id (next_control_id());
-                       }
 
                        new_routes.push_back (track);
                        ret.push_back (track);
-
-                       RouteAddedOrRemoved (true); /* EMIT SIGNAL */
                }
 
                catch (failed_constructor &err) {
@@ -3039,9 +3144,9 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
        if (!new_routes.empty()) {
                StateProtector sp (this);
                if (Profile->get_trx()) {
-                       add_routes (new_routes, false, false, false);
+                       add_routes (new_routes, false, false, false, order);
                } else {
-                       add_routes (new_routes, true, true, false);
+                       add_routes (new_routes, true, true, false, order);
                }
        }
 
@@ -3052,7 +3157,8 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
  *  @param name_template string to use for the start of the name, or "" to use "Bus".
  */
 RouteList
-Session::new_audio_route (int input_channels, int output_channels, RouteGroup* route_group, uint32_t how_many, string name_template)
+Session::new_audio_route (int input_channels, int output_channels, RouteGroup* route_group, uint32_t how_many, string name_template,
+                          PresentationInfo::Flag flags, PresentationInfo::order_t order)
 {
        string bus_name;
        uint32_t bus_id = 0;
@@ -3068,7 +3174,7 @@ Session::new_audio_route (int input_channels, int output_channels, RouteGroup* r
                }
 
                try {
-                       boost::shared_ptr<Route> bus (new Route (*this, bus_name, Route::Flag(0), DataType::AUDIO));
+                       boost::shared_ptr<Route> bus (new Route (*this, bus_name, flags, DataType::AUDIO));
 
                        if (bus->init ()) {
                                goto failure;
@@ -3102,20 +3208,11 @@ Session::new_audio_route (int input_channels, int output_channels, RouteGroup* r
                        if (route_group) {
                                route_group->add (bus);
                        }
-                       if (Config->get_remote_model() == UserOrdered) {
-                               bus->set_remote_control_id (next_control_id());
-                       }
 
                        bus->add_internal_return ();
-
                        ret.push_back (bus);
-
-                       RouteAddedOrRemoved (true); /* EMIT SIGNAL */
-
-                       ARDOUR::GUIIdle ();
                }
 
-
                catch (failed_constructor &err) {
                        error << _("Session: could not create new audio route.") << endmsg;
                        goto failure;
@@ -3134,9 +3231,9 @@ Session::new_audio_route (int input_channels, int output_channels, RouteGroup* r
        if (!ret.empty()) {
                StateProtector sp (this);
                if (Profile->get_trx()) {
-                       add_routes (ret, false, false, false);
+                       add_routes (ret, false, false, false, order);
                } else {
-                       add_routes (ret, false, true, true); // autoconnect // outputs only
+                       add_routes (ret, false, true, true, order); // autoconnect // outputs only
                }
        }
 
@@ -3145,7 +3242,8 @@ Session::new_audio_route (int input_channels, int output_channels, RouteGroup* r
 }
 
 RouteList
-Session::new_route_from_template (uint32_t how_many, const std::string& template_path, const std::string& name_base, PlaylistDisposition pd)
+Session::new_route_from_template (uint32_t how_many, PresentationInfo::order_t insert_at, const std::string& template_path, const std::string& name_base,
+                                  PlaylistDisposition pd)
 {
        XMLTree tree;
 
@@ -3153,14 +3251,13 @@ Session::new_route_from_template (uint32_t how_many, const std::string& template
                return RouteList();
        }
 
-       return new_route_from_template (how_many, *tree.root(), name_base, pd);
+       return new_route_from_template (how_many, insert_at, *tree.root(), name_base, pd);
 }
 
 RouteList
-Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::string& name_base, PlaylistDisposition pd)
+Session::new_route_from_template (uint32_t how_many, PresentationInfo::order_t insert_at, XMLNode& node, const std::string& name_base, PlaylistDisposition pd)
 {
        RouteList ret;
-       uint32_t control_id;
        uint32_t number = 0;
        const uint32_t being_added = how_many;
        /* This will prevent the use of any existing XML-provided PBD::ID
@@ -3169,8 +3266,6 @@ Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::s
        Stateful::ForceIDRegeneration force_ids;
        IO::disable_connecting ();
 
-       control_id = next_control_id ();
-
        while (how_many) {
 
                /* We're going to modify the node contents a bit so take a
@@ -3207,17 +3302,27 @@ Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::s
 
                        /* set this name in the XML description that we are about to use */
 
-                       bool rename_playlist;
-                       switch (pd) {
-                       case NewPlaylist:
-                               rename_playlist = true;
-                               break;
-                       default:
-                       case CopyPlaylist:
-                       case SharePlaylist:
-                               rename_playlist = false;
+                       if (pd == CopyPlaylist) {
+                               XMLNode* ds_node = find_named_node (node_copy, "Diskstream");
+                               if (ds_node) {
+                                       const std::string playlist_name = ds_node->property (X_("playlist"))->value ();
+                                       boost::shared_ptr<Playlist> playlist = playlists->by_name (playlist_name);
+                                       // Use same name as Route::set_name_in_state so playlist copy
+                                       // is picked up when creating the Route in XMLRouteFactory below
+                                       playlist = PlaylistFactory::create (playlist, string_compose ("%1.1", name));
+                                       playlist->reset_shares ();
+                               }
+                       } else if (pd == SharePlaylist) {
+                               XMLNode* ds_node = find_named_node (node_copy, "Diskstream");
+                               if (ds_node) {
+                                       const std::string playlist_name = ds_node->property (X_("playlist"))->value ();
+                                       boost::shared_ptr<Playlist> playlist = playlists->by_name (playlist_name);
+                                       playlist->share_with ((node_copy.property (X_("id")))->value());
+                               }
                        }
 
+                       bool rename_playlist = (pd == CopyPlaylist || pd == NewPlaylist);
+
                        Route::set_name_in_state (node_copy, name, rename_playlist);
 
                        /* trim bitslots from listen sends so that new ones are used */
@@ -3257,6 +3362,10 @@ Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::s
                                                (*i)->add_property ("bitslot", buf);
                                                (*i)->add_property ("name", name);
                                        }
+                                       else if (type && type->value() == X_("intreturn")) {
+                                               (*i)->remove_property (X_("bitslot"));
+                                               (*i)->add_property ("ignore-bitslot", "1");
+                                       }
                                        else if (type && type->value() == X_("return")) {
                                                // Return::set_state() generates a new one
                                                (*i)->remove_property (X_("bitslot"));
@@ -3291,27 +3400,7 @@ Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::s
                                route->output()->changed (change, this);
                        }
 
-                       route->set_remote_control_id (control_id);
-                       ++control_id;
-
-                       boost::shared_ptr<Track> track;
-
-                       if ((track = boost::dynamic_pointer_cast<Track> (route))) {
-                               switch (pd) {
-                               case NewPlaylist:
-                                       track->use_new_playlist ();
-                                       break;
-                               case CopyPlaylist:
-                                       track->use_copy_playlist ();
-                                       break;
-                               case SharePlaylist:
-                                       break;
-                               }
-                       };
-
                        ret.push_back (route);
-
-                       RouteAddedOrRemoved (true); /* EMIT SIGNAL */
                }
 
                catch (failed_constructor &err) {
@@ -3331,9 +3420,9 @@ Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::s
        if (!ret.empty()) {
                StateProtector sp (this);
                if (Profile->get_trx()) {
-                       add_routes (ret, false, false, false);
+                       add_routes (ret, false, false, false, insert_at);
                } else {
-                       add_routes (ret, true, true, false);
+                       add_routes (ret, true, true, false, insert_at);
                }
                IO::enable_connecting ();
        }
@@ -3342,11 +3431,11 @@ Session::new_route_from_template (uint32_t how_many, XMLNode& node, const std::s
 }
 
 void
-Session::add_routes (RouteList& new_routes, bool input_auto_connect, bool output_auto_connect, bool save)
+Session::add_routes (RouteList& new_routes, bool input_auto_connect, bool output_auto_connect, bool save, PresentationInfo::order_t order)
 {
        try {
                PBD::Unwinder<bool> aip (_adding_routes_in_progress, true);
-               add_routes_inner (new_routes, input_auto_connect, output_auto_connect);
+               add_routes_inner (new_routes, input_auto_connect, output_auto_connect, order);
 
        } catch (...) {
                error << _("Adding new tracks/busses failed") << endmsg;
@@ -3363,25 +3452,18 @@ Session::add_routes (RouteList& new_routes, bool input_auto_connect, bool output
                save_state (_current_snapshot_name);
        }
 
-       reassign_track_numbers();
-
        update_route_record_state ();
 
        RouteAdded (new_routes); /* EMIT SIGNAL */
 }
 
 void
-Session::add_routes_inner (RouteList& new_routes, bool input_auto_connect, bool output_auto_connect)
+Session::add_routes_inner (RouteList& new_routes, bool input_auto_connect, bool output_auto_connect, PresentationInfo::order_t order)
 {
        ChanCount existing_inputs;
        ChanCount existing_outputs;
-       uint32_t order = next_control_id();
-
-
-       if (_order_hint > -1) {
-               order = _order_hint;
-               _order_hint = -1;
-       }
+       uint32_t n_routes;
+       uint32_t added = 0;
 
        count_existing_track_channels (existing_inputs, existing_outputs);
 
@@ -3389,6 +3471,7 @@ Session::add_routes_inner (RouteList& new_routes, bool input_auto_connect, bool
                RCUWriter<RouteList> writer (routes);
                boost::shared_ptr<RouteList> r = writer.get_copy ();
                r->insert (r->end(), new_routes.begin(), new_routes.end());
+               n_routes = r->size();
 
                /* if there is no control out and we're not in the middle of loading,
                 * resort the graph here. if there is a control out, we will resort
@@ -3401,62 +3484,109 @@ Session::add_routes_inner (RouteList& new_routes, bool input_auto_connect, bool
                }
        }
 
-       for (RouteList::iterator x = new_routes.begin(); x != new_routes.end(); ++x) {
+       /* auditioner and monitor routes are not part of the order */
+       if (auditioner) {
+               assert (n_routes > 0);
+               --n_routes;
+       }
+       if (_monitor_out) {
+               assert (n_routes > 0);
+               --n_routes;
+       }
 
-               boost::weak_ptr<Route> wpr (*x);
-               boost::shared_ptr<Route> r (*x);
+       DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("ensure order gap starting at %1 for %2\n", order, new_routes.size()));
+       ensure_route_presentation_info_gap (order, new_routes.size());
 
-               r->solo_control()->Changed.connect_same_thread (*this, boost::bind (&Session::route_solo_changed, this, _1, _2,wpr));
-               r->solo_isolate_control()->Changed.connect_same_thread (*this, boost::bind (&Session::route_solo_isolated_changed, this, wpr));
-               r->mute_control()->Changed.connect_same_thread (*this, boost::bind (&Session::route_mute_changed, this));
+       {
+               PresentationInfo::ChangeSuspender cs;
 
-               r->output()->changed.connect_same_thread (*this, boost::bind (&Session::set_worst_io_latencies_x, this, _1, _2));
-               r->processors_changed.connect_same_thread (*this, boost::bind (&Session::route_processors_changed, this, _1));
+               for (RouteList::iterator x = new_routes.begin(); x != new_routes.end(); ++x, ++added) {
 
-               if (r->is_master()) {
-                       _master_out = r;
-               }
+                       boost::weak_ptr<Route> wpr (*x);
+                       boost::shared_ptr<Route> r (*x);
 
-               if (r->is_monitor()) {
-                       _monitor_out = r;
-               }
+                       r->solo_control()->Changed.connect_same_thread (*this, boost::bind (&Session::route_solo_changed, this, _1, _2,wpr));
+                       r->solo_isolate_control()->Changed.connect_same_thread (*this, boost::bind (&Session::route_solo_isolated_changed, this, wpr));
+                       r->mute_control()->Changed.connect_same_thread (*this, boost::bind (&Session::route_mute_changed, this));
 
-               boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (r);
-               if (tr) {
-                       tr->PlaylistChanged.connect_same_thread (*this, boost::bind (&Session::track_playlist_changed, this, boost::weak_ptr<Track> (tr)));
-                       track_playlist_changed (boost::weak_ptr<Track> (tr));
-                       tr->rec_enable_control()->Changed.connect_same_thread (*this, boost::bind (&Session::update_route_record_state, this));
-
-                       boost::shared_ptr<MidiTrack> mt = boost::dynamic_pointer_cast<MidiTrack> (tr);
-                       if (mt) {
-                               mt->StepEditStatusChange.connect_same_thread (*this, boost::bind (&Session::step_edit_status_change, this, _1));
-                               mt->output()->changed.connect_same_thread (*this, boost::bind (&Session::midi_output_change_handler, this, _1, _2, boost::weak_ptr<Route>(mt)));
+                       r->output()->changed.connect_same_thread (*this, boost::bind (&Session::set_worst_io_latencies_x, this, _1, _2));
+                       r->processors_changed.connect_same_thread (*this, boost::bind (&Session::route_processors_changed, this, _1));
+                       r->processor_latency_changed.connect_same_thread (*this, boost::bind (&Session::queue_latency_recompute, this));
+
+                       if (r->is_master()) {
+                               _master_out = r;
                        }
-               }
 
-               if (input_auto_connect || output_auto_connect) {
-                       auto_connect_route (r, input_auto_connect, ChanCount (), ChanCount (), existing_inputs, existing_outputs);
-                       existing_inputs += r->n_inputs();
-                       existing_outputs += r->n_outputs();
-               }
+                       if (r->is_monitor()) {
+                               _monitor_out = r;
+                       }
+
+                       boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (r);
+                       if (tr) {
+                               tr->PlaylistChanged.connect_same_thread (*this, boost::bind (&Session::track_playlist_changed, this, boost::weak_ptr<Track> (tr)));
+                               track_playlist_changed (boost::weak_ptr<Track> (tr));
+                               tr->rec_enable_control()->Changed.connect_same_thread (*this, boost::bind (&Session::update_route_record_state, this));
+
+                               boost::shared_ptr<MidiTrack> mt = boost::dynamic_pointer_cast<MidiTrack> (tr);
+                               if (mt) {
+                                       mt->StepEditStatusChange.connect_same_thread (*this, boost::bind (&Session::step_edit_status_change, this, _1));
+                                       mt->output()->changed.connect_same_thread (*this, boost::bind (&Session::midi_output_change_handler, this, _1, _2, boost::weak_ptr<Route>(mt)));
+                                       mt->presentation_info().PropertyChanged.connect_same_thread (*this, boost::bind (&Session::midi_track_presentation_info_changed, this, _1, boost::weak_ptr<MidiTrack>(mt)));
+                               }
+                       }
+
+                       if (!r->presentation_info().special()) {
+
+                               DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("checking PI state for %1\n", r->name()));
+
+                               /* presentation info order may already have been set from XML */
+
+                               if (!r->presentation_info().order_set()) {
+                                       /* this is only useful for headless sessions,
+                                        * Editor::add_routes() and Mixer_UI::add_routes() will
+                                        * override it following the RouteAdded signal.
+                                        *
+                                        * Also routes should be sorted before VCAs (like the GUI does).
+                                        * Session::ensure_route_presentation_info_gap() does not special case VCAs either.
+                                        *
+                                        * ... but not to worry, the GUI's
+                                        * gtk2_ardour/route_sorter.h and various ::sync_presentation_info_from_treeview()
+                                        * handle this :)
+                                        */
 
-               /* order keys are a GUI responsibility but we need to set up
-                        reasonable defaults because they also affect the remote control
-                        ID in most situations.
+                                       if (order == PresentationInfo::max_order) {
+                                               /* just add to the end */
+                                               r->set_presentation_order (n_routes + added);
+                                               DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("group order not set, set to NR %1 + %2 = %3\n", n_routes, added, n_routes + added));
+                                       } else {
+                                               r->set_presentation_order (order + added);
+                                               DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("group order not set, set to %1 + %2 = %3\n", order, added, order + added));
+                                       }
+                               } else {
+                                       DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("group order already set to %1\n", r->presentation_info().order()));
+                               }
+                       }
+
+#if !defined(__APPLE__) && !defined(__FreeBSD__)
+                       /* clang complains: 'operator<<' should be declared prior to the call site or in an associated namespace of one of its
+                        * arguments std::ostream& operator<<(std::ostream& o, ARDOUR::PresentationInfo const& rid)"
                         */
+                       DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("added route %1, group order %2 type %3 (summary: %4)\n",
+                                                                      r->name(),
+                                                                      r->presentation_info().order(),
+                                                                      enum_2_string (r->presentation_info().flags()),
+                                                                      r->presentation_info()));
+#endif
 
-               if (!r->has_order_key ()) {
-                       if (r->is_auditioner()) {
-                               /* use an arbitrarily high value */
-                               r->set_order_key (UINT_MAX);
-                       } else {
-                               DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("while adding, set %1 to order key %2\n", r->name(), order));
-                               r->set_order_key (order);
-                               order++;
+
+                       if (input_auto_connect || output_auto_connect) {
+                               auto_connect_route (r, input_auto_connect, ChanCount (), ChanCount (), existing_inputs, existing_outputs);
+                               existing_inputs += r->n_inputs();
+                               existing_outputs += r->n_outputs();
                        }
-               }
 
-               ARDOUR::GUIIdle ();
+                       ARDOUR::GUIIdle ();
+               }
        }
 
        if (_monitor_out && IO::connecting_legal) {
@@ -3472,6 +3602,8 @@ Session::add_routes_inner (RouteList& new_routes, bool input_auto_connect, bool
                        }
                }
        }
+
+       reassign_track_numbers ();
 }
 
 void
@@ -3575,7 +3707,10 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
                                continue;
                        }
 
-                       (*iter)->solo_control()->set_value (0.0, Controllable::NoGroup);
+                       /* speed up session deletion, don't do the solo dance */
+                       if (0 == (_state_of_the_state & Deletion)) {
+                               (*iter)->solo_control()->set_value (0.0, Controllable::NoGroup);
+                       }
 
                        rs->remove (*iter);
 
@@ -3612,7 +3747,7 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
                        /* if the monitoring section had a pointer to this route, remove it */
                        if (_monitor_out && !(*iter)->is_master() && !(*iter)->is_monitor()) {
                                Glib::Threads::Mutex::Lock lm (AudioEngine::instance()->process_lock ());
-                               PBD::Unwinder<bool> uw (ignore_route_processor_changes, true);
+                               ProcessorChangeBlocker pcb (this, false);
                                (*iter)->remove_aux_or_listen (_monitor_out);
                        }
 
@@ -3629,7 +3764,6 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
        } // end of RCU Writer scope
 
        update_route_solo_state ();
-       RouteAddedOrRemoved (false); /* EMIT SIGNAL */
        update_latency_compensation ();
        set_dirty();
 
@@ -3659,6 +3793,7 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
         */
 
        for (RouteList::iterator iter = routes_to_remove->begin(); iter != routes_to_remove->end(); ++iter) {
+               cerr << "Drop references to " << (*iter)->name() << endl;
                (*iter)->drop_references ();
        }
 
@@ -3666,7 +3801,10 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
                return;
        }
 
-       Route::RemoteControlIDChange(); /* EMIT SIGNAL */
+       PropertyChange so;
+       so.add (Properties::selected);
+       so.add (Properties::order);
+       PresentationInfo::Change (PropertyChange (so));
 
        /* save the new state of the world */
 
@@ -3674,7 +3812,6 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
                save_history (_current_snapshot_name);
        }
 
-       reassign_track_numbers();
        update_route_record_state ();
 }
 
@@ -3701,7 +3838,9 @@ Session::route_listen_changed (Controllable::GroupControlDisposition group_overr
                return;
        }
 
-       if (route->listening_via_monitor ()) {
+       assert (Config->get_solo_control_is_listen_control());
+
+       if (route->solo_control()->soloed_by_self_or_masters()) {
 
                if (Config->get_exclusive_solo()) {
 
@@ -3739,8 +3878,6 @@ Session::route_listen_changed (Controllable::GroupControlDisposition group_overr
 
                _listen_cnt--;
        }
-
-       update_route_solo_state ();
 }
 
 void
@@ -3774,7 +3911,7 @@ Session::route_solo_isolated_changed (boost::weak_ptr<Route> wpr)
 void
 Session::route_solo_changed (bool self_solo_changed, Controllable::GroupControlDisposition group_override,  boost::weak_ptr<Route> wpr)
 {
-       DEBUG_TRACE (DEBUG::Solo, string_compose ("route solo change, self = %1\n", self_solo_changed));
+       DEBUG_TRACE (DEBUG::Solo, string_compose ("route solo change, self = %1, update\n", self_solo_changed));
 
        boost::shared_ptr<Route> route (wpr.lock());
 
@@ -3790,21 +3927,13 @@ Session::route_solo_changed (bool self_solo_changed, Controllable::GroupControlD
        DEBUG_TRACE (DEBUG::Solo, string_compose ("%1: self %2 masters %3 transition %4\n", route->name(), route->self_soloed(), route->solo_control()->get_masters_value(), route->solo_control()->transitioned_into_solo()));
 
        if (route->solo_control()->transitioned_into_solo() == 0) {
-               /* route solo changed by upstream/downstream; not interesting
+               /* route solo changed by upstream/downstream or clear all solo state; not interesting
                   to Session.
                */
                DEBUG_TRACE (DEBUG::Solo, string_compose ("%1 not self-soloed nor soloed by master (%2), ignoring\n", route->name(), route->solo_control()->get_masters_value()));
                return;
        }
 
-       if (route->solo_control()->transitioned_into_solo() == 0) {
-               /* reason for being soloed changed (e.g. master went away, we
-                * took over the master state), but actual status did
-                * not. nothing to do.
-                */
-               DEBUG_TRACE (DEBUG::Solo, string_compose ("%1: solo change was change in reason, not status\n", route->name()));
-       }
-
        boost::shared_ptr<RouteList> r = routes.reader ();
        int32_t delta = route->solo_control()->transitioned_into_solo ();
 
@@ -3827,6 +3956,8 @@ Session::route_solo_changed (bool self_solo_changed, Controllable::GroupControlD
        RouteGroup* rg = route->route_group ();
        const bool group_already_accounted_for = (group_override == Controllable::ForGroup);
 
+       DEBUG_TRACE (DEBUG::Solo, string_compose ("propagate to session, group accounted for ? %1\n", group_already_accounted_for));
+
        if (delta == 1 && Config->get_exclusive_solo()) {
 
                /* new solo: disable all other solos, but not the group if its solo-enabled */
@@ -3873,6 +4004,8 @@ Session::route_solo_changed (bool self_solo_changed, Controllable::GroupControlD
 
                if ((*i)->solo_isolate_control()->solo_isolated() || !(*i)->can_solo()) {
                        /* route does not get solo propagated to it */
+                       DEBUG_TRACE (DEBUG::Solo, string_compose ("%1 excluded from solo because iso = %2 can_solo = %3\n", (*i)->name(), (*i)->solo_isolate_control()->solo_isolated(),
+                                                                 (*i)->can_solo()));
                        continue;
                }
 
@@ -3938,8 +4071,6 @@ Session::route_solo_changed (bool self_solo_changed, Controllable::GroupControlD
 
        DEBUG_TRACE (DEBUG::Solo, "propagation complete\n");
 
-       update_route_solo_state (r);
-
        /* now notify that the mute state of the routes not involved in the signal
           pathway of the just-solo-changed route may have altered.
        */
@@ -3947,11 +4078,10 @@ Session::route_solo_changed (bool self_solo_changed, Controllable::GroupControlD
        for (RouteList::iterator i = uninvolved.begin(); i != uninvolved.end(); ++i) {
                DEBUG_TRACE (DEBUG::Solo, string_compose ("mute change for %1, which neither feeds or is fed by %2\n", (*i)->name(), route->name()));
                (*i)->act_on_mute ();
-               (*i)->mute_control()->Changed (false, Controllable::NoGroup);
+               /* Session will emit SoloChanged() after all solo changes are
+                * complete, which should be used by UIs to update mute status
+                */
        }
-
-       SoloChanged (); /* EMIT SIGNAL */
-       set_dirty();
 }
 
 void
@@ -3971,13 +4101,13 @@ Session::update_route_solo_state (boost::shared_ptr<RouteList> r)
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
                if ((*i)->can_solo()) {
                        if (Config->get_solo_control_is_listen_control()) {
-                               if ((*i)->self_soloed() || (*i)->solo_control()->get_masters_value()) {
+                               if ((*i)->solo_control()->soloed_by_self_or_masters()) {
                                        listeners++;
                                        something_listening = true;
                                }
                        } else {
                                (*i)->set_listen (false);
-                               if ((*i)->can_solo() && ((*i)->self_soloed() || (*i)->solo_control()->get_masters_value())) {
+                               if ((*i)->can_solo() && (*i)->solo_control()->soloed_by_self_or_masters()) {
                                        something_soloed = true;
                                }
                        }
@@ -4007,6 +4137,20 @@ Session::update_route_solo_state (boost::shared_ptr<RouteList> r)
 
        DEBUG_TRACE (DEBUG::Solo, string_compose ("solo state updated by session, soloed? %1 listeners %2 isolated %3\n",
                                                  something_soloed, listeners, isolated));
+
+
+       SoloChanged (); /* EMIT SIGNAL */
+       set_dirty();
+}
+
+void
+Session::get_stripables (StripableList& sl) const
+{
+       boost::shared_ptr<RouteList> r = routes.reader ();
+       sl.insert (sl.end(), r->begin(), r->end());
+
+       VCAList v = _vca_manager->vcas ();
+       sl.insert (sl.end(), v.begin(), v.end());
 }
 
 boost::shared_ptr<RouteList>
@@ -4024,13 +4168,13 @@ Session::get_routes_with_internal_returns() const
 }
 
 bool
-Session::io_name_is_legal (const std::string& name)
+Session::io_name_is_legal (const std::string& name) const
 {
        boost::shared_ptr<RouteList> r = routes.reader ();
 
-       for (vector<string>::const_iterator reserved = reserved_io_names.begin(); reserved != reserved_io_names.end(); ++reserved) {
-               if (name == *reserved) {
-                       if (!route_by_name (*reserved)) {
+       for (map<string,bool>::const_iterator reserved = reserved_io_names.begin(); reserved != reserved_io_names.end(); ++reserved) {
+               if (name == reserved->first) {
+                       if (!route_by_name (reserved->first)) {
                                /* first instance of a reserved name is allowed */
                                return true;
                        }
@@ -4133,7 +4277,7 @@ Session::routes_using_input_from (const string& str, RouteList& rl)
 }
 
 boost::shared_ptr<Route>
-Session::route_by_name (string name)
+Session::route_by_name (string name) const
 {
        boost::shared_ptr<RouteList> r = routes.reader ();
 
@@ -4147,7 +4291,7 @@ Session::route_by_name (string name)
 }
 
 boost::shared_ptr<Route>
-Session::route_by_id (PBD::ID id)
+Session::route_by_id (PBD::ID id) const
 {
        boost::shared_ptr<RouteList> r = routes.reader ();
 
@@ -4176,7 +4320,7 @@ Session::processor_by_id (PBD::ID id) const
 }
 
 boost::shared_ptr<Track>
-Session::track_by_diskstream_id (PBD::ID id)
+Session::track_by_diskstream_id (PBD::ID id) const
 {
        boost::shared_ptr<RouteList> r = routes.reader ();
 
@@ -4191,55 +4335,92 @@ Session::track_by_diskstream_id (PBD::ID id)
 }
 
 boost::shared_ptr<Route>
-Session::route_by_remote_id (uint32_t id)
+Session::get_remote_nth_route (PresentationInfo::order_t n) const
 {
-       boost::shared_ptr<RouteList> r = routes.reader ();
-
-       for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
-               if ((*i)->remote_control_id() == id) {
-                       return *i;
-               }
-       }
-
-       return boost::shared_ptr<Route> ((Route*) 0);
+       return boost::dynamic_pointer_cast<Route> (get_remote_nth_stripable (n, PresentationInfo::Route));
 }
 
-
 boost::shared_ptr<Stripable>
-Session::stripable_by_remote_id (uint32_t id)
+Session::get_remote_nth_stripable (PresentationInfo::order_t n, PresentationInfo::Flag flags) const
 {
-       boost::shared_ptr<RouteList> r = routes.reader ();
+       StripableList sl;
+       PresentationInfo::order_t match_cnt = 0;
 
-       for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
-               if ((*i)->remote_control_id() == id) {
-                       return *i;
+       get_stripables (sl);
+       sl.sort (Stripable::PresentationOrderSorter());
+
+       for (StripableList::const_iterator s = sl.begin(); s != sl.end(); ++s) {
+
+               if ((*s)->presentation_info().hidden()) {
+                       /* if the caller didn't explicitly ask for hidden
+                          stripables, ignore hidden ones. This matches
+                          the semantics of the pre-PresentationOrder
+                          "get by RID" logic of Ardour 4.x and earlier.
+
+                          XXX at some point we should likely reverse
+                          the logic of the flags, because asking for "the
+                          hidden stripables" is not going to be common,
+                          whereas asking for visible ones is normal.
+                       */
+
+                       if (! (flags & PresentationInfo::Hidden)) {
+                               continue;
+                       }
+               }
+
+               if ((*s)->presentation_info().flag_match (flags)) {
+                       if (match_cnt++ == n) {
+                               return *s;
+                       }
                }
        }
 
-       return boost::shared_ptr<Route> ((Route*) 0);
+       /* there is no nth stripable that matches the given flags */
+       return boost::shared_ptr<Stripable>();
 }
 
+struct PresentationOrderSorter {
+       bool operator() (boost::shared_ptr<Stripable> a, boost::shared_ptr<Stripable> b) {
+               if (a->presentation_info().special() && !b->presentation_info().special()) {
+                       /* a is not ordered, b is; b comes before a */
+                       return false;
+               } else if (!b->presentation_info().order_set() && a->presentation_info().order_set()) {
+                       /* b is not ordered, a is; a comes before b */
+                       return true;
+               } else {
+                       return a->presentation_info().order() < b->presentation_info().order();
+               }
+       }
+};
 
 boost::shared_ptr<Route>
-Session::route_by_selected_count (uint32_t id)
+Session::route_by_selected_count (uint32_t id) const
 {
-       boost::shared_ptr<RouteList> r = routes.reader ();
+       RouteList r (*(routes.reader ()));
+       PresentationOrderSorter sorter;
+       r.sort (sorter);
 
-       for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
-               /* NOT IMPLEMENTED */
+       RouteList::iterator i;
+
+       for (i = r.begin(); i != r.end(); ++i) {
+               if ((*i)->presentation_info().selected()) {
+                       if (id == 0) {
+                               return *i;
+                       }
+                       --id;
+               }
        }
 
-       return boost::shared_ptr<Route> ((Route*) 0);
+       return boost::shared_ptr<Route> ();
 }
 
-
 void
 Session::reassign_track_numbers ()
 {
        int64_t tn = 0;
        int64_t bn = 0;
        RouteList r (*(routes.reader ()));
-       SignalOrderRouteSorter sorter;
+       PresentationOrderSorter sorter;
        r.sort (sorter);
 
        StateProtector sp (this);
@@ -4266,6 +4447,16 @@ Session::reassign_track_numbers ()
                // trigger GUI re-layout
                config.ParameterChanged("track-name-number");
        }
+
+#ifndef NDEBUG
+       if (DEBUG_ENABLED(DEBUG::OrderKeys)) {
+               boost::shared_ptr<RouteList> rl = routes.reader ();
+               for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
+                       DEBUG_TRACE (DEBUG::OrderKeys, string_compose ("%1 numbered %2\n", (*i)->name(), (*i)->track_number()));
+               }
+       }
+#endif /* NDEBUG */
+
 }
 
 void
@@ -4331,12 +4522,18 @@ Session::maybe_update_session_range (framepos_t a, framepos_t b)
                        _session_range_location->set_start (a);
                }
 
-               if (b > _session_range_location->end()) {
+               if (_session_range_end_is_free && (b > _session_range_location->end())) {
                        _session_range_location->set_end (b);
                }
        }
 }
 
+void
+Session::set_end_is_free (bool yn)
+{
+       _session_range_end_is_free = yn;
+}
+
 void
 Session::playlist_ranges_moved (list<Evoral::RangeMove<framepos_t> > const & ranges)
 {
@@ -5074,6 +5271,9 @@ Session::register_lua_function (
                tbl_arg[(*i)->name] = (*i)->value;
        }
        (*_lua_add)(name, bytecode, tbl_arg); // throws luabridge::LuaException
+       lm.release();
+
+       LuaScriptsChanged (); /* EMIT SIGNAL */
        set_dirty();
 }
 
@@ -5083,6 +5283,9 @@ Session::unregister_lua_function (const std::string& name)
        Glib::Threads::Mutex::Lock lm (lua_lock);
        (*_lua_del)(name); // throws luabridge::LuaException
        lua.collect_garbage ();
+       lm.release();
+
+       LuaScriptsChanged (); /* EMIT SIGNAL */
        set_dirty();
 }
 
@@ -5115,6 +5318,7 @@ Session::try_run_lua (pframes_t nframes)
        Glib::Threads::Mutex::Lock tm (lua_lock, Glib::Threads::TRY_LOCK);
        if (tm.locked ()) {
                try { (*_lua_run)(nframes); } catch (luabridge::LuaException const& e) { }
+               lua.collect_garbage_step ();
        }
 }
 
@@ -5124,6 +5328,7 @@ Session::setup_lua ()
 #ifndef NDEBUG
        lua.Print.connect (&_lua_print);
 #endif
+       lua.tweak_rt_gc ();
        lua.do_command (
                        "function ArdourSession ()"
                        "  local self = { scripts = {}, instances = {} }"
@@ -5141,7 +5346,7 @@ Session::setup_lua ()
                        "   assert(self.scripts[n] == nil, 'Callback \"'.. n ..'\" already exists.')"
                        "   self.scripts[n] = { ['f'] = f, ['a'] = a }"
                        "   local env = _ENV;  env.f = nil env.io = nil env.os = nil env.loadfile = nil env.require = nil env.dofile = nil env.package = nil env.debug = nil"
-                       "   local env = { print = print, tostring = tostring, assert = assert, ipairs = ipairs, error = error, select = select, string = string, type = type, tonumber = tonumber, collectgarbage = collectgarbage, pairs = pairs, math = math, table = table, pcall = pcall, Session = Session, PBD = PBD, Timecode = Timecode, Evoral = Evoral, C = C, ARDOUR = ARDOUR }"
+                       "   local env = { print = print, tostring = tostring, assert = assert, ipairs = ipairs, error = error, select = select, string = string, type = type, tonumber = tonumber, collectgarbage = collectgarbage, pairs = pairs, math = math, table = table, pcall = pcall, bit32=bit32, Session = Session, PBD = PBD, Timecode = Timecode, Evoral = Evoral, C = C, ARDOUR = ARDOUR }"
                        "   self.instances[n] = load (string.dump(f, true), nil, nil, env)(a)"
                        "   Session:scripts_changed()" // call back
                        "  end"
@@ -5315,7 +5520,7 @@ Session::RoutePublicOrderSorter::operator() (boost::shared_ptr<Route> a, boost::
        if (b->is_monitor()) {
                return false;
        }
-       return a->order_key () < b->order_key ();
+       return a->presentation_info().order() < b->presentation_info().order();
 }
 
 bool
@@ -5470,21 +5675,11 @@ Session::tempo_map_changed (const PropertyChange&)
        set_dirty ();
 }
 
-void
-Session::gui_tempo_map_changed ()
-{
-       clear_clicks ();
-
-       playlists->update_after_tempo_map_change ();
-
-       _locations->apply (*this, &Session::update_locations_after_tempo_map_change);
-}
-
 void
 Session::update_locations_after_tempo_map_change (const Locations::LocationList& loc)
 {
        for (Locations::LocationList::const_iterator i = loc.begin(); i != loc.end(); ++i) {
-               (*i)->recompute_frames_from_bbt ();
+               (*i)->recompute_frames_from_beat ();
        }
 }
 
@@ -6114,8 +6309,8 @@ Session::update_route_record_state ()
 void
 Session::listen_position_changed ()
 {
+       ProcessorChangeBlocker pcb (this);
        boost::shared_ptr<RouteList> r = routes.reader ();
-
        for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
                (*i)->listen_position_changed ();
        }
@@ -6125,14 +6320,18 @@ void
 Session::solo_control_mode_changed ()
 {
        if (soloing() || listening()) {
-               /* We can't use ::clear_all_solo_state() here because during
-                  session loading at program startup, that will queue a call
-                  to rt_clear_all_solo_state() that will not execute until
-                  AFTER solo states have been established (thus throwing away
-                  the session's saved solo state). So just explicitly turn
-                  them all off.
-               */
-               set_controls (route_list_to_control_list (get_routes(), &Route::solo_control), 0.0, Controllable::NoGroup);
+               if (loading()) {
+                       /* We can't use ::clear_all_solo_state() here because during
+                          session loading at program startup, that will queue a call
+                          to rt_clear_all_solo_state() that will not execute until
+                          AFTER solo states have been established (thus throwing away
+                          the session's saved solo state). So just explicitly turn
+                          them all off.
+                       */
+                       set_controls (route_list_to_control_list (get_routes(), &Stripable::solo_control), 0.0, Controllable::NoGroup);
+               } else {
+                       clear_all_solo_state (get_routes());
+               }
        }
 }
 
@@ -6156,6 +6355,10 @@ Session::route_removed_from_route_group (RouteGroup* rg, boost::weak_ptr<Route>
 {
        update_route_record_state ();
        RouteRemovedFromRouteGroup (rg, r); /* EMIT SIGNAL */
+
+       if (!rg->has_control_master () && !rg->has_subgroup () && rg->empty()) {
+               remove_route_group (*rg);
+       }
 }
 
 boost::shared_ptr<RouteList>
@@ -6210,12 +6413,12 @@ Session::goto_end ()
 }
 
 void
-Session::goto_start ()
+Session::goto_start (bool and_roll)
 {
        if (_session_range_location) {
-               request_locate (_session_range_location->start(), false);
+               request_locate (_session_range_location->start(), and_roll);
        } else {
-               request_locate (0, false);
+               request_locate (0, and_roll);
        }
 }
 
@@ -6234,7 +6437,7 @@ Session::current_end_frame () const
 void
 Session::set_session_range_location (framepos_t start, framepos_t end)
 {
-       _session_range_location = new Location (*this, start, end, _("session"), Location::IsSessionRange);
+       _session_range_location = new Location (*this, start, end, _("session"), Location::IsSessionRange, 0);
        _locations->add (_session_range_location);
 }
 
@@ -6281,6 +6484,7 @@ Session::start_time_changed (framepos_t old)
        if (l && l->start() == old) {
                l->set_start (s->start(), true);
        }
+       set_dirty ();
 }
 
 void
@@ -6300,6 +6504,7 @@ Session::end_time_changed (framepos_t old)
        if (l && l->end() == old) {
                l->set_end (s->end(), true);
        }
+       set_dirty ();
 }
 
 std::vector<std::string>
@@ -6655,75 +6860,24 @@ Session::session_name_is_legal (const string& path)
        return 0;
 }
 
-uint32_t
-Session::next_control_id () const
-{
-       int subtract = 0;
-
-       /* the monitor bus remote ID is in a different
-        * "namespace" than regular routes. its existence doesn't
-        * affect normal (low) numbered routes.
-        */
-
-       if (_monitor_out) {
-               subtract++;
-       }
-
-       /* the same about masterbus in Waves Tracks */
-
-       if (Profile->get_trx() && _master_out) {
-               subtract++;
-       }
-
-       return nroutes() - subtract;
-}
-
 void
-Session::notify_remote_id_change ()
+Session::notify_presentation_info_change ()
 {
        if (deletion_in_progress()) {
                return;
        }
 
-       switch (Config->get_remote_model()) {
-       case MixerOrdered:
-               Route::RemoteControlIDChange (); /* EMIT SIGNAL */
-               break;
-       default:
-               break;
-       }
+       reassign_track_numbers();
 
 #ifdef USE_TRACKS_CODE_FEATURES
-               /* Waves Tracks: for Waves Tracks session it's required to reconnect their IOs
-                * if track order has been changed by user
-                */
-               reconnect_existing_routes(true, true);
+       /* Waves Tracks: for Waves Tracks session it's required to reconnect their IOs
+        * if track order has been changed by user
+        */
+       reconnect_existing_routes(true, true);
 #endif
 
 }
 
-void
-Session::sync_order_keys ()
-{
-       if (deletion_in_progress()) {
-               return;
-       }
-
-       /* tell everyone that something has happened to the sort keys
-          and let them sync up with the change(s)
-          this will give objects that manage the sort order keys the
-          opportunity to keep them in sync if they wish to.
-       */
-
-       DEBUG_TRACE (DEBUG::OrderKeys, "Sync Order Keys.\n");
-
-       reassign_track_numbers();
-
-       Route::SyncOrderKeys (); /* EMIT SIGNAL */
-
-       DEBUG_TRACE (DEBUG::OrderKeys, "\tsync done\n");
-}
-
 bool
 Session::operation_in_progress (GQuark op) const
 {
@@ -6825,12 +6979,25 @@ Session::auto_connect_route (boost::shared_ptr<Route> route, bool connect_inputs
                                input_start, output_start,
                                input_offset, output_offset));
 
+       auto_connect_thread_wakeup ();
+}
+
+void
+Session::auto_connect_thread_wakeup ()
+{
        if (pthread_mutex_trylock (&_auto_connect_mutex) == 0) {
                pthread_cond_signal (&_auto_connect_cond);
                pthread_mutex_unlock (&_auto_connect_mutex);
        }
 }
 
+void
+Session::queue_latency_recompute ()
+{
+       g_atomic_int_inc (&_latency_recompute_pending);
+       auto_connect_thread_wakeup ();
+}
+
 void
 Session::auto_connect (const AutoConnectRequest& ar)
 {
@@ -6867,8 +7034,12 @@ Session::auto_connect (const AutoConnectRequest& ar)
                vector<string> physinputs;
                vector<string> physoutputs;
 
-               _engine.get_physical_outputs (*t, physoutputs);
-               _engine.get_physical_inputs (*t, physinputs);
+
+               /* for connecting track inputs we only want MIDI ports marked
+                * for "music".
+                */
+
+               get_physical_ports (physinputs, physoutputs, *t, MidiPortMusic);
 
                if (!physinputs.empty() && ar.connect_inputs) {
                        uint32_t nphysical_in = physinputs.size();
@@ -6922,7 +7093,7 @@ Session::auto_connect (const AutoConnectRequest& ar)
 void
 Session::auto_connect_thread_start ()
 {
-       if (_ac_thread_active) {
+       if (g_atomic_int_get (&_ac_thread_active)) {
                return;
        }
 
@@ -6930,19 +7101,18 @@ Session::auto_connect_thread_start ()
                _auto_connect_queue.pop ();
        }
 
-       _ac_thread_active = true;
+       g_atomic_int_set (&_ac_thread_active, 1);
        if (pthread_create (&_auto_connect_thread, NULL, auto_connect_thread, this)) {
-               _ac_thread_active = false;
+               g_atomic_int_set (&_ac_thread_active, 0);
        }
 }
 
 void
 Session::auto_connect_thread_terminate ()
 {
-       if (!_ac_thread_active) {
+       if (!g_atomic_int_get (&_ac_thread_active)) {
                return;
        }
-       _ac_thread_active = false;
 
        {
                Glib::Threads::Mutex::Lock lx (_auto_connect_queue_lock);
@@ -6951,10 +7121,14 @@ Session::auto_connect_thread_terminate ()
                }
        }
 
-       if (pthread_mutex_lock (&_auto_connect_mutex) == 0) {
-               pthread_cond_signal (&_auto_connect_cond);
-               pthread_mutex_unlock (&_auto_connect_mutex);
-       }
+       /* cannot use auto_connect_thread_wakeup() because that is allowed to
+        * fail to wakeup the thread.
+        */
+
+       pthread_mutex_lock (&_auto_connect_mutex);
+       g_atomic_int_set (&_ac_thread_active, 0);
+       pthread_cond_signal (&_auto_connect_cond);
+       pthread_mutex_unlock (&_auto_connect_mutex);
 
        void *status;
        pthread_join (_auto_connect_thread, &status);
@@ -6976,7 +7150,7 @@ Session::auto_connect_thread_run ()
        SessionEvent::create_per_thread_pool (X_("autoconnect"), 1024);
        PBD::notify_event_loops_about_thread_creation (pthread_self(), X_("autoconnect"), 1024);
        pthread_mutex_lock (&_auto_connect_mutex);
-       while (_ac_thread_active) {
+       while (g_atomic_int_get (&_ac_thread_active)) {
 
                if (!_auto_connect_queue.empty ()) {
                        // Why would we need the process lock ??
@@ -6996,7 +7170,39 @@ Session::auto_connect_thread_run ()
                        }
                }
 
+               if (!actively_recording ()) { // might not be needed,
+                       /* this is only used for updating plugin latencies, the
+                        * graph does not change. so it's safe in general.
+                        * BUT..
+                        * .. update_latency_compensation () entails set_capture_offset()
+                        * which calls Diskstream::set_capture_offset () which
+                        * modifies the capture offset... which can be a proplem
+                        * in "prepare_to_stop"
+                        */
+                       while (g_atomic_int_and (&_latency_recompute_pending, 0)) {
+                               update_latency_compensation ();
+                       }
+               }
+
+               {
+                       // this may call ARDOUR::Port::drop ... jack_port_unregister ()
+                       // jack1 cannot cope with removing ports while processing
+                       Glib::Threads::Mutex::Lock lm (AudioEngine::instance()->process_lock ());
+                       AudioEngine::instance()->clear_pending_port_deletions ();
+               }
+
                pthread_cond_wait (&_auto_connect_cond, &_auto_connect_mutex);
        }
        pthread_mutex_unlock (&_auto_connect_mutex);
 }
+
+void
+Session::cancel_all_solo ()
+{
+       StripableList sl;
+
+       get_stripables (sl);
+
+       set_controls (stripable_list_to_control_list (sl, &Stripable::solo_control), 0.0, Controllable::NoGroup);
+       clear_all_solo_state (routes.reader());
+}