libs/ardour/session_process.cc

   1 /*
   2     Copyright (C) 1999-2002 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <cmath>
  21 #include <cerrno>
  22 #include <algorithm>
  23 #include <unistd.h>
  24
  25 #include "pbd/error.h"
  26 #include "pbd/enumwriter.h"
  27
  28 #include <glibmm/thread.h>
  29
  30 #include "ardour/ardour.h"
  31 #include "ardour/audioengine.h"
  32 #include "ardour/auditioner.h"
  33 #include "ardour/butler.h"
  34 #include "ardour/debug.h"
  35 #include "ardour/process_thread.h"
  36 #include "ardour/session.h"
  37 #include "ardour/slave.h"
  38 #include "ardour/timestamps.h"
  39 #include "ardour/graph.h"
  40 #include "ardour/audio_port.h"
  41
  42 #include "midi++/manager.h"
  43 #include "midi++/mmc.h"
  44
  45 #include "i18n.h"
  46
  47 using namespace ARDOUR;
  48 using namespace PBD;
  49 using namespace std;
  50
  51 /** Called by the audio engine when there is work to be done with JACK.
  52  * @param nframes Number of frames to process.
  53  */
  54
  55 void
  56 Session::process (pframes_t nframes)
  57 {
  58         MIDI::Manager::instance()->cycle_start(nframes);
  59
  60         _silent = false;
  61
  62         if (processing_blocked()) {
  63                 _silent = true;
  64                 return;
  65         }
  66
  67         if (non_realtime_work_pending()) {
  68                 if (!_butler->transport_work_requested ()) {
  69                         post_transport ();
  70                 }
  71         }
  72
  73         _engine.main_thread()->get_buffers ();
  74
  75         (this->*process_function) (nframes);
  76
  77         _engine.main_thread()->drop_buffers ();
  78
  79         // the ticker is for sending time information like MidiClock
  80         framepos_t transport_frames = transport_frame();
  81         Timecode::BBT_Time transport_bbt;
  82         bbt_time(transport_frames, transport_bbt);
  83         Timecode::Time transport_timecode;
  84         timecode_time(transport_frames, transport_timecode);
  85         tick (transport_frames, transport_bbt, transport_timecode); /* EMIT SIGNAL */
  86
  87         SendFeedback (); /* EMIT SIGNAL */
  88
  89         MIDI::Manager::instance()->cycle_end();
  90 }
  91
  92 int
  93 Session::fail_roll (pframes_t nframes)
  94 {
  95         return no_roll (nframes);
  96 }
  97
  98 int
  99 Session::no_roll (pframes_t nframes)
 100 {
 101         framepos_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 102         int ret = 0;
 103         bool declick = get_transport_declick_required();
 104         boost::shared_ptr<RouteList> r = routes.reader ();
 105
 106         if (_click_io) {
 107                 _click_io->silence (nframes);
 108         }
 109
 110         if (route_graph->threads_in_use() > 0) {
 111                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/no-roll\n");
 112                 route_graph->routes_no_roll( nframes, _transport_frame, end_frame, non_realtime_work_pending(), actively_recording(), declick);
 113         } else {
 114                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 115
 116                         if ((*i)->is_hidden()) {
 117                                 continue;
 118                         }
 119
 120                         (*i)->set_pending_declick (declick);
 121
 122                         if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending(),
 123                                            actively_recording(), declick)) {
 124                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 125                                 ret = -1;
 126                                 break;
 127                         }
 128                 }
 129         }
 130
 131         return ret;
 132 }
 133
 134 int
 135 Session::process_routes (pframes_t nframes, bool& need_butler)
 136 {
 137         bool record_active;
 138         int  declick = get_transport_declick_required();
 139         bool rec_monitors = get_rec_monitors_input();
 140         boost::shared_ptr<RouteList> r = routes.reader ();
 141
 142         if (transport_sub_state & StopPendingCapture) {
 143                 /* force a declick out */
 144                 declick = -1;
 145         }
 146
 147         record_active = actively_recording(); // || (get_record_enabled() && get_punch_in());
 148
 149         const framepos_t start_frame = _transport_frame;
 150         const framepos_t end_frame = _transport_frame + floor (nframes * _transport_speed);
 151
 152         /* XXX this is hack to force use of the graph even if we are only
 153            using 1 thread. its needed because otherwise when we remove
 154            tracks, the graph never gets updated.
 155         */
 156         if (1 || route_graph->threads_in_use() > 0) {
 157                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/process-routes\n");
 158                 route_graph->process_routes( nframes, start_frame, end_frame, declick, record_active, rec_monitors, need_butler);
 159         } else {
 160
 161                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 162
 163                         int ret;
 164
 165                         if ((*i)->is_hidden()) {
 166                                 continue;
 167                         }
 168
 169                         (*i)->set_pending_declick (declick);
 170
 171                         if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, record_active, rec_monitors, need_butler)) < 0) {
 172                                 stop_transport ();
 173                                 return -1;
 174                         }
 175                 }
 176         }
 177
 178         return 0;
 179 }
 180
 181 int
 182 Session::silent_process_routes (pframes_t nframes, bool& need_butler)
 183 {
 184         bool record_active = actively_recording();
 185         int  declick = get_transport_declick_required();
 186         bool rec_monitors = get_rec_monitors_input();
 187         boost::shared_ptr<RouteList> r = routes.reader ();
 188
 189         if (transport_sub_state & StopPendingCapture) {
 190                 /* force a declick out */
 191                 declick = -1;
 192         }
 193
 194         const framepos_t start_frame = _transport_frame;
 195         const framepos_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 196
 197         /* XXX this is hack to force use of the graph even if we are only
 198            using 1 thread. its needed because otherwise when we remove
 199            tracks, the graph never gets updated.
 200         */
 201         if (1 || route_graph->threads_in_use() > 0) {
 202                 route_graph->silent_process_routes( nframes, start_frame, end_frame, record_active, rec_monitors, need_butler);
 203         } else {
 204                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 205
 206                         int ret;
 207
 208                         if ((*i)->is_hidden()) {
 209                                 continue;
 210                         }
 211
 212                         if ((ret = (*i)->silent_roll (nframes, start_frame, end_frame, record_active, rec_monitors, need_butler)) < 0) {
 213                                 stop_transport ();
 214                                 return -1;
 215                         }
 216                 }
 217         }
 218
 219         return 0;
 220 }
 221
 222 void
 223 Session::get_track_statistics ()
 224 {
 225         float pworst = 1.0f;
 226         float cworst = 1.0f;
 227
 228         boost::shared_ptr<RouteList> rl = routes.reader();
 229         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 230
 231                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 232
 233                 if (!tr || tr->hidden()) {
 234                         continue;
 235                 }
 236
 237                 pworst = min (pworst, tr->playback_buffer_load());
 238                 cworst = min (cworst, tr->capture_buffer_load());
 239         }
 240
 241         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 242         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 243
 244         if (actively_recording()) {
 245                 set_dirty();
 246         }
 247 }
 248
 249 /** Process callback used when the auditioner is not active */
 250 void
 251 Session::process_with_events (pframes_t nframes)
 252 {
 253         SessionEvent*  ev;
 254         pframes_t      this_nframes;
 255         framepos_t     end_frame;
 256         bool           session_needs_butler = false;
 257         framepos_t     stop_limit;
 258         framecnt_t     frames_moved;
 259
 260         /* make sure the auditioner is silent */
 261
 262         if (auditioner) {
 263                 auditioner->silence (nframes);
 264         }
 265
 266         /* handle any pending events */
 267
 268         while (pending_events.read (&ev, 1) == 1) {
 269                 merge_event (ev);
 270         }
 271
 272         /* if we are not in the middle of a state change,
 273            and there are immediate events queued up,
 274            process them.
 275         */
 276
 277         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 278                 SessionEvent *ev = immediate_events.front ();
 279                 immediate_events.pop_front ();
 280                 process_event (ev);
 281         }
 282
 283         /* Decide on what to do with quarter-frame MTC during this cycle */
 284
 285         bool const was_sending_qf_mtc = _send_qf_mtc;
 286         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 287
 288         if (_transport_speed != 0) {
 289                 _send_qf_mtc = (
 290                         Config->get_send_mtc () &&
 291                         _transport_speed >= (1 - tolerance) &&
 292                         _transport_speed <= (1 + tolerance)
 293                         );
 294
 295                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 296                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 297                         _send_timecode_update = true;
 298                 }
 299
 300                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (frame_rate () / 4)) {
 301                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 302                            a quarter of a second since we sent anything at all, so send a full MTC update
 303                            this cycle.
 304                         */
 305                         _send_timecode_update = true;
 306                 }
 307
 308                 _pframes_since_last_mtc += nframes;
 309         }
 310
 311         /* Events caused a transport change (or we re-started sending
 312          * MTC), so send an MTC Full Frame (Timecode) message.  This
 313          * is sent whether rolling or not, to give slaves an idea of
 314          * ardour time on locates (and allow slow slaves to position
 315          * and prepare for rolling)
 316          */
 317         if (_send_timecode_update) {
 318                 send_full_time_code (_transport_frame);
 319         }
 320
 321         if (!process_can_proceed()) {
 322                 _silent = true;
 323                 return;
 324         }
 325
 326         if (events.empty() || next_event == events.end()) {
 327                 process_without_events (nframes);
 328                 return;
 329         }
 330
 331         if (_transport_speed == 1.0) {
 332                 frames_moved = (framecnt_t) nframes;
 333         } else {
 334                 interpolation.set_target_speed (fabs(_target_transport_speed));
 335                 interpolation.set_speed (fabs(_transport_speed));
 336                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 337         }
 338
 339         end_frame = _transport_frame + frames_moved;
 340
 341         {
 342                 SessionEvent* this_event;
 343                 Events::iterator the_next_one;
 344
 345                 if (!process_can_proceed()) {
 346                         _silent = true;
 347                         return;
 348                 }
 349
 350                 if (!_exporting && _slave) {
 351                         if (!follow_slave (nframes)) {
 352                                 return;
 353                         }
 354                 }
 355
 356                 if (_transport_speed == 0) {
 357                         no_roll (nframes);
 358                         return;
 359                 }
 360
 361                 if (!_exporting && !timecode_transmission_suspended()) {
 362                         send_midi_time_code_for_cycle (_transport_frame, end_frame, nframes);
 363                 }
 364
 365                 if (actively_recording()) {
 366                         stop_limit = max_framepos;
 367                 } else {
 368
 369                         if (Config->get_stop_at_session_end()) {
 370                                 stop_limit = current_end_frame();
 371                         } else {
 372                                 stop_limit = max_framepos;
 373                         }
 374                 }
 375
 376                 if (maybe_stop (stop_limit)) {
 377                         no_roll (nframes);
 378                         return;
 379                 }
 380
 381                 this_event = *next_event;
 382                 the_next_one = next_event;
 383                 ++the_next_one;
 384
 385                 /* yes folks, here it is, the actual loop where we really truly
 386                    process some audio
 387                 */
 388
 389                 while (nframes) {
 390
 391                         this_nframes = nframes; /* real (jack) time relative */
 392                         frames_moved = (framecnt_t) floor (_transport_speed * nframes); /* transport relative */
 393
 394                         /* running an event, position transport precisely to its time */
 395                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 396                                 /* this isn't quite right for reverse play */
 397                                 frames_moved = (framecnt_t) (this_event->action_frame - _transport_frame);
 398                                 this_nframes = abs (floor(frames_moved / _transport_speed));
 399                         }
 400
 401                         if (this_nframes) {
 402
 403                                 click (_transport_frame, this_nframes);
 404
 405                                 if (process_routes (this_nframes, session_needs_butler)) {
 406                                         fail_roll (nframes);
 407                                         return;
 408                                 }
 409
 410                                 get_track_statistics ();
 411
 412                                 nframes -= this_nframes;
 413
 414                                 if (frames_moved < 0) {
 415                                         decrement_transport_position (-frames_moved);
 416                                 } else {
 417                                         increment_transport_position (frames_moved);
 418                                 }
 419
 420                                 maybe_stop (stop_limit);
 421                                 check_declick_out ();
 422                         }
 423
 424                         _engine.split_cycle (this_nframes);
 425
 426                         /* now handle this event and all others scheduled for the same time */
 427
 428                         while (this_event && this_event->action_frame == _transport_frame) {
 429                                 process_event (this_event);
 430
 431                                 if (the_next_one == events.end()) {
 432                                         this_event = 0;
 433                                 } else {
 434                                         this_event = *the_next_one;
 435                                         ++the_next_one;
 436                                 }
 437                         }
 438
 439                         /* if an event left our state changing, do the right thing */
 440
 441                         if (nframes && non_realtime_work_pending()) {
 442                                 no_roll (nframes);
 443                                 break;
 444                         }
 445
 446                         /* this is necessary to handle the case of seamless looping */
 447                         end_frame = _transport_frame + floor (nframes * _transport_speed);
 448                 }
 449
 450                 set_next_event ();
 451
 452         } /* implicit release of route lock */
 453
 454         if (session_needs_butler) {
 455                 _butler->summon ();
 456         }
 457 }
 458
 459 void
 460 Session::reset_slave_state ()
 461 {
 462         average_slave_delta = 1800;
 463         delta_accumulator_cnt = 0;
 464         have_first_delta_accumulator = false;
 465         _slave_state = Stopped;
 466 }
 467
 468 bool
 469 Session::transport_locked () const
 470 {
 471         Slave* sl = _slave;
 472
 473         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 474                 return true;
 475         }
 476
 477         return false;
 478 }
 479
 480 bool
 481 Session::follow_slave (pframes_t nframes)
 482 {
 483         double slave_speed;
 484         framepos_t slave_transport_frame;
 485         framecnt_t this_delta;
 486         int dir;
 487
 488         if (!_slave->ok()) {
 489                 stop_transport ();
 490                 config.set_external_sync (false);
 491                 goto noroll;
 492         }
 493
 494         _slave->speed_and_position (slave_speed, slave_transport_frame);
 495
 496         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 497
 498         if (!_slave->locked()) {
 499                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 500                 goto noroll;
 501         }
 502
 503         if (slave_transport_frame > _transport_frame) {
 504                 this_delta = slave_transport_frame - _transport_frame;
 505                 dir = 1;
 506         } else {
 507                 this_delta = _transport_frame - slave_transport_frame;
 508                 dir = -1;
 509         }
 510
 511         if (_slave->starting()) {
 512                 slave_speed = 0.0f;
 513         }
 514
 515         if (_slave->is_always_synced() || config.get_timecode_source_is_synced()) {
 516
 517                 /* if the TC source is synced, then we assume that its
 518                    speed is binary: 0.0 or 1.0
 519                 */
 520
 521                 if (slave_speed != 0.0f) {
 522                         slave_speed = 1.0f;
 523                 }
 524
 525         } else {
 526
 527                 /* if we are chasing and the average delta between us and the
 528                    master gets too big, we want to switch to silent
 529                    motion. so keep track of that here.
 530                 */
 531
 532                 if (_slave_state == Running) {
 533                         calculate_moving_average_of_slave_delta(dir, this_delta);
 534                 }
 535         }
 536
 537         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 538
 539         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 540                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 541
 542
 543         if (_slave_state == Running && !_slave->is_always_synced() && !config.get_timecode_source_is_synced()) {
 544
 545                 if (_transport_speed != 0.0f) {
 546
 547                         /*
 548                            note that average_dir is +1 or -1
 549                         */
 550
 551                         float delta;
 552
 553                         if (average_slave_delta == 0) {
 554                                 delta = this_delta;
 555                                 delta *= dir;
 556                         } else {
 557                                 delta = average_slave_delta;
 558                                 delta *= average_dir;
 559                         }
 560
 561 #ifndef NDEBUG
 562                         if (slave_speed != 0.0) {
 563                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 564                                                                            (int) (dir * this_delta),
 565                                                                            slave_speed,
 566                                                                            _transport_speed,
 567                                                                            _transport_frame,
 568                                                                            slave_transport_frame,
 569                                                                            average_slave_delta));
 570                         }
 571 #endif
 572
 573                         if (_slave->give_slave_full_control_over_transport_speed()) {
 574                                 set_transport_speed (slave_speed, false, false);
 575                                 //std::cout << "set speed = " << slave_speed << "\n";
 576                         } else {
 577                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 578                                 request_transport_speed (adjusted_speed);
 579                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 580                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 581                                                                            slave_speed));
 582                         }
 583
 584 #if 1
 585                         if ((framecnt_t) abs(average_slave_delta) > _slave->resolution()) {
 586                                 cerr << "average slave delta greater than slave resolution (" << _slave->resolution() << "), going to silent motion\n";
 587                                 goto silent_motion;
 588                         }
 589 #endif
 590                 }
 591         }
 592
 593
 594         if (_slave_state == Running && !non_realtime_work_pending()) {
 595                 /* speed is set, we're locked, and good to go */
 596                 return true;
 597         }
 598
 599   silent_motion:
 600         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 601         follow_slave_silently (nframes, slave_speed);
 602
 603   noroll:
 604         /* don't move at all */
 605         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 606         no_roll (nframes);
 607         return false;
 608 }
 609
 610 void
 611 Session::calculate_moving_average_of_slave_delta (int dir, framecnt_t this_delta)
 612 {
 613         if (delta_accumulator_cnt >= delta_accumulator_size) {
 614                 have_first_delta_accumulator = true;
 615                 delta_accumulator_cnt = 0;
 616         }
 617
 618         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 619                 delta_accumulator[delta_accumulator_cnt++] = (framecnt_t) dir *  (framecnt_t) this_delta;
 620         }
 621
 622         if (have_first_delta_accumulator) {
 623                 average_slave_delta = 0L;
 624                 for (int i = 0; i < delta_accumulator_size; ++i) {
 625                         average_slave_delta += delta_accumulator[i];
 626                 }
 627                 average_slave_delta /= (int32_t) delta_accumulator_size;
 628                 if (average_slave_delta < 0L) {
 629                         average_dir = -1;
 630                         average_slave_delta = abs(average_slave_delta);
 631                 } else {
 632                         average_dir = 1;
 633                 }
 634         }
 635 }
 636
 637 void
 638 Session::track_slave_state (float slave_speed, framepos_t slave_transport_frame, framecnt_t this_delta)
 639 {
 640         if (slave_speed != 0.0f) {
 641
 642                 /* slave is running */
 643
 644                 switch (_slave_state) {
 645                 case Stopped:
 646                         if (_slave->requires_seekahead()) {
 647                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 648                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 649                                 /* we can call locate() here because we are in process context */
 650                                 locate (slave_wait_end, false, false);
 651                                 _slave_state = Waiting;
 652
 653                         } else {
 654
 655                                 _slave_state = Running;
 656
 657                                 Location* al = _locations->auto_loop_location();
 658
 659                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 660                                         // cancel looping
 661                                         request_play_loop(false);
 662                                 }
 663
 664                                 if (slave_transport_frame != _transport_frame) {
 665                                         locate (slave_transport_frame, false, false);
 666                                 }
 667                         }
 668                         break;
 669
 670                 case Waiting:
 671                 default:
 672                         break;
 673                 }
 674
 675                 if (_slave_state == Waiting) {
 676
 677                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 678
 679                         if (slave_transport_frame >= slave_wait_end) {
 680
 681                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 682
 683                                 _slave_state = Running;
 684
 685                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 686                                    precisely with the master.
 687                                 */
 688
 689
 690                                 bool ok = true;
 691                                 framecnt_t frame_delta = slave_transport_frame - _transport_frame;
 692
 693                                 boost::shared_ptr<RouteList> rl = routes.reader();
 694                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 695                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 696                                         if (tr && !tr->can_internal_playback_seek (frame_delta)) {
 697                                                 ok = false;
 698                                                 break;
 699                                         }
 700                                 }
 701
 702                                 if (ok) {
 703                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 704                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 705                                                 if (tr) {
 706                                                         tr->internal_playback_seek (frame_delta);
 707                                                 }
 708                                         }
 709                                         _transport_frame += frame_delta;
 710
 711                                 } else {
 712                                         cerr << "cannot micro-seek\n";
 713                                         /* XXX what? */
 714                                 }
 715
 716                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 717                                 average_slave_delta = 0L;
 718                                 this_delta = 0;
 719                         }
 720                 }
 721
 722                 if (_slave_state == Running && _transport_speed == 0.0f) {
 723                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 724                         start_transport ();
 725                 }
 726
 727         } else { // slave_speed is 0
 728
 729                 /* slave has stopped */
 730
 731                 if (_transport_speed != 0.0f) {
 732                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 733                         stop_transport ();
 734                 }
 735
 736                 if (slave_transport_frame != _transport_frame) {
 737                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 738                         force_locate (slave_transport_frame, false);
 739                 }
 740
 741                 _slave_state = Stopped;
 742         }
 743 }
 744
 745 void
 746 Session::follow_slave_silently (pframes_t nframes, float slave_speed)
 747 {
 748         if (slave_speed && _transport_speed) {
 749
 750                 /* something isn't right, but we should move with the master
 751                    for now.
 752                 */
 753
 754                 bool need_butler;
 755
 756                 silent_process_routes (nframes, need_butler);
 757
 758                 get_track_statistics ();
 759
 760                 if (need_butler) {
 761                         _butler->summon ();
 762                 }
 763
 764                 int32_t frames_moved = (int32_t) floor (_transport_speed * nframes);
 765
 766                 if (frames_moved < 0) {
 767                         decrement_transport_position (-frames_moved);
 768                 } else {
 769                         increment_transport_position (frames_moved);
 770                 }
 771
 772                 framepos_t stop_limit;
 773
 774                 if (actively_recording()) {
 775                         stop_limit = max_framepos;
 776                 } else {
 777                         if (Config->get_stop_at_session_end()) {
 778                                 stop_limit = current_end_frame();
 779                         } else {
 780                                 stop_limit = max_framepos;
 781                         }
 782                 }
 783
 784                 maybe_stop (stop_limit);
 785         }
 786 }
 787
 788 void
 789 Session::process_without_events (pframes_t nframes)
 790 {
 791         bool session_needs_butler = false;
 792         framepos_t stop_limit;
 793         framecnt_t frames_moved;
 794
 795         if (!process_can_proceed()) {
 796                 _silent = true;
 797                 return;
 798         }
 799
 800         if (!_exporting && _slave) {
 801                 if (!follow_slave (nframes)) {
 802                         return;
 803                 }
 804         }
 805
 806         if (_transport_speed == 0) {
 807                 fail_roll (nframes);
 808                 return;
 809         }
 810
 811         if (_transport_speed == 1.0) {
 812                 frames_moved = (framecnt_t) nframes;
 813         } else {
 814                 interpolation.set_target_speed (fabs(_target_transport_speed));
 815                 interpolation.set_speed (fabs(_transport_speed));
 816                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 817         }
 818
 819         if (!_exporting && !timecode_transmission_suspended()) {
 820                 send_midi_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, nframes);
 821         }
 822
 823         if (actively_recording()) {
 824                 stop_limit = max_framepos;
 825         } else {
 826                 if (Config->get_stop_at_session_end()) {
 827                         stop_limit = current_end_frame();
 828                 } else {
 829                         stop_limit = max_framepos;
 830                 }
 831         }
 832
 833         if (maybe_stop (stop_limit)) {
 834                 fail_roll (nframes);
 835                 return;
 836         }
 837
 838         if (maybe_sync_start (nframes)) {
 839                 return;
 840         }
 841
 842         click (_transport_frame, nframes);
 843
 844         if (process_routes (nframes, session_needs_butler)) {
 845                 fail_roll (nframes);
 846                 return;
 847         }
 848
 849         get_track_statistics ();
 850
 851         /* XXX: I'm not sure whether this is correct, but at least it
 852            matches process_with_events, so that this new frames_moved
 853            is -ve when transport speed is -ve.  This means that the
 854            transport position is updated correctly when we are in
 855            reverse.  It seems a bit wrong that we're not using the
 856            interpolator to compute this.
 857         */
 858
 859         frames_moved = (framecnt_t) floor (_transport_speed * nframes);
 860
 861         if (frames_moved < 0) {
 862                 decrement_transport_position (-frames_moved);
 863         } else {
 864                 increment_transport_position (frames_moved);
 865         }
 866
 867         maybe_stop (stop_limit);
 868         check_declick_out ();
 869
 870         if (session_needs_butler) {
 871                 _butler->summon ();
 872         }
 873 }
 874
 875 /** Process callback used when the auditioner is active.
 876  * @param nframes number of frames to process.
 877  */
 878 void
 879 Session::process_audition (pframes_t nframes)
 880 {
 881         SessionEvent* ev;
 882         boost::shared_ptr<RouteList> r = routes.reader ();
 883
 884         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 885                 if (!(*i)->is_hidden()) {
 886                         (*i)->silence (nframes);
 887                 }
 888         }
 889
 890         /* run the auditioner, and if it says we need butler service, ask for it */
 891
 892         if (auditioner->play_audition (nframes) > 0) {
 893                 _butler->summon ();
 894         }
 895
 896         /* if using a monitor section, run it because otherwise we don't hear anything */
 897
 898         if (auditioner->needs_monitor()) {
 899                 _monitor_out->passthru (_transport_frame, _transport_frame + nframes, nframes, false);
 900         }
 901
 902         /* handle pending events */
 903
 904         while (pending_events.read (&ev, 1) == 1) {
 905                 merge_event (ev);
 906         }
 907
 908         /* if we are not in the middle of a state change,
 909            and there are immediate events queued up,
 910            process them.
 911         */
 912
 913         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 914                 SessionEvent *ev = immediate_events.front ();
 915                 immediate_events.pop_front ();
 916                 process_event (ev);
 917         }
 918
 919         if (!auditioner->auditioning()) {
 920                 /* auditioner no longer active, so go back to the normal process callback */
 921                 process_function = &Session::process_with_events;
 922         }
 923 }
 924
 925 bool
 926 Session::maybe_sync_start (pframes_t & nframes)
 927 {
 928         pframes_t sync_offset;
 929
 930         if (!waiting_for_sync_offset) {
 931                 return false;
 932         }
 933
 934         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 935
 936                 /* generate silence up to the sync point, then
 937                    adjust nframes + offset to reflect whatever
 938                    is left to do.
 939                 */
 940
 941                 no_roll (sync_offset);
 942                 nframes -= sync_offset;
 943                 Port::increment_global_port_buffer_offset (sync_offset);
 944                 waiting_for_sync_offset = false;
 945
 946                 if (nframes == 0) {
 947                         return true; // done, nothing left to process
 948                 }
 949
 950         } else {
 951
 952                 /* sync offset point is not within this process()
 953                    cycle, so just generate silence. and don't bother
 954                    with any fancy stuff here, just the minimal silence.
 955                 */
 956
 957                 _silent = true;
 958
 959                 if (Config->get_locate_while_waiting_for_sync()) {
 960                         if (micro_locate (nframes)) {
 961                                 /* XXX ERROR !!! XXX */
 962                         }
 963                 }
 964
 965                 return true; // done, nothing left to process
 966         }
 967
 968         return false;
 969 }
 970
 971 void
 972 Session::queue_event (SessionEvent* ev)
 973 {
 974         if (_state_of_the_state & Deletion) {
 975                 return;
 976         } else if (_state_of_the_state & Loading) {
 977                 merge_event (ev);
 978         } else {
 979                 pending_events.write (&ev, 1);
 980         }
 981 }
 982
 983 void
 984 Session::set_next_event ()
 985 {
 986         if (events.empty()) {
 987                 next_event = events.end();
 988                 return;
 989         }
 990
 991         if (next_event == events.end()) {
 992                 next_event = events.begin();
 993         }
 994
 995         if ((*next_event)->action_frame > _transport_frame) {
 996                 next_event = events.begin();
 997         }
 998
 999         for (; next_event != events.end(); ++next_event) {
1000                 if ((*next_event)->action_frame >= _transport_frame) {
1001                         break;
1002                 }
1003         }
1004 }
1005
1006 void
1007 Session::process_event (SessionEvent* ev)
1008 {
1009         bool remove = true;
1010         bool del = true;
1011
1012         /* if we're in the middle of a state change (i.e. waiting
1013            for the butler thread to complete the non-realtime
1014            part of the change), we'll just have to queue this
1015            event for a time when the change is complete.
1016         */
1017
1018         if (non_realtime_work_pending()) {
1019
1020                 /* except locates, which we have the capability to handle */
1021
1022                 if (ev->type != SessionEvent::Locate) {
1023                         immediate_events.insert (immediate_events.end(), ev);
1024                         _remove_event (ev);
1025                         return;
1026                 }
1027         }
1028
1029         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
1030
1031         switch (ev->type) {
1032         case SessionEvent::SetLoop:
1033                 set_play_loop (ev->yes_or_no);
1034                 break;
1035
1036         case SessionEvent::AutoLoop:
1037                 if (play_loop) {
1038                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
1039                 }
1040                 remove = false;
1041                 del = false;
1042                 break;
1043
1044         case SessionEvent::Locate:
1045                 if (ev->yes_or_no) {
1046                         // cerr << "forced locate to " << ev->target_frame << endl;
1047                         locate (ev->target_frame, false, true, false);
1048                 } else {
1049                         // cerr << "soft locate to " << ev->target_frame << endl;
1050                         start_locate (ev->target_frame, false, true, false);
1051                 }
1052                 _send_timecode_update = true;
1053                 break;
1054
1055         case SessionEvent::LocateRoll:
1056                 if (ev->yes_or_no) {
1057                         // cerr << "forced locate to+roll " << ev->target_frame << endl;
1058                         locate (ev->target_frame, true, true, false);
1059                 } else {
1060                         // cerr << "soft locate to+roll " << ev->target_frame << endl;
1061                         start_locate (ev->target_frame, true, true, false);
1062                 }
1063                 _send_timecode_update = true;
1064                 break;
1065
1066         case SessionEvent::LocateRollLocate:
1067                 // locate is handled by ::request_roll_at_and_return()
1068                 _requested_return_frame = ev->target_frame;
1069                 request_locate (ev->target2_frame, true);
1070                 break;
1071
1072
1073         case SessionEvent::SetTransportSpeed:
1074                 set_transport_speed (ev->speed, ev->yes_or_no, ev->second_yes_or_no);
1075                 break;
1076
1077         case SessionEvent::PunchIn:
1078                 // cerr << "PunchIN at " << transport_frame() << endl;
1079                 if (config.get_punch_in() && record_status() == Enabled) {
1080                         enable_record ();
1081                 }
1082                 remove = false;
1083                 del = false;
1084                 break;
1085
1086         case SessionEvent::PunchOut:
1087                 // cerr << "PunchOUT at " << transport_frame() << endl;
1088                 if (config.get_punch_out()) {
1089                         step_back_from_record ();
1090                 }
1091                 remove = false;
1092                 del = false;
1093                 break;
1094
1095         case SessionEvent::StopOnce:
1096                 if (!non_realtime_work_pending()) {
1097                         stop_transport (ev->yes_or_no);
1098                         _clear_event_type (SessionEvent::StopOnce);
1099                 }
1100                 remove = false;
1101                 del = false;
1102                 break;
1103
1104         case SessionEvent::RangeStop:
1105                 if (!non_realtime_work_pending()) {
1106                         stop_transport (ev->yes_or_no);
1107                 }
1108                 remove = false;
1109                 del = false;
1110                 break;
1111
1112         case SessionEvent::RangeLocate:
1113                 start_locate (ev->target_frame, true, true, false);
1114                 remove = false;
1115                 del = false;
1116                 break;
1117
1118         case SessionEvent::Overwrite:
1119                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1120                 break;
1121
1122         case SessionEvent::SetTrackSpeed:
1123                 set_track_speed (static_cast<Track*> (ev->ptr), ev->speed);
1124                 break;
1125
1126         case SessionEvent::SetSyncSource:
1127                 use_sync_source (ev->slave);
1128                 break;
1129
1130         case SessionEvent::Audition:
1131                 set_audition (ev->region);
1132                 // drop reference to region
1133                 ev->region.reset ();
1134                 break;
1135
1136         case SessionEvent::InputConfigurationChange:
1137                 add_post_transport_work (PostTransportInputChange);
1138                 _butler->schedule_transport_work ();
1139                 break;
1140
1141         case SessionEvent::SetPlayAudioRange:
1142                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1143                 break;
1144
1145         case SessionEvent::RealTimeOperation:
1146                 process_rtop (ev);
1147                 del = false; // other side of RT request needs to clean up
1148                 break;
1149
1150         case SessionEvent::AdjustPlaybackBuffering:
1151                 schedule_playback_buffering_adjustment ();
1152                 break;
1153
1154         case SessionEvent::AdjustCaptureBuffering:
1155                 schedule_capture_buffering_adjustment ();
1156                 break;
1157
1158         case SessionEvent::SetTimecodeTransmission:
1159                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1160                 break;
1161
1162         default:
1163           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1164                 /*NOTREACHED*/
1165                 break;
1166         };
1167
1168         if (remove) {
1169                 del = del && !_remove_event (ev);
1170         }
1171
1172         if (del) {
1173                 delete ev;
1174         }
1175 }
1176