2 Copyright (C) 2002 Paul Davis
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.
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.
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.
20 #ifndef __ardour_transport_master_h__
21 #define __ardour_transport_master_h__
25 #include <boost/optional.hpp>
26 #include <boost/atomic.hpp>
28 #include <glibmm/threads.h>
29 #include <glibmm/timer.h>
34 #include "pbd/properties.h"
35 #include "pbd/signals.h"
36 #include "pbd/stateful.h"
38 #include "temporal/time.h"
40 #include "ardour/libardour_visibility.h"
41 #include "ardour/region.h" /* for Properties::locked */
42 #include "ardour/types.h"
44 #include "midi++/parser.h"
45 #include "midi++/types.h"
47 /* used for delta_string(): */
48 #define PLUSMINUS(A) ( ((A)<0) ? "-" : (((A)>0) ? "+" : "\u00B1") )
49 #define LEADINGZERO(A) ( (A)<10 ? " " : (A)<100 ? " " : (A)<1000 ? " " : "" )
61 namespace Properties {
62 LIBARDOUR_API extern PBD::PropertyDescriptor<bool> fr2997;
63 LIBARDOUR_API extern PBD::PropertyDescriptor<bool> collect;
64 LIBARDOUR_API extern PBD::PropertyDescriptor<bool> connected;
65 LIBARDOUR_API extern PBD::PropertyDescriptor<bool> sclock_synced;
66 LIBARDOUR_API extern PBD::PropertyDescriptor<ARDOUR::TransportRequestType> allowed_transport_requests;
69 struct LIBARDOUR_API SafeTime {
71 /* This object uses memory fences to provide psuedo-atomic updating of
72 * non-atomic data. If after reading guard1 and guard2 with correct
73 * memory fencing they have the same value, then we know that the other
74 * members are all internally consistent.
76 * Traditionally, one might do this with a mutex, but this object
77 * provides lock-free write update. The reader might block while
78 * waiting for consistency, but this is extraordinarily unlikely. In
79 * this sense, the design is similar to a spinlock.
81 * any update starts by incrementing guard1, with a memory fence to
82 * ensure no reordering of this w.r.t later operations.
84 * then we update the "non-atomic" data members.
86 * then we update guard2, with another memory fence to prevent
89 * ergo, if guard1 == guard2, the update of the non-atomic members is
90 * complete and the values stored there are consistent.
93 boost::atomic<int> guard1;
95 samplepos_t timestamp;
97 boost::atomic<int> guard2;
115 void update (samplepos_t p, samplepos_t t, double s) {
116 guard1.fetch_add (1, boost::memory_order_acquire);
120 guard2.fetch_add (1, boost::memory_order_acquire);
123 void safe_read (SafeTime& dst) const {
128 std::cerr << X_("SafeTime: atomic read of current time failed, sleeping!") << std::endl;
132 dst.guard1.store (guard1.load (boost::memory_order_seq_cst), boost::memory_order_seq_cst);
133 dst.position = position;
134 dst.timestamp = timestamp;
136 dst.guard2.store (guard2.load (boost::memory_order_seq_cst), boost::memory_order_seq_cst);
139 } while (dst.guard1.load (boost::memory_order_seq_cst) != dst.guard2.load (boost::memory_order_seq_cst));
144 * @class TransportMaster
146 * @brief The TransportMaster interface can be used to sync ARDOURs tempo to an external source
147 * like MTC, MIDI Clock, etc. as well as a single internal pseudo master we
148 * call "UI" because it is controlled from any of the user interfaces for
149 * Ardour (GUI, control surfaces, OSC, etc.)
152 class LIBARDOUR_API TransportMaster : public PBD::Stateful {
155 TransportMaster (SyncSource t, std::string const & name);
156 virtual ~TransportMaster();
158 static boost::shared_ptr<TransportMaster> factory (SyncSource, std::string const &, bool removeable);
159 static boost::shared_ptr<TransportMaster> factory (XMLNode const &);
161 virtual void pre_process (pframes_t nframes, samplepos_t now, boost::optional<samplepos_t>) = 0;
164 * This is the most important function to implement:
165 * Each process cycle, Session::follow_slave will call this method.
166 * and after the method call they should
168 * Session::follow_slave will then try to follow the given
169 * <em>position</em> using a delay locked loop (DLL),
170 * starting with the first given transport speed.
171 * If the values of speed and position contradict each other,
172 * ARDOUR will always follow the position and disregard the speed.
173 * Although, a correct speed is important so that ARDOUR
174 * can sync to the master time source quickly.
176 * For background information on delay locked loops,
177 * see http://www.kokkinizita.net/papers/usingdll.pdf
179 * The method has the following precondition:
182 * TransportMaster::ok() should return true, otherwise playback will stop
183 * immediately and the method will not be called
186 * when the references speed and position are passed into the TransportMaster
187 * they are uninitialized
191 * After the method call the following postconditions should be met:
194 * The first position value on transport start should be 0,
195 * otherwise ARDOUR will try to locate to the new position
196 * rather than move to it
199 * the references speed and position should be assigned
200 * to the TransportMasters current requested transport speed
201 * and transport position.
204 * TransportMaster::resolution() should be greater than the maximum distance of
205 * ARDOURs transport position to the slaves requested transport position.
207 * <li>TransportMaster::locked() should return true, otherwise Session::no_roll will be called</li>
208 * <li>TransportMaster::starting() should be false, otherwise the transport will not move until it becomes true</li> *
211 * @param speed - The transport speed requested
212 * @param position - The transport position requested
213 * @return - The return value is currently ignored (see Session::follow_slave)
215 virtual bool speed_and_position (double& speed, samplepos_t& position, samplepos_t & lp, samplepos_t & when, samplepos_t now);
218 * reports to ARDOUR whether the TransportMaster is currently synced to its external
221 * @return - when returning false, the transport will stop rolling
223 virtual bool locked() const = 0;
226 * reports to ARDOUR whether the slave is in a sane state
228 * @return - when returning false, the transport will be stopped and the slave
229 * disconnected from ARDOUR.
231 virtual bool ok() const = 0;
234 * reports to ARDOUR whether the slave is in the process of starting
237 * @return - when returning false, transport will not move until this method returns true
239 virtual bool starting() const { return false; }
242 * @return - the timing resolution of the TransportMaster - If the distance of ARDOURs transport
243 * to the slave becomes greater than the resolution, sound will stop
245 virtual samplecnt_t resolution() const = 0;
248 * @return - the expected update interval for the data source used by
249 * this transport master. Even if the data is effectively continuous,
250 * this number indicates how long it is between changes to the known
251 * position of the master.
253 virtual samplecnt_t update_interval() const = 0;
256 * @return - when returning true, ARDOUR will wait for seekahead_distance() before transport
259 virtual bool requires_seekahead () const = 0;
262 * @return the number of samples that this slave wants to seek ahead. Relevant
263 * only if requires_seekahead() returns true.
266 virtual samplecnt_t seekahead_distance() const { return 0; }
269 * @return - when returning true, ARDOUR will use transport speed 1.0 no matter what
272 virtual bool sample_clock_synced() const { return _sclock_synced; }
273 virtual void set_sample_clock_synced (bool);
276 * @return - current time-delta between engine and sync-source
278 virtual std::string delta_string() const { return ""; }
280 sampleoffset_t current_delta() const { return _current_delta; }
282 /* this is intended to be used by a UI and polled from a timeout. it should
283 return a string describing the current position of the TC source. it
284 should NOT do any computation, but should use a cached value
285 of the TC source position.
287 virtual std::string position_string() const = 0;
289 virtual bool can_loop() const { return false; }
291 virtual Location* loop_location() const { return 0; }
292 bool has_loop() const { return loop_location() != 0; }
294 SyncSource type() const { return _type; }
295 TransportRequestSource request_type() const {
297 case Engine: /* also JACK */
306 return TRS_MIDIClock;
309 std::string name() const { return _name; }
310 void set_name (std::string const &);
312 int set_state (XMLNode const &, int);
313 XMLNode& get_state();
315 static const std::string state_node_name;
316 static void make_property_quarks ();
318 virtual void set_session (Session*);
320 boost::shared_ptr<Port> port() const { return _port; }
322 bool check_collect();
323 virtual void set_collect (bool);
324 bool collect() const { return _collect; }
326 /* called whenever the manager starts collecting (processing) this
327 transport master. Typically will re-initialize any state used to
328 deal with incoming data.
330 virtual void init() = 0;
332 virtual void check_backend() {}
333 virtual bool allow_request (TransportRequestSource, TransportRequestType) const;
335 TransportRequestType request_mask() const { return _request_mask; }
336 void set_request_mask (TransportRequestType);
338 void get_current (double&, samplepos_t&, samplepos_t);
340 /* this is set at construction, and not changeable later, so it is not
344 bool removeable () const { return _removeable; }
345 void set_removeable (bool yn) { _removeable = yn; }
347 std::string display_name (bool sh/*ort*/ = true) const;
351 PBD::Property<std::string> _name;
353 sampleoffset_t _current_delta;
354 bool _pending_collect;
356 PBD::Property<TransportRequestType> _request_mask; /* lists transport requests still accepted when we're in control */
357 PBD::Property<bool> _locked;
358 PBD::Property<bool> _sclock_synced;
359 PBD::Property<bool> _collect;
360 PBD::Property<bool> _connected;
364 /* DLL - chase incoming data */
366 int transport_direction;
374 boost::shared_ptr<Port> _port;
376 PBD::ScopedConnection port_connection;
377 bool connection_handler (boost::weak_ptr<ARDOUR::Port>, std::string name1, boost::weak_ptr<ARDOUR::Port>, std::string name2, bool yn);
379 PBD::ScopedConnection backend_connection;
381 virtual void register_properties ();
384 /** a helper class for any TransportMaster that receives its input via a MIDI
387 class LIBARDOUR_API TransportMasterViaMIDI {
389 boost::shared_ptr<MidiPort> midi_port() const { return _midi_port; }
390 boost::shared_ptr<Port> create_midi_port (std::string const & port_name);
393 TransportMasterViaMIDI () {};
396 boost::shared_ptr<MidiPort> _midi_port;
399 class LIBARDOUR_API TimecodeTransportMaster : public TransportMaster {
401 TimecodeTransportMaster (std::string const & name, SyncSource type);
403 virtual Timecode::TimecodeFormat apparent_timecode_format() const = 0;
404 samplepos_t timecode_offset;
405 bool timecode_negative_offset;
407 bool fr2997() const { return _fr2997; }
408 void set_fr2997 (bool);
411 void register_properties ();
414 PBD::Property<bool> _fr2997;
417 class LIBARDOUR_API MTC_TransportMaster : public TimecodeTransportMaster, public TransportMasterViaMIDI {
419 MTC_TransportMaster (std::string const &);
420 ~MTC_TransportMaster ();
422 void set_session (Session*);
424 void pre_process (pframes_t nframes, samplepos_t now, boost::optional<samplepos_t>);
428 void handle_locate (const MIDI::byte*);
430 samplecnt_t update_interval () const;
431 samplecnt_t resolution () const;
432 bool requires_seekahead () const { return false; }
433 samplecnt_t seekahead_distance() const;
436 Timecode::TimecodeFormat apparent_timecode_format() const;
437 std::string position_string() const;
438 std::string delta_string() const;
441 PBD::ScopedConnectionList port_connections;
442 PBD::ScopedConnection config_connection;
443 bool can_notify_on_unknown_rate;
445 static const int sample_tolerance;
447 samplepos_t mtc_frame; /* current time */
448 double mtc_frame_dll;
449 samplepos_t last_inbound_frame; /* when we got it; audio clocked */
450 MIDI::byte last_mtc_fps_byte;
451 samplepos_t window_begin;
452 samplepos_t window_end;
453 samplepos_t first_mtc_timestamp;
454 bool did_reset_tc_format;
455 Timecode::TimecodeFormat saved_tc_format;
456 Glib::Threads::Mutex reset_lock;
457 uint32_t reset_pending;
459 int transport_direction;
463 double speedup_due_to_tc_mismatch;
464 double quarter_frame_duration;
465 Timecode::TimecodeFormat mtc_timecode;
466 Timecode::TimecodeFormat a3e_timecode;
467 Timecode::Time timecode;
468 bool printed_timecode_warning;
470 void reset (bool with_pos);
471 void queue_reset (bool with_pos);
474 void update_mtc_qtr (MIDI::Parser&, int, samplepos_t);
475 void update_mtc_time (const MIDI::byte *, bool, samplepos_t);
476 void update_mtc_status (MIDI::MTC_Status);
477 void reset_window (samplepos_t);
478 bool outside_window (samplepos_t) const;
479 void init_mtc_dll(samplepos_t, double);
480 void parse_timecode_offset();
481 void parameter_changed(std::string const & p);
484 class LIBARDOUR_API LTC_TransportMaster : public TimecodeTransportMaster {
486 LTC_TransportMaster (std::string const &);
487 ~LTC_TransportMaster ();
489 void set_session (Session*);
491 void pre_process (pframes_t nframes, samplepos_t now, boost::optional<samplepos_t>);
496 samplecnt_t update_interval () const;
497 samplecnt_t resolution () const;
498 bool requires_seekahead () const { return false; }
499 samplecnt_t seekahead_distance () const { return 0; }
502 Timecode::TimecodeFormat apparent_timecode_format() const;
503 std::string position_string() const;
504 std::string delta_string() const;
507 void parse_ltc(const pframes_t, const Sample* const, const samplecnt_t);
508 void process_ltc(samplepos_t const);
509 void init_dll (samplepos_t, int32_t);
510 bool detect_discontinuity(LTCFrameExt *, int, bool);
511 bool detect_ltc_fps(int, bool);
512 bool equal_ltc_sample_time(LTCFrame *a, LTCFrame *b);
513 void reset (bool with_ts = true);
515 void resync_latency();
516 void parse_timecode_offset();
517 void parameter_changed(std::string const & p);
519 bool did_reset_tc_format;
520 Timecode::TimecodeFormat saved_tc_format;
522 LTCDecoder * decoder;
523 double samples_per_ltc_frame;
524 Timecode::Time timecode;
525 LTCFrameExt prev_sample;
528 samplecnt_t monotonic_cnt;
531 int ltc_detect_fps_cnt;
532 int ltc_detect_fps_max;
533 bool printed_timecode_warning;
534 bool sync_lock_broken;
535 Timecode::TimecodeFormat ltc_timecode;
536 Timecode::TimecodeFormat a3e_timecode;
537 double samples_per_timecode_frame;
539 PBD::ScopedConnectionList port_connections;
540 PBD::ScopedConnection config_connection;
541 LatencyRange ltc_slave_latency;
544 class LIBARDOUR_API MIDIClock_TransportMaster : public TransportMaster, public TransportMasterViaMIDI {
546 MIDIClock_TransportMaster (std::string const & name, int ppqn = 24);
548 /// Constructor for unit tests
549 ~MIDIClock_TransportMaster ();
551 void set_session (Session*);
553 void pre_process (pframes_t nframes, samplepos_t now, boost::optional<samplepos_t>);
555 void rebind (MidiPort&);
559 bool starting() const;
561 samplecnt_t update_interval () const;
562 samplecnt_t resolution () const;
563 bool requires_seekahead () const { return false; }
566 std::string position_string() const;
567 std::string delta_string() const;
569 float bpm() const { return _bpm; }
572 PBD::ScopedConnectionList port_connections;
574 /// pulses per quarter note for one MIDI clock sample (default 24)
577 /// the duration of one ppqn in sample time
578 double one_ppqn_in_samples;
580 /// the timestamp of the first MIDI clock message
581 samplepos_t first_timestamp;
583 /// the time stamp and should-be transport position of the last inbound MIDI clock message
584 samplepos_t last_timestamp;
585 double should_be_position;
587 /// the number of midi clock messages received (zero-based)
589 long midi_clock_count;
591 /// a DLL to track MIDI clock
598 void start (MIDI::Parser& parser, samplepos_t timestamp);
599 void contineu (MIDI::Parser& parser, samplepos_t timestamp);
600 void stop (MIDI::Parser& parser, samplepos_t timestamp);
601 void position (MIDI::Parser& parser, MIDI::byte* message, size_t size, samplepos_t timestamp);
602 // we can't use continue because it is a C++ keyword
603 void calculate_one_ppqn_in_samples_at(samplepos_t time);
604 samplepos_t calculate_song_position(uint16_t song_position_in_sixteenth_notes);
605 void calculate_filter_coefficients (double qpm);
606 void update_midi_clock (MIDI::Parser& parser, samplepos_t timestamp);
609 class LIBARDOUR_API Engine_TransportMaster : public TransportMaster
612 Engine_TransportMaster (AudioEngine&);
613 ~Engine_TransportMaster ();
615 void pre_process (pframes_t nframes, samplepos_t now, boost::optional<samplepos_t>);
616 bool speed_and_position (double& speed, samplepos_t& pos, samplepos_t &, samplepos_t &, samplepos_t);
618 bool starting() const { return _starting; }
621 samplecnt_t update_interval () const;
622 samplecnt_t resolution () const { return 1; }
623 bool requires_seekahead () const { return false; }
624 bool sample_clock_synced() const { return true; }
626 void check_backend();
627 bool allow_request (TransportRequestSource, TransportRequestType) const;
629 std::string position_string() const;
630 std::string delta_string() const;
639 #endif /* __ardour_transport_master_h__ */