libs/ardour/tempo.cc

   1 /*
   2     Copyright (C) 2000-2002 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 <algorithm>
  21 #include <stdexcept>
  22 #include <cmath>
  23
  24 #include <unistd.h>
  25
  26 #include <glibmm/threads.h>
  27
  28 #include "pbd/enumwriter.h"
  29 #include "pbd/xml++.h"
  30 #include "evoral/Beats.hpp"
  31
  32 #include "ardour/debug.h"
  33 #include "ardour/lmath.h"
  34 #include "ardour/tempo.h"
  35
  36 #include "i18n.h"
  37 #include <locale.h>
  38
  39 using namespace std;
  40 using namespace ARDOUR;
  41 using namespace PBD;
  42
  43 using Timecode::BBT_Time;
  44
  45 /* _default tempo is 4/4 qtr=120 */
  46
  47 Meter    TempoMap::_default_meter (4.0, 4.0);
  48 Tempo    TempoMap::_default_tempo (120.0);
  49
  50 /***********************************************************************/
  51
  52 double
  53 Meter::frames_per_grid (const Tempo& tempo, framecnt_t sr) const
  54 {
  55         /* This is tempo- and meter-sensitive. The number it returns
  56            is based on the interval between any two lines in the
  57            grid that is constructed from tempo and meter sections.
  58
  59            The return value IS NOT interpretable in terms of "beats".
  60         */
  61
  62         return (60.0 * sr) / (tempo.beats_per_minute() * (_note_type/tempo.note_type()));
  63 }
  64
  65 double
  66 Meter::frames_per_bar (const Tempo& tempo, framecnt_t sr) const
  67 {
  68         return frames_per_grid (tempo, sr) * _divisions_per_bar;
  69 }
  70
  71 /***********************************************************************/
  72
  73 const string TempoSection::xml_state_node_name = "Tempo";
  74
  75 TempoSection::TempoSection (const XMLNode& node)
  76         : MetricSection (0.0, 0, MusicTime)
  77         , Tempo (TempoMap::default_tempo())
  78         , _c_func (0.0)
  79         , _active (true)
  80         , _locked_to_meter (false)
  81 {
  82         XMLProperty const * prop;
  83         LocaleGuard lg;
  84         BBT_Time bbt;
  85         double pulse;
  86         uint32_t frame;
  87
  88         _legacy_bbt = BBT_Time (0, 0, 0);
  89
  90         if ((prop = node.property ("start")) != 0) {
  91                 if (sscanf (prop->value().c_str(), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
  92                             &bbt.bars,
  93                             &bbt.beats,
  94                             &bbt.ticks) == 3) {
  95                         /* legacy session - start used to be in bbt*/
  96                         _legacy_bbt = bbt;
  97                         pulse = -1.0;
  98                         info << _("Legacy session detected. TempoSection XML node will be altered.") << endmsg;
  99                 }
 100         }
 101
 102         if ((prop = node.property ("pulse")) != 0) {
 103                 if (sscanf (prop->value().c_str(), "%lf", &pulse) != 1) {
 104                         error << _("TempoSection XML node has an illegal \"pulse\" value") << endmsg;
 105                 }
 106         }
 107
 108         set_pulse (pulse);
 109
 110         if ((prop = node.property ("frame")) != 0) {
 111                 if (sscanf (prop->value().c_str(), "%" PRIu32, &frame) != 1) {
 112                         error << _("TempoSection XML node has an illegal \"frame\" value") << endmsg;
 113                 } else {
 114                         set_frame (frame);
 115                 }
 116         }
 117
 118         if ((prop = node.property ("beats-per-minute")) == 0) {
 119                 error << _("TempoSection XML node has no \"beats-per-minute\" property") << endmsg;
 120                 throw failed_constructor();
 121         }
 122
 123         if (sscanf (prop->value().c_str(), "%lf", &_beats_per_minute) != 1 || _beats_per_minute < 0.0) {
 124                 error << _("TempoSection XML node has an illegal \"beats_per_minute\" value") << endmsg;
 125                 throw failed_constructor();
 126         }
 127
 128         if ((prop = node.property ("note-type")) == 0) {
 129                 /* older session, make note type be quarter by default */
 130                 _note_type = 4.0;
 131         } else {
 132                 if (sscanf (prop->value().c_str(), "%lf", &_note_type) != 1 || _note_type < 1.0) {
 133                         error << _("TempoSection XML node has an illegal \"note-type\" value") << endmsg;
 134                         throw failed_constructor();
 135                 }
 136         }
 137
 138         if ((prop = node.property ("movable")) == 0) {
 139                 error << _("TempoSection XML node has no \"movable\" property") << endmsg;
 140                 throw failed_constructor();
 141         }
 142
 143         set_movable (string_is_affirmative (prop->value()));
 144
 145         if ((prop = node.property ("active")) == 0) {
 146                 warning << _("TempoSection XML node has no \"active\" property") << endmsg;
 147                 set_active(true);
 148         } else {
 149                 set_active (string_is_affirmative (prop->value()));
 150         }
 151
 152         if ((prop = node.property ("tempo-type")) == 0) {
 153                 _type = Constant;
 154         } else {
 155                 _type = Type (string_2_enum (prop->value(), _type));
 156         }
 157
 158         if ((prop = node.property ("lock-style")) == 0) {
 159                 if (movable()) {
 160                         set_position_lock_style (MusicTime);
 161                 } else {
 162                         set_position_lock_style (AudioTime);
 163                 }
 164         } else {
 165                 set_position_lock_style (PositionLockStyle (string_2_enum (prop->value(), position_lock_style())));
 166         }
 167
 168         if ((prop = node.property ("locked-to-meter")) == 0) {
 169                 set_locked_to_meter (false);
 170         } else {
 171                 set_locked_to_meter (string_is_affirmative (prop->value()));
 172         }
 173 }
 174
 175 XMLNode&
 176 TempoSection::get_state() const
 177 {
 178         XMLNode *root = new XMLNode (xml_state_node_name);
 179         char buf[256];
 180         LocaleGuard lg;
 181
 182         snprintf (buf, sizeof (buf), "%f", pulse());
 183         root->add_property ("pulse", buf);
 184         snprintf (buf, sizeof (buf), "%li", frame());
 185         root->add_property ("frame", buf);
 186         snprintf (buf, sizeof (buf), "%f", _beats_per_minute);
 187         root->add_property ("beats-per-minute", buf);
 188         snprintf (buf, sizeof (buf), "%f", _note_type);
 189         root->add_property ("note-type", buf);
 190         snprintf (buf, sizeof (buf), "%s", movable()?"yes":"no");
 191         root->add_property ("movable", buf);
 192         snprintf (buf, sizeof (buf), "%s", active()?"yes":"no");
 193         root->add_property ("active", buf);
 194         root->add_property ("tempo-type", enum_2_string (_type));
 195         root->add_property ("lock-style", enum_2_string (position_lock_style()));
 196         root->add_property ("locked-to-meter", locked_to_meter()?"yes":"no");
 197
 198         return *root;
 199 }
 200
 201 void
 202 TempoSection::set_type (Type type)
 203 {
 204         _type = type;
 205 }
 206
 207 /** returns the tempo in whole pulses per minute at the zero-based (relative to session) frame.
 208 */
 209 double
 210 TempoSection::tempo_at_frame (const framepos_t& f, const framecnt_t& frame_rate) const
 211 {
 212
 213         if (_type == Constant || _c_func == 0.0) {
 214                 return pulses_per_minute();
 215         }
 216
 217         return pulse_tempo_at_time (frame_to_minute (f - frame(), frame_rate));
 218 }
 219
 220 /** returns the zero-based frame (relative to session)
 221    where the tempo in whole pulses per minute occurs in this section.
 222    beat b is only used for constant tempos.
 223    note that the tempo map may have multiple such values.
 224 */
 225 framepos_t
 226 TempoSection::frame_at_tempo (const double& ppm, const double& b, const framecnt_t& frame_rate) const
 227 {
 228         if (_type == Constant || _c_func == 0.0) {
 229                 return ((b - pulse())  * frames_per_pulse (frame_rate))  + frame();
 230         }
 231
 232         return minute_to_frame (time_at_pulse_tempo (ppm), frame_rate) + frame();
 233 }
 234 /** returns the tempo in pulses per minute at the zero-based (relative to session) beat.
 235 */
 236 double
 237 TempoSection::tempo_at_pulse (const double& p) const
 238 {
 239
 240         if (_type == Constant || _c_func == 0.0) {
 241                 return pulses_per_minute();
 242         }
 243         double const ppm = pulse_tempo_at_pulse (p - pulse());
 244         return ppm;
 245 }
 246
 247 /** returns the zero-based beat (relative to session)
 248    where the tempo in whole pulses per minute occurs given frame f. frame f is only used for constant tempos.
 249    note that the session tempo map may have multiple beats at a given tempo.
 250 */
 251 double
 252 TempoSection::pulse_at_tempo (const double& ppm, const framepos_t& f, const framecnt_t& frame_rate) const
 253 {
 254         if (_type == Constant || _c_func == 0.0) {
 255                 double const pulses = ((f - frame()) / frames_per_pulse (frame_rate)) + pulse();
 256                 return  pulses;
 257         }
 258         return pulse_at_pulse_tempo (ppm) + pulse();
 259 }
 260
 261 /** returns the zero-based pulse (relative to session origin)
 262    where the zero-based frame (relative to session)
 263    lies.
 264 */
 265 double
 266 TempoSection::pulse_at_frame (const framepos_t& f, const framecnt_t& frame_rate) const
 267 {
 268         if (_type == Constant || _c_func == 0.0) {
 269                 return ((f - frame()) / frames_per_pulse (frame_rate)) + pulse();
 270         }
 271
 272         return pulse_at_time (frame_to_minute (f - frame(), frame_rate)) + pulse();
 273 }
 274
 275 /** returns the zero-based frame (relative to session start frame)
 276    where the zero-based pulse (relative to session start)
 277    falls.
 278 */
 279
 280 framepos_t
 281 TempoSection::frame_at_pulse (const double& p, const framecnt_t& frame_rate) const
 282 {
 283         if (_type == Constant || _c_func == 0.0) {
 284                 return (framepos_t) floor ((p - pulse()) * frames_per_pulse (frame_rate)) + frame();
 285         }
 286
 287         return minute_to_frame (time_at_pulse (p - pulse()), frame_rate) + frame();
 288 }
 289
 290 /*
 291 Ramp Overview
 292
 293       |                     *
 294 Tempo |                   *
 295 Tt----|-----------------*|
 296 Ta----|--------------|*  |
 297       |            * |   |
 298       |         *    |   |
 299       |     *        |   |
 300 T0----|*             |   |
 301   *   |              |   |
 302       _______________|___|____
 303       time           a   t (next tempo)
 304       [        c         ] defines c
 305
 306 Duration in beats at time a is the integral of some Tempo function.
 307 In our case, the Tempo function (Tempo at time t) is
 308 T(t) = T0(e^(ct))
 309
 310 with function constant
 311 c = log(Ta/T0)/a
 312 so
 313 a = log(Ta/T0)/c
 314
 315 The integral over t of our Tempo function (the beat function, which is the duration in beats at some time t) is:
 316 b(t) = T0(e^(ct) - 1) / c
 317
 318 To find the time t at beat duration b, we use the inverse function of the beat function (the time function) which can be shown to be:
 319 t(b) = log((c.b / T0) + 1) / c
 320
 321 The time t at which Tempo T occurs is a as above:
 322 t(T) = log(T / T0) / c
 323
 324 The beat at which a Tempo T occurs is:
 325 b(T) = (T - T0) / c
 326
 327 The Tempo at which beat b occurs is:
 328 T(b) = b.c + T0
 329
 330 We define c for this tempo ramp by placing a new tempo section at some time t after this one.
 331 Our problem is that we usually don't know t.
 332 We almost always know the duration in beats between this and the new section, so we need to find c in terms of the beat function.
 333 Where a = t (i.e. when a is equal to the time of the next tempo section), the beat function reveals:
 334 t = b log (Ta / T0) / (T0 (e^(log (Ta / T0)) - 1))
 335
 336 By substituting our expanded t as a in the c function above, our problem is reduced to:
 337 c = T0 (e^(log (Ta / T0)) - 1) / b
 338
 339 Of course the word 'beat' has been left loosely defined above.
 340 In music, a beat is defined by the musical pulse (which comes from the tempo)
 341 and the meter in use at a particular time (how many  pulse divisions there are in one bar).
 342 It would be more accurate to substitute the work 'pulse' for 'beat' above.
 343
 344 Anyway ...
 345
 346 We can now store c for future time calculations.
 347 If the following tempo section (the one that defines c in conjunction with this one)
 348 is changed or moved, c is no longer valid.
 349
 350 The public methods are session-relative.
 351
 352 Most of this stuff is taken from this paper:
 353
 354 WHERE’S THE BEAT?
 355 TOOLS FOR DYNAMIC TEMPO CALCULATIONS
 356 Jan C. Schacher
 357 Martin Neukom
 358 Zurich University of Arts
 359 Institute for Computer Music and Sound Technology
 360
 361 https://www.zhdk.ch/fileadmin/data_subsites/data_icst/Downloads/Timegrid/ICST_Tempopolyphony_ICMC07.pdf
 362
 363 */
 364
 365 /*
 366   compute this ramp's function constant using the end tempo (in whole pulses per minute)
 367   and duration (pulses into global start) of some later tempo section.
 368 */
 369 double
 370 TempoSection::compute_c_func_pulse (const double& end_bpm, const double& end_pulse, const framecnt_t& frame_rate)
 371 {
 372         double const log_tempo_ratio = log (end_bpm / pulses_per_minute());
 373         return pulses_per_minute() *  (expm1 (log_tempo_ratio)) / (end_pulse - pulse());
 374 }
 375
 376 /* compute the function constant from some later tempo section, given tempo (whole pulses/min.) and distance (in frames) from session origin */
 377 double
 378 TempoSection::compute_c_func_frame (const double& end_bpm, const framepos_t& end_frame, const framecnt_t& frame_rate) const
 379 {
 380         return c_func (end_bpm, frame_to_minute (end_frame - frame(), frame_rate));
 381 }
 382
 383 framepos_t
 384 TempoSection::minute_to_frame (const double& time, const framecnt_t& frame_rate) const
 385 {
 386         return (framepos_t) floor ((time * 60.0 * frame_rate) + 0.5);
 387 }
 388
 389 double
 390 TempoSection::frame_to_minute (const framepos_t& frame, const framecnt_t& frame_rate) const
 391 {
 392         return (frame / (double) frame_rate) / 60.0;
 393 }
 394
 395 /* position function */
 396 double
 397 TempoSection::a_func (double end_ppm, double c_func) const
 398 {
 399         return log (end_ppm / pulses_per_minute()) /  c_func;
 400 }
 401
 402 /*function constant*/
 403 double
 404 TempoSection::c_func (double end_ppm, double end_time) const
 405 {
 406         return log (end_ppm / pulses_per_minute()) /  end_time;
 407 }
 408
 409 /* tempo in ppm at time in minutes */
 410 double
 411 TempoSection::pulse_tempo_at_time (const double& time) const
 412 {
 413         return exp (_c_func * time) * pulses_per_minute();
 414 }
 415
 416 /* time in minutes at tempo in ppm */
 417 double
 418 TempoSection::time_at_pulse_tempo (const double& pulse_tempo) const
 419 {
 420         return log (pulse_tempo / pulses_per_minute()) / _c_func;
 421 }
 422
 423 /* tick at tempo in ppm */
 424 double
 425 TempoSection::pulse_at_pulse_tempo (const double& pulse_tempo) const
 426 {
 427         return (pulse_tempo - pulses_per_minute()) / _c_func;
 428 }
 429
 430 /* tempo in ppm at tick */
 431 double
 432 TempoSection::pulse_tempo_at_pulse (const double& pulse) const
 433 {
 434         return (pulse * _c_func) + pulses_per_minute();
 435 }
 436
 437 /* pulse at time in minutes */
 438 double
 439 TempoSection::pulse_at_time (const double& time) const
 440 {
 441         return expm1 (_c_func * time) * (pulses_per_minute() / _c_func);
 442 }
 443
 444 /* time in minutes at pulse */
 445 double
 446 TempoSection::time_at_pulse (const double& pulse) const
 447 {
 448         return log1p ((_c_func * pulse) / pulses_per_minute()) / _c_func;
 449 }
 450
 451 /***********************************************************************/
 452
 453 const string MeterSection::xml_state_node_name = "Meter";
 454
 455 MeterSection::MeterSection (const XMLNode& node)
 456         : MetricSection (0.0, 0, MusicTime), Meter (TempoMap::default_meter())
 457 {
 458         XMLProperty const * prop;
 459         LocaleGuard lg;
 460         BBT_Time bbt;
 461         double pulse = 0.0;
 462         double beat = 0.0;
 463         framepos_t frame = 0;
 464         pair<double, BBT_Time> start;
 465
 466         if ((prop = node.property ("start")) != 0) {
 467                 if (sscanf (prop->value().c_str(), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
 468                     &bbt.bars,
 469                     &bbt.beats,
 470                     &bbt.ticks) < 3) {
 471                         error << _("MeterSection XML node has an illegal \"start\" value") << endmsg;
 472                 } else {
 473                         /* legacy session - start used to be in bbt*/
 474                         info << _("Legacy session detected - MeterSection XML node will be altered.") << endmsg;
 475                         pulse = -1.0;
 476                 }
 477         }
 478
 479         if ((prop = node.property ("pulse")) != 0) {
 480                 if (sscanf (prop->value().c_str(), "%lf", &pulse) != 1) {
 481                         error << _("MeterSection XML node has an illegal \"pulse\" value") << endmsg;
 482                 }
 483         }
 484         set_pulse (pulse);
 485
 486         if ((prop = node.property ("beat")) != 0) {
 487                 if (sscanf (prop->value().c_str(), "%lf", &beat) != 1) {
 488                         error << _("MeterSection XML node has an illegal \"beat\" value") << endmsg;
 489                 }
 490         }
 491
 492         start.first = beat;
 493
 494         if ((prop = node.property ("bbt")) == 0) {
 495                 warning << _("MeterSection XML node has no \"bbt\" property") << endmsg;
 496         } else if (sscanf (prop->value().c_str(), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
 497                     &bbt.bars,
 498                     &bbt.beats,
 499                     &bbt.ticks) < 3) {
 500                 error << _("MeterSection XML node has an illegal \"bbt\" value") << endmsg;
 501                 throw failed_constructor();
 502         }
 503
 504         start.second = bbt;
 505         set_beat (start);
 506
 507         if ((prop = node.property ("frame")) != 0) {
 508                 if (sscanf (prop->value().c_str(), "%li", &frame) != 1) {
 509                         error << _("MeterSection XML node has an illegal \"frame\" value") << endmsg;
 510                 } else {
 511                         set_frame (frame);
 512                 }
 513         }
 514
 515         /* beats-per-bar is old; divisions-per-bar is new */
 516
 517         if ((prop = node.property ("divisions-per-bar")) == 0) {
 518                 if ((prop = node.property ("beats-per-bar")) == 0) {
 519                         error << _("MeterSection XML node has no \"beats-per-bar\" or \"divisions-per-bar\" property") << endmsg;
 520                         throw failed_constructor();
 521                 }
 522         }
 523         if (sscanf (prop->value().c_str(), "%lf", &_divisions_per_bar) != 1 || _divisions_per_bar < 0.0) {
 524                 error << _("MeterSection XML node has an illegal \"divisions-per-bar\" value") << endmsg;
 525                 throw failed_constructor();
 526         }
 527
 528         if ((prop = node.property ("note-type")) == 0) {
 529                 error << _("MeterSection XML node has no \"note-type\" property") << endmsg;
 530                 throw failed_constructor();
 531         }
 532         if (sscanf (prop->value().c_str(), "%lf", &_note_type) != 1 || _note_type < 0.0) {
 533                 error << _("MeterSection XML node has an illegal \"note-type\" value") << endmsg;
 534                 throw failed_constructor();
 535         }
 536
 537         if ((prop = node.property ("movable")) == 0) {
 538                 error << _("MeterSection XML node has no \"movable\" property") << endmsg;
 539                 throw failed_constructor();
 540         }
 541
 542         set_movable (string_is_affirmative (prop->value()));
 543
 544         if ((prop = node.property ("lock-style")) == 0) {
 545                 warning << _("MeterSection XML node has no \"lock-style\" property") << endmsg;
 546                 if (movable()) {
 547                         set_position_lock_style (MusicTime);
 548                 } else {
 549                         set_position_lock_style (AudioTime);
 550                 }
 551         } else {
 552                 set_position_lock_style (PositionLockStyle (string_2_enum (prop->value(), position_lock_style())));
 553         }
 554 }
 555
 556 XMLNode&
 557 MeterSection::get_state() const
 558 {
 559         XMLNode *root = new XMLNode (xml_state_node_name);
 560         char buf[256];
 561         LocaleGuard lg;
 562
 563         snprintf (buf, sizeof (buf), "%lf", pulse());
 564         root->add_property ("pulse", buf);
 565         snprintf (buf, sizeof (buf), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
 566                   bbt().bars,
 567                   bbt().beats,
 568                   bbt().ticks);
 569         root->add_property ("bbt", buf);
 570         snprintf (buf, sizeof (buf), "%lf", beat());
 571         root->add_property ("beat", buf);
 572         snprintf (buf, sizeof (buf), "%f", _note_type);
 573         root->add_property ("note-type", buf);
 574         snprintf (buf, sizeof (buf), "%li", frame());
 575         root->add_property ("frame", buf);
 576         root->add_property ("lock-style", enum_2_string (position_lock_style()));
 577         snprintf (buf, sizeof (buf), "%f", _divisions_per_bar);
 578         root->add_property ("divisions-per-bar", buf);
 579         snprintf (buf, sizeof (buf), "%s", movable()?"yes":"no");
 580         root->add_property ("movable", buf);
 581
 582         return *root;
 583 }
 584
 585 /***********************************************************************/
 586 /*
 587   Tempo Map Overview
 588
 589   Tempo is the rate of the musical pulse.
 590   Meters divide the pulses into measures and beats.
 591
 592   Note that Tempo::beats_per_minute() has nothing to do with musical beats.
 593   It should rather be thought of as tempo note divisions per minute.
 594
 595   TempoSections, which are nice to think of in whole pulses per minute,
 596   and MeterSecions which divide tempo pulses into measures (via divisions_per_bar)
 597   and beats (via note_divisor) are used to form a tempo map.
 598   TempoSections and MeterSections may be locked to either audio or music (position lock style).
 599   We construct the tempo map by first using the frame or pulse position (depending on position lock style) of each tempo.
 600   We then use this pulse/frame layout to find the beat & pulse or frame position of each meter (again depending on lock style).
 601
 602   Having done this, we can now find any one of tempo, beat, frame or pulse if a beat, frame, pulse or tempo is known.
 603
 604   With tepo sections potentially being ramped, meters provide a way of mapping beats to whole pulses without
 605   referring to the tempo function(s) involved as the distance in whole pulses between a meter and a subsequent beat is
 606   sb->beat() - meter->beat() / meter->note_divisor().
 607   Because every meter falls on a known pulse, (derived from its bar), the rest is easy as the duration in pulses between
 608   two meters is of course
 609   (meater_b->bar - meter_a->bar) * meter_a->divisions_per_bar / meter_a->note_divisor.
 610
 611   Below, beat calculations are based on meter sections and all pulse and tempo calculations are based on tempo sections.
 612   Beat to frame conversion of course requires the use of meter and tempo.
 613
 614   Remembering that ramped tempo sections interact, it is important to avoid referring to any other tempos when moving tempo sections,
 615   Here, beats (meters) are used to determine the new pulse (see predict_tempo_position())
 616
 617   The first tempo and first meter are special. they must move together, and must be locked to audio.
 618   Audio locked tempos which lie before the first meter are made inactive.
 619   They will be re-activated if the first meter is again placed before them.
 620
 621   Both tempos and meters have a pulse position and a frame position.
 622   Meters also have a beat position, which is always 0.0 for the first meter.
 623
 624   A tempo locked to music is locked to musical pulses.
 625   A meter locked to music is locked to beats.
 626
 627   Recomputing the tempo map is the process where the 'missing' position
 628   (tempo pulse or meter pulse & beat in the case of AudioTime, frame for MusicTime) is calculated.
 629
 630   It is important to keep the _metrics in an order that makes sense.
 631   Because ramped MusicTime and AudioTime tempos can interact with each other,
 632   reordering is frequent. Care must be taken to keep _metrics in a solved state.
 633   Solved means ordered by frame or pulse with frame-accurate precision (see check_solved()).
 634 */
 635 struct MetricSectionSorter {
 636     bool operator() (const MetricSection* a, const MetricSection* b) {
 637             return a->pulse() < b->pulse();
 638     }
 639 };
 640
 641 struct MetricSectionFrameSorter {
 642     bool operator() (const MetricSection* a, const MetricSection* b) {
 643             return a->frame() < b->frame();
 644     }
 645 };
 646
 647 TempoMap::TempoMap (framecnt_t fr)
 648 {
 649         _frame_rate = fr;
 650         BBT_Time start (1, 1, 0);
 651
 652         TempoSection *t = new TempoSection (0.0, 0, _default_tempo.beats_per_minute(), _default_tempo.note_type(), TempoSection::Constant, AudioTime);
 653         MeterSection *m = new MeterSection (0.0, 0, 0.0, start, _default_meter.divisions_per_bar(), _default_meter.note_divisor(), AudioTime);
 654
 655         t->set_movable (false);
 656         m->set_movable (false);
 657
 658         /* note: frame time is correct (zero) for both of these */
 659
 660         _metrics.push_back (t);
 661         _metrics.push_back (m);
 662
 663 }
 664
 665 TempoMap::~TempoMap ()
 666 {
 667         Metrics::const_iterator d = _metrics.begin();
 668         while (d != _metrics.end()) {
 669                 delete (*d);
 670                 ++d;
 671         }
 672         _metrics.clear();
 673 }
 674
 675 void
 676 TempoMap::remove_tempo (const TempoSection& tempo, bool complete_operation)
 677 {
 678         bool removed = false;
 679
 680         {
 681                 Glib::Threads::RWLock::WriterLock lm (lock);
 682                 if ((removed = remove_tempo_locked (tempo))) {
 683                         if (complete_operation) {
 684                                 recompute_map (_metrics);
 685                         }
 686                 }
 687         }
 688
 689         if (removed && complete_operation) {
 690                 PropertyChanged (PropertyChange ());
 691         }
 692 }
 693
 694 bool
 695 TempoMap::remove_tempo_locked (const TempoSection& tempo)
 696 {
 697         Metrics::iterator i;
 698
 699         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
 700                 if (dynamic_cast<TempoSection*> (*i) != 0) {
 701                         if (tempo.frame() == (*i)->frame()) {
 702                                 if ((*i)->movable()) {
 703                                         delete (*i);
 704                                         _metrics.erase (i);
 705                                         return true;
 706                                 }
 707                         }
 708                 }
 709         }
 710
 711         return false;
 712 }
 713
 714 void
 715 TempoMap::remove_meter (const MeterSection& tempo, bool complete_operation)
 716 {
 717         bool removed = false;
 718
 719         {
 720                 Glib::Threads::RWLock::WriterLock lm (lock);
 721                 if ((removed = remove_meter_locked (tempo))) {
 722                         if (complete_operation) {
 723                                 recompute_map (_metrics);
 724                         }
 725                 }
 726         }
 727
 728         if (removed && complete_operation) {
 729                 PropertyChanged (PropertyChange ());
 730         }
 731 }
 732
 733 bool
 734 TempoMap::remove_meter_locked (const MeterSection& meter)
 735 {
 736         Metrics::iterator i;
 737
 738         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
 739                 TempoSection* t = 0;
 740                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
 741                         if (meter.frame() == (*i)->frame()) {
 742                                 if (t->locked_to_meter()) {
 743                                         delete (*i);
 744                                         _metrics.erase (i);
 745                                         break;
 746                                 }
 747                         }
 748                 }
 749         }
 750
 751         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
 752                 if (dynamic_cast<MeterSection*> (*i) != 0) {
 753                         if (meter.frame() == (*i)->frame()) {
 754                                 if ((*i)->movable()) {
 755                                         delete (*i);
 756                                         _metrics.erase (i);
 757                                         return true;
 758                                 }
 759                         }
 760                 }
 761         }
 762
 763         return false;
 764 }
 765
 766 void
 767 TempoMap::do_insert (MetricSection* section)
 768 {
 769         bool need_add = true;
 770         /* we only allow new meters to be inserted on beat 1 of an existing
 771          * measure.
 772          */
 773         MeterSection* m = 0;
 774         if ((m = dynamic_cast<MeterSection*>(section)) != 0) {
 775
 776                 if ((m->bbt().beats != 1) || (m->bbt().ticks != 0)) {
 777
 778                         pair<double, BBT_Time> corrected = make_pair (m->beat(), m->bbt());
 779                         corrected.second.beats = 1;
 780                         corrected.second.ticks = 0;
 781                         corrected.first = beat_at_bbt_locked (_metrics, corrected.second);
 782                         warning << string_compose (_("Meter changes can only be positioned on the first beat of a bar. Moving from %1 to %2"),
 783                                                    m->bbt(), corrected.second) << endmsg;
 784                         //m->set_pulse (corrected);
 785                 }
 786         }
 787
 788         /* Look for any existing MetricSection that is of the same type and
 789            in the same bar as the new one, and remove it before adding
 790            the new one. Note that this means that if we find a matching,
 791            existing section, we can break out of the loop since we're
 792            guaranteed that there is only one such match.
 793         */
 794
 795         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
 796
 797                 TempoSection* const tempo = dynamic_cast<TempoSection*> (*i);
 798                 TempoSection* const insert_tempo = dynamic_cast<TempoSection*> (section);
 799                 MeterSection* const meter = dynamic_cast<MeterSection*> (*i);
 800                 MeterSection* const insert_meter = dynamic_cast<MeterSection*> (section);
 801
 802                 if (tempo && insert_tempo) {
 803
 804                         /* Tempo sections */
 805                         bool const ipm = insert_tempo->position_lock_style() == MusicTime;
 806                         if ((ipm && tempo->pulse() == insert_tempo->pulse()) || (!ipm && tempo->frame() == insert_tempo->frame())) {
 807
 808                                 if (!tempo->movable()) {
 809
 810                                         /* can't (re)move this section, so overwrite
 811                                          * its data content (but not its properties as
 812                                          * a section).
 813                                          */
 814
 815                                         *(dynamic_cast<Tempo*>(*i)) = *(dynamic_cast<Tempo*>(insert_tempo));
 816                                         (*i)->set_position_lock_style (AudioTime);
 817                                         TempoSection* t;
 818                                         if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
 819                                                 t->set_type (insert_tempo->type());
 820                                         }
 821                                         need_add = false;
 822                                 } else {
 823                                         delete (*i);
 824                                         _metrics.erase (i);
 825                                 }
 826                                 break;
 827                         }
 828
 829                 } else if (meter && insert_meter) {
 830
 831                         /* Meter Sections */
 832
 833                         bool const ipm = insert_meter->position_lock_style() == MusicTime;
 834
 835                         if ((ipm && meter->beat() == insert_meter->beat()) || (!ipm && meter->frame() == insert_meter->frame())) {
 836
 837                                 if (!meter->movable()) {
 838
 839                                         /* can't (re)move this section, so overwrite
 840                                          * its data content (but not its properties as
 841                                          * a section
 842                                          */
 843
 844                                         *(dynamic_cast<Meter*>(*i)) = *(dynamic_cast<Meter*>(insert_meter));
 845                                         (*i)->set_position_lock_style (AudioTime);
 846                                         need_add = false;
 847                                 } else {
 848                                         delete (*i);
 849                                         _metrics.erase (i);
 850                                 }
 851
 852                                 break;
 853                         }
 854                 } else {
 855                         /* non-matching types, so we don't care */
 856                 }
 857         }
 858
 859         /* Add the given MetricSection, if we didn't just reset an existing
 860          * one above
 861          */
 862
 863         if (need_add) {
 864                 MeterSection* const insert_meter = dynamic_cast<MeterSection*> (section);
 865                 TempoSection* const insert_tempo = dynamic_cast<TempoSection*> (section);
 866                 Metrics::iterator i;
 867                 if (insert_meter) {
 868                         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
 869                                 MeterSection* const meter = dynamic_cast<MeterSection*> (*i);
 870
 871                                 if (meter) {
 872                                         bool const ipm = insert_meter->position_lock_style() == MusicTime;
 873                                         if ((ipm && meter->beat() > insert_meter->beat()) || (!ipm && meter->frame() > insert_meter->frame())) {
 874                                                 break;
 875                                         }
 876                                 }
 877                         }
 878                 } else if (insert_tempo) {
 879                         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
 880                                 TempoSection* const tempo = dynamic_cast<TempoSection*> (*i);
 881
 882                                 if (tempo) {
 883                                         bool const ipm = insert_tempo->position_lock_style() == MusicTime;
 884                                         if ((ipm && tempo->pulse() > insert_tempo->pulse()) || (!ipm && tempo->frame() > insert_tempo->frame())) {
 885                                                 break;
 886                                         }
 887                                 }
 888                         }
 889                 }
 890
 891                 _metrics.insert (i, section);
 892                 //dump (_metrics, std::cout);
 893         }
 894 }
 895
 896 TempoSection*
 897 TempoMap::add_tempo (const Tempo& tempo, const double& pulse, const framepos_t& frame, ARDOUR::TempoSection::Type type, PositionLockStyle pls)
 898 {
 899         TempoSection* ts = 0;
 900         {
 901                 Glib::Threads::RWLock::WriterLock lm (lock);
 902                 ts = add_tempo_locked (tempo, pulse, frame, type, pls, true);
 903         }
 904
 905
 906         PropertyChanged (PropertyChange ());
 907
 908         return ts;
 909 }
 910
 911 void
 912 TempoMap::replace_tempo (const TempoSection& ts, const Tempo& tempo, const double& pulse, const framepos_t& frame, TempoSection::Type type, PositionLockStyle pls)
 913 {
 914         const bool locked_to_meter = ts.locked_to_meter();
 915
 916         {
 917                 Glib::Threads::RWLock::WriterLock lm (lock);
 918                 TempoSection& first (first_tempo());
 919                 if (ts.frame() != first.frame()) {
 920                         remove_tempo_locked (ts);
 921                         add_tempo_locked (tempo, pulse, frame, type, pls, true, locked_to_meter);
 922                 } else {
 923                         first.set_type (type);
 924                         first.set_pulse (0.0);
 925                         first.set_frame (frame);
 926                         first.set_position_lock_style (AudioTime);
 927                         {
 928                                 /* cannot move the first tempo section */
 929                                 *static_cast<Tempo*>(&first) = tempo;
 930                                 recompute_map (_metrics);
 931                         }
 932                 }
 933         }
 934
 935         PropertyChanged (PropertyChange ());
 936 }
 937
 938 TempoSection*
 939 TempoMap::add_tempo_locked (const Tempo& tempo, double pulse, framepos_t frame
 940                             , TempoSection::Type type, PositionLockStyle pls, bool recompute, bool locked_to_meter)
 941 {
 942         TempoSection* t = new TempoSection (pulse, frame, tempo.beats_per_minute(), tempo.note_type(), type, pls);
 943         t->set_locked_to_meter (locked_to_meter);
 944
 945         do_insert (t);
 946
 947         if (recompute) {
 948                 if (pls == AudioTime) {
 949                         solve_map_frame (_metrics, t, t->frame());
 950                 } else {
 951                         solve_map_pulse (_metrics, t, t->pulse());
 952                 }
 953                 recompute_meters (_metrics);
 954         }
 955
 956         return t;
 957 }
 958
 959 MeterSection*
 960 TempoMap::add_meter (const Meter& meter, const double& beat, const Timecode::BBT_Time& where, const framepos_t& frame, PositionLockStyle pls)
 961 {
 962         MeterSection* m = 0;
 963         {
 964                 Glib::Threads::RWLock::WriterLock lm (lock);
 965                 m = add_meter_locked (meter, beat, where, frame, pls, true);
 966         }
 967
 968
 969 #ifndef NDEBUG
 970         if (DEBUG_ENABLED(DEBUG::TempoMap)) {
 971                 dump (_metrics, std::cerr);
 972         }
 973 #endif
 974
 975         PropertyChanged (PropertyChange ());
 976         return m;
 977 }
 978
 979 void
 980 TempoMap::replace_meter (const MeterSection& ms, const Meter& meter, const BBT_Time& where, const framepos_t& frame, PositionLockStyle pls)
 981 {
 982         {
 983                 Glib::Threads::RWLock::WriterLock lm (lock);
 984                 const double beat = beat_at_bbt_locked (_metrics, where);
 985
 986                 if (ms.movable()) {
 987                         remove_meter_locked (ms);
 988                         add_meter_locked (meter, beat, where, frame, pls, true);
 989                 } else {
 990                         MeterSection& first (first_meter());
 991                         TempoSection& first_t (first_tempo());
 992                         /* cannot move the first meter section */
 993                         *static_cast<Meter*>(&first) = meter;
 994                         first.set_position_lock_style (AudioTime);
 995                         first.set_pulse (0.0);
 996                         first.set_frame (frame);
 997                         pair<double, BBT_Time> beat = make_pair (0.0, BBT_Time (1, 1, 0));
 998                         first.set_beat (beat);
 999                         first_t.set_frame (first.frame());
1000                         first_t.set_pulse (0.0);
1001                         first_t.set_position_lock_style (AudioTime);
1002                 }
1003                 recompute_map (_metrics);
1004         }
1005         PropertyChanged (PropertyChange ());
1006 }
1007
1008 MeterSection*
1009 TempoMap::add_meter_locked (const Meter& meter, double beat, const Timecode::BBT_Time& where, framepos_t frame, PositionLockStyle pls, bool recompute)
1010 {
1011         const MeterSection& prev_m = meter_section_at_locked  (_metrics, frame - 1);
1012         const double pulse = ((where.bars - prev_m.bbt().bars) * (prev_m.divisions_per_bar() / prev_m.note_divisor())) + prev_m.pulse();
1013
1014         if (pls == AudioTime) {
1015                 /* add meter-locked tempo */
1016                 add_tempo_locked (tempo_at_locked (_metrics, frame), pulse,  frame, TempoSection::Ramp, AudioTime, true, true);
1017         }
1018
1019         MeterSection* new_meter = new MeterSection (pulse, frame, beat, where, meter.divisions_per_bar(), meter.note_divisor(), pls);
1020
1021         do_insert (new_meter);
1022
1023         if (recompute) {
1024
1025                 if (pls == AudioTime) {
1026                         solve_map_frame (_metrics, new_meter, frame);
1027                 } else {
1028                         solve_map_bbt (_metrics, new_meter, where);
1029                 }
1030         }
1031
1032         return new_meter;
1033 }
1034
1035 void
1036 TempoMap::change_initial_tempo (double beats_per_minute, double note_type)
1037 {
1038         Tempo newtempo (beats_per_minute, note_type);
1039         TempoSection* t;
1040
1041         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1042                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1043                         if (!t->active()) {
1044                                 continue;
1045                         }
1046                         {
1047                                 Glib::Threads::RWLock::WriterLock lm (lock);
1048                                 *((Tempo*) t) = newtempo;
1049                                 recompute_map (_metrics);
1050                         }
1051                         PropertyChanged (PropertyChange ());
1052                         break;
1053                 }
1054         }
1055 }
1056
1057 void
1058 TempoMap::change_existing_tempo_at (framepos_t where, double beats_per_minute, double note_type)
1059 {
1060         Tempo newtempo (beats_per_minute, note_type);
1061
1062         TempoSection* prev;
1063         TempoSection* first;
1064         Metrics::iterator i;
1065
1066         /* find the TempoSection immediately preceding "where"
1067          */
1068
1069         for (first = 0, i = _metrics.begin(), prev = 0; i != _metrics.end(); ++i) {
1070
1071                 if ((*i)->frame() > where) {
1072                         break;
1073                 }
1074
1075                 TempoSection* t;
1076
1077                 if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
1078                         if (!t->active()) {
1079                                 continue;
1080                         }
1081                         if (!first) {
1082                                 first = t;
1083                         }
1084                         prev = t;
1085                 }
1086         }
1087
1088         if (!prev) {
1089                 if (!first) {
1090                         error << string_compose (_("no tempo sections defined in tempo map - cannot change tempo @ %1"), where) << endmsg;
1091                         return;
1092                 }
1093
1094                 prev = first;
1095         }
1096
1097         /* reset */
1098
1099         {
1100                 Glib::Threads::RWLock::WriterLock lm (lock);
1101                 /* cannot move the first tempo section */
1102                 *((Tempo*)prev) = newtempo;
1103                 recompute_map (_metrics);
1104         }
1105
1106         PropertyChanged (PropertyChange ());
1107 }
1108
1109 const MeterSection&
1110 TempoMap::first_meter () const
1111 {
1112         const MeterSection *m = 0;
1113
1114         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1115                 if ((m = dynamic_cast<const MeterSection *> (*i)) != 0) {
1116                         return *m;
1117                 }
1118         }
1119
1120         fatal << _("programming error: no meter section in tempo map!") << endmsg;
1121         abort(); /*NOTREACHED*/
1122         return *m;
1123 }
1124
1125 MeterSection&
1126 TempoMap::first_meter ()
1127 {
1128         MeterSection *m = 0;
1129
1130         /* CALLER MUST HOLD LOCK */
1131
1132         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1133                 if ((m = dynamic_cast<MeterSection *> (*i)) != 0) {
1134                         return *m;
1135                 }
1136         }
1137
1138         fatal << _("programming error: no tempo section in tempo map!") << endmsg;
1139         abort(); /*NOTREACHED*/
1140         return *m;
1141 }
1142
1143 const TempoSection&
1144 TempoMap::first_tempo () const
1145 {
1146         const TempoSection *t = 0;
1147
1148         /* CALLER MUST HOLD LOCK */
1149
1150         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1151                 if ((t = dynamic_cast<const TempoSection *> (*i)) != 0) {
1152                         if (!t->active()) {
1153                                 continue;
1154                         }
1155                         if (!t->movable()) {
1156                                 return *t;
1157                         }
1158                 }
1159         }
1160
1161         fatal << _("programming error: no tempo section in tempo map!") << endmsg;
1162         abort(); /*NOTREACHED*/
1163         return *t;
1164 }
1165
1166 TempoSection&
1167 TempoMap::first_tempo ()
1168 {
1169         TempoSection *t = 0;
1170
1171         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1172                 if ((t = dynamic_cast<TempoSection *> (*i)) != 0) {
1173                         if (!t->active()) {
1174                                 continue;
1175                         }
1176                         if (!t->movable()) {
1177                                 return *t;
1178                         }
1179                 }
1180         }
1181
1182         fatal << _("programming error: no tempo section in tempo map!") << endmsg;
1183         abort(); /*NOTREACHED*/
1184         return *t;
1185 }
1186 void
1187 TempoMap::recompute_tempos (Metrics& metrics)
1188 {
1189         TempoSection* prev_t = 0;
1190
1191         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1192                 TempoSection* t;
1193
1194                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1195                         if (!t->active()) {
1196                                 continue;
1197                         }
1198                         if (!t->movable()) {
1199                                 if (!prev_t) {
1200                                         t->set_pulse (0.0);
1201                                         prev_t = t;
1202                                         continue;
1203                                 }
1204                         }
1205                         if (prev_t) {
1206                                 if (t->position_lock_style() == AudioTime) {
1207                                         prev_t->set_c_func (prev_t->compute_c_func_frame (t->pulses_per_minute(), t->frame(), _frame_rate));
1208                                         if (!t->locked_to_meter()) {
1209                                                 t->set_pulse (prev_t->pulse_at_tempo (t->pulses_per_minute(), t->frame(), _frame_rate));
1210                                         }
1211
1212                                 } else {
1213                                         prev_t->set_c_func (prev_t->compute_c_func_pulse (t->pulses_per_minute(), t->pulse(), _frame_rate));
1214                                         t->set_frame (prev_t->frame_at_tempo (t->pulses_per_minute(), t->pulse(), _frame_rate));
1215
1216                                 }
1217                         }
1218                         prev_t = t;
1219                 }
1220         }
1221         prev_t->set_c_func (0.0);
1222 }
1223
1224 /* tempos must be positioned correctly.
1225    the current approach is to use a meter's bbt time as its base position unit.
1226    an audio-locked meter requires a recomputation of pulse and beat (but not bbt),
1227    while a music-locked meter requires recomputations of frame pulse and beat (but not bbt)
1228 */
1229 void
1230 TempoMap::recompute_meters (Metrics& metrics)
1231 {
1232         MeterSection* meter = 0;
1233         MeterSection* prev_m = 0;
1234
1235         for (Metrics::const_iterator mi = metrics.begin(); mi != metrics.end(); ++mi) {
1236                 if ((meter = dynamic_cast<MeterSection*> (*mi)) != 0) {
1237                         if (meter->position_lock_style() == AudioTime) {
1238                                 double pulse = 0.0;
1239                                 pair<double, BBT_Time> b_bbt;
1240                                 TempoSection* meter_locked_tempo = 0;
1241                                 for (Metrics::const_iterator ii = metrics.begin(); ii != metrics.end(); ++ii) {
1242                                         TempoSection* t;
1243                                         if ((t = dynamic_cast<TempoSection*> (*ii)) != 0) {
1244                                                 if ((t->locked_to_meter() || !t->movable()) && t->frame() == meter->frame()) {
1245                                                         meter_locked_tempo = t;
1246                                                         break;
1247                                                 }
1248                                         }
1249                                 }
1250
1251                                 if (prev_m) {
1252                                         const double beats = (meter->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar();
1253                                         if (beats + prev_m->beat() != meter->beat()) {
1254                                                 /* reordering caused a bbt change */
1255                                                 b_bbt = make_pair (beats + prev_m->beat()
1256                                                                    , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
1257                                                 pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
1258
1259                                         } else if (meter->movable()) {
1260                                                 b_bbt = make_pair (meter->beat(), meter->bbt());
1261                                                 pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
1262                                         }
1263                                 } else {
1264                                         b_bbt = make_pair (0.0, BBT_Time (1, 1, 0));
1265                                 }
1266                                 if (meter_locked_tempo) {
1267                                         meter_locked_tempo->set_pulse (pulse);
1268                                 }
1269                                 meter->set_beat (b_bbt);
1270                                 meter->set_pulse (pulse);
1271
1272                         } else {
1273                                 /* MusicTime */
1274                                 double pulse = 0.0;
1275                                 pair<double, BBT_Time> new_beat;
1276                                 if (prev_m) {
1277                                         const double beats = (meter->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar();
1278                                         if (beats + prev_m->beat() != meter->beat()) {
1279                                                 /* reordering caused a bbt change */
1280                                                 new_beat = make_pair (beats + prev_m->beat()
1281                                                                    , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
1282                                         } else {
1283                                                 new_beat = make_pair (beats + prev_m->beat(), meter->bbt());
1284                                         }
1285                                         pulse = (beats / prev_m->note_divisor()) + prev_m->pulse();
1286                                 } else {
1287                                         /* shouldn't happen - the first is audio-locked */
1288                                         pulse = pulse_at_beat_locked (metrics, meter->beat());
1289                                         new_beat = make_pair (meter->beat(), meter->bbt());
1290                                 }
1291
1292                                 meter->set_beat (new_beat);
1293                                 meter->set_pulse (pulse);
1294                                 meter->set_frame (frame_at_pulse_locked (metrics, pulse));
1295                         }
1296
1297                         prev_m = meter;
1298                 }
1299         }
1300 }
1301
1302 void
1303 TempoMap::recompute_map (Metrics& metrics, framepos_t end)
1304 {
1305         /* CALLER MUST HOLD WRITE LOCK */
1306
1307         if (end < 0) {
1308
1309                 /* we will actually stop once we hit
1310                    the last metric.
1311                 */
1312                 end = max_framepos;
1313
1314         }
1315
1316         DEBUG_TRACE (DEBUG::TempoMath, string_compose ("recomputing tempo map, zero to %1\n", end));
1317
1318         if (end == 0) {
1319                 /* silly call from Session::process() during startup
1320                  */
1321                 return;
1322         }
1323
1324         recompute_tempos (metrics);
1325         recompute_meters (metrics);
1326 }
1327
1328 TempoMetric
1329 TempoMap::metric_at (framepos_t frame, Metrics::const_iterator* last) const
1330 {
1331         Glib::Threads::RWLock::ReaderLock lm (lock);
1332         TempoMetric m (first_meter(), first_tempo());
1333
1334         /* at this point, we are *guaranteed* to have m.meter and m.tempo pointing
1335            at something, because we insert the default tempo and meter during
1336            TempoMap construction.
1337
1338            now see if we can find better candidates.
1339         */
1340
1341         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1342
1343                 if ((*i)->frame() > frame) {
1344                         break;
1345                 }
1346
1347                 m.set_metric(*i);
1348
1349                 if (last) {
1350                         *last = i;
1351                 }
1352         }
1353
1354         return m;
1355 }
1356
1357 /* XX meters only */
1358 TempoMetric
1359 TempoMap::metric_at (BBT_Time bbt) const
1360 {
1361         Glib::Threads::RWLock::ReaderLock lm (lock);
1362         TempoMetric m (first_meter(), first_tempo());
1363
1364         /* at this point, we are *guaranteed* to have m.meter and m.tempo pointing
1365            at something, because we insert the default tempo and meter during
1366            TempoMap construction.
1367
1368            now see if we can find better candidates.
1369         */
1370
1371         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1372                 MeterSection* mw;
1373                 if ((mw = dynamic_cast<MeterSection*> (*i)) != 0) {
1374                         BBT_Time section_start (mw->bbt());
1375
1376                         if (section_start.bars > bbt.bars || (section_start.bars == bbt.bars && section_start.beats > bbt.beats)) {
1377                                 break;
1378                         }
1379
1380                         m.set_metric (*i);
1381                 }
1382         }
1383
1384         return m;
1385 }
1386
1387 double
1388 TempoMap::pulse_at_beat (const double& beat) const
1389 {
1390         Glib::Threads::RWLock::ReaderLock lm (lock);
1391         return pulse_at_beat_locked (_metrics, beat);
1392 }
1393
1394 double
1395 TempoMap::pulse_at_beat_locked (const Metrics& metrics, const double& beat) const
1396 {
1397         MeterSection* prev_m = 0;
1398
1399         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1400                 MeterSection* m;
1401                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1402                         if (prev_m && m->beat() > beat) {
1403                                 break;
1404                         }
1405                         prev_m = m;
1406                 }
1407
1408         }
1409         double const ret = prev_m->pulse() + ((beat - prev_m->beat()) / prev_m->note_divisor());
1410         return ret;
1411 }
1412
1413 double
1414 TempoMap::beat_at_pulse (const double& pulse) const
1415 {
1416         Glib::Threads::RWLock::ReaderLock lm (lock);
1417         return beat_at_pulse_locked (_metrics, pulse);
1418 }
1419
1420 double
1421 TempoMap::beat_at_pulse_locked (const Metrics& metrics, const double& pulse) const
1422 {
1423         MeterSection* prev_m = 0;
1424
1425         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1426                 MeterSection* m;
1427                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1428                         if (prev_m && m->pulse() > pulse) {
1429                                 if (((pulse - prev_m->pulse()) * prev_m->note_divisor()) + prev_m->beat() > m->beat()) {
1430                                         break;
1431                                 }
1432                         }
1433                         prev_m = m;
1434                 }
1435         }
1436
1437         double const ret = ((pulse - prev_m->pulse()) * prev_m->note_divisor()) + prev_m->beat();
1438         return ret;
1439 }
1440
1441 double
1442 TempoMap::pulse_at_frame (const framecnt_t& frame) const
1443 {
1444         Glib::Threads::RWLock::ReaderLock lm (lock);
1445         return pulse_at_frame_locked (_metrics, frame);
1446 }
1447
1448 /* tempo section based */
1449 double
1450 TempoMap::pulse_at_frame_locked (const Metrics& metrics, const framecnt_t& frame) const
1451 {
1452         /* HOLD (at least) THE READER LOCK */
1453         TempoSection* prev_t = 0;
1454
1455         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1456                 TempoSection* t;
1457                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1458                         if (!t->active()) {
1459                                 continue;
1460                         }
1461                         if (prev_t && t->frame() > frame) {
1462                                 /*the previous ts is the one containing the frame */
1463                                 const double ret = prev_t->pulse_at_frame (frame, _frame_rate);
1464                                 return ret;
1465                         }
1466                         prev_t = t;
1467                 }
1468         }
1469
1470         /* treated as constant for this ts */
1471         const double pulses_in_section = (frame - prev_t->frame()) / prev_t->frames_per_pulse (_frame_rate);
1472
1473         return pulses_in_section + prev_t->pulse();
1474 }
1475
1476 framecnt_t
1477 TempoMap::frame_at_pulse (const double& pulse) const
1478 {
1479         Glib::Threads::RWLock::ReaderLock lm (lock);
1480         return frame_at_pulse_locked (_metrics, pulse);
1481 }
1482
1483 /* tempo section based */
1484 framecnt_t
1485 TempoMap::frame_at_pulse_locked (const Metrics& metrics, const double& pulse) const
1486 {
1487         /* HOLD THE READER LOCK */
1488
1489         const TempoSection* prev_t = 0;
1490
1491         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1492                 TempoSection* t;
1493
1494                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1495                         if (!t->active()) {
1496                                 continue;
1497                         }
1498                         if (prev_t && t->pulse() > pulse) {
1499                                 return prev_t->frame_at_pulse (pulse, _frame_rate);
1500                         }
1501
1502                         prev_t = t;
1503                 }
1504         }
1505         /* must be treated as constant, irrespective of _type */
1506         double const pulses_in_section = pulse - prev_t->pulse();
1507         double const dtime = pulses_in_section * prev_t->frames_per_pulse (_frame_rate);
1508
1509         framecnt_t const ret = (framecnt_t) floor (dtime) + prev_t->frame();
1510
1511         return ret;
1512 }
1513
1514 double
1515 TempoMap::beat_at_frame (const framecnt_t& frame) const
1516 {
1517         Glib::Threads::RWLock::ReaderLock lm (lock);
1518         return beat_at_frame_locked (_metrics, frame);
1519 }
1520
1521 /* meter / tempo section based */
1522 double
1523 TempoMap::beat_at_frame_locked (const Metrics& metrics, const framecnt_t& frame) const
1524 {
1525         const TempoSection& ts = tempo_section_at_locked (metrics, frame);
1526         MeterSection* prev_m = 0;
1527         MeterSection* next_m = 0;
1528
1529         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1530                 MeterSection* m;
1531                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1532                         if (prev_m && m->frame() > frame) {
1533                                 next_m = m;
1534                                 break;
1535                         }
1536                         prev_m = m;
1537                 }
1538         }
1539         if (frame < prev_m->frame()) {
1540                 return 0.0;
1541         }
1542         const double beat = prev_m->beat() + (ts.pulse_at_frame (frame, _frame_rate) - prev_m->pulse()) * prev_m->note_divisor();
1543
1544         if (next_m && next_m->beat() < beat) {
1545                 return next_m->beat();
1546         }
1547
1548         return beat;
1549 }
1550
1551 framecnt_t
1552 TempoMap::frame_at_beat (const double& beat) const
1553 {
1554         Glib::Threads::RWLock::ReaderLock lm (lock);
1555         return frame_at_beat_locked (_metrics, beat);
1556 }
1557
1558 /* meter section based */
1559 framecnt_t
1560 TempoMap::frame_at_beat_locked (const Metrics& metrics, const double& beat) const
1561 {
1562         const TempoSection& prev_t = tempo_section_at_beat_locked (metrics, beat);
1563         MeterSection* prev_m = 0;
1564
1565         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1566                 MeterSection* m;
1567                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1568                         if (prev_m && m->beat() > beat) {
1569                                 break;
1570                         }
1571                         prev_m = m;
1572                 }
1573         }
1574
1575         return prev_t.frame_at_pulse (((beat - prev_m->beat()) / prev_m->note_divisor()) + prev_m->pulse(), _frame_rate);
1576 }
1577
1578 double
1579 TempoMap::beat_at_bbt (const Timecode::BBT_Time& bbt)
1580 {
1581         Glib::Threads::RWLock::ReaderLock lm (lock);
1582         return beat_at_bbt_locked (_metrics, bbt);
1583 }
1584
1585
1586 double
1587 TempoMap::beat_at_bbt_locked (const Metrics& metrics, const Timecode::BBT_Time& bbt) const
1588 {
1589         /* CALLER HOLDS READ LOCK */
1590
1591         MeterSection* prev_m = 0;
1592
1593         /* because audio-locked meters have 'fake' integral beats,
1594            there is no pulse offset here.
1595         */
1596         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1597                 MeterSection* m;
1598                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1599                         if (prev_m) {
1600                                 const double bars_to_m = (m->beat() - prev_m->beat()) / prev_m->divisions_per_bar();
1601                                 if ((bars_to_m + (prev_m->bbt().bars - 1)) > (bbt.bars - 1)) {
1602                                         break;
1603                                 }
1604                         }
1605                         prev_m = m;
1606                 }
1607         }
1608
1609         const double remaining_bars = bbt.bars - prev_m->bbt().bars;
1610         const double remaining_bars_in_beats = remaining_bars * prev_m->divisions_per_bar();
1611         const double ret = remaining_bars_in_beats + prev_m->beat() + (bbt.beats - 1) + (bbt.ticks / BBT_Time::ticks_per_beat);
1612
1613         return ret;
1614 }
1615
1616 Timecode::BBT_Time
1617 TempoMap::bbt_at_beat (const double& beats)
1618 {
1619         Glib::Threads::RWLock::ReaderLock lm (lock);
1620         return bbt_at_beat_locked (_metrics, beats);
1621 }
1622
1623 Timecode::BBT_Time
1624 TempoMap::bbt_at_beat_locked (const Metrics& metrics, const double& b) const
1625 {
1626         /* CALLER HOLDS READ LOCK */
1627         MeterSection* prev_m = 0;
1628         const double beats = max (0.0, b);
1629
1630         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1631                 MeterSection* m = 0;
1632
1633                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1634                         if (prev_m) {
1635                                 if (m->beat() > beats) {
1636                                         /* this is the meter after the one our beat is on*/
1637                                         break;
1638                                 }
1639                         }
1640
1641                         prev_m = m;
1642                 }
1643         }
1644
1645         const double beats_in_ms = beats - prev_m->beat();
1646         const uint32_t bars_in_ms = (uint32_t) floor (beats_in_ms / prev_m->divisions_per_bar());
1647         const uint32_t total_bars = bars_in_ms + (prev_m->bbt().bars - 1);
1648         const double remaining_beats = beats_in_ms - (bars_in_ms * prev_m->divisions_per_bar());
1649         const double remaining_ticks = (remaining_beats - floor (remaining_beats)) * BBT_Time::ticks_per_beat;
1650
1651         BBT_Time ret;
1652
1653         ret.ticks = (uint32_t) floor (remaining_ticks + 0.5);
1654         ret.beats = (uint32_t) floor (remaining_beats);
1655         ret.bars = total_bars;
1656
1657         /* 0 0 0 to 1 1 0 - based mapping*/
1658         ++ret.bars;
1659         ++ret.beats;
1660
1661         if (ret.ticks >= BBT_Time::ticks_per_beat) {
1662                 ++ret.beats;
1663                 ret.ticks -= BBT_Time::ticks_per_beat;
1664         }
1665
1666         if (ret.beats >= prev_m->divisions_per_bar() + 1) {
1667                 ++ret.bars;
1668                 ret.beats = 1;
1669         }
1670
1671         return ret;
1672 }
1673
1674 double
1675 TempoMap::pulse_at_bbt (const Timecode::BBT_Time& bbt)
1676 {
1677         Glib::Threads::RWLock::ReaderLock lm (lock);
1678
1679         return pulse_at_bbt_locked (_metrics, bbt);
1680 }
1681
1682 double
1683 TempoMap::pulse_at_bbt_locked (const Metrics& metrics, const Timecode::BBT_Time& bbt) const
1684 {
1685         /* CALLER HOLDS READ LOCK */
1686
1687         MeterSection* prev_m = 0;
1688
1689         /* because audio-locked meters have 'fake' integral beats,
1690            there is no pulse offset here.
1691         */
1692         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1693                 MeterSection* m;
1694                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1695                         if (prev_m) {
1696                                 if (m->bbt().bars > bbt.bars) {
1697                                         break;
1698                                 }
1699                         }
1700                         prev_m = m;
1701                 }
1702         }
1703
1704         const double remaining_bars = bbt.bars - prev_m->bbt().bars;
1705         const double remaining_pulses = remaining_bars * prev_m->divisions_per_bar() / prev_m->note_divisor();
1706         const double ret = remaining_pulses + prev_m->pulse();
1707
1708         return ret;
1709 }
1710
1711 Timecode::BBT_Time
1712 TempoMap::bbt_at_pulse (const double& pulse)
1713 {
1714         Glib::Threads::RWLock::ReaderLock lm (lock);
1715
1716         return bbt_at_pulse_locked (_metrics, pulse);
1717 }
1718
1719 Timecode::BBT_Time
1720 TempoMap::bbt_at_pulse_locked (const Metrics& metrics, const double& pulse) const
1721 {
1722         MeterSection* prev_m = 0;
1723
1724         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1725                 MeterSection* m = 0;
1726
1727                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1728
1729                         if (prev_m) {
1730                                 double const pulses_to_m = m->pulse() - prev_m->pulse();
1731                                 if (prev_m->pulse() + pulses_to_m > pulse) {
1732                                         /* this is the meter after the one our beat is on*/
1733                                         break;
1734                                 }
1735                         }
1736
1737                         prev_m = m;
1738                 }
1739         }
1740
1741         const double beats_in_ms = (pulse - prev_m->pulse()) * prev_m->note_divisor();
1742         const uint32_t bars_in_ms = (uint32_t) floor (beats_in_ms / prev_m->divisions_per_bar());
1743         const uint32_t total_bars = bars_in_ms + (prev_m->bbt().bars - 1);
1744         const double remaining_beats = beats_in_ms - (bars_in_ms * prev_m->divisions_per_bar());
1745         const double remaining_ticks = (remaining_beats - floor (remaining_beats)) * BBT_Time::ticks_per_beat;
1746
1747         BBT_Time ret;
1748
1749         ret.ticks = (uint32_t) floor (remaining_ticks + 0.5);
1750         ret.beats = (uint32_t) floor (remaining_beats);
1751         ret.bars = total_bars;
1752
1753         /* 0 0 0 to 1 1 0 mapping*/
1754         ++ret.bars;
1755         ++ret.beats;
1756
1757         if (ret.ticks >= BBT_Time::ticks_per_beat) {
1758                 ++ret.beats;
1759                 ret.ticks -= BBT_Time::ticks_per_beat;
1760         }
1761
1762         if (ret.beats >= prev_m->divisions_per_bar() + 1) {
1763                 ++ret.bars;
1764                 ret.beats = 1;
1765         }
1766
1767         return ret;
1768 }
1769
1770 void
1771 TempoMap::bbt_time (framepos_t frame, BBT_Time& bbt)
1772 {
1773
1774         if (frame < 0) {
1775                 bbt.bars = 1;
1776                 bbt.beats = 1;
1777                 bbt.ticks = 0;
1778                 warning << string_compose (_("tempo map asked for BBT time at frame %1\n"), frame) << endmsg;
1779                 return;
1780         }
1781         Glib::Threads::RWLock::ReaderLock lm (lock);
1782         const double beat = beat_at_frame_locked (_metrics, frame);
1783
1784         bbt = bbt_at_beat_locked (_metrics, beat);
1785 }
1786
1787 framepos_t
1788 TempoMap::frame_time (const BBT_Time& bbt)
1789 {
1790         if (bbt.bars < 1) {
1791                 warning << string_compose (_("tempo map asked for frame time at bar < 1  (%1)\n"), bbt) << endmsg;
1792                 return 0;
1793         }
1794
1795         if (bbt.beats < 1) {
1796                 throw std::logic_error ("beats are counted from one");
1797         }
1798         Glib::Threads::RWLock::ReaderLock lm (lock);
1799
1800         return frame_time_locked (_metrics, bbt);
1801 }
1802
1803 /* meter section based */
1804 framepos_t
1805 TempoMap::frame_time_locked (const Metrics& metrics, const BBT_Time& bbt) const
1806 {
1807         /* HOLD THE READER LOCK */
1808
1809         const framepos_t ret = frame_at_beat_locked (metrics, beat_at_bbt_locked (metrics, bbt));
1810         return ret;
1811 }
1812
1813 bool
1814 TempoMap::check_solved (const Metrics& metrics) const
1815 {
1816         TempoSection* prev_t = 0;
1817         MeterSection* prev_m = 0;
1818
1819         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1820                 TempoSection* t;
1821                 MeterSection* m;
1822                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1823                         if (!t->active()) {
1824                                 continue;
1825                         }
1826                         if (prev_t) {
1827                                 if ((t->frame() <= prev_t->frame()) || (t->pulse() <= prev_t->pulse())) {
1828                                         return false;
1829                                 }
1830
1831                                 /* precision check ensures pulses and frames align.*/
1832                                 if (t->frame() != prev_t->frame_at_pulse (t->pulse(), _frame_rate)) {
1833                                         if (!t->locked_to_meter()) {
1834                                                 return false;
1835                                         }
1836                                 }
1837                         }
1838                         prev_t = t;
1839                 }
1840
1841                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1842                         if (prev_m && m->position_lock_style() == AudioTime) {
1843                                 TempoSection* t = const_cast<TempoSection*>(&tempo_section_at_locked (metrics, m->frame() - 1));
1844                                 const double nascent_m_pulse = ((m->beat() - prev_m->beat()) / prev_m->note_divisor()) + prev_m->pulse();
1845                                 const framepos_t nascent_m_frame = t->frame_at_pulse (nascent_m_pulse, _frame_rate);
1846
1847                                 if (t && (nascent_m_frame > m->frame() || nascent_m_frame < 0)) {
1848                                         return false;
1849                                 }
1850                         }
1851
1852                         prev_m = m;
1853                 }
1854
1855         }
1856
1857         return true;
1858 }
1859
1860 bool
1861 TempoMap::set_active_tempos (const Metrics& metrics, const framepos_t& frame)
1862 {
1863         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1864                 TempoSection* t;
1865                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1866                         if (!t->movable()) {
1867                                 t->set_active (true);
1868                                 continue;
1869                         }
1870                         if (t->movable() && t->active () && t->position_lock_style() == AudioTime && t->frame() < frame) {
1871                                 t->set_active (false);
1872                                 t->set_pulse (0.0);
1873                         } else if (t->movable() && t->position_lock_style() == AudioTime && t->frame() > frame) {
1874                                 t->set_active (true);
1875                         } else if (t->movable() && t->position_lock_style() == AudioTime && t->frame() == frame) {
1876                                 return false;
1877                         }
1878                 }
1879         }
1880         return true;
1881 }
1882
1883 bool
1884 TempoMap::solve_map_frame (Metrics& imaginary, TempoSection* section, const framepos_t& frame)
1885 {
1886         TempoSection* prev_t = 0;
1887         TempoSection* section_prev = 0;
1888         framepos_t first_m_frame = 0;
1889
1890         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
1891                 MeterSection* m;
1892                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1893                         if (!m->movable()) {
1894                                 first_m_frame = m->frame();
1895                                 break;
1896                         }
1897                 }
1898         }
1899         if (section->movable() && frame <= first_m_frame) {
1900                 return false;
1901         }
1902
1903         section->set_active (true);
1904         section->set_frame (frame);
1905
1906         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
1907                 TempoSection* t;
1908                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1909
1910                         if (!t->active()) {
1911                                 continue;
1912                         }
1913                         if (prev_t) {
1914                                 if (t == section) {
1915                                         section_prev = prev_t;
1916                                         continue;
1917                                 }
1918                                 if (t->position_lock_style() == MusicTime) {
1919                                         prev_t->set_c_func (prev_t->compute_c_func_pulse (t->pulses_per_minute(), t->pulse(), _frame_rate));
1920                                         t->set_frame (prev_t->frame_at_pulse (t->pulse(), _frame_rate));
1921                                 } else {
1922                                         prev_t->set_c_func (prev_t->compute_c_func_frame (t->pulses_per_minute(), t->frame(), _frame_rate));
1923                                         if (!t->locked_to_meter()) {
1924                                                 t->set_pulse (prev_t->pulse_at_frame (t->frame(), _frame_rate));
1925                                         }
1926                                 }
1927                         }
1928                         prev_t = t;
1929                 }
1930         }
1931
1932         if (section_prev) {
1933                 section_prev->set_c_func (section_prev->compute_c_func_frame (section->pulses_per_minute(), frame, _frame_rate));
1934                 if (!section->locked_to_meter()) {
1935                         section->set_pulse (section_prev->pulse_at_frame (frame, _frame_rate));
1936                 }
1937         }
1938
1939         recompute_tempos (imaginary);
1940
1941         if (check_solved (imaginary)) {
1942                 return true;
1943         }
1944
1945         MetricSectionFrameSorter fcmp;
1946         imaginary.sort (fcmp);
1947
1948         recompute_tempos (imaginary);
1949
1950         if (check_solved (imaginary)) {
1951                 return true;
1952         }
1953
1954         return false;
1955 }
1956
1957 bool
1958 TempoMap::solve_map_pulse (Metrics& imaginary, TempoSection* section, const double& pulse)
1959 {
1960         TempoSection* prev_t = 0;
1961         TempoSection* section_prev = 0;
1962
1963         section->set_pulse (pulse);
1964
1965         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
1966                 TempoSection* t;
1967                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1968                         if (!t->active()) {
1969                                 continue;
1970                         }
1971                         if (!t->movable()) {
1972                                 t->set_pulse (0.0);
1973                                 prev_t = t;
1974                                 continue;
1975                         }
1976                         if (prev_t) {
1977                                 if (t == section) {
1978                                         section_prev = prev_t;
1979                                         continue;
1980                                 }
1981                                 if (t->position_lock_style() == MusicTime) {
1982                                         prev_t->set_c_func (prev_t->compute_c_func_pulse (t->pulses_per_minute(), t->pulse(), _frame_rate));
1983                                         t->set_frame (prev_t->frame_at_pulse (t->pulse(), _frame_rate));
1984                                 } else {
1985                                         prev_t->set_c_func (prev_t->compute_c_func_frame (t->pulses_per_minute(), t->frame(), _frame_rate));
1986                                         if (!t->locked_to_meter()) {
1987                                                 t->set_pulse (prev_t->pulse_at_frame (t->frame(), _frame_rate));
1988                                         }
1989                                 }
1990                         }
1991                         prev_t = t;
1992                 }
1993         }
1994
1995         if (section_prev) {
1996                 section_prev->set_c_func (section_prev->compute_c_func_pulse (section->pulses_per_minute(), pulse, _frame_rate));
1997                 section->set_frame (section_prev->frame_at_pulse (pulse, _frame_rate));
1998         }
1999
2000         recompute_tempos (imaginary);
2001
2002         if (check_solved (imaginary)) {
2003                 return true;
2004         }
2005
2006         MetricSectionSorter cmp;
2007         imaginary.sort (cmp);
2008
2009         recompute_tempos (imaginary);
2010         /* Reordering
2011          * XX need a restriction here, but only for this case,
2012          * as audio locked tempos don't interact in the same way.
2013          *
2014          * With music-locked tempos, the solution to cross-dragging can fly off the screen
2015          * e.g.
2016          * |50 bpm                        |250 bpm |60 bpm
2017          *                drag 250 to the pulse after 60->
2018          * a clue: dragging the second 60 <- past the 250 would cause no such problem.
2019          */
2020         if (check_solved (imaginary)) {
2021                 return true;
2022         }
2023
2024         return false;
2025 }
2026
2027 bool
2028 TempoMap::solve_map_frame (Metrics& imaginary, MeterSection* section, const framepos_t& frame)
2029 {
2030         /* disallow moving first meter past any subsequent one, and any movable meter before the first one */
2031         const MeterSection* other =  &meter_section_at_locked (imaginary, frame);
2032         if ((!section->movable() && other->movable()) || (!other->movable() && section->movable() && other->frame() >= frame)) {
2033                 return false;
2034         }
2035
2036         if (!section->movable()) {
2037                 /* lock the first tempo to our first meter */
2038                 if (!set_active_tempos (imaginary, frame)) {
2039                         return false;
2040                 }
2041         }
2042
2043         /* it would make sense to bail out if there is no audio-locked meter,
2044            however it may be desirable to move a music-locked meter by frame at some point.
2045         */
2046         TempoSection* meter_locked_tempo = 0;
2047         for (Metrics::const_iterator ii = imaginary.begin(); ii != imaginary.end(); ++ii) {
2048                 TempoSection* t;
2049                 if ((t = dynamic_cast<TempoSection*> (*ii)) != 0) {
2050                         if ((t->locked_to_meter() || !t->movable()) && t->frame() == section->frame()) {
2051                                 meter_locked_tempo = t;
2052                                 break;
2053                         }
2054                 }
2055         }
2056
2057         if (!meter_locked_tempo) {
2058                 return false;
2059         }
2060
2061         MeterSection* prev_m = 0;
2062         Metrics future_map;
2063         TempoSection* tempo_copy = copy_metrics_and_point (imaginary, future_map, meter_locked_tempo);
2064         bool solved = false;
2065
2066         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2067                 MeterSection* m;
2068                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2069                         if (m == section){
2070                                 if (prev_m && section->movable()) {
2071                                         const double beats = (pulse_at_frame_locked (imaginary, frame) - prev_m->pulse()) * prev_m->note_divisor();
2072                                         if (beats + prev_m->beat() < section->beat()) {
2073                                                 /* set the frame/pulse corresponding to its musical position,
2074                                                  * as an earlier time than this has been requested.
2075                                                 */
2076                                                 const double new_pulse = ((section->beat() - prev_m->beat())
2077                                                                           / prev_m->note_divisor()) + prev_m->pulse();
2078
2079                                                 const framepos_t smallest_frame = frame_at_pulse_locked (future_map, new_pulse);
2080
2081                                                 if ((solved = solve_map_frame (future_map, tempo_copy, smallest_frame))) {
2082                                                         meter_locked_tempo->set_pulse (new_pulse);
2083                                                         solve_map_frame (imaginary, meter_locked_tempo, smallest_frame);
2084                                                         section->set_frame (smallest_frame);
2085                                                         section->set_pulse (new_pulse);
2086                                                 } else {
2087                                                         solved = false;
2088                                                 }
2089
2090                                                 Metrics::const_iterator d = future_map.begin();
2091                                                 while (d != future_map.end()) {
2092                                                         delete (*d);
2093                                                         ++d;
2094                                                 }
2095
2096                                                 if (!solved) {
2097                                                         return false;
2098                                                 }
2099                                         } else {
2100                                                 /* all is ok. set section's tempo */
2101                                                 MeterSection* meter_copy = const_cast<MeterSection*> (&meter_section_at_locked (future_map, section->frame()));
2102                                                 meter_copy->set_frame (frame);
2103
2104                                                 if ((solved = solve_map_frame (future_map, tempo_copy, frame))) {
2105                                                         section->set_frame (frame);
2106                                                         meter_locked_tempo->set_pulse (((section->beat() - prev_m->beat())
2107                                                                                                 / prev_m->note_divisor()) + prev_m->pulse());
2108                                                         solve_map_frame (imaginary, meter_locked_tempo, frame);
2109                                                 } else {
2110                                                         solved = false;
2111                                                 }
2112
2113                                                 Metrics::const_iterator d = future_map.begin();
2114                                                 while (d != future_map.end()) {
2115                                                         delete (*d);
2116                                                         ++d;
2117                                                 }
2118
2119                                                 if (!solved) {
2120                                                         return false;
2121                                                 }
2122                                         }
2123                                 } else {
2124                                         /* not movable (first meter atm) */
2125
2126                                         tempo_copy->set_frame (frame);
2127                                         tempo_copy->set_pulse (0.0);
2128
2129                                         if ((solved = solve_map_frame (future_map, tempo_copy, frame))) {
2130                                                 section->set_frame (frame);
2131                                                 meter_locked_tempo->set_frame (frame);
2132                                                 meter_locked_tempo->set_pulse (0.0);
2133                                                 solve_map_frame (imaginary, meter_locked_tempo, frame);
2134                                         } else {
2135                                                 solved = false;
2136                                         }
2137
2138                                         Metrics::const_iterator d = future_map.begin();
2139                                         while (d != future_map.end()) {
2140                                                 delete (*d);
2141                                                 ++d;
2142                                         }
2143
2144                                         if (!solved) {
2145                                                 return false;
2146                                         }
2147
2148                                         pair<double, BBT_Time> b_bbt = make_pair (0.0, BBT_Time (1, 1, 0));
2149                                         section->set_beat (b_bbt);
2150                                         section->set_pulse (0.0);
2151
2152                                 }
2153                                 break;
2154                         }
2155
2156                         prev_m = m;
2157                 }
2158         }
2159
2160         MetricSectionFrameSorter fcmp;
2161         imaginary.sort (fcmp);
2162
2163         recompute_meters (imaginary);
2164
2165         return true;
2166 }
2167
2168 bool
2169 TempoMap::solve_map_bbt (Metrics& imaginary, MeterSection* section, const BBT_Time& when)
2170 {
2171         /* disallow setting section to an existing meter's bbt */
2172         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2173                 MeterSection* m;
2174                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2175                         if (m != section && m->bbt().bars == when.bars) {
2176                                 return false;
2177                         }
2178                 }
2179         }
2180
2181         MeterSection* prev_m = 0;
2182         MeterSection* section_prev = 0;
2183
2184         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2185                 MeterSection* m;
2186                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2187                         pair<double, BBT_Time> b_bbt;
2188                         double new_pulse = 0.0;
2189
2190                         if (prev_m && m->bbt().bars > when.bars && !section_prev){
2191                                 section_prev = prev_m;
2192                                 const double beats = (when.bars - section_prev->bbt().bars) * section_prev->divisions_per_bar();
2193                                 const double pulse = (beats / section_prev->note_divisor()) + section_prev->pulse();
2194                                 pair<double, BBT_Time> b_bbt = make_pair (beats + section_prev->beat(), when);
2195
2196                                 section->set_beat (b_bbt);
2197                                 section->set_pulse (pulse);
2198                                 section->set_frame (frame_at_pulse_locked (imaginary, pulse));
2199                                 prev_m = section;
2200                                 continue;
2201                         }
2202
2203                         if (m->position_lock_style() == AudioTime) {
2204                                 TempoSection* meter_locked_tempo = 0;
2205
2206                                 for (Metrics::const_iterator ii = imaginary.begin(); ii != imaginary.end(); ++ii) {
2207                                         TempoSection* t;
2208                                         if ((t = dynamic_cast<TempoSection*> (*ii)) != 0) {
2209                                                 if ((t->locked_to_meter() || !t->movable()) && t->frame() == m->frame()) {
2210                                                         meter_locked_tempo = t;
2211                                                         break;
2212                                                 }
2213                                         }
2214                                 }
2215
2216                                 if (!meter_locked_tempo) {
2217                                         return false;
2218                                 }
2219
2220                                 if (prev_m) {
2221                                         const double beats = ((m->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar());
2222
2223                                         if (beats + prev_m->beat() != m->beat()) {
2224                                                 /* tempo/ meter change caused a change in beat (bar). */
2225                                                 b_bbt = make_pair (beats + prev_m->beat()
2226                                                                    , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
2227                                                 new_pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
2228                                         } else if (m->movable()) {
2229                                                 b_bbt = make_pair (m->beat(), m->bbt());
2230                                                 new_pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
2231                                         }
2232                                 } else {
2233                                         b_bbt = make_pair (0.0, BBT_Time (1, 1, 0));
2234                                 }
2235
2236                                 meter_locked_tempo->set_pulse (new_pulse);
2237                                 m->set_beat (b_bbt);
2238                                 m->set_pulse (new_pulse);
2239
2240                         } else {
2241                                 /* MusicTime */
2242                                 const double beats = ((m->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar());
2243                                 if (beats + prev_m->beat() != m->beat()) {
2244                                         /* tempo/ meter change caused a change in beat (bar). */
2245                                         b_bbt = make_pair (beats + prev_m->beat()
2246                                                            , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
2247                                 } else {
2248                                         b_bbt = make_pair (beats + prev_m->beat()
2249                                                            , m->bbt());
2250                                 }
2251                                 new_pulse = (beats / prev_m->note_divisor()) + prev_m->pulse();
2252                                 m->set_beat (b_bbt);
2253                                 m->set_pulse (new_pulse);
2254                                 m->set_frame (frame_at_pulse_locked (imaginary, new_pulse));
2255                         }
2256
2257                         prev_m = m;
2258                 }
2259         }
2260
2261         if (!section_prev) {
2262
2263                 const double beats = (when.bars - prev_m->bbt().bars) * prev_m->divisions_per_bar();
2264                 const double pulse = (beats / prev_m->note_divisor()) + prev_m->pulse();
2265                 pair<double, BBT_Time> b_bbt = make_pair (beats + prev_m->beat(), when);
2266
2267                 section->set_beat (b_bbt);
2268                 section->set_pulse (pulse);
2269                 section->set_frame (frame_at_pulse_locked (imaginary, pulse));
2270         }
2271
2272         MetricSectionSorter cmp;
2273         imaginary.sort (cmp);
2274
2275         recompute_meters (imaginary);
2276
2277         return true;
2278 }
2279
2280 /** places a copy of _metrics into copy and returns a pointer
2281  *  to section's equivalent in copy.
2282  */
2283 TempoSection*
2284 TempoMap::copy_metrics_and_point (const Metrics& metrics, Metrics& copy, TempoSection* section)
2285 {
2286         TempoSection* ret = 0;
2287
2288         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2289                 TempoSection* t;
2290                 MeterSection* m;
2291                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2292                         if (t == section) {
2293                                 ret = new TempoSection (*t);
2294                                 copy.push_back (ret);
2295                                 continue;
2296                         }
2297
2298                         TempoSection* cp = new TempoSection (*t);
2299                         copy.push_back (cp);
2300                 }
2301                 if ((m = dynamic_cast<MeterSection *> (*i)) != 0) {
2302                         MeterSection* cp = new MeterSection (*m);
2303                         copy.push_back (cp);
2304                 }
2305         }
2306
2307         return ret;
2308 }
2309
2310 MeterSection*
2311 TempoMap::copy_metrics_and_point (const Metrics& metrics, Metrics& copy, MeterSection* section)
2312 {
2313         MeterSection* ret = 0;
2314
2315         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2316                 TempoSection* t;
2317                 MeterSection* m;
2318                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2319                         TempoSection* cp = new TempoSection (*t);
2320                         copy.push_back (cp);
2321                 }
2322
2323                 if ((m = dynamic_cast<MeterSection *> (*i)) != 0) {
2324                         if (m == section) {
2325                                 ret = new MeterSection (*m);
2326                                 copy.push_back (ret);
2327                                 continue;
2328                         }
2329                         MeterSection* cp = new MeterSection (*m);
2330                         copy.push_back (cp);
2331                 }
2332         }
2333
2334         return ret;
2335 }
2336
2337 bool
2338 TempoMap::can_solve_bbt (TempoSection* ts, const BBT_Time& bbt)
2339 {
2340         Metrics copy;
2341         TempoSection* tempo_copy = 0;
2342
2343         {
2344                 Glib::Threads::RWLock::ReaderLock lm (lock);
2345                 tempo_copy = copy_metrics_and_point (_metrics, copy, ts);
2346                 if (!tempo_copy) {
2347                         return false;
2348                 }
2349         }
2350
2351         const bool ret = solve_map_pulse (copy, tempo_copy, pulse_at_bbt_locked (copy, bbt));
2352
2353         Metrics::const_iterator d = copy.begin();
2354         while (d != copy.end()) {
2355                 delete (*d);
2356                 ++d;
2357         }
2358
2359         return ret;
2360 }
2361
2362 /**
2363 * This is for a gui that needs to know the pulse or frame of a tempo section if it were to be moved to some bbt time,
2364 * taking any possible reordering as a consequence of this into account.
2365 * @param section - the section to be altered
2366 * @param bbt - the bbt where the altered tempo will fall
2367 * @return returns - the position in pulses and frames (as a pair) where the new tempo section will lie.
2368 */
2369 pair<double, framepos_t>
2370 TempoMap::predict_tempo_position (TempoSection* section, const BBT_Time& bbt)
2371 {
2372         Metrics future_map;
2373         pair<double, framepos_t> ret = make_pair (0.0, 0);
2374
2375         Glib::Threads::RWLock::ReaderLock lm (lock);
2376
2377         TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, section);
2378
2379         const double beat = beat_at_bbt_locked (future_map, bbt);
2380
2381         if (solve_map_pulse (future_map, tempo_copy, pulse_at_beat_locked (future_map, beat))) {
2382                 ret.first = tempo_copy->pulse();
2383                 ret.second = tempo_copy->frame();
2384         } else {
2385                 ret.first = section->pulse();
2386                 ret.second = section->frame();
2387         }
2388
2389         Metrics::const_iterator d = future_map.begin();
2390         while (d != future_map.end()) {
2391                 delete (*d);
2392                 ++d;
2393         }
2394         return ret;
2395 }
2396
2397 void
2398 TempoMap::gui_move_tempo (TempoSection* ts, const framepos_t& frame)
2399 {
2400         Metrics future_map;
2401
2402         if (ts->position_lock_style() == MusicTime) {
2403                 {
2404                         Glib::Threads::RWLock::WriterLock lm (lock);
2405                         TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, ts);
2406                         const double pulse = pulse_at_frame_locked (future_map, frame);
2407                         if (solve_map_pulse (future_map, tempo_copy, pulse)) {
2408                                 solve_map_pulse (_metrics, ts, pulse);
2409                                 recompute_meters (_metrics);
2410                         }
2411                 }
2412
2413         } else {
2414
2415                 {
2416                         Glib::Threads::RWLock::WriterLock lm (lock);
2417                         TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, ts);
2418                         if (solve_map_frame (future_map, tempo_copy, frame)) {
2419                                 solve_map_frame (_metrics, ts, frame);
2420                                 recompute_meters (_metrics);
2421                         }
2422                 }
2423         }
2424
2425         Metrics::const_iterator d = future_map.begin();
2426         while (d != future_map.end()) {
2427                 delete (*d);
2428                 ++d;
2429         }
2430
2431         MetricPositionChanged (); // Emit Signal
2432 }
2433
2434 void
2435 TempoMap::gui_move_meter (MeterSection* ms, const framepos_t& frame)
2436 {
2437         Metrics future_map;
2438
2439         if (ms->position_lock_style() == AudioTime) {
2440
2441                 {
2442                         Glib::Threads::RWLock::WriterLock lm (lock);
2443                         MeterSection* copy = copy_metrics_and_point (_metrics, future_map, ms);
2444
2445                         if (solve_map_frame (future_map, copy, frame)) {
2446                                 solve_map_frame (_metrics, ms, frame);
2447                                 recompute_tempos (_metrics);
2448                         }
2449                 }
2450         } else {
2451                 {
2452                         Glib::Threads::RWLock::WriterLock lm (lock);
2453                         MeterSection* copy = copy_metrics_and_point (_metrics, future_map, ms);
2454
2455                         const double beat = beat_at_frame_locked (_metrics, frame);
2456                         const Timecode::BBT_Time bbt = bbt_at_beat_locked (_metrics, beat);
2457
2458                         if (solve_map_bbt (future_map, copy, bbt)) {
2459                                 solve_map_bbt (_metrics, ms, bbt);
2460                                 recompute_tempos (_metrics);
2461                         }
2462                 }
2463         }
2464
2465         Metrics::const_iterator d = future_map.begin();
2466         while (d != future_map.end()) {
2467                 delete (*d);
2468                 ++d;
2469         }
2470
2471         MetricPositionChanged (); // Emit Signal
2472 }
2473
2474 bool
2475 TempoMap::gui_change_tempo (TempoSection* ts, const Tempo& bpm)
2476 {
2477         Metrics future_map;
2478         bool can_solve = false;
2479         {
2480                 Glib::Threads::RWLock::WriterLock lm (lock);
2481                 TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, ts);
2482                 tempo_copy->set_beats_per_minute (bpm.beats_per_minute());
2483                 recompute_tempos (future_map);
2484
2485                 if (check_solved (future_map)) {
2486                         ts->set_beats_per_minute (bpm.beats_per_minute());
2487                         recompute_map (_metrics);
2488                         can_solve = true;
2489                 }
2490         }
2491
2492         Metrics::const_iterator d = future_map.begin();
2493         while (d != future_map.end()) {
2494                 delete (*d);
2495                 ++d;
2496         }
2497         if (can_solve) {
2498                 MetricPositionChanged (); // Emit Signal
2499         }
2500         return can_solve;
2501 }
2502
2503 void
2504 TempoMap::gui_dilate_tempo (TempoSection* ts, const framepos_t& frame, const framepos_t& end_frame, const double& pulse)
2505 {
2506         /*
2507           Ts (future prev_t)   Tnext
2508           |                    |
2509           |     [drag^]        |
2510           |----------|----------
2511                 e_f  pulse(frame)
2512         */
2513
2514         Metrics future_map;
2515
2516         {
2517                 Glib::Threads::RWLock::WriterLock lm (lock);
2518
2519                 if (!ts) {
2520                         return;
2521                 }
2522
2523                 TempoSection* prev_t = copy_metrics_and_point (_metrics, future_map, ts);
2524                 TempoSection* prev_to_prev_t = 0;
2525                 const frameoffset_t fr_off = end_frame - frame;
2526
2527                 if (prev_t && prev_t->pulse() > 0.0) {
2528                         prev_to_prev_t = const_cast<TempoSection*>(&tempo_section_at_locked (future_map, prev_t->frame() - 1));
2529                 }
2530
2531                 TempoSection* next_t = 0;
2532                 for (Metrics::iterator i = future_map.begin(); i != future_map.end(); ++i) {
2533                         TempoSection* t = 0;
2534                         if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2535                                 if (t->frame() > ts->frame()) {
2536                                         next_t = t;
2537                                         break;
2538                                 }
2539                         }
2540                 }
2541
2542                 /* the change in frames is the result of changing the slope of at most 2 previous tempo sections.
2543                    constant to constant is straightforward, as the tempo prev to prev_t has constant slope.
2544                 */
2545                 double contribution = 0.0;
2546                 double start_pulse = prev_t->pulse_at_frame (frame, _frame_rate);
2547
2548                 if (next_t && prev_to_prev_t && prev_to_prev_t->type() == TempoSection::Ramp) {
2549                         contribution = (prev_t->frame() - prev_to_prev_t->frame()) / (double) (next_t->frame() - prev_to_prev_t->frame());
2550                 }
2551
2552                 frameoffset_t prev_t_frame_contribution = fr_off - (contribution * (double) fr_off);
2553                 double end_pulse = prev_t->pulse_at_frame (end_frame, _frame_rate);
2554                 double new_bpm;
2555
2556                 if (prev_t->type() == TempoSection::Constant || prev_t->c_func() == 0.0) {
2557
2558                         if (prev_t->position_lock_style() == MusicTime) {
2559                                 if (prev_to_prev_t && prev_to_prev_t->type() == TempoSection::Ramp) {
2560
2561                                         new_bpm = prev_t->beats_per_minute() * ((frame - prev_to_prev_t->frame())
2562                                                                                 / (double) ((frame + prev_t_frame_contribution) - prev_to_prev_t->frame()));
2563
2564                                 } else {
2565                                         /* prev to prev is irrelevant */
2566
2567                                         if (start_pulse != prev_t->pulse()) {
2568                                                 new_bpm = prev_t->beats_per_minute() * ((start_pulse - prev_t->pulse()) / (end_pulse - prev_t->pulse()));
2569                                         } else {
2570                                                 new_bpm = prev_t->beats_per_minute();
2571                                         }
2572                                 }
2573                         } else {
2574                                 /* AudioTime */
2575                                 if (prev_to_prev_t && prev_to_prev_t->type() == TempoSection::Ramp) {
2576                                         new_bpm = prev_t->beats_per_minute() * ((frame - prev_t->frame())
2577                                                                                 / (double) ((frame + prev_t_frame_contribution) - prev_t->frame()));
2578                                 } else {
2579                                         /* prev_to_prev_t is irrelevant */
2580
2581                                         if (end_frame != prev_t->frame()) {
2582                                                 new_bpm = prev_t->beats_per_minute() * ((frame - prev_t->frame()) / (double) (end_frame - prev_t->frame()));
2583                                         } else {
2584                                                 new_bpm = prev_t->beats_per_minute();
2585                                         }
2586                                 }
2587                         }
2588                 } else {
2589
2590                         double frame_ratio;
2591                         double pulse_ratio;
2592                         const framepos_t pulse_pos = prev_t->frame_at_pulse (pulse, _frame_rate);
2593
2594                         if (prev_to_prev_t) {
2595
2596                                 frame_ratio = (((pulse_pos - fr_off) - prev_to_prev_t->frame()) / (double) ((pulse_pos) - prev_to_prev_t->frame()));
2597                                 pulse_ratio = ((start_pulse - prev_to_prev_t->pulse()) / (end_pulse - prev_to_prev_t->pulse()));
2598                         } else {
2599
2600                                 frame_ratio = (((pulse_pos - fr_off) - prev_t->frame()) / (double) ((pulse_pos) - prev_t->frame()));
2601                                 pulse_ratio = (start_pulse / end_pulse);
2602                         }
2603                         new_bpm = prev_t->beats_per_minute() * (pulse_ratio * frame_ratio);
2604                 }
2605
2606                 prev_t->set_beats_per_minute (new_bpm);
2607                 recompute_tempos (future_map);
2608                 recompute_meters (future_map);
2609
2610                 if (check_solved (future_map)) {
2611                         ts->set_beats_per_minute (new_bpm);
2612                         recompute_tempos (_metrics);
2613                         recompute_meters (_metrics);
2614                 }
2615         }
2616
2617         Metrics::const_iterator d = future_map.begin();
2618         while (d != future_map.end()) {
2619                 delete (*d);
2620                 ++d;
2621         }
2622
2623         MetricPositionChanged (); // Emit Signal
2624 }
2625
2626 framecnt_t
2627 TempoMap::bbt_duration_at (framepos_t pos, const BBT_Time& bbt, int dir)
2628 {
2629         Glib::Threads::RWLock::ReaderLock lm (lock);
2630
2631         const double tick_at_time = beat_at_frame_locked (_metrics, pos) * BBT_Time::ticks_per_beat;
2632         const double bbt_ticks = bbt.ticks + (bbt.beats * BBT_Time::ticks_per_beat);
2633         const double total_beats = (tick_at_time + bbt_ticks) / BBT_Time::ticks_per_beat;
2634
2635         return frame_at_beat_locked (_metrics, total_beats);
2636 }
2637
2638 framepos_t
2639 TempoMap::round_to_bar (framepos_t fr, RoundMode dir)
2640 {
2641         return round_to_type (fr, dir, Bar);
2642 }
2643
2644 framepos_t
2645 TempoMap::round_to_beat (framepos_t fr, RoundMode dir)
2646 {
2647         return round_to_type (fr, dir, Beat);
2648 }
2649
2650 framepos_t
2651 TempoMap::round_to_beat_subdivision (framepos_t fr, int sub_num, RoundMode dir)
2652 {
2653         Glib::Threads::RWLock::ReaderLock lm (lock);
2654         uint32_t ticks = (uint32_t) floor (beat_at_frame_locked (_metrics, fr) * BBT_Time::ticks_per_beat);
2655         uint32_t beats = (uint32_t) floor (ticks / BBT_Time::ticks_per_beat);
2656         uint32_t ticks_one_subdivisions_worth = (uint32_t) BBT_Time::ticks_per_beat / sub_num;
2657
2658         ticks -= beats * BBT_Time::ticks_per_beat;
2659
2660         if (dir > 0) {
2661                 /* round to next (or same iff dir == RoundUpMaybe) */
2662
2663                 uint32_t mod = ticks % ticks_one_subdivisions_worth;
2664
2665                 if (mod == 0 && dir == RoundUpMaybe) {
2666                         /* right on the subdivision, which is fine, so do nothing */
2667
2668                 } else if (mod == 0) {
2669                         /* right on the subdivision, so the difference is just the subdivision ticks */
2670                         ticks += ticks_one_subdivisions_worth;
2671
2672                 } else {
2673                         /* not on subdivision, compute distance to next subdivision */
2674
2675                         ticks += ticks_one_subdivisions_worth - mod;
2676                 }
2677
2678                 if (ticks >= BBT_Time::ticks_per_beat) {
2679                         ticks -= BBT_Time::ticks_per_beat;
2680                 }
2681         } else if (dir < 0) {
2682
2683                 /* round to previous (or same iff dir == RoundDownMaybe) */
2684
2685                 uint32_t difference = ticks % ticks_one_subdivisions_worth;
2686
2687                 if (difference == 0 && dir == RoundDownAlways) {
2688                         /* right on the subdivision, but force-rounding down,
2689                            so the difference is just the subdivision ticks */
2690                         difference = ticks_one_subdivisions_worth;
2691                 }
2692
2693                 if (ticks < difference) {
2694                         ticks = BBT_Time::ticks_per_beat - ticks;
2695                 } else {
2696                         ticks -= difference;
2697                 }
2698
2699         } else {
2700                 /* round to nearest */
2701                 double rem;
2702
2703                 /* compute the distance to the previous and next subdivision */
2704
2705                 if ((rem = fmod ((double) ticks, (double) ticks_one_subdivisions_worth)) > ticks_one_subdivisions_worth/2.0) {
2706
2707                         /* closer to the next subdivision, so shift forward */
2708
2709                         ticks = lrint (ticks + (ticks_one_subdivisions_worth - rem));
2710
2711                         DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("moved forward to %1\n", ticks));
2712
2713                         if (ticks > BBT_Time::ticks_per_beat) {
2714                                 ++beats;
2715                                 ticks -= BBT_Time::ticks_per_beat;
2716                                 DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("fold beat to %1\n", beats));
2717                         }
2718
2719                 } else if (rem > 0) {
2720
2721                         /* closer to previous subdivision, so shift backward */
2722
2723                         if (rem > ticks) {
2724                                 if (beats == 0) {
2725                                         /* can't go backwards past zero, so ... */
2726                                         return 0;
2727                                 }
2728                                 /* step back to previous beat */
2729                                 --beats;
2730                                 ticks = lrint (BBT_Time::ticks_per_beat - rem);
2731                                 DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("step back beat to %1\n", beats));
2732                         } else {
2733                                 ticks = lrint (ticks - rem);
2734                                 DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("moved backward to %1\n", ticks));
2735                         }
2736                 } else {
2737                         /* on the subdivision, do nothing */
2738                 }
2739         }
2740
2741         const framepos_t ret_frame = frame_at_beat_locked (_metrics, beats + (ticks / BBT_Time::ticks_per_beat));
2742
2743         return ret_frame;
2744 }
2745
2746 framepos_t
2747 TempoMap::round_to_type (framepos_t frame, RoundMode dir, BBTPointType type)
2748 {
2749         Glib::Threads::RWLock::ReaderLock lm (lock);
2750
2751         const double beat_at_framepos = beat_at_frame_locked (_metrics, frame);
2752         BBT_Time bbt (bbt_at_beat_locked (_metrics, beat_at_framepos));
2753
2754         switch (type) {
2755         case Bar:
2756                 if (dir < 0) {
2757                         /* find bar previous to 'frame' */
2758                         bbt.beats = 1;
2759                         bbt.ticks = 0;
2760                         return frame_time_locked (_metrics, bbt);
2761
2762                 } else if (dir > 0) {
2763                         /* find bar following 'frame' */
2764                         ++bbt.bars;
2765                         bbt.beats = 1;
2766                         bbt.ticks = 0;
2767                         return frame_time_locked (_metrics, bbt);
2768                 } else {
2769                         /* true rounding: find nearest bar */
2770                         framepos_t raw_ft = frame_time_locked (_metrics, bbt);
2771                         bbt.beats = 1;
2772                         bbt.ticks = 0;
2773                         framepos_t prev_ft = frame_time_locked (_metrics, bbt);
2774                         ++bbt.bars;
2775                         framepos_t next_ft = frame_time_locked (_metrics, bbt);
2776
2777                         if ((raw_ft - prev_ft) > (next_ft - prev_ft) / 2) {
2778                                 return next_ft;
2779                         } else {
2780                                 return prev_ft;
2781                         }
2782                 }
2783
2784                 break;
2785
2786         case Beat:
2787                 if (dir < 0) {
2788                         return frame_at_beat_locked (_metrics, floor (beat_at_framepos));
2789                 } else if (dir > 0) {
2790                         return frame_at_beat_locked (_metrics, ceil (beat_at_framepos));
2791                 } else {
2792                         return frame_at_beat_locked (_metrics, floor (beat_at_framepos + 0.5));
2793                 }
2794                 break;
2795         }
2796
2797         return 0;
2798 }
2799
2800 void
2801 TempoMap::get_grid (vector<TempoMap::BBTPoint>& points,
2802                     framepos_t lower, framepos_t upper)
2803 {
2804         Glib::Threads::RWLock::ReaderLock lm (lock);
2805         int32_t cnt = ceil (beat_at_frame_locked (_metrics, lower));
2806         framecnt_t pos = 0;
2807         /* although the map handles negative beats, bbt doesn't. */
2808         if (cnt < 0.0) {
2809                 cnt = 0.0;
2810         }
2811         while (pos < upper) {
2812                 pos = frame_at_beat_locked (_metrics, cnt);
2813                 const TempoSection tempo = tempo_section_at_locked (_metrics, pos);
2814                 const MeterSection meter = meter_section_at_locked (_metrics, pos);
2815                 const BBT_Time bbt = bbt_at_beat_locked (_metrics, cnt);
2816                 points.push_back (BBTPoint (meter, tempo_at_locked (_metrics, pos), pos, bbt.bars, bbt.beats, tempo.c_func()));
2817                 ++cnt;
2818         }
2819 }
2820
2821 const TempoSection&
2822 TempoMap::tempo_section_at (framepos_t frame) const
2823 {
2824         Glib::Threads::RWLock::ReaderLock lm (lock);
2825         return tempo_section_at_locked (_metrics, frame);
2826 }
2827
2828 const TempoSection&
2829 TempoMap::tempo_section_at_locked (const Metrics& metrics, framepos_t frame) const
2830 {
2831         Metrics::const_iterator i;
2832         TempoSection* prev = 0;
2833
2834         for (i = metrics.begin(); i != metrics.end(); ++i) {
2835                 TempoSection* t;
2836
2837                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2838                         if (!t->active()) {
2839                                 continue;
2840                         }
2841                         if (prev && t->frame() > frame) {
2842                                 break;
2843                         }
2844
2845                         prev = t;
2846                 }
2847         }
2848
2849         if (prev == 0) {
2850                 fatal << endmsg;
2851                 abort(); /*NOTREACHED*/
2852         }
2853
2854         return *prev;
2855 }
2856
2857 const TempoSection&
2858 TempoMap::tempo_section_at_beat_locked (const Metrics& metrics, const double& beat) const
2859 {
2860         TempoSection* prev_t = 0;
2861         const MeterSection* prev_m = &meter_section_at_beat_locked (metrics, beat);
2862
2863         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2864                 TempoSection* t;
2865                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2866                         if (prev_t && ((t->pulse() - prev_m->pulse()) * prev_m->note_divisor()) + prev_m->beat() > beat) {
2867                                 break;
2868                         }
2869                         prev_t = t;
2870                 }
2871
2872         }
2873         return *prev_t;
2874 }
2875
2876 const TempoSection&
2877 TempoMap::tempo_section_at_pulse_locked (const Metrics& metrics, const double& pulse) const
2878 {
2879         TempoSection* prev_t = 0;
2880
2881         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2882                 TempoSection* t;
2883                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2884                         if (prev_t && t->pulse() > pulse) {
2885                                 break;
2886                         }
2887                         prev_t = t;
2888                 }
2889
2890         }
2891         return *prev_t;
2892 }
2893
2894 /* don't use this to calculate length (the tempo is only correct for this frame).
2895    do that stuff based on the beat_at_frame and frame_at_beat api
2896 */
2897 double
2898 TempoMap::frames_per_beat_at (const framepos_t& frame, const framecnt_t& sr) const
2899 {
2900         Glib::Threads::RWLock::ReaderLock lm (lock);
2901
2902         const TempoSection* ts_at = &tempo_section_at_locked (_metrics, frame);
2903         const TempoSection* ts_after = 0;
2904         Metrics::const_iterator i;
2905
2906         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
2907                 TempoSection* t;
2908
2909                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2910                         if (!t->active()) {
2911                                 continue;
2912                         }
2913                         if ((*i)->frame() > frame) {
2914                                 ts_after = t;
2915                                 break;
2916                         }
2917                 }
2918         }
2919
2920         if (ts_after) {
2921                 return  (60.0 * _frame_rate) / (ts_at->tempo_at_frame (frame, _frame_rate));
2922         }
2923         /* must be treated as constant tempo */
2924         return ts_at->frames_per_beat (_frame_rate);
2925 }
2926
2927 const Tempo
2928 TempoMap::tempo_at_locked (const Metrics& metrics, const framepos_t& frame) const
2929 {
2930         TempoSection* prev_t = 0;
2931
2932         Metrics::const_iterator i;
2933
2934         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
2935                 TempoSection* t;
2936                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2937                         if (!t->active()) {
2938                                 continue;
2939                         }
2940                         if ((prev_t) && t->frame() > frame) {
2941                                 /* t is the section past frame */
2942                                 const double ret_bpm = prev_t->tempo_at_frame (frame, _frame_rate) * prev_t->note_type();
2943                                 const Tempo ret_tempo (ret_bpm, prev_t->note_type());
2944                                 return ret_tempo;
2945                         }
2946                         prev_t = t;
2947                 }
2948         }
2949
2950         const double ret = prev_t->beats_per_minute();
2951         const Tempo ret_tempo (ret, prev_t->note_type ());
2952
2953         return ret_tempo;
2954 }
2955
2956 const Tempo
2957 TempoMap::tempo_at (const framepos_t& frame) const
2958 {
2959         Glib::Threads::RWLock::ReaderLock lm (lock);
2960         return tempo_at_locked (_metrics, frame);
2961 }
2962
2963 const MeterSection&
2964 TempoMap::meter_section_at_locked (const Metrics& metrics, framepos_t frame) const
2965 {
2966         Metrics::const_iterator i;
2967         MeterSection* prev = 0;
2968
2969         for (i = metrics.begin(); i != metrics.end(); ++i) {
2970                 MeterSection* m;
2971
2972                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2973
2974                         if (prev && (*i)->frame() > frame) {
2975                                 break;
2976                         }
2977
2978                         prev = m;
2979                 }
2980         }
2981
2982         if (prev == 0) {
2983                 fatal << endmsg;
2984                 abort(); /*NOTREACHED*/
2985         }
2986
2987         return *prev;
2988 }
2989
2990
2991 const MeterSection&
2992 TempoMap::meter_section_at (framepos_t frame) const
2993 {
2994         Glib::Threads::RWLock::ReaderLock lm (lock);
2995         return meter_section_at_locked (_metrics, frame);
2996 }
2997
2998 const MeterSection&
2999 TempoMap::meter_section_at_beat_locked (const Metrics& metrics, const double& beat) const
3000 {
3001         MeterSection* prev_m = 0;
3002
3003         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
3004                 MeterSection* m;
3005                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
3006                         if (prev_m && m->beat() > beat) {
3007                                 break;
3008                         }
3009                         prev_m = m;
3010                 }
3011
3012         }
3013         return *prev_m;
3014 }
3015
3016 const MeterSection&
3017 TempoMap::meter_section_at_beat (double beat) const
3018 {
3019         Glib::Threads::RWLock::ReaderLock lm (lock);
3020         return meter_section_at_beat_locked (_metrics, beat);
3021 }
3022
3023 const Meter&
3024 TempoMap::meter_at (framepos_t frame) const
3025 {
3026         TempoMetric m (metric_at (frame));
3027         return m.meter();
3028 }
3029
3030 void
3031 TempoMap::fix_legacy_session ()
3032 {
3033         MeterSection* prev_m = 0;
3034         TempoSection* prev_t = 0;
3035
3036         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3037                 MeterSection* m;
3038                 TempoSection* t;
3039
3040                 if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
3041                         if (!m->movable()) {
3042                                 pair<double, BBT_Time> bbt = make_pair (0.0, BBT_Time (1, 1, 0));
3043                                 m->set_beat (bbt);
3044                                 m->set_pulse (0.0);
3045                                 m->set_frame (0);
3046                                 m->set_position_lock_style (AudioTime);
3047                                 prev_m = m;
3048                                 continue;
3049                         }
3050                         if (prev_m) {
3051                                 pair<double, BBT_Time> start = make_pair (((m->bbt().bars - 1) * prev_m->note_divisor())
3052                                                                           + (m->bbt().beats - 1)
3053                                                                           + (m->bbt().ticks / BBT_Time::ticks_per_beat)
3054                                                                           , m->bbt());
3055                                 m->set_beat (start);
3056                                 const double start_beat = ((m->bbt().bars - 1) * prev_m->note_divisor())
3057                                         + (m->bbt().beats - 1)
3058                                         + (m->bbt().ticks / BBT_Time::ticks_per_beat);
3059                                 m->set_pulse (start_beat / prev_m->note_divisor());
3060                         }
3061                         prev_m = m;
3062                 } else if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
3063
3064                         if (!t->active()) {
3065                                 continue;
3066                         }
3067
3068                         if (!t->movable()) {
3069                                 t->set_pulse (0.0);
3070                                 t->set_frame (0);
3071                                 t->set_position_lock_style (AudioTime);
3072                                 prev_t = t;
3073                                 continue;
3074                         }
3075
3076                         if (prev_t) {
3077                                 const double beat = ((t->legacy_bbt().bars - 1) * ((prev_m) ? prev_m->note_divisor() : 4.0))
3078                                         + (t->legacy_bbt().beats - 1)
3079                                         + (t->legacy_bbt().ticks / BBT_Time::ticks_per_beat);
3080                                 if (prev_m) {
3081                                         t->set_pulse (beat / prev_m->note_divisor());
3082                                 } else {
3083                                         /* really shouldn't happen but.. */
3084                                         t->set_pulse (beat / 4.0);
3085                                 }
3086                         }
3087                         prev_t = t;
3088                 }
3089         }
3090 }
3091
3092 XMLNode&
3093 TempoMap::get_state ()
3094 {
3095         Metrics::const_iterator i;
3096         XMLNode *root = new XMLNode ("TempoMap");
3097
3098         {
3099                 Glib::Threads::RWLock::ReaderLock lm (lock);
3100                 for (i = _metrics.begin(); i != _metrics.end(); ++i) {
3101                         root->add_child_nocopy ((*i)->get_state());
3102                 }
3103         }
3104
3105         return *root;
3106 }
3107
3108 int
3109 TempoMap::set_state (const XMLNode& node, int /*version*/)
3110 {
3111         {
3112                 Glib::Threads::RWLock::WriterLock lm (lock);
3113
3114                 XMLNodeList nlist;
3115                 XMLNodeConstIterator niter;
3116                 Metrics old_metrics (_metrics);
3117                 _metrics.clear();
3118
3119                 nlist = node.children();
3120
3121                 for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
3122                         XMLNode* child = *niter;
3123
3124                         if (child->name() == TempoSection::xml_state_node_name) {
3125
3126                                 try {
3127                                         TempoSection* ts = new TempoSection (*child);
3128                                         _metrics.push_back (ts);
3129                                 }
3130
3131                                 catch (failed_constructor& err){
3132                                         error << _("Tempo map: could not set new state, restoring old one.") << endmsg;
3133                                         _metrics = old_metrics;
3134                                         break;
3135                                 }
3136
3137                         } else if (child->name() == MeterSection::xml_state_node_name) {
3138
3139                                 try {
3140                                         MeterSection* ms = new MeterSection (*child);
3141                                         _metrics.push_back (ms);
3142                                 }
3143
3144                                 catch (failed_constructor& err) {
3145                                         error << _("Tempo map: could not set new state, restoring old one.") << endmsg;
3146                                         _metrics = old_metrics;
3147                                         break;
3148                                 }
3149                         }
3150                 }
3151
3152                 if (niter == nlist.end()) {
3153                         MetricSectionSorter cmp;
3154                         _metrics.sort (cmp);
3155                 }
3156
3157                 /* check for legacy sessions where bbt was the base musical unit for tempo */
3158                 for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3159                         TempoSection* t;
3160                         if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
3161                                 if (t->legacy_bbt().bars != 0) {
3162                                         fix_legacy_session();
3163                                         break;
3164                                 }
3165                                 break;
3166                         }
3167                 }
3168
3169                 /* check for multiple tempo/meters at the same location, which
3170                    ardour2 somehow allowed.
3171                 */
3172
3173                 Metrics::iterator prev = _metrics.end();
3174                 for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3175                         if (prev != _metrics.end()) {
3176                                 MeterSection* ms;
3177                                 MeterSection* prev_m;
3178                                 TempoSection* ts;
3179                                 TempoSection* prev_t;
3180                                 if ((prev_m = dynamic_cast<MeterSection*>(*prev)) != 0 && (ms = dynamic_cast<MeterSection*>(*i)) != 0) {
3181                                         if (prev_m->pulse() == ms->pulse()) {
3182                                                 cerr << string_compose (_("Multiple meter definitions found at %1"), prev_m->pulse()) << endmsg;
3183                                                 error << string_compose (_("Multiple meter definitions found at %1"), prev_m->pulse()) << endmsg;
3184                                                 return -1;
3185                                         }
3186                                 } else if ((prev_t = dynamic_cast<TempoSection*>(*prev)) != 0 && (ts = dynamic_cast<TempoSection*>(*i)) != 0) {
3187                                         if (prev_t->pulse() == ts->pulse()) {
3188                                                 cerr << string_compose (_("Multiple tempo definitions found at %1"), prev_t->pulse()) << endmsg;
3189                                                 error << string_compose (_("Multiple tempo definitions found at %1"), prev_t->pulse()) << endmsg;
3190                                                 return -1;
3191                                         }
3192                                 }
3193                         }
3194                         prev = i;
3195                 }
3196
3197                 recompute_map (_metrics);
3198         }
3199
3200         PropertyChanged (PropertyChange ());
3201
3202         return 0;
3203 }
3204
3205 void
3206 TempoMap::dump (const Metrics& metrics, std::ostream& o) const
3207 {
3208         Glib::Threads::RWLock::ReaderLock lm (lock, Glib::Threads::TRY_LOCK);
3209         const MeterSection* m;
3210         const TempoSection* t;
3211         const TempoSection* prev_t = 0;
3212
3213         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
3214
3215                 if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
3216                         o << "Tempo @ " << *i << t->beats_per_minute() << " BPM (pulse = 1/" << t->note_type() << ") at " << t->pulse() << " frame= " << t->frame() << " (movable? "
3217                           << t->movable() << ')' << " pos lock: " << enum_2_string (t->position_lock_style()) << std::endl;
3218                         o << "current      : " << t->beats_per_minute() << " | " << t->pulse() << " | " << t->frame() << std::endl;
3219                         if (prev_t) {
3220                                 o << "previous     : " << prev_t->beats_per_minute() << " | " << prev_t->pulse() << " | " << prev_t->frame() << std::endl;
3221                                 o << "calculated   : " << prev_t->tempo_at_pulse (t->pulse()) *  prev_t->note_type() << " | " << prev_t->pulse_at_tempo (t->pulses_per_minute(), t->frame(), _frame_rate) <<  " | " << prev_t->frame_at_tempo (t->pulses_per_minute(), t->pulse(), _frame_rate) << std::endl;
3222                         }
3223                         prev_t = t;
3224                 } else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
3225                         o << "Meter @ " << *i << ' ' << m->divisions_per_bar() << '/' << m->note_divisor() << " at " << m->bbt() << " frame= " << m->frame()
3226                           << " pulse: " << m->pulse() <<  " beat : " << m->beat() << " pos lock: " << enum_2_string (m->position_lock_style()) << " (movable? " << m->movable() << ')' << endl;
3227                 }
3228         }
3229         o << "------" << std::endl;
3230 }
3231
3232 int
3233 TempoMap::n_tempos() const
3234 {
3235         Glib::Threads::RWLock::ReaderLock lm (lock);
3236         int cnt = 0;
3237
3238         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3239                 if (dynamic_cast<const TempoSection*>(*i) != 0) {
3240                         cnt++;
3241                 }
3242         }
3243
3244         return cnt;
3245 }
3246
3247 int
3248 TempoMap::n_meters() const
3249 {
3250         Glib::Threads::RWLock::ReaderLock lm (lock);
3251         int cnt = 0;
3252
3253         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3254                 if (dynamic_cast<const MeterSection*>(*i) != 0) {
3255                         cnt++;
3256                 }
3257         }
3258
3259         return cnt;
3260 }
3261
3262 void
3263 TempoMap::insert_time (framepos_t where, framecnt_t amount)
3264 {
3265         {
3266                 Glib::Threads::RWLock::WriterLock lm (lock);
3267                 for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3268                         if ((*i)->frame() >= where && (*i)->movable ()) {
3269                                 (*i)->set_frame ((*i)->frame() + amount);
3270                         }
3271                 }
3272
3273                 /* now reset the BBT time of all metrics, based on their new
3274                  * audio time. This is the only place where we do this reverse
3275                  * timestamp.
3276                  */
3277
3278                 Metrics::iterator i;
3279                 const MeterSection* meter;
3280                 const TempoSection* tempo;
3281                 MeterSection *m;
3282                 TempoSection *t;
3283
3284                 meter = &first_meter ();
3285                 tempo = &first_tempo ();
3286
3287                 BBT_Time start;
3288                 BBT_Time end;
3289
3290                 // cerr << "\n###################### TIMESTAMP via AUDIO ##############\n" << endl;
3291
3292                 bool first = true;
3293                 MetricSection* prev = 0;
3294
3295                 for (i = _metrics.begin(); i != _metrics.end(); ++i) {
3296
3297                         BBT_Time bbt;
3298                         //TempoMetric metric (*meter, *tempo);
3299                         MeterSection* ms = const_cast<MeterSection*>(meter);
3300                         TempoSection* ts = const_cast<TempoSection*>(tempo);
3301                         if (prev) {
3302                                 if (ts){
3303                                         if ((t = dynamic_cast<TempoSection*>(prev)) != 0) {
3304                                                 if (!t->active()) {
3305                                                         continue;
3306                                                 }
3307                                                 ts->set_pulse (t->pulse());
3308                                         }
3309                                         if ((m = dynamic_cast<MeterSection*>(prev)) != 0) {
3310                                                 ts->set_pulse (m->pulse());
3311                                         }
3312                                         ts->set_frame (prev->frame());
3313
3314                                 }
3315                                 if (ms) {
3316                                         if ((m = dynamic_cast<MeterSection*>(prev)) != 0) {
3317                                                 pair<double, BBT_Time> start = make_pair (m->beat(), m->bbt());
3318                                                 ms->set_beat (start);
3319                                                 ms->set_pulse (m->pulse());
3320                                         }
3321                                         if ((t = dynamic_cast<TempoSection*>(prev)) != 0) {
3322                                                 if (!t->active()) {
3323                                                         continue;
3324                                                 }
3325                                                 const double beat = beat_at_pulse_locked (_metrics, t->pulse());
3326                                                 pair<double, BBT_Time> start = make_pair (beat, bbt_at_beat_locked (_metrics, beat));
3327                                                 ms->set_beat (start);
3328                                                 ms->set_pulse (t->pulse());
3329                                         }
3330                                         ms->set_frame (prev->frame());
3331                                 }
3332
3333                         } else {
3334                                 // metric will be at frames=0 bbt=1|1|0 by default
3335                                 // which is correct for our purpose
3336                         }
3337
3338                         // cerr << bbt << endl;
3339
3340                         if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
3341                                 if (!t->active()) {
3342                                         continue;
3343                                 }
3344                                 t->set_pulse (pulse_at_frame_locked (_metrics, m->frame()));
3345                                 tempo = t;
3346                                 // cerr << "NEW TEMPO, frame = " << (*i)->frame() << " beat = " << (*i)->pulse() <<endl;
3347                         } else if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
3348                                 bbt_time (m->frame(), bbt);
3349
3350                                 // cerr << "timestamp @ " << (*i)->frame() << " with " << bbt.bars << "|" << bbt.beats << "|" << bbt.ticks << " => ";
3351
3352                                 if (first) {
3353                                         first = false;
3354                                 } else {
3355
3356                                         if (bbt.ticks > BBT_Time::ticks_per_beat/2) {
3357                                                 /* round up to next beat */
3358                                                 bbt.beats += 1;
3359                                         }
3360
3361                                         bbt.ticks = 0;
3362
3363                                         if (bbt.beats != 1) {
3364                                                 /* round up to next bar */
3365                                                 bbt.bars += 1;
3366                                                 bbt.beats = 1;
3367                                         }
3368                                 }
3369                                 pair<double, BBT_Time> start = make_pair (beat_at_frame_locked (_metrics, m->frame()), bbt);
3370                                 m->set_beat (start);
3371                                 m->set_pulse (pulse_at_frame_locked (_metrics, m->frame()));
3372                                 meter = m;
3373                                 // cerr << "NEW METER, frame = " << (*i)->frame() << " beat = " << (*i)->pulse() <<endl;
3374                         } else {
3375                                 fatal << _("programming error: unhandled MetricSection type") << endmsg;
3376                                 abort(); /*NOTREACHED*/
3377                         }
3378
3379                         prev = (*i);
3380                 }
3381
3382                 recompute_map (_metrics);
3383         }
3384
3385
3386         PropertyChanged (PropertyChange ());
3387 }
3388 bool
3389 TempoMap::remove_time (framepos_t where, framecnt_t amount)
3390 {
3391         bool moved = false;
3392
3393         std::list<MetricSection*> metric_kill_list;
3394
3395         TempoSection* last_tempo = NULL;
3396         MeterSection* last_meter = NULL;
3397         bool tempo_after = false; // is there a tempo marker at the first sample after the removed range?
3398         bool meter_after = false; // is there a meter marker likewise?
3399         {
3400                 Glib::Threads::RWLock::WriterLock lm (lock);
3401                 for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3402                         if ((*i)->frame() >= where && (*i)->frame() < where+amount) {
3403                                 metric_kill_list.push_back(*i);
3404                                 TempoSection *lt = dynamic_cast<TempoSection*> (*i);
3405                                 if (lt)
3406                                         last_tempo = lt;
3407                                 MeterSection *lm = dynamic_cast<MeterSection*> (*i);
3408                                 if (lm)
3409                                         last_meter = lm;
3410                         }
3411                         else if ((*i)->frame() >= where) {
3412                                 // TODO: make sure that moved tempo/meter markers are rounded to beat/bar boundaries
3413                                 (*i)->set_frame ((*i)->frame() - amount);
3414                                 if ((*i)->frame() == where) {
3415                                         // marker was immediately after end of range
3416                                         tempo_after = dynamic_cast<TempoSection*> (*i);
3417                                         meter_after = dynamic_cast<MeterSection*> (*i);
3418                                 }
3419                                 moved = true;
3420                         }
3421                 }
3422
3423                 //find the last TEMPO and METER metric (if any) and move it to the cut point so future stuff is correct
3424                 if (last_tempo && !tempo_after) {
3425                         metric_kill_list.remove(last_tempo);
3426                         last_tempo->set_frame(where);
3427                         moved = true;
3428                 }
3429                 if (last_meter && !meter_after) {
3430                         metric_kill_list.remove(last_meter);
3431                         last_meter->set_frame(where);
3432                         moved = true;
3433                 }
3434
3435                 //remove all the remaining metrics
3436                 for (std::list<MetricSection*>::iterator i = metric_kill_list.begin(); i != metric_kill_list.end(); ++i) {
3437                         _metrics.remove(*i);
3438                         moved = true;
3439                 }
3440
3441                 if (moved) {
3442                         recompute_map (_metrics);
3443                 }
3444         }
3445         PropertyChanged (PropertyChange ());
3446         return moved;
3447 }
3448
3449 /** Add some (fractional) beats to a session frame position, and return the result in frames.
3450  *  pos can be -ve, if required.
3451  */
3452 framepos_t
3453 TempoMap::framepos_plus_beats (framepos_t pos, Evoral::Beats beats) const
3454 {
3455         return frame_at_beat (beat_at_frame (pos) + beats.to_double());
3456 }
3457
3458 /** Subtract some (fractional) beats from a frame position, and return the result in frames */
3459 framepos_t
3460 TempoMap::framepos_minus_beats (framepos_t pos, Evoral::Beats beats) const
3461 {
3462         return frame_at_beat (beat_at_frame (pos) - beats.to_double());
3463 }
3464
3465 /** Add the BBT interval op to pos and return the result */
3466 framepos_t
3467 TempoMap::framepos_plus_bbt (framepos_t pos, BBT_Time op) const
3468 {
3469         Glib::Threads::RWLock::ReaderLock lm (lock);
3470
3471         BBT_Time pos_bbt = bbt_at_beat_locked (_metrics, beat_at_frame_locked (_metrics, pos));
3472         pos_bbt.ticks += op.ticks;
3473         if (pos_bbt.ticks >= BBT_Time::ticks_per_beat) {
3474                 ++pos_bbt.beats;
3475                 pos_bbt.ticks -= BBT_Time::ticks_per_beat;
3476         }
3477         pos_bbt.beats += op.beats;
3478         /* the meter in effect will start on the bar */
3479         double divisions_per_bar = meter_section_at_beat (beat_at_bbt_locked (_metrics, BBT_Time (pos_bbt.bars + op.bars, 1, 0))).divisions_per_bar();
3480         while (pos_bbt.beats >= divisions_per_bar + 1) {
3481                 ++pos_bbt.bars;
3482                 divisions_per_bar = meter_section_at_beat (beat_at_bbt_locked (_metrics, BBT_Time (pos_bbt.bars + op.bars, 1, 0))).divisions_per_bar();
3483                 pos_bbt.beats -= divisions_per_bar;
3484         }
3485         pos_bbt.bars += op.bars;
3486
3487         return frame_time_locked (_metrics, pos_bbt);
3488 }
3489
3490 /** Count the number of beats that are equivalent to distance when going forward,
3491     starting at pos.
3492 */
3493 Evoral::Beats
3494 TempoMap::framewalk_to_beats (framepos_t pos, framecnt_t distance) const
3495 {
3496         return Evoral::Beats (beat_at_frame (pos + distance) - beat_at_frame (pos));
3497 }
3498
3499 struct bbtcmp {
3500     bool operator() (const BBT_Time& a, const BBT_Time& b) {
3501             return a < b;
3502     }
3503 };
3504
3505 std::ostream&
3506 operator<< (std::ostream& o, const Meter& m) {
3507         return o << m.divisions_per_bar() << '/' << m.note_divisor();
3508 }
3509
3510 std::ostream&
3511 operator<< (std::ostream& o, const Tempo& t) {
3512         return o << t.beats_per_minute() << " 1/" << t.note_type() << "'s per minute";
3513 }
3514
3515 std::ostream&
3516 operator<< (std::ostream& o, const MetricSection& section) {
3517
3518         o << "MetricSection @ " << section.frame() << ' ';
3519
3520         const TempoSection* ts;
3521         const MeterSection* ms;
3522
3523         if ((ts = dynamic_cast<const TempoSection*> (&section)) != 0) {
3524                 o << *((const Tempo*) ts);
3525         } else if ((ms = dynamic_cast<const MeterSection*> (&section)) != 0) {
3526                 o << *((const Meter*) ms);
3527         }
3528
3529         return o;
3530 }