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::Ramp, 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                         recompute_map (_metrics);
1003                 }
1004         }
1005
1006         PropertyChanged (PropertyChange ());
1007 }
1008
1009 MeterSection*
1010 TempoMap::add_meter_locked (const Meter& meter, double beat, const Timecode::BBT_Time& where, framepos_t frame, PositionLockStyle pls, bool recompute)
1011 {
1012         const MeterSection& prev_m = meter_section_at_locked  (_metrics, frame - 1);
1013         const double pulse = ((where.bars - prev_m.bbt().bars) * (prev_m.divisions_per_bar() / prev_m.note_divisor())) + prev_m.pulse();
1014
1015         if (pls == AudioTime) {
1016                 /* add meter-locked tempo */
1017                 add_tempo_locked (tempo_at_frame_locked (_metrics, frame), pulse,  frame, TempoSection::Ramp, AudioTime, true, true);
1018         }
1019
1020         MeterSection* new_meter = new MeterSection (pulse, frame, beat, where, meter.divisions_per_bar(), meter.note_divisor(), pls);
1021
1022         do_insert (new_meter);
1023
1024         if (recompute) {
1025
1026                 if (pls == AudioTime) {
1027                         solve_map_frame (_metrics, new_meter, frame);
1028                 } else {
1029                         solve_map_bbt (_metrics, new_meter, where);
1030                 }
1031         }
1032
1033         return new_meter;
1034 }
1035
1036 void
1037 TempoMap::change_initial_tempo (double beats_per_minute, double note_type)
1038 {
1039         Tempo newtempo (beats_per_minute, note_type);
1040         TempoSection* t;
1041
1042         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1043                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1044                         if (!t->active()) {
1045                                 continue;
1046                         }
1047                         {
1048                                 Glib::Threads::RWLock::WriterLock lm (lock);
1049                                 *((Tempo*) t) = newtempo;
1050                                 recompute_map (_metrics);
1051                         }
1052                         PropertyChanged (PropertyChange ());
1053                         break;
1054                 }
1055         }
1056 }
1057
1058 void
1059 TempoMap::change_existing_tempo_at (framepos_t where, double beats_per_minute, double note_type)
1060 {
1061         Tempo newtempo (beats_per_minute, note_type);
1062
1063         TempoSection* prev;
1064         TempoSection* first;
1065         Metrics::iterator i;
1066
1067         /* find the TempoSection immediately preceding "where"
1068          */
1069
1070         for (first = 0, i = _metrics.begin(), prev = 0; i != _metrics.end(); ++i) {
1071
1072                 if ((*i)->frame() > where) {
1073                         break;
1074                 }
1075
1076                 TempoSection* t;
1077
1078                 if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
1079                         if (!t->active()) {
1080                                 continue;
1081                         }
1082                         if (!first) {
1083                                 first = t;
1084                         }
1085                         prev = t;
1086                 }
1087         }
1088
1089         if (!prev) {
1090                 if (!first) {
1091                         error << string_compose (_("no tempo sections defined in tempo map - cannot change tempo @ %1"), where) << endmsg;
1092                         return;
1093                 }
1094
1095                 prev = first;
1096         }
1097
1098         /* reset */
1099
1100         {
1101                 Glib::Threads::RWLock::WriterLock lm (lock);
1102                 /* cannot move the first tempo section */
1103                 *((Tempo*)prev) = newtempo;
1104                 recompute_map (_metrics);
1105         }
1106
1107         PropertyChanged (PropertyChange ());
1108 }
1109
1110 const MeterSection&
1111 TempoMap::first_meter () const
1112 {
1113         const MeterSection *m = 0;
1114
1115         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1116                 if ((m = dynamic_cast<const MeterSection *> (*i)) != 0) {
1117                         return *m;
1118                 }
1119         }
1120
1121         fatal << _("programming error: no meter section in tempo map!") << endmsg;
1122         abort(); /*NOTREACHED*/
1123         return *m;
1124 }
1125
1126 MeterSection&
1127 TempoMap::first_meter ()
1128 {
1129         MeterSection *m = 0;
1130
1131         /* CALLER MUST HOLD LOCK */
1132
1133         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1134                 if ((m = dynamic_cast<MeterSection *> (*i)) != 0) {
1135                         return *m;
1136                 }
1137         }
1138
1139         fatal << _("programming error: no tempo section in tempo map!") << endmsg;
1140         abort(); /*NOTREACHED*/
1141         return *m;
1142 }
1143
1144 const TempoSection&
1145 TempoMap::first_tempo () const
1146 {
1147         const TempoSection *t = 0;
1148
1149         /* CALLER MUST HOLD LOCK */
1150
1151         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1152                 if ((t = dynamic_cast<const TempoSection *> (*i)) != 0) {
1153                         if (!t->active()) {
1154                                 continue;
1155                         }
1156                         if (!t->movable()) {
1157                                 return *t;
1158                         }
1159                 }
1160         }
1161
1162         fatal << _("programming error: no tempo section in tempo map!") << endmsg;
1163         abort(); /*NOTREACHED*/
1164         return *t;
1165 }
1166
1167 TempoSection&
1168 TempoMap::first_tempo ()
1169 {
1170         TempoSection *t = 0;
1171
1172         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1173                 if ((t = dynamic_cast<TempoSection *> (*i)) != 0) {
1174                         if (!t->active()) {
1175                                 continue;
1176                         }
1177                         if (!t->movable()) {
1178                                 return *t;
1179                         }
1180                 }
1181         }
1182
1183         fatal << _("programming error: no tempo section in tempo map!") << endmsg;
1184         abort(); /*NOTREACHED*/
1185         return *t;
1186 }
1187 void
1188 TempoMap::recompute_tempos (Metrics& metrics)
1189 {
1190         TempoSection* prev_t = 0;
1191
1192         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1193                 TempoSection* t;
1194
1195                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1196                         if (!t->active()) {
1197                                 continue;
1198                         }
1199                         if (!t->movable()) {
1200                                 if (!prev_t) {
1201                                         t->set_pulse (0.0);
1202                                         prev_t = t;
1203                                         continue;
1204                                 }
1205                         }
1206                         if (prev_t) {
1207                                 if (t->position_lock_style() == AudioTime) {
1208                                         prev_t->set_c_func (prev_t->compute_c_func_frame (t->pulses_per_minute(), t->frame(), _frame_rate));
1209                                         if (!t->locked_to_meter()) {
1210                                                 t->set_pulse (prev_t->pulse_at_tempo (t->pulses_per_minute(), t->frame(), _frame_rate));
1211                                         }
1212
1213                                 } else {
1214                                         prev_t->set_c_func (prev_t->compute_c_func_pulse (t->pulses_per_minute(), t->pulse(), _frame_rate));
1215                                         t->set_frame (prev_t->frame_at_tempo (t->pulses_per_minute(), t->pulse(), _frame_rate));
1216
1217                                 }
1218                         }
1219                         prev_t = t;
1220                 }
1221         }
1222         prev_t->set_c_func (0.0);
1223 }
1224
1225 /* tempos must be positioned correctly.
1226    the current approach is to use a meter's bbt time as its base position unit.
1227    an audio-locked meter requires a recomputation of pulse and beat (but not bbt),
1228    while a music-locked meter requires recomputations of frame pulse and beat (but not bbt)
1229 */
1230 void
1231 TempoMap::recompute_meters (Metrics& metrics)
1232 {
1233         MeterSection* meter = 0;
1234         MeterSection* prev_m = 0;
1235
1236         for (Metrics::const_iterator mi = metrics.begin(); mi != metrics.end(); ++mi) {
1237                 if ((meter = dynamic_cast<MeterSection*> (*mi)) != 0) {
1238                         if (meter->position_lock_style() == AudioTime) {
1239                                 double pulse = 0.0;
1240                                 pair<double, BBT_Time> b_bbt;
1241                                 TempoSection* meter_locked_tempo = 0;
1242                                 for (Metrics::const_iterator ii = metrics.begin(); ii != metrics.end(); ++ii) {
1243                                         TempoSection* t;
1244                                         if ((t = dynamic_cast<TempoSection*> (*ii)) != 0) {
1245                                                 if ((t->locked_to_meter() || !t->movable()) && t->frame() == meter->frame()) {
1246                                                         meter_locked_tempo = t;
1247                                                         break;
1248                                                 }
1249                                         }
1250                                 }
1251
1252                                 if (prev_m) {
1253                                         const double beats = (meter->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar();
1254                                         if (beats + prev_m->beat() != meter->beat()) {
1255                                                 /* reordering caused a bbt change */
1256                                                 b_bbt = make_pair (beats + prev_m->beat()
1257                                                                    , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
1258                                                 pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
1259
1260                                         } else if (meter->movable()) {
1261                                                 b_bbt = make_pair (meter->beat(), meter->bbt());
1262                                                 pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
1263                                         }
1264                                 } else {
1265                                         b_bbt = make_pair (0.0, BBT_Time (1, 1, 0));
1266                                 }
1267                                 if (meter_locked_tempo) {
1268                                         meter_locked_tempo->set_pulse (pulse);
1269                                 }
1270                                 meter->set_beat (b_bbt);
1271                                 meter->set_pulse (pulse);
1272
1273                         } else {
1274                                 /* MusicTime */
1275                                 double pulse = 0.0;
1276                                 pair<double, BBT_Time> b_bbt;
1277                                 if (prev_m) {
1278                                         const double beats = (meter->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar();
1279                                         if (beats + prev_m->beat() != meter->beat()) {
1280                                                 /* reordering caused a bbt change */
1281                                                 b_bbt = make_pair (beats + prev_m->beat()
1282                                                                    , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
1283                                         } else {
1284                                                 b_bbt = make_pair (beats + prev_m->beat(), meter->bbt());
1285                                         }
1286                                         pulse = (beats / prev_m->note_divisor()) + prev_m->pulse();
1287                                 } else {
1288                                         /* shouldn't happen - the first is audio-locked */
1289                                         pulse = pulse_at_beat_locked (metrics, meter->beat());
1290                                         b_bbt = make_pair (meter->beat(), meter->bbt());
1291                                 }
1292
1293                                 meter->set_beat (b_bbt);
1294                                 meter->set_pulse (pulse);
1295                                 meter->set_frame (frame_at_pulse_locked (metrics, pulse));
1296                         }
1297
1298                         prev_m = meter;
1299                 }
1300         }
1301 }
1302
1303 void
1304 TempoMap::recompute_map (Metrics& metrics, framepos_t end)
1305 {
1306         /* CALLER MUST HOLD WRITE LOCK */
1307
1308         if (end < 0) {
1309
1310                 /* we will actually stop once we hit
1311                    the last metric.
1312                 */
1313                 end = max_framepos;
1314
1315         }
1316
1317         DEBUG_TRACE (DEBUG::TempoMath, string_compose ("recomputing tempo map, zero to %1\n", end));
1318
1319         if (end == 0) {
1320                 /* silly call from Session::process() during startup
1321                  */
1322                 return;
1323         }
1324
1325         recompute_tempos (metrics);
1326         recompute_meters (metrics);
1327 }
1328
1329 TempoMetric
1330 TempoMap::metric_at (framepos_t frame, Metrics::const_iterator* last) const
1331 {
1332         Glib::Threads::RWLock::ReaderLock lm (lock);
1333         TempoMetric m (first_meter(), first_tempo());
1334
1335         /* at this point, we are *guaranteed* to have m.meter and m.tempo pointing
1336            at something, because we insert the default tempo and meter during
1337            TempoMap construction.
1338
1339            now see if we can find better candidates.
1340         */
1341
1342         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1343
1344                 if ((*i)->frame() > frame) {
1345                         break;
1346                 }
1347
1348                 m.set_metric(*i);
1349
1350                 if (last) {
1351                         *last = i;
1352                 }
1353         }
1354
1355         return m;
1356 }
1357
1358 /* XX meters only */
1359 TempoMetric
1360 TempoMap::metric_at (BBT_Time bbt) const
1361 {
1362         Glib::Threads::RWLock::ReaderLock lm (lock);
1363         TempoMetric m (first_meter(), first_tempo());
1364
1365         /* at this point, we are *guaranteed* to have m.meter and m.tempo pointing
1366            at something, because we insert the default tempo and meter during
1367            TempoMap construction.
1368
1369            now see if we can find better candidates.
1370         */
1371
1372         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
1373                 MeterSection* mw;
1374                 if ((mw = dynamic_cast<MeterSection*> (*i)) != 0) {
1375                         BBT_Time section_start (mw->bbt());
1376
1377                         if (section_start.bars > bbt.bars || (section_start.bars == bbt.bars && section_start.beats > bbt.beats)) {
1378                                 break;
1379                         }
1380
1381                         m.set_metric (*i);
1382                 }
1383         }
1384
1385         return m;
1386 }
1387
1388 double
1389 TempoMap::beat_at_frame (const framecnt_t& frame) const
1390 {
1391         Glib::Threads::RWLock::ReaderLock lm (lock);
1392         return beat_at_frame_locked (_metrics, frame);
1393 }
1394
1395 /* meter / tempo section based */
1396 double
1397 TempoMap::beat_at_frame_locked (const Metrics& metrics, const framecnt_t& frame) const
1398 {
1399         const TempoSection& ts = tempo_section_at_locked (metrics, frame);
1400         MeterSection* prev_m = 0;
1401         MeterSection* next_m = 0;
1402
1403         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1404                 MeterSection* m;
1405                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1406                         if (prev_m && m->frame() > frame) {
1407                                 next_m = m;
1408                                 break;
1409                         }
1410                         prev_m = m;
1411                 }
1412         }
1413         if (frame < prev_m->frame()) {
1414                 return 0.0;
1415         }
1416         const double beat = prev_m->beat() + (ts.pulse_at_frame (frame, _frame_rate) - prev_m->pulse()) * prev_m->note_divisor();
1417
1418         if (next_m && next_m->beat() < beat) {
1419                 return next_m->beat();
1420         }
1421
1422         return beat;
1423 }
1424
1425 framecnt_t
1426 TempoMap::frame_at_beat (const double& beat) const
1427 {
1428         Glib::Threads::RWLock::ReaderLock lm (lock);
1429         return frame_at_beat_locked (_metrics, beat);
1430 }
1431
1432 /* meter section based */
1433 framecnt_t
1434 TempoMap::frame_at_beat_locked (const Metrics& metrics, const double& beat) const
1435 {
1436         const TempoSection& prev_t = tempo_section_at_beat_locked (metrics, beat);
1437         MeterSection* prev_m = 0;
1438
1439         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1440                 MeterSection* m;
1441                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1442                         if (prev_m && m->beat() > beat) {
1443                                 break;
1444                         }
1445                         prev_m = m;
1446                 }
1447         }
1448
1449         return prev_t.frame_at_pulse (((beat - prev_m->beat()) / prev_m->note_divisor()) + prev_m->pulse(), _frame_rate);
1450 }
1451
1452 double
1453 TempoMap::pulse_at_beat (const double& beat) const
1454 {
1455         Glib::Threads::RWLock::ReaderLock lm (lock);
1456         return pulse_at_beat_locked (_metrics, beat);
1457 }
1458
1459 double
1460 TempoMap::pulse_at_beat_locked (const Metrics& metrics, const double& beat) const
1461 {
1462         MeterSection* prev_m = 0;
1463
1464         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1465                 MeterSection* m;
1466                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1467                         if (prev_m && m->beat() > beat) {
1468                                 break;
1469                         }
1470                         prev_m = m;
1471                 }
1472
1473         }
1474         double const ret = prev_m->pulse() + ((beat - prev_m->beat()) / prev_m->note_divisor());
1475         return ret;
1476 }
1477
1478 double
1479 TempoMap::beat_at_pulse (const double& pulse) const
1480 {
1481         Glib::Threads::RWLock::ReaderLock lm (lock);
1482         return beat_at_pulse_locked (_metrics, pulse);
1483 }
1484
1485 double
1486 TempoMap::beat_at_pulse_locked (const Metrics& metrics, const double& pulse) const
1487 {
1488         MeterSection* prev_m = 0;
1489
1490         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1491                 MeterSection* m;
1492                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1493                         if (prev_m && m->pulse() > pulse) {
1494                                 if (((pulse - prev_m->pulse()) * prev_m->note_divisor()) + prev_m->beat() > m->beat()) {
1495                                         break;
1496                                 }
1497                         }
1498                         prev_m = m;
1499                 }
1500         }
1501
1502         double const ret = ((pulse - prev_m->pulse()) * prev_m->note_divisor()) + prev_m->beat();
1503         return ret;
1504 }
1505
1506 double
1507 TempoMap::pulse_at_frame (const framecnt_t& frame) const
1508 {
1509         Glib::Threads::RWLock::ReaderLock lm (lock);
1510         return pulse_at_frame_locked (_metrics, frame);
1511 }
1512
1513 /* tempo section based */
1514 double
1515 TempoMap::pulse_at_frame_locked (const Metrics& metrics, const framecnt_t& frame) const
1516 {
1517         /* HOLD (at least) THE READER LOCK */
1518         TempoSection* prev_t = 0;
1519
1520         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1521                 TempoSection* t;
1522                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1523                         if (!t->active()) {
1524                                 continue;
1525                         }
1526                         if (prev_t && t->frame() > frame) {
1527                                 /*the previous ts is the one containing the frame */
1528                                 const double ret = prev_t->pulse_at_frame (frame, _frame_rate);
1529                                 return ret;
1530                         }
1531                         prev_t = t;
1532                 }
1533         }
1534
1535         /* treated as constant for this ts */
1536         const double pulses_in_section = (frame - prev_t->frame()) / prev_t->frames_per_pulse (_frame_rate);
1537
1538         return pulses_in_section + prev_t->pulse();
1539 }
1540
1541 framecnt_t
1542 TempoMap::frame_at_pulse (const double& pulse) const
1543 {
1544         Glib::Threads::RWLock::ReaderLock lm (lock);
1545         return frame_at_pulse_locked (_metrics, pulse);
1546 }
1547
1548 /* tempo section based */
1549 framecnt_t
1550 TempoMap::frame_at_pulse_locked (const Metrics& metrics, const double& pulse) const
1551 {
1552         /* HOLD THE READER LOCK */
1553
1554         const TempoSection* prev_t = 0;
1555
1556         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1557                 TempoSection* t;
1558
1559                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1560                         if (!t->active()) {
1561                                 continue;
1562                         }
1563                         if (prev_t && t->pulse() > pulse) {
1564                                 return prev_t->frame_at_pulse (pulse, _frame_rate);
1565                         }
1566
1567                         prev_t = t;
1568                 }
1569         }
1570         /* must be treated as constant, irrespective of _type */
1571         double const pulses_in_section = pulse - prev_t->pulse();
1572         double const dtime = pulses_in_section * prev_t->frames_per_pulse (_frame_rate);
1573
1574         framecnt_t const ret = (framecnt_t) floor (dtime) + prev_t->frame();
1575
1576         return ret;
1577 }
1578
1579 const Tempo
1580 TempoMap::tempo_at_frame (const framepos_t& frame) const
1581 {
1582         Glib::Threads::RWLock::ReaderLock lm (lock);
1583         return tempo_at_frame_locked (_metrics, frame);
1584 }
1585
1586 const Tempo
1587 TempoMap::tempo_at_frame_locked (const Metrics& metrics, const framepos_t& frame) const
1588 {
1589         TempoSection* prev_t = 0;
1590
1591         Metrics::const_iterator i;
1592
1593         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
1594                 TempoSection* t;
1595                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1596                         if (!t->active()) {
1597                                 continue;
1598                         }
1599                         if ((prev_t) && t->frame() > frame) {
1600                                 /* t is the section past frame */
1601                                 const double ret_bpm = prev_t->tempo_at_frame (frame, _frame_rate) * prev_t->note_type();
1602                                 const Tempo ret_tempo (ret_bpm, prev_t->note_type());
1603                                 return ret_tempo;
1604                         }
1605                         prev_t = t;
1606                 }
1607         }
1608
1609         const double ret = prev_t->beats_per_minute();
1610         const Tempo ret_tempo (ret, prev_t->note_type ());
1611
1612         return ret_tempo;
1613 }
1614
1615
1616 double
1617 TempoMap::beat_at_bbt (const Timecode::BBT_Time& bbt)
1618 {
1619         Glib::Threads::RWLock::ReaderLock lm (lock);
1620         return beat_at_bbt_locked (_metrics, bbt);
1621 }
1622
1623
1624 double
1625 TempoMap::beat_at_bbt_locked (const Metrics& metrics, const Timecode::BBT_Time& bbt) const
1626 {
1627         /* CALLER HOLDS READ LOCK */
1628
1629         MeterSection* prev_m = 0;
1630
1631         /* because audio-locked meters have 'fake' integral beats,
1632            there is no pulse offset here.
1633         */
1634         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1635                 MeterSection* m;
1636                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1637                         if (prev_m) {
1638                                 const double bars_to_m = (m->beat() - prev_m->beat()) / prev_m->divisions_per_bar();
1639                                 if ((bars_to_m + (prev_m->bbt().bars - 1)) > (bbt.bars - 1)) {
1640                                         break;
1641                                 }
1642                         }
1643                         prev_m = m;
1644                 }
1645         }
1646
1647         const double remaining_bars = bbt.bars - prev_m->bbt().bars;
1648         const double remaining_bars_in_beats = remaining_bars * prev_m->divisions_per_bar();
1649         const double ret = remaining_bars_in_beats + prev_m->beat() + (bbt.beats - 1) + (bbt.ticks / BBT_Time::ticks_per_beat);
1650
1651         return ret;
1652 }
1653
1654 Timecode::BBT_Time
1655 TempoMap::bbt_at_beat (const double& beats)
1656 {
1657         Glib::Threads::RWLock::ReaderLock lm (lock);
1658         return bbt_at_beat_locked (_metrics, beats);
1659 }
1660
1661 Timecode::BBT_Time
1662 TempoMap::bbt_at_beat_locked (const Metrics& metrics, const double& b) const
1663 {
1664         /* CALLER HOLDS READ LOCK */
1665         MeterSection* prev_m = 0;
1666         const double beats = max (0.0, b);
1667
1668         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1669                 MeterSection* m = 0;
1670
1671                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1672                         if (prev_m) {
1673                                 if (m->beat() > beats) {
1674                                         /* this is the meter after the one our beat is on*/
1675                                         break;
1676                                 }
1677                         }
1678
1679                         prev_m = m;
1680                 }
1681         }
1682
1683         const double beats_in_ms = beats - prev_m->beat();
1684         const uint32_t bars_in_ms = (uint32_t) floor (beats_in_ms / prev_m->divisions_per_bar());
1685         const uint32_t total_bars = bars_in_ms + (prev_m->bbt().bars - 1);
1686         const double remaining_beats = beats_in_ms - (bars_in_ms * prev_m->divisions_per_bar());
1687         const double remaining_ticks = (remaining_beats - floor (remaining_beats)) * BBT_Time::ticks_per_beat;
1688
1689         BBT_Time ret;
1690
1691         ret.ticks = (uint32_t) floor (remaining_ticks + 0.5);
1692         ret.beats = (uint32_t) floor (remaining_beats);
1693         ret.bars = total_bars;
1694
1695         /* 0 0 0 to 1 1 0 - based mapping*/
1696         ++ret.bars;
1697         ++ret.beats;
1698
1699         if (ret.ticks >= BBT_Time::ticks_per_beat) {
1700                 ++ret.beats;
1701                 ret.ticks -= BBT_Time::ticks_per_beat;
1702         }
1703
1704         if (ret.beats >= prev_m->divisions_per_bar() + 1) {
1705                 ++ret.bars;
1706                 ret.beats = 1;
1707         }
1708
1709         return ret;
1710 }
1711
1712 double
1713 TempoMap::pulse_at_bbt (const Timecode::BBT_Time& bbt)
1714 {
1715         Glib::Threads::RWLock::ReaderLock lm (lock);
1716
1717         return pulse_at_bbt_locked (_metrics, bbt);
1718 }
1719
1720 double
1721 TempoMap::pulse_at_bbt_locked (const Metrics& metrics, const Timecode::BBT_Time& bbt) const
1722 {
1723         /* CALLER HOLDS READ LOCK */
1724
1725         MeterSection* prev_m = 0;
1726
1727         /* because audio-locked meters have 'fake' integral beats,
1728            there is no pulse offset here.
1729         */
1730         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1731                 MeterSection* m;
1732                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1733                         if (prev_m) {
1734                                 if (m->bbt().bars > bbt.bars) {
1735                                         break;
1736                                 }
1737                         }
1738                         prev_m = m;
1739                 }
1740         }
1741
1742         const double remaining_bars = bbt.bars - prev_m->bbt().bars;
1743         const double remaining_pulses = remaining_bars * prev_m->divisions_per_bar() / prev_m->note_divisor();
1744         const double ret = remaining_pulses + prev_m->pulse() + (((bbt.beats - 1) + (bbt.ticks / BBT_Time::ticks_per_beat)) / prev_m->note_divisor());
1745
1746         return ret;
1747 }
1748
1749 Timecode::BBT_Time
1750 TempoMap::bbt_at_pulse (const double& pulse)
1751 {
1752         Glib::Threads::RWLock::ReaderLock lm (lock);
1753
1754         return bbt_at_pulse_locked (_metrics, pulse);
1755 }
1756
1757 Timecode::BBT_Time
1758 TempoMap::bbt_at_pulse_locked (const Metrics& metrics, const double& pulse) const
1759 {
1760         MeterSection* prev_m = 0;
1761
1762         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1763                 MeterSection* m = 0;
1764
1765                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1766
1767                         if (prev_m) {
1768                                 double const pulses_to_m = m->pulse() - prev_m->pulse();
1769                                 if (prev_m->pulse() + pulses_to_m > pulse) {
1770                                         /* this is the meter after the one our beat is on*/
1771                                         break;
1772                                 }
1773                         }
1774
1775                         prev_m = m;
1776                 }
1777         }
1778
1779         const double beats_in_ms = (pulse - prev_m->pulse()) * prev_m->note_divisor();
1780         const uint32_t bars_in_ms = (uint32_t) floor (beats_in_ms / prev_m->divisions_per_bar());
1781         const uint32_t total_bars = bars_in_ms + (prev_m->bbt().bars - 1);
1782         const double remaining_beats = beats_in_ms - (bars_in_ms * prev_m->divisions_per_bar());
1783         const double remaining_ticks = (remaining_beats - floor (remaining_beats)) * BBT_Time::ticks_per_beat;
1784
1785         BBT_Time ret;
1786
1787         ret.ticks = (uint32_t) floor (remaining_ticks + 0.5);
1788         ret.beats = (uint32_t) floor (remaining_beats);
1789         ret.bars = total_bars;
1790
1791         /* 0 0 0 to 1 1 0 mapping*/
1792         ++ret.bars;
1793         ++ret.beats;
1794
1795         if (ret.ticks >= BBT_Time::ticks_per_beat) {
1796                 ++ret.beats;
1797                 ret.ticks -= BBT_Time::ticks_per_beat;
1798         }
1799
1800         if (ret.beats >= prev_m->divisions_per_bar() + 1) {
1801                 ++ret.bars;
1802                 ret.beats = 1;
1803         }
1804
1805         return ret;
1806 }
1807
1808 void
1809 TempoMap::bbt_time (framepos_t frame, BBT_Time& bbt)
1810 {
1811
1812         if (frame < 0) {
1813                 bbt.bars = 1;
1814                 bbt.beats = 1;
1815                 bbt.ticks = 0;
1816                 warning << string_compose (_("tempo map asked for BBT time at frame %1\n"), frame) << endmsg;
1817                 return;
1818         }
1819         Glib::Threads::RWLock::ReaderLock lm (lock);
1820         const double beat = beat_at_frame_locked (_metrics, frame);
1821
1822         bbt = bbt_at_beat_locked (_metrics, beat);
1823 }
1824
1825 framepos_t
1826 TempoMap::frame_time (const BBT_Time& bbt)
1827 {
1828         if (bbt.bars < 1) {
1829                 warning << string_compose (_("tempo map asked for frame time at bar < 1  (%1)\n"), bbt) << endmsg;
1830                 return 0;
1831         }
1832
1833         if (bbt.beats < 1) {
1834                 throw std::logic_error ("beats are counted from one");
1835         }
1836         Glib::Threads::RWLock::ReaderLock lm (lock);
1837
1838         return frame_time_locked (_metrics, bbt);
1839 }
1840
1841 /* meter section based */
1842 framepos_t
1843 TempoMap::frame_time_locked (const Metrics& metrics, const BBT_Time& bbt) const
1844 {
1845         /* HOLD THE READER LOCK */
1846
1847         const framepos_t ret = frame_at_beat_locked (metrics, beat_at_bbt_locked (metrics, bbt));
1848         return ret;
1849 }
1850
1851 bool
1852 TempoMap::check_solved (const Metrics& metrics) const
1853 {
1854         TempoSection* prev_t = 0;
1855         MeterSection* prev_m = 0;
1856
1857         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1858                 TempoSection* t;
1859                 MeterSection* m;
1860                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1861                         if (!t->active()) {
1862                                 continue;
1863                         }
1864                         if (prev_t) {
1865                                 if ((t->frame() <= prev_t->frame()) || (t->pulse() <= prev_t->pulse())) {
1866                                         return false;
1867                                 }
1868
1869                                 /* precision check ensures tempo and frames align.*/
1870                                 if (t->frame() != prev_t->frame_at_tempo (t->pulses_per_minute(), t->pulse(), _frame_rate)) {
1871                                         if (!t->locked_to_meter()) {
1872                                                 return false;
1873                                         }
1874                                 }
1875                         }
1876                         prev_t = t;
1877                 }
1878
1879                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1880                         if (prev_m && m->position_lock_style() == AudioTime) {
1881                                 TempoSection* t = const_cast<TempoSection*>(&tempo_section_at_locked (metrics, m->frame() - 1));
1882                                 const double nascent_m_pulse = ((m->beat() - prev_m->beat()) / prev_m->note_divisor()) + prev_m->pulse();
1883                                 const framepos_t nascent_m_frame = t->frame_at_pulse (nascent_m_pulse, _frame_rate);
1884
1885                                 if (t && (nascent_m_frame > m->frame() || nascent_m_frame < 0)) {
1886                                         return false;
1887                                 }
1888                         }
1889
1890                         prev_m = m;
1891                 }
1892
1893         }
1894
1895         return true;
1896 }
1897
1898 bool
1899 TempoMap::set_active_tempos (const Metrics& metrics, const framepos_t& frame)
1900 {
1901         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
1902                 TempoSection* t;
1903                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1904                         if (!t->movable()) {
1905                                 t->set_active (true);
1906                                 continue;
1907                         }
1908                         if (t->movable() && t->active () && t->position_lock_style() == AudioTime && t->frame() < frame) {
1909                                 t->set_active (false);
1910                                 t->set_pulse (0.0);
1911                         } else if (t->movable() && t->position_lock_style() == AudioTime && t->frame() > frame) {
1912                                 t->set_active (true);
1913                         } else if (t->movable() && t->position_lock_style() == AudioTime && t->frame() == frame) {
1914                                 return false;
1915                         }
1916                 }
1917         }
1918         return true;
1919 }
1920
1921 bool
1922 TempoMap::solve_map_frame (Metrics& imaginary, TempoSection* section, const framepos_t& frame)
1923 {
1924         TempoSection* prev_t = 0;
1925         TempoSection* section_prev = 0;
1926         framepos_t first_m_frame = 0;
1927
1928         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
1929                 MeterSection* m;
1930                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
1931                         if (!m->movable()) {
1932                                 first_m_frame = m->frame();
1933                                 break;
1934                         }
1935                 }
1936         }
1937         if (section->movable() && frame <= first_m_frame) {
1938                 return false;
1939         }
1940
1941         section->set_active (true);
1942         section->set_frame (frame);
1943
1944         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
1945                 TempoSection* t;
1946                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
1947
1948                         if (!t->active()) {
1949                                 continue;
1950                         }
1951                         if (prev_t) {
1952                                 if (t == section) {
1953                                         section_prev = prev_t;
1954                                         continue;
1955                                 }
1956                                 if (t->position_lock_style() == MusicTime) {
1957                                         prev_t->set_c_func (prev_t->compute_c_func_pulse (t->pulses_per_minute(), t->pulse(), _frame_rate));
1958                                         t->set_frame (prev_t->frame_at_pulse (t->pulse(), _frame_rate));
1959                                 } else {
1960                                         prev_t->set_c_func (prev_t->compute_c_func_frame (t->pulses_per_minute(), t->frame(), _frame_rate));
1961                                         if (!t->locked_to_meter()) {
1962                                                 t->set_pulse (prev_t->pulse_at_frame (t->frame(), _frame_rate));
1963                                         }
1964                                 }
1965                         }
1966                         prev_t = t;
1967                 }
1968         }
1969
1970         if (section_prev) {
1971                 section_prev->set_c_func (section_prev->compute_c_func_frame (section->pulses_per_minute(), frame, _frame_rate));
1972                 if (!section->locked_to_meter()) {
1973                         section->set_pulse (section_prev->pulse_at_frame (frame, _frame_rate));
1974                 }
1975         }
1976
1977         recompute_tempos (imaginary);
1978
1979         if (check_solved (imaginary)) {
1980                 return true;
1981         }
1982
1983         MetricSectionFrameSorter fcmp;
1984         imaginary.sort (fcmp);
1985
1986         recompute_tempos (imaginary);
1987
1988         if (check_solved (imaginary)) {
1989                 return true;
1990         }
1991
1992         return false;
1993 }
1994
1995 bool
1996 TempoMap::solve_map_pulse (Metrics& imaginary, TempoSection* section, const double& pulse)
1997 {
1998         TempoSection* prev_t = 0;
1999         TempoSection* section_prev = 0;
2000
2001         section->set_pulse (pulse);
2002
2003         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2004                 TempoSection* t;
2005                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2006                         if (!t->active()) {
2007                                 continue;
2008                         }
2009                         if (!t->movable()) {
2010                                 t->set_pulse (0.0);
2011                                 prev_t = t;
2012                                 continue;
2013                         }
2014                         if (prev_t) {
2015                                 if (t == section) {
2016                                         section_prev = prev_t;
2017                                         continue;
2018                                 }
2019                                 if (t->position_lock_style() == MusicTime) {
2020                                         prev_t->set_c_func (prev_t->compute_c_func_pulse (t->pulses_per_minute(), t->pulse(), _frame_rate));
2021                                         t->set_frame (prev_t->frame_at_pulse (t->pulse(), _frame_rate));
2022                                 } else {
2023                                         prev_t->set_c_func (prev_t->compute_c_func_frame (t->pulses_per_minute(), t->frame(), _frame_rate));
2024                                         if (!t->locked_to_meter()) {
2025                                                 t->set_pulse (prev_t->pulse_at_frame (t->frame(), _frame_rate));
2026                                         }
2027                                 }
2028                         }
2029                         prev_t = t;
2030                 }
2031         }
2032
2033         if (section_prev) {
2034                 section_prev->set_c_func (section_prev->compute_c_func_pulse (section->pulses_per_minute(), pulse, _frame_rate));
2035                 section->set_frame (section_prev->frame_at_pulse (pulse, _frame_rate));
2036         }
2037
2038         recompute_tempos (imaginary);
2039
2040         if (check_solved (imaginary)) {
2041                 return true;
2042         }
2043
2044         MetricSectionSorter cmp;
2045         imaginary.sort (cmp);
2046
2047         recompute_tempos (imaginary);
2048         /* Reordering
2049          * XX need a restriction here, but only for this case,
2050          * as audio locked tempos don't interact in the same way.
2051          *
2052          * With music-locked tempos, the solution to cross-dragging can fly off the screen
2053          * e.g.
2054          * |50 bpm                        |250 bpm |60 bpm
2055          *                drag 250 to the pulse after 60->
2056          * a clue: dragging the second 60 <- past the 250 would cause no such problem.
2057          */
2058         if (check_solved (imaginary)) {
2059                 return true;
2060         }
2061
2062         return false;
2063 }
2064
2065 bool
2066 TempoMap::solve_map_frame (Metrics& imaginary, MeterSection* section, const framepos_t& frame)
2067 {
2068         /* disallow moving first meter past any subsequent one, and any movable meter before the first one */
2069         const MeterSection* other =  &meter_section_at_locked (imaginary, frame);
2070         if ((!section->movable() && other->movable()) || (!other->movable() && section->movable() && other->frame() >= frame)) {
2071                 return false;
2072         }
2073
2074         if (!section->movable()) {
2075                 /* lock the first tempo to our first meter */
2076                 if (!set_active_tempos (imaginary, frame)) {
2077                         return false;
2078                 }
2079         }
2080
2081         /* it would make sense to bail out if there is no audio-locked meter,
2082            however it may be desirable to move a music-locked meter by frame at some point.
2083         */
2084         TempoSection* meter_locked_tempo = 0;
2085         for (Metrics::const_iterator ii = imaginary.begin(); ii != imaginary.end(); ++ii) {
2086                 TempoSection* t;
2087                 if ((t = dynamic_cast<TempoSection*> (*ii)) != 0) {
2088                         if ((t->locked_to_meter() || !t->movable()) && t->frame() == section->frame()) {
2089                                 meter_locked_tempo = t;
2090                                 break;
2091                         }
2092                 }
2093         }
2094
2095         if (!meter_locked_tempo) {
2096                 return false;
2097         }
2098
2099         MeterSection* prev_m = 0;
2100         Metrics future_map;
2101         TempoSection* tempo_copy = copy_metrics_and_point (imaginary, future_map, meter_locked_tempo);
2102         bool solved = false;
2103
2104         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2105                 MeterSection* m;
2106                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2107                         if (m == section){
2108                                 if (prev_m && section->movable()) {
2109                                         const double beats = (pulse_at_frame_locked (imaginary, frame) - prev_m->pulse()) * prev_m->note_divisor();
2110                                         if (beats + prev_m->beat() < section->beat()) {
2111                                                 /* set the frame/pulse corresponding to its musical position,
2112                                                  * as an earlier time than this has been requested.
2113                                                 */
2114                                                 const double new_pulse = ((section->beat() - prev_m->beat())
2115                                                                           / prev_m->note_divisor()) + prev_m->pulse();
2116
2117                                                 const framepos_t smallest_frame = frame_at_pulse_locked (future_map, new_pulse);
2118
2119                                                 if ((solved = solve_map_frame (future_map, tempo_copy, smallest_frame))) {
2120                                                         meter_locked_tempo->set_pulse (new_pulse);
2121                                                         solve_map_frame (imaginary, meter_locked_tempo, smallest_frame);
2122                                                         section->set_frame (smallest_frame);
2123                                                         section->set_pulse (new_pulse);
2124                                                 } else {
2125                                                         solved = false;
2126                                                 }
2127
2128                                                 Metrics::const_iterator d = future_map.begin();
2129                                                 while (d != future_map.end()) {
2130                                                         delete (*d);
2131                                                         ++d;
2132                                                 }
2133
2134                                                 if (!solved) {
2135                                                         return false;
2136                                                 }
2137                                         } else {
2138                                                 /* all is ok. set section's tempo */
2139                                                 MeterSection* meter_copy = const_cast<MeterSection*> (&meter_section_at_locked (future_map, section->frame()));
2140                                                 meter_copy->set_frame (frame);
2141
2142                                                 if ((solved = solve_map_frame (future_map, tempo_copy, frame))) {
2143                                                         section->set_frame (frame);
2144                                                         meter_locked_tempo->set_pulse (((section->beat() - prev_m->beat())
2145                                                                                                 / prev_m->note_divisor()) + prev_m->pulse());
2146                                                         solve_map_frame (imaginary, meter_locked_tempo, frame);
2147                                                 } else {
2148                                                         solved = false;
2149                                                 }
2150
2151                                                 Metrics::const_iterator d = future_map.begin();
2152                                                 while (d != future_map.end()) {
2153                                                         delete (*d);
2154                                                         ++d;
2155                                                 }
2156
2157                                                 if (!solved) {
2158                                                         return false;
2159                                                 }
2160                                         }
2161                                 } else {
2162                                         /* not movable (first meter atm) */
2163
2164                                         tempo_copy->set_frame (frame);
2165                                         tempo_copy->set_pulse (0.0);
2166
2167                                         if ((solved = solve_map_frame (future_map, tempo_copy, frame))) {
2168                                                 section->set_frame (frame);
2169                                                 meter_locked_tempo->set_frame (frame);
2170                                                 meter_locked_tempo->set_pulse (0.0);
2171                                                 solve_map_frame (imaginary, meter_locked_tempo, frame);
2172                                         } else {
2173                                                 solved = false;
2174                                         }
2175
2176                                         Metrics::const_iterator d = future_map.begin();
2177                                         while (d != future_map.end()) {
2178                                                 delete (*d);
2179                                                 ++d;
2180                                         }
2181
2182                                         if (!solved) {
2183                                                 return false;
2184                                         }
2185
2186                                         pair<double, BBT_Time> b_bbt = make_pair (0.0, BBT_Time (1, 1, 0));
2187                                         section->set_beat (b_bbt);
2188                                         section->set_pulse (0.0);
2189
2190                                 }
2191                                 break;
2192                         }
2193
2194                         prev_m = m;
2195                 }
2196         }
2197
2198         MetricSectionFrameSorter fcmp;
2199         imaginary.sort (fcmp);
2200
2201         recompute_meters (imaginary);
2202
2203         return true;
2204 }
2205
2206 bool
2207 TempoMap::solve_map_bbt (Metrics& imaginary, MeterSection* section, const BBT_Time& when)
2208 {
2209         /* disallow setting section to an existing meter's bbt */
2210         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2211                 MeterSection* m;
2212                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2213                         if (m != section && m->bbt().bars == when.bars) {
2214                                 return false;
2215                         }
2216                 }
2217         }
2218
2219         MeterSection* prev_m = 0;
2220         MeterSection* section_prev = 0;
2221
2222         for (Metrics::iterator i = imaginary.begin(); i != imaginary.end(); ++i) {
2223                 MeterSection* m;
2224                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2225                         pair<double, BBT_Time> b_bbt;
2226                         double new_pulse = 0.0;
2227
2228                         if (prev_m && m->bbt().bars > when.bars && !section_prev){
2229                                 section_prev = prev_m;
2230                                 const double beats = (when.bars - section_prev->bbt().bars) * section_prev->divisions_per_bar();
2231                                 const double pulse = (beats / section_prev->note_divisor()) + section_prev->pulse();
2232                                 pair<double, BBT_Time> b_bbt = make_pair (beats + section_prev->beat(), when);
2233
2234                                 section->set_beat (b_bbt);
2235                                 section->set_pulse (pulse);
2236                                 section->set_frame (frame_at_pulse_locked (imaginary, pulse));
2237                                 prev_m = section;
2238                                 continue;
2239                         }
2240
2241                         if (m->position_lock_style() == AudioTime) {
2242                                 TempoSection* meter_locked_tempo = 0;
2243
2244                                 for (Metrics::const_iterator ii = imaginary.begin(); ii != imaginary.end(); ++ii) {
2245                                         TempoSection* t;
2246                                         if ((t = dynamic_cast<TempoSection*> (*ii)) != 0) {
2247                                                 if ((t->locked_to_meter() || !t->movable()) && t->frame() == m->frame()) {
2248                                                         meter_locked_tempo = t;
2249                                                         break;
2250                                                 }
2251                                         }
2252                                 }
2253
2254                                 if (!meter_locked_tempo) {
2255                                         return false;
2256                                 }
2257
2258                                 if (prev_m) {
2259                                         const double beats = ((m->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar());
2260
2261                                         if (beats + prev_m->beat() != m->beat()) {
2262                                                 /* tempo/ meter change caused a change in beat (bar). */
2263                                                 b_bbt = make_pair (beats + prev_m->beat()
2264                                                                    , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
2265                                                 new_pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
2266                                         } else if (m->movable()) {
2267                                                 b_bbt = make_pair (m->beat(), m->bbt());
2268                                                 new_pulse = prev_m->pulse() + (beats / prev_m->note_divisor());
2269                                         }
2270                                 } else {
2271                                         b_bbt = make_pair (0.0, BBT_Time (1, 1, 0));
2272                                 }
2273
2274                                 meter_locked_tempo->set_pulse (new_pulse);
2275                                 m->set_beat (b_bbt);
2276                                 m->set_pulse (new_pulse);
2277
2278                         } else {
2279                                 /* MusicTime */
2280                                 const double beats = ((m->bbt().bars - prev_m->bbt().bars) * prev_m->divisions_per_bar());
2281                                 if (beats + prev_m->beat() != m->beat()) {
2282                                         /* tempo/ meter change caused a change in beat (bar). */
2283                                         b_bbt = make_pair (beats + prev_m->beat()
2284                                                            , BBT_Time ((beats / prev_m->divisions_per_bar()) + prev_m->bbt().bars, 1, 0));
2285                                 } else {
2286                                         b_bbt = make_pair (beats + prev_m->beat()
2287                                                            , m->bbt());
2288                                 }
2289                                 new_pulse = (beats / prev_m->note_divisor()) + prev_m->pulse();
2290                                 m->set_beat (b_bbt);
2291                                 m->set_pulse (new_pulse);
2292                                 m->set_frame (frame_at_pulse_locked (imaginary, new_pulse));
2293                         }
2294
2295                         prev_m = m;
2296                 }
2297         }
2298
2299         if (!section_prev) {
2300
2301                 const double beats = (when.bars - prev_m->bbt().bars) * prev_m->divisions_per_bar();
2302                 const double pulse = (beats / prev_m->note_divisor()) + prev_m->pulse();
2303                 pair<double, BBT_Time> b_bbt = make_pair (beats + prev_m->beat(), when);
2304
2305                 section->set_beat (b_bbt);
2306                 section->set_pulse (pulse);
2307                 section->set_frame (frame_at_pulse_locked (imaginary, pulse));
2308         }
2309
2310         MetricSectionSorter cmp;
2311         imaginary.sort (cmp);
2312
2313         recompute_meters (imaginary);
2314
2315         return true;
2316 }
2317
2318 /** places a copy of _metrics into copy and returns a pointer
2319  *  to section's equivalent in copy.
2320  */
2321 TempoSection*
2322 TempoMap::copy_metrics_and_point (const Metrics& metrics, Metrics& copy, TempoSection* section)
2323 {
2324         TempoSection* ret = 0;
2325
2326         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2327                 TempoSection* t;
2328                 MeterSection* m;
2329                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2330                         if (t == section) {
2331                                 ret = new TempoSection (*t);
2332                                 copy.push_back (ret);
2333                                 continue;
2334                         }
2335
2336                         TempoSection* cp = new TempoSection (*t);
2337                         copy.push_back (cp);
2338                 }
2339                 if ((m = dynamic_cast<MeterSection *> (*i)) != 0) {
2340                         MeterSection* cp = new MeterSection (*m);
2341                         copy.push_back (cp);
2342                 }
2343         }
2344
2345         return ret;
2346 }
2347
2348 MeterSection*
2349 TempoMap::copy_metrics_and_point (const Metrics& metrics, Metrics& copy, MeterSection* section)
2350 {
2351         MeterSection* ret = 0;
2352
2353         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2354                 TempoSection* t;
2355                 MeterSection* m;
2356                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2357                         TempoSection* cp = new TempoSection (*t);
2358                         copy.push_back (cp);
2359                 }
2360
2361                 if ((m = dynamic_cast<MeterSection *> (*i)) != 0) {
2362                         if (m == section) {
2363                                 ret = new MeterSection (*m);
2364                                 copy.push_back (ret);
2365                                 continue;
2366                         }
2367                         MeterSection* cp = new MeterSection (*m);
2368                         copy.push_back (cp);
2369                 }
2370         }
2371
2372         return ret;
2373 }
2374
2375 /** answers the question "is this a valid beat position for this tempo section?".
2376  *  it returns true if the tempo section can be moved to the requested bbt position,
2377  *  leaving the tempo map in a solved state.
2378  * @param section the tempo section to be moved
2379  * @param bbt the requested new position for the tempo section
2380  * @return true if the tempo section can be moved to the position, otherwise false.
2381  */
2382 bool
2383 TempoMap::can_solve_bbt (TempoSection* ts, const BBT_Time& bbt)
2384 {
2385         Metrics copy;
2386         TempoSection* tempo_copy = 0;
2387
2388         {
2389                 Glib::Threads::RWLock::ReaderLock lm (lock);
2390                 tempo_copy = copy_metrics_and_point (_metrics, copy, ts);
2391                 if (!tempo_copy) {
2392                         return false;
2393                 }
2394         }
2395
2396         const bool ret = solve_map_pulse (copy, tempo_copy, pulse_at_bbt_locked (copy, bbt));
2397
2398         Metrics::const_iterator d = copy.begin();
2399         while (d != copy.end()) {
2400                 delete (*d);
2401                 ++d;
2402         }
2403
2404         return ret;
2405 }
2406
2407 /**
2408 * 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,
2409 * taking any possible reordering as a consequence of this into account.
2410 * @param section - the section to be altered
2411 * @param bbt - the bbt where the altered tempo will fall
2412 * @return returns - the position in pulses and frames (as a pair) where the new tempo section will lie.
2413 */
2414 pair<double, framepos_t>
2415 TempoMap::predict_tempo_position (TempoSection* section, const BBT_Time& bbt)
2416 {
2417         Metrics future_map;
2418         pair<double, framepos_t> ret = make_pair (0.0, 0);
2419
2420         Glib::Threads::RWLock::ReaderLock lm (lock);
2421
2422         TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, section);
2423
2424         const double beat = beat_at_bbt_locked (future_map, bbt);
2425
2426         if (solve_map_pulse (future_map, tempo_copy, pulse_at_beat_locked (future_map, beat))) {
2427                 ret.first = tempo_copy->pulse();
2428                 ret.second = tempo_copy->frame();
2429         } else {
2430                 ret.first = section->pulse();
2431                 ret.second = section->frame();
2432         }
2433
2434         Metrics::const_iterator d = future_map.begin();
2435         while (d != future_map.end()) {
2436                 delete (*d);
2437                 ++d;
2438         }
2439         return ret;
2440 }
2441
2442 void
2443 TempoMap::gui_move_tempo (TempoSection* ts, const framepos_t& frame)
2444 {
2445         Metrics future_map;
2446
2447         if (ts->position_lock_style() == MusicTime) {
2448                 {
2449                         Glib::Threads::RWLock::WriterLock lm (lock);
2450                         TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, ts);
2451                         const double pulse = pulse_at_frame_locked (future_map, frame);
2452                         if (solve_map_pulse (future_map, tempo_copy, pulse)) {
2453                                 solve_map_pulse (_metrics, ts, pulse);
2454                                 recompute_meters (_metrics);
2455                         }
2456                 }
2457
2458         } else {
2459
2460                 {
2461                         Glib::Threads::RWLock::WriterLock lm (lock);
2462                         TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, ts);
2463                         if (solve_map_frame (future_map, tempo_copy, frame)) {
2464                                 solve_map_frame (_metrics, ts, frame);
2465                                 recompute_meters (_metrics);
2466                         }
2467                 }
2468         }
2469
2470         Metrics::const_iterator d = future_map.begin();
2471         while (d != future_map.end()) {
2472                 delete (*d);
2473                 ++d;
2474         }
2475
2476         MetricPositionChanged (); // Emit Signal
2477 }
2478
2479 void
2480 TempoMap::gui_move_meter (MeterSection* ms, const framepos_t& frame)
2481 {
2482         Metrics future_map;
2483
2484         if (ms->position_lock_style() == AudioTime) {
2485
2486                 {
2487                         Glib::Threads::RWLock::WriterLock lm (lock);
2488                         MeterSection* copy = copy_metrics_and_point (_metrics, future_map, ms);
2489
2490                         if (solve_map_frame (future_map, copy, frame)) {
2491                                 solve_map_frame (_metrics, ms, frame);
2492                                 recompute_tempos (_metrics);
2493                         }
2494                 }
2495         } else {
2496                 {
2497                         Glib::Threads::RWLock::WriterLock lm (lock);
2498                         MeterSection* copy = copy_metrics_and_point (_metrics, future_map, ms);
2499
2500                         const double beat = beat_at_frame_locked (_metrics, frame);
2501                         const Timecode::BBT_Time bbt = bbt_at_beat_locked (_metrics, beat);
2502
2503                         if (solve_map_bbt (future_map, copy, bbt)) {
2504                                 solve_map_bbt (_metrics, ms, bbt);
2505                                 recompute_tempos (_metrics);
2506                         }
2507                 }
2508         }
2509
2510         Metrics::const_iterator d = future_map.begin();
2511         while (d != future_map.end()) {
2512                 delete (*d);
2513                 ++d;
2514         }
2515
2516         MetricPositionChanged (); // Emit Signal
2517 }
2518
2519 bool
2520 TempoMap::gui_change_tempo (TempoSection* ts, const Tempo& bpm)
2521 {
2522         Metrics future_map;
2523         bool can_solve = false;
2524         {
2525                 Glib::Threads::RWLock::WriterLock lm (lock);
2526                 TempoSection* tempo_copy = copy_metrics_and_point (_metrics, future_map, ts);
2527                 tempo_copy->set_beats_per_minute (bpm.beats_per_minute());
2528                 recompute_tempos (future_map);
2529
2530                 if (check_solved (future_map)) {
2531                         ts->set_beats_per_minute (bpm.beats_per_minute());
2532                         recompute_map (_metrics);
2533                         can_solve = true;
2534                 }
2535         }
2536
2537         Metrics::const_iterator d = future_map.begin();
2538         while (d != future_map.end()) {
2539                 delete (*d);
2540                 ++d;
2541         }
2542         if (can_solve) {
2543                 MetricPositionChanged (); // Emit Signal
2544         }
2545         return can_solve;
2546 }
2547
2548 void
2549 TempoMap::gui_dilate_tempo (TempoSection* ts, const framepos_t& frame, const framepos_t& end_frame, const double& pulse)
2550 {
2551         /*
2552           Ts (future prev_t)   Tnext
2553           |                    |
2554           |     [drag^]        |
2555           |----------|----------
2556                 e_f  pulse(frame)
2557         */
2558
2559         Metrics future_map;
2560
2561         {
2562                 Glib::Threads::RWLock::WriterLock lm (lock);
2563
2564                 if (!ts) {
2565                         return;
2566                 }
2567
2568                 TempoSection* prev_t = copy_metrics_and_point (_metrics, future_map, ts);
2569                 TempoSection* prev_to_prev_t = 0;
2570                 const frameoffset_t fr_off = end_frame - frame;
2571
2572                 if (prev_t && prev_t->pulse() > 0.0) {
2573                         prev_to_prev_t = const_cast<TempoSection*>(&tempo_section_at_locked (future_map, prev_t->frame() - 1));
2574                 }
2575
2576                 TempoSection* next_t = 0;
2577                 for (Metrics::iterator i = future_map.begin(); i != future_map.end(); ++i) {
2578                         TempoSection* t = 0;
2579                         if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2580                                 if (t->frame() > ts->frame()) {
2581                                         next_t = t;
2582                                         break;
2583                                 }
2584                         }
2585                 }
2586
2587                 /* the change in frames is the result of changing the slope of at most 2 previous tempo sections.
2588                    constant to constant is straightforward, as the tempo prev to prev_t has constant slope.
2589                 */
2590                 double contribution = 0.0;
2591                 double start_pulse = prev_t->pulse_at_frame (frame, _frame_rate);
2592
2593                 if (next_t && prev_to_prev_t && prev_to_prev_t->type() == TempoSection::Ramp) {
2594                         contribution = (prev_t->frame() - prev_to_prev_t->frame()) / (double) (next_t->frame() - prev_to_prev_t->frame());
2595                 }
2596
2597                 frameoffset_t prev_t_frame_contribution = fr_off - (contribution * (double) fr_off);
2598                 double end_pulse = prev_t->pulse_at_frame (end_frame, _frame_rate);
2599                 double new_bpm;
2600
2601                 if (prev_t->type() == TempoSection::Constant || prev_t->c_func() == 0.0) {
2602
2603                         if (prev_t->position_lock_style() == MusicTime) {
2604                                 if (prev_to_prev_t && prev_to_prev_t->type() == TempoSection::Ramp) {
2605
2606                                         new_bpm = prev_t->beats_per_minute() * ((frame - prev_to_prev_t->frame())
2607                                                                                 / (double) ((frame + prev_t_frame_contribution) - prev_to_prev_t->frame()));
2608
2609                                 } else {
2610                                         /* prev to prev is irrelevant */
2611
2612                                         if (start_pulse != prev_t->pulse()) {
2613                                                 new_bpm = prev_t->beats_per_minute() * ((start_pulse - prev_t->pulse()) / (end_pulse - prev_t->pulse()));
2614                                         } else {
2615                                                 new_bpm = prev_t->beats_per_minute();
2616                                         }
2617                                 }
2618                         } else {
2619                                 /* AudioTime */
2620                                 if (prev_to_prev_t && prev_to_prev_t->type() == TempoSection::Ramp) {
2621                                         new_bpm = prev_t->beats_per_minute() * ((frame - prev_t->frame())
2622                                                                                 / (double) ((frame + prev_t_frame_contribution) - prev_t->frame()));
2623                                 } else {
2624                                         /* prev_to_prev_t is irrelevant */
2625
2626                                         if (end_frame != prev_t->frame()) {
2627                                                 new_bpm = prev_t->beats_per_minute() * ((frame - prev_t->frame()) / (double) (end_frame - prev_t->frame()));
2628                                         } else {
2629                                                 new_bpm = prev_t->beats_per_minute();
2630                                         }
2631                                 }
2632                         }
2633                 } else {
2634
2635                         double frame_ratio;
2636                         double pulse_ratio;
2637                         const framepos_t pulse_pos = prev_t->frame_at_pulse (pulse, _frame_rate);
2638
2639                         if (prev_to_prev_t) {
2640
2641                                 frame_ratio = (((pulse_pos - fr_off) - prev_to_prev_t->frame()) / (double) ((pulse_pos) - prev_to_prev_t->frame()));
2642                                 pulse_ratio = ((start_pulse - prev_to_prev_t->pulse()) / (end_pulse - prev_to_prev_t->pulse()));
2643                         } else {
2644
2645                                 frame_ratio = (((pulse_pos - fr_off) - prev_t->frame()) / (double) ((pulse_pos) - prev_t->frame()));
2646                                 pulse_ratio = (start_pulse / end_pulse);
2647                         }
2648                         new_bpm = prev_t->beats_per_minute() * (pulse_ratio * frame_ratio);
2649                 }
2650
2651                 prev_t->set_beats_per_minute (new_bpm);
2652                 recompute_tempos (future_map);
2653                 recompute_meters (future_map);
2654
2655                 if (check_solved (future_map)) {
2656                         ts->set_beats_per_minute (new_bpm);
2657                         recompute_tempos (_metrics);
2658                         recompute_meters (_metrics);
2659                 }
2660         }
2661
2662         Metrics::const_iterator d = future_map.begin();
2663         while (d != future_map.end()) {
2664                 delete (*d);
2665                 ++d;
2666         }
2667
2668         MetricPositionChanged (); // Emit Signal
2669 }
2670
2671 framecnt_t
2672 TempoMap::bbt_duration_at (framepos_t pos, const BBT_Time& bbt, int dir)
2673 {
2674         Glib::Threads::RWLock::ReaderLock lm (lock);
2675
2676         const double tick_at_time = beat_at_frame_locked (_metrics, pos) * BBT_Time::ticks_per_beat;
2677         const double bbt_ticks = bbt.ticks + (bbt.beats * BBT_Time::ticks_per_beat);
2678         const double total_beats = (tick_at_time + bbt_ticks) / BBT_Time::ticks_per_beat;
2679
2680         return frame_at_beat_locked (_metrics, total_beats);
2681 }
2682
2683 framepos_t
2684 TempoMap::round_to_bar (framepos_t fr, RoundMode dir)
2685 {
2686         return round_to_type (fr, dir, Bar);
2687 }
2688
2689 framepos_t
2690 TempoMap::round_to_beat (framepos_t fr, RoundMode dir)
2691 {
2692         return round_to_type (fr, dir, Beat);
2693 }
2694
2695 framepos_t
2696 TempoMap::round_to_beat_subdivision (framepos_t fr, int sub_num, RoundMode dir)
2697 {
2698         Glib::Threads::RWLock::ReaderLock lm (lock);
2699         uint32_t ticks = (uint32_t) floor (beat_at_frame_locked (_metrics, fr) * BBT_Time::ticks_per_beat);
2700         uint32_t beats = (uint32_t) floor (ticks / BBT_Time::ticks_per_beat);
2701         uint32_t ticks_one_subdivisions_worth = (uint32_t) BBT_Time::ticks_per_beat / sub_num;
2702
2703         ticks -= beats * BBT_Time::ticks_per_beat;
2704
2705         if (dir > 0) {
2706                 /* round to next (or same iff dir == RoundUpMaybe) */
2707
2708                 uint32_t mod = ticks % ticks_one_subdivisions_worth;
2709
2710                 if (mod == 0 && dir == RoundUpMaybe) {
2711                         /* right on the subdivision, which is fine, so do nothing */
2712
2713                 } else if (mod == 0) {
2714                         /* right on the subdivision, so the difference is just the subdivision ticks */
2715                         ticks += ticks_one_subdivisions_worth;
2716
2717                 } else {
2718                         /* not on subdivision, compute distance to next subdivision */
2719
2720                         ticks += ticks_one_subdivisions_worth - mod;
2721                 }
2722
2723                 if (ticks >= BBT_Time::ticks_per_beat) {
2724                         ticks -= BBT_Time::ticks_per_beat;
2725                 }
2726         } else if (dir < 0) {
2727
2728                 /* round to previous (or same iff dir == RoundDownMaybe) */
2729
2730                 uint32_t difference = ticks % ticks_one_subdivisions_worth;
2731
2732                 if (difference == 0 && dir == RoundDownAlways) {
2733                         /* right on the subdivision, but force-rounding down,
2734                            so the difference is just the subdivision ticks */
2735                         difference = ticks_one_subdivisions_worth;
2736                 }
2737
2738                 if (ticks < difference) {
2739                         ticks = BBT_Time::ticks_per_beat - ticks;
2740                 } else {
2741                         ticks -= difference;
2742                 }
2743
2744         } else {
2745                 /* round to nearest */
2746                 double rem;
2747
2748                 /* compute the distance to the previous and next subdivision */
2749
2750                 if ((rem = fmod ((double) ticks, (double) ticks_one_subdivisions_worth)) > ticks_one_subdivisions_worth/2.0) {
2751
2752                         /* closer to the next subdivision, so shift forward */
2753
2754                         ticks = lrint (ticks + (ticks_one_subdivisions_worth - rem));
2755
2756                         DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("moved forward to %1\n", ticks));
2757
2758                         if (ticks > BBT_Time::ticks_per_beat) {
2759                                 ++beats;
2760                                 ticks -= BBT_Time::ticks_per_beat;
2761                                 DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("fold beat to %1\n", beats));
2762                         }
2763
2764                 } else if (rem > 0) {
2765
2766                         /* closer to previous subdivision, so shift backward */
2767
2768                         if (rem > ticks) {
2769                                 if (beats == 0) {
2770                                         /* can't go backwards past zero, so ... */
2771                                         return 0;
2772                                 }
2773                                 /* step back to previous beat */
2774                                 --beats;
2775                                 ticks = lrint (BBT_Time::ticks_per_beat - rem);
2776                                 DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("step back beat to %1\n", beats));
2777                         } else {
2778                                 ticks = lrint (ticks - rem);
2779                                 DEBUG_TRACE (DEBUG::SnapBBT, string_compose ("moved backward to %1\n", ticks));
2780                         }
2781                 } else {
2782                         /* on the subdivision, do nothing */
2783                 }
2784         }
2785
2786         const framepos_t ret_frame = frame_at_beat_locked (_metrics, beats + (ticks / BBT_Time::ticks_per_beat));
2787
2788         return ret_frame;
2789 }
2790
2791 framepos_t
2792 TempoMap::round_to_type (framepos_t frame, RoundMode dir, BBTPointType type)
2793 {
2794         Glib::Threads::RWLock::ReaderLock lm (lock);
2795
2796         const double beat_at_framepos = beat_at_frame_locked (_metrics, frame);
2797         BBT_Time bbt (bbt_at_beat_locked (_metrics, beat_at_framepos));
2798
2799         switch (type) {
2800         case Bar:
2801                 if (dir < 0) {
2802                         /* find bar previous to 'frame' */
2803                         bbt.beats = 1;
2804                         bbt.ticks = 0;
2805                         return frame_time_locked (_metrics, bbt);
2806
2807                 } else if (dir > 0) {
2808                         /* find bar following 'frame' */
2809                         ++bbt.bars;
2810                         bbt.beats = 1;
2811                         bbt.ticks = 0;
2812                         return frame_time_locked (_metrics, bbt);
2813                 } else {
2814                         /* true rounding: find nearest bar */
2815                         framepos_t raw_ft = frame_time_locked (_metrics, bbt);
2816                         bbt.beats = 1;
2817                         bbt.ticks = 0;
2818                         framepos_t prev_ft = frame_time_locked (_metrics, bbt);
2819                         ++bbt.bars;
2820                         framepos_t next_ft = frame_time_locked (_metrics, bbt);
2821
2822                         if ((raw_ft - prev_ft) > (next_ft - prev_ft) / 2) {
2823                                 return next_ft;
2824                         } else {
2825                                 return prev_ft;
2826                         }
2827                 }
2828
2829                 break;
2830
2831         case Beat:
2832                 if (dir < 0) {
2833                         return frame_at_beat_locked (_metrics, floor (beat_at_framepos));
2834                 } else if (dir > 0) {
2835                         return frame_at_beat_locked (_metrics, ceil (beat_at_framepos));
2836                 } else {
2837                         return frame_at_beat_locked (_metrics, floor (beat_at_framepos + 0.5));
2838                 }
2839                 break;
2840         }
2841
2842         return 0;
2843 }
2844
2845 void
2846 TempoMap::get_grid (vector<TempoMap::BBTPoint>& points,
2847                     framepos_t lower, framepos_t upper)
2848 {
2849         Glib::Threads::RWLock::ReaderLock lm (lock);
2850         int32_t cnt = ceil (beat_at_frame_locked (_metrics, lower));
2851         framecnt_t pos = 0;
2852         /* although the map handles negative beats, bbt doesn't. */
2853         if (cnt < 0.0) {
2854                 cnt = 0.0;
2855         }
2856         while (pos < upper) {
2857                 pos = frame_at_beat_locked (_metrics, cnt);
2858                 const TempoSection tempo = tempo_section_at_locked (_metrics, pos);
2859                 const MeterSection meter = meter_section_at_locked (_metrics, pos);
2860                 const BBT_Time bbt = bbt_at_beat_locked (_metrics, cnt);
2861                 points.push_back (BBTPoint (meter, tempo_at_frame_locked (_metrics, pos), pos, bbt.bars, bbt.beats, tempo.c_func()));
2862                 ++cnt;
2863         }
2864 }
2865
2866 const TempoSection&
2867 TempoMap::tempo_section_at (framepos_t frame) const
2868 {
2869         Glib::Threads::RWLock::ReaderLock lm (lock);
2870         return tempo_section_at_locked (_metrics, frame);
2871 }
2872
2873 const TempoSection&
2874 TempoMap::tempo_section_at_locked (const Metrics& metrics, framepos_t frame) const
2875 {
2876         Metrics::const_iterator i;
2877         TempoSection* prev = 0;
2878
2879         for (i = metrics.begin(); i != metrics.end(); ++i) {
2880                 TempoSection* t;
2881
2882                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2883                         if (!t->active()) {
2884                                 continue;
2885                         }
2886                         if (prev && t->frame() > frame) {
2887                                 break;
2888                         }
2889
2890                         prev = t;
2891                 }
2892         }
2893
2894         if (prev == 0) {
2895                 fatal << endmsg;
2896                 abort(); /*NOTREACHED*/
2897         }
2898
2899         return *prev;
2900 }
2901
2902 const TempoSection&
2903 TempoMap::tempo_section_at_beat_locked (const Metrics& metrics, const double& beat) const
2904 {
2905         TempoSection* prev_t = 0;
2906         const MeterSection* prev_m = &meter_section_at_beat_locked (metrics, beat);
2907
2908         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2909                 TempoSection* t;
2910                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2911                         if (prev_t && ((t->pulse() - prev_m->pulse()) * prev_m->note_divisor()) + prev_m->beat() > beat) {
2912                                 break;
2913                         }
2914                         prev_t = t;
2915                 }
2916
2917         }
2918         return *prev_t;
2919 }
2920
2921 const TempoSection&
2922 TempoMap::tempo_section_at_pulse_locked (const Metrics& metrics, const double& pulse) const
2923 {
2924         TempoSection* prev_t = 0;
2925
2926         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
2927                 TempoSection* t;
2928                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2929                         if (prev_t && t->pulse() > pulse) {
2930                                 break;
2931                         }
2932                         prev_t = t;
2933                 }
2934
2935         }
2936         return *prev_t;
2937 }
2938
2939 /* don't use this to calculate length (the tempo is only correct for this frame).
2940    do that stuff based on the beat_at_frame and frame_at_beat api
2941 */
2942 double
2943 TempoMap::frames_per_beat_at (const framepos_t& frame, const framecnt_t& sr) const
2944 {
2945         Glib::Threads::RWLock::ReaderLock lm (lock);
2946
2947         const TempoSection* ts_at = &tempo_section_at_locked (_metrics, frame);
2948         const TempoSection* ts_after = 0;
2949         Metrics::const_iterator i;
2950
2951         for (i = _metrics.begin(); i != _metrics.end(); ++i) {
2952                 TempoSection* t;
2953
2954                 if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
2955                         if (!t->active()) {
2956                                 continue;
2957                         }
2958                         if ((*i)->frame() > frame) {
2959                                 ts_after = t;
2960                                 break;
2961                         }
2962                 }
2963         }
2964
2965         if (ts_after) {
2966                 return  (60.0 * _frame_rate) / (ts_at->tempo_at_frame (frame, _frame_rate));
2967         }
2968         /* must be treated as constant tempo */
2969         return ts_at->frames_per_beat (_frame_rate);
2970 }
2971
2972 const MeterSection&
2973 TempoMap::meter_section_at_locked (const Metrics& metrics, framepos_t frame) const
2974 {
2975         Metrics::const_iterator i;
2976         MeterSection* prev = 0;
2977
2978         for (i = metrics.begin(); i != metrics.end(); ++i) {
2979                 MeterSection* m;
2980
2981                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
2982
2983                         if (prev && (*i)->frame() > frame) {
2984                                 break;
2985                         }
2986
2987                         prev = m;
2988                 }
2989         }
2990
2991         if (prev == 0) {
2992                 fatal << endmsg;
2993                 abort(); /*NOTREACHED*/
2994         }
2995
2996         return *prev;
2997 }
2998
2999
3000 const MeterSection&
3001 TempoMap::meter_section_at (framepos_t frame) const
3002 {
3003         Glib::Threads::RWLock::ReaderLock lm (lock);
3004         return meter_section_at_locked (_metrics, frame);
3005 }
3006
3007 const MeterSection&
3008 TempoMap::meter_section_at_beat_locked (const Metrics& metrics, const double& beat) const
3009 {
3010         MeterSection* prev_m = 0;
3011
3012         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
3013                 MeterSection* m;
3014                 if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
3015                         if (prev_m && m->beat() > beat) {
3016                                 break;
3017                         }
3018                         prev_m = m;
3019                 }
3020
3021         }
3022         return *prev_m;
3023 }
3024
3025 const MeterSection&
3026 TempoMap::meter_section_at_beat (double beat) const
3027 {
3028         Glib::Threads::RWLock::ReaderLock lm (lock);
3029         return meter_section_at_beat_locked (_metrics, beat);
3030 }
3031
3032 const Meter&
3033 TempoMap::meter_at_frame (framepos_t frame) const
3034 {
3035         TempoMetric m (metric_at (frame));
3036         return m.meter();
3037 }
3038
3039 void
3040 TempoMap::fix_legacy_session ()
3041 {
3042         MeterSection* prev_m = 0;
3043         TempoSection* prev_t = 0;
3044
3045         for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3046                 MeterSection* m;
3047                 TempoSection* t;
3048
3049                 if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
3050                         if (!m->movable()) {
3051                                 pair<double, BBT_Time> bbt = make_pair (0.0, BBT_Time (1, 1, 0));
3052                                 m->set_beat (bbt);
3053                                 m->set_pulse (0.0);
3054                                 m->set_frame (0);
3055                                 m->set_position_lock_style (AudioTime);
3056                                 prev_m = m;
3057                                 continue;
3058                         }
3059                         if (prev_m) {
3060                                 pair<double, BBT_Time> start = make_pair (((m->bbt().bars - 1) * prev_m->note_divisor())
3061                                                                           + (m->bbt().beats - 1)
3062                                                                           + (m->bbt().ticks / BBT_Time::ticks_per_beat)
3063                                                                           , m->bbt());
3064                                 m->set_beat (start);
3065                                 const double start_beat = ((m->bbt().bars - 1) * prev_m->note_divisor())
3066                                         + (m->bbt().beats - 1)
3067                                         + (m->bbt().ticks / BBT_Time::ticks_per_beat);
3068                                 m->set_pulse (start_beat / prev_m->note_divisor());
3069                         }
3070                         prev_m = m;
3071                 } else if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
3072
3073                         if (!t->active()) {
3074                                 continue;
3075                         }
3076
3077                         if (!t->movable()) {
3078                                 t->set_pulse (0.0);
3079                                 t->set_frame (0);
3080                                 t->set_position_lock_style (AudioTime);
3081                                 prev_t = t;
3082                                 continue;
3083                         }
3084
3085                         if (prev_t) {
3086                                 const double beat = ((t->legacy_bbt().bars - 1) * ((prev_m) ? prev_m->note_divisor() : 4.0))
3087                                         + (t->legacy_bbt().beats - 1)
3088                                         + (t->legacy_bbt().ticks / BBT_Time::ticks_per_beat);
3089                                 if (prev_m) {
3090                                         t->set_pulse (beat / prev_m->note_divisor());
3091                                 } else {
3092                                         /* really shouldn't happen but.. */
3093                                         t->set_pulse (beat / 4.0);
3094                                 }
3095                         }
3096                         prev_t = t;
3097                 }
3098         }
3099 }
3100
3101 XMLNode&
3102 TempoMap::get_state ()
3103 {
3104         Metrics::const_iterator i;
3105         XMLNode *root = new XMLNode ("TempoMap");
3106
3107         {
3108                 Glib::Threads::RWLock::ReaderLock lm (lock);
3109                 for (i = _metrics.begin(); i != _metrics.end(); ++i) {
3110                         root->add_child_nocopy ((*i)->get_state());
3111                 }
3112         }
3113
3114         return *root;
3115 }
3116
3117 int
3118 TempoMap::set_state (const XMLNode& node, int /*version*/)
3119 {
3120         {
3121                 Glib::Threads::RWLock::WriterLock lm (lock);
3122
3123                 XMLNodeList nlist;
3124                 XMLNodeConstIterator niter;
3125                 Metrics old_metrics (_metrics);
3126                 _metrics.clear();
3127
3128                 nlist = node.children();
3129
3130                 for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
3131                         XMLNode* child = *niter;
3132
3133                         if (child->name() == TempoSection::xml_state_node_name) {
3134
3135                                 try {
3136                                         TempoSection* ts = new TempoSection (*child);
3137                                         _metrics.push_back (ts);
3138                                 }
3139
3140                                 catch (failed_constructor& err){
3141                                         error << _("Tempo map: could not set new state, restoring old one.") << endmsg;
3142                                         _metrics = old_metrics;
3143                                         break;
3144                                 }
3145
3146                         } else if (child->name() == MeterSection::xml_state_node_name) {
3147
3148                                 try {
3149                                         MeterSection* ms = new MeterSection (*child);
3150                                         _metrics.push_back (ms);
3151                                 }
3152
3153                                 catch (failed_constructor& err) {
3154                                         error << _("Tempo map: could not set new state, restoring old one.") << endmsg;
3155                                         _metrics = old_metrics;
3156                                         break;
3157                                 }
3158                         }
3159                 }
3160
3161                 if (niter == nlist.end()) {
3162                         MetricSectionSorter cmp;
3163                         _metrics.sort (cmp);
3164                 }
3165
3166                 /* check for legacy sessions where bbt was the base musical unit for tempo */
3167                 for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3168                         TempoSection* t;
3169                         if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
3170                                 if (t->legacy_bbt().bars != 0) {
3171                                         fix_legacy_session();
3172                                         break;
3173                                 }
3174                                 break;
3175                         }
3176                 }
3177
3178                 /* check for multiple tempo/meters at the same location, which
3179                    ardour2 somehow allowed.
3180                 */
3181
3182                 Metrics::iterator prev = _metrics.end();
3183                 for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3184                         if (prev != _metrics.end()) {
3185                                 MeterSection* ms;
3186                                 MeterSection* prev_m;
3187                                 TempoSection* ts;
3188                                 TempoSection* prev_t;
3189                                 if ((prev_m = dynamic_cast<MeterSection*>(*prev)) != 0 && (ms = dynamic_cast<MeterSection*>(*i)) != 0) {
3190                                         if (prev_m->pulse() == ms->pulse()) {
3191                                                 cerr << string_compose (_("Multiple meter definitions found at %1"), prev_m->pulse()) << endmsg;
3192                                                 error << string_compose (_("Multiple meter definitions found at %1"), prev_m->pulse()) << endmsg;
3193                                                 return -1;
3194                                         }
3195                                 } else if ((prev_t = dynamic_cast<TempoSection*>(*prev)) != 0 && (ts = dynamic_cast<TempoSection*>(*i)) != 0) {
3196                                         if (prev_t->pulse() == ts->pulse()) {
3197                                                 cerr << string_compose (_("Multiple tempo definitions found at %1"), prev_t->pulse()) << endmsg;
3198                                                 error << string_compose (_("Multiple tempo definitions found at %1"), prev_t->pulse()) << endmsg;
3199                                                 return -1;
3200                                         }
3201                                 }
3202                         }
3203                         prev = i;
3204                 }
3205
3206                 recompute_map (_metrics);
3207         }
3208
3209         PropertyChanged (PropertyChange ());
3210
3211         return 0;
3212 }
3213
3214 void
3215 TempoMap::dump (const Metrics& metrics, std::ostream& o) const
3216 {
3217         Glib::Threads::RWLock::ReaderLock lm (lock, Glib::Threads::TRY_LOCK);
3218         const MeterSection* m;
3219         const TempoSection* t;
3220         const TempoSection* prev_t = 0;
3221
3222         for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
3223
3224                 if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
3225                         o << "Tempo @ " << *i << t->beats_per_minute() << " BPM (pulse = 1/" << t->note_type() << ") at " << t->pulse() << " frame= " << t->frame() << " (movable? "
3226                           << t->movable() << ')' << " pos lock: " << enum_2_string (t->position_lock_style()) << std::endl;
3227                         o << "current      : " << t->beats_per_minute() << " | " << t->pulse() << " | " << t->frame() << std::endl;
3228                         if (prev_t) {
3229                                 o << "previous     : " << prev_t->beats_per_minute() << " | " << prev_t->pulse() << " | " << prev_t->frame() << std::endl;
3230                                 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;
3231                         }
3232                         prev_t = t;
3233                 } else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
3234                         o << "Meter @ " << *i << ' ' << m->divisions_per_bar() << '/' << m->note_divisor() << " at " << m->bbt() << " frame= " << m->frame()
3235                           << " pulse: " << m->pulse() <<  " beat : " << m->beat() << " pos lock: " << enum_2_string (m->position_lock_style()) << " (movable? " << m->movable() << ')' << endl;
3236                 }
3237         }
3238         o << "------" << std::endl;
3239 }
3240
3241 int
3242 TempoMap::n_tempos() const
3243 {
3244         Glib::Threads::RWLock::ReaderLock lm (lock);
3245         int cnt = 0;
3246
3247         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3248                 if (dynamic_cast<const TempoSection*>(*i) != 0) {
3249                         cnt++;
3250                 }
3251         }
3252
3253         return cnt;
3254 }
3255
3256 int
3257 TempoMap::n_meters() const
3258 {
3259         Glib::Threads::RWLock::ReaderLock lm (lock);
3260         int cnt = 0;
3261
3262         for (Metrics::const_iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3263                 if (dynamic_cast<const MeterSection*>(*i) != 0) {
3264                         cnt++;
3265                 }
3266         }
3267
3268         return cnt;
3269 }
3270
3271 void
3272 TempoMap::insert_time (framepos_t where, framecnt_t amount)
3273 {
3274         {
3275                 Glib::Threads::RWLock::WriterLock lm (lock);
3276                 for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3277                         if ((*i)->frame() >= where && (*i)->movable ()) {
3278                                 (*i)->set_frame ((*i)->frame() + amount);
3279                         }
3280                 }
3281
3282                 /* now reset the BBT time of all metrics, based on their new
3283                  * audio time. This is the only place where we do this reverse
3284                  * timestamp.
3285                  */
3286
3287                 Metrics::iterator i;
3288                 const MeterSection* meter;
3289                 const TempoSection* tempo;
3290                 MeterSection *m;
3291                 TempoSection *t;
3292
3293                 meter = &first_meter ();
3294                 tempo = &first_tempo ();
3295
3296                 BBT_Time start;
3297                 BBT_Time end;
3298
3299                 // cerr << "\n###################### TIMESTAMP via AUDIO ##############\n" << endl;
3300
3301                 bool first = true;
3302                 MetricSection* prev = 0;
3303
3304                 for (i = _metrics.begin(); i != _metrics.end(); ++i) {
3305
3306                         BBT_Time bbt;
3307                         //TempoMetric metric (*meter, *tempo);
3308                         MeterSection* ms = const_cast<MeterSection*>(meter);
3309                         TempoSection* ts = const_cast<TempoSection*>(tempo);
3310                         if (prev) {
3311                                 if (ts){
3312                                         if ((t = dynamic_cast<TempoSection*>(prev)) != 0) {
3313                                                 if (!t->active()) {
3314                                                         continue;
3315                                                 }
3316                                                 ts->set_pulse (t->pulse());
3317                                         }
3318                                         if ((m = dynamic_cast<MeterSection*>(prev)) != 0) {
3319                                                 ts->set_pulse (m->pulse());
3320                                         }
3321                                         ts->set_frame (prev->frame());
3322
3323                                 }
3324                                 if (ms) {
3325                                         if ((m = dynamic_cast<MeterSection*>(prev)) != 0) {
3326                                                 pair<double, BBT_Time> start = make_pair (m->beat(), m->bbt());
3327                                                 ms->set_beat (start);
3328                                                 ms->set_pulse (m->pulse());
3329                                         }
3330                                         if ((t = dynamic_cast<TempoSection*>(prev)) != 0) {
3331                                                 if (!t->active()) {
3332                                                         continue;
3333                                                 }
3334                                                 const double beat = beat_at_pulse_locked (_metrics, t->pulse());
3335                                                 pair<double, BBT_Time> start = make_pair (beat, bbt_at_beat_locked (_metrics, beat));
3336                                                 ms->set_beat (start);
3337                                                 ms->set_pulse (t->pulse());
3338                                         }
3339                                         ms->set_frame (prev->frame());
3340                                 }
3341
3342                         } else {
3343                                 // metric will be at frames=0 bbt=1|1|0 by default
3344                                 // which is correct for our purpose
3345                         }
3346
3347                         // cerr << bbt << endl;
3348
3349                         if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
3350                                 if (!t->active()) {
3351                                         continue;
3352                                 }
3353                                 t->set_pulse (pulse_at_frame_locked (_metrics, m->frame()));
3354                                 tempo = t;
3355                                 // cerr << "NEW TEMPO, frame = " << (*i)->frame() << " beat = " << (*i)->pulse() <<endl;
3356                         } else if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
3357                                 bbt_time (m->frame(), bbt);
3358
3359                                 // cerr << "timestamp @ " << (*i)->frame() << " with " << bbt.bars << "|" << bbt.beats << "|" << bbt.ticks << " => ";
3360
3361                                 if (first) {
3362                                         first = false;
3363                                 } else {
3364
3365                                         if (bbt.ticks > BBT_Time::ticks_per_beat/2) {
3366                                                 /* round up to next beat */
3367                                                 bbt.beats += 1;
3368                                         }
3369
3370                                         bbt.ticks = 0;
3371
3372                                         if (bbt.beats != 1) {
3373                                                 /* round up to next bar */
3374                                                 bbt.bars += 1;
3375                                                 bbt.beats = 1;
3376                                         }
3377                                 }
3378                                 pair<double, BBT_Time> start = make_pair (beat_at_frame_locked (_metrics, m->frame()), bbt);
3379                                 m->set_beat (start);
3380                                 m->set_pulse (pulse_at_frame_locked (_metrics, m->frame()));
3381                                 meter = m;
3382                                 // cerr << "NEW METER, frame = " << (*i)->frame() << " beat = " << (*i)->pulse() <<endl;
3383                         } else {
3384                                 fatal << _("programming error: unhandled MetricSection type") << endmsg;
3385                                 abort(); /*NOTREACHED*/
3386                         }
3387
3388                         prev = (*i);
3389                 }
3390
3391                 recompute_map (_metrics);
3392         }
3393
3394
3395         PropertyChanged (PropertyChange ());
3396 }
3397 bool
3398 TempoMap::remove_time (framepos_t where, framecnt_t amount)
3399 {
3400         bool moved = false;
3401
3402         std::list<MetricSection*> metric_kill_list;
3403
3404         TempoSection* last_tempo = NULL;
3405         MeterSection* last_meter = NULL;
3406         bool tempo_after = false; // is there a tempo marker at the first sample after the removed range?
3407         bool meter_after = false; // is there a meter marker likewise?
3408         {
3409                 Glib::Threads::RWLock::WriterLock lm (lock);
3410                 for (Metrics::iterator i = _metrics.begin(); i != _metrics.end(); ++i) {
3411                         if ((*i)->frame() >= where && (*i)->frame() < where+amount) {
3412                                 metric_kill_list.push_back(*i);
3413                                 TempoSection *lt = dynamic_cast<TempoSection*> (*i);
3414                                 if (lt)
3415                                         last_tempo = lt;
3416                                 MeterSection *lm = dynamic_cast<MeterSection*> (*i);
3417                                 if (lm)
3418                                         last_meter = lm;
3419                         }
3420                         else if ((*i)->frame() >= where) {
3421                                 // TODO: make sure that moved tempo/meter markers are rounded to beat/bar boundaries
3422                                 (*i)->set_frame ((*i)->frame() - amount);
3423                                 if ((*i)->frame() == where) {
3424                                         // marker was immediately after end of range
3425                                         tempo_after = dynamic_cast<TempoSection*> (*i);
3426                                         meter_after = dynamic_cast<MeterSection*> (*i);
3427                                 }
3428                                 moved = true;
3429                         }
3430                 }
3431
3432                 //find the last TEMPO and METER metric (if any) and move it to the cut point so future stuff is correct
3433                 if (last_tempo && !tempo_after) {
3434                         metric_kill_list.remove(last_tempo);
3435                         last_tempo->set_frame(where);
3436                         moved = true;
3437                 }
3438                 if (last_meter && !meter_after) {
3439                         metric_kill_list.remove(last_meter);
3440                         last_meter->set_frame(where);
3441                         moved = true;
3442                 }
3443
3444                 //remove all the remaining metrics
3445                 for (std::list<MetricSection*>::iterator i = metric_kill_list.begin(); i != metric_kill_list.end(); ++i) {
3446                         _metrics.remove(*i);
3447                         moved = true;
3448                 }
3449
3450                 if (moved) {
3451                         recompute_map (_metrics);
3452                 }
3453         }
3454         PropertyChanged (PropertyChange ());
3455         return moved;
3456 }
3457
3458 /** Add some (fractional) beats to a session frame position, and return the result in frames.
3459  *  pos can be -ve, if required.
3460  */
3461 framepos_t
3462 TempoMap::framepos_plus_beats (framepos_t pos, Evoral::Beats beats) const
3463 {
3464         return frame_at_beat (beat_at_frame (pos) + beats.to_double());
3465 }
3466
3467 /** Subtract some (fractional) beats from a frame position, and return the result in frames */
3468 framepos_t
3469 TempoMap::framepos_minus_beats (framepos_t pos, Evoral::Beats beats) const
3470 {
3471         return frame_at_beat (beat_at_frame (pos) - beats.to_double());
3472 }
3473
3474 /** Add the BBT interval op to pos and return the result */
3475 framepos_t
3476 TempoMap::framepos_plus_bbt (framepos_t pos, BBT_Time op) const
3477 {
3478         Glib::Threads::RWLock::ReaderLock lm (lock);
3479
3480         BBT_Time pos_bbt = bbt_at_beat_locked (_metrics, beat_at_frame_locked (_metrics, pos));
3481         pos_bbt.ticks += op.ticks;
3482         if (pos_bbt.ticks >= BBT_Time::ticks_per_beat) {
3483                 ++pos_bbt.beats;
3484                 pos_bbt.ticks -= BBT_Time::ticks_per_beat;
3485         }
3486         pos_bbt.beats += op.beats;
3487         /* the meter in effect will start on the bar */
3488         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();
3489         while (pos_bbt.beats >= divisions_per_bar + 1) {
3490                 ++pos_bbt.bars;
3491                 divisions_per_bar = meter_section_at_beat (beat_at_bbt_locked (_metrics, BBT_Time (pos_bbt.bars + op.bars, 1, 0))).divisions_per_bar();
3492                 pos_bbt.beats -= divisions_per_bar;
3493         }
3494         pos_bbt.bars += op.bars;
3495
3496         return frame_time_locked (_metrics, pos_bbt);
3497 }
3498
3499 /** Count the number of beats that are equivalent to distance when going forward,
3500     starting at pos.
3501 */
3502 Evoral::Beats
3503 TempoMap::framewalk_to_beats (framepos_t pos, framecnt_t distance) const
3504 {
3505         return Evoral::Beats (beat_at_frame (pos + distance) - beat_at_frame (pos));
3506 }
3507
3508 struct bbtcmp {
3509     bool operator() (const BBT_Time& a, const BBT_Time& b) {
3510             return a < b;
3511     }
3512 };
3513
3514 std::ostream&
3515 operator<< (std::ostream& o, const Meter& m) {
3516         return o << m.divisions_per_bar() << '/' << m.note_divisor();
3517 }
3518
3519 std::ostream&
3520 operator<< (std::ostream& o, const Tempo& t) {
3521         return o << t.beats_per_minute() << " 1/" << t.note_type() << "'s per minute";
3522 }
3523
3524 std::ostream&
3525 operator<< (std::ostream& o, const MetricSection& section) {
3526
3527         o << "MetricSection @ " << section.frame() << ' ';
3528
3529         const TempoSection* ts;
3530         const MeterSection* ms;
3531
3532         if ((ts = dynamic_cast<const TempoSection*> (&section)) != 0) {
3533                 o << *((const Tempo*) ts);
3534         } else if ((ms = dynamic_cast<const MeterSection*> (&section)) != 0) {
3535                 o << *((const Meter*) ms);
3536         }
3537
3538         return o;
3539 }