libs/ardour/region.cc

   1 /*
   2     Copyright (C) 2000-2003 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 <iostream>
  21 #include <cmath>
  22 #include <climits>
  23 #include <algorithm>
  24 #include <sstream>
  25
  26 #include <glibmm/thread.h>
  27 #include "pbd/xml++.h"
  28 #include "pbd/stacktrace.h"
  29 #include "pbd/enumwriter.h"
  30
  31 #include "ardour/debug.h"
  32 #include "ardour/region.h"
  33 #include "ardour/playlist.h"
  34 #include "ardour/session.h"
  35 #include "ardour/source.h"
  36 #include "ardour/tempo.h"
  37 #include "ardour/region_factory.h"
  38 #include "ardour/filter.h"
  39 #include "ardour/profile.h"
  40 #include "ardour/utils.h"
  41
  42 #include "i18n.h"
  43
  44 using namespace std;
  45 using namespace ARDOUR;
  46 using namespace PBD;
  47
  48 namespace ARDOUR {
  49         namespace Properties {
  50                 PBD::PropertyDescriptor<bool> muted;
  51                 PBD::PropertyDescriptor<bool> opaque;
  52                 PBD::PropertyDescriptor<bool> locked;
  53                 PBD::PropertyDescriptor<bool> automatic;
  54                 PBD::PropertyDescriptor<bool> whole_file;
  55                 PBD::PropertyDescriptor<bool> import;
  56                 PBD::PropertyDescriptor<bool> external;
  57                 PBD::PropertyDescriptor<bool> sync_marked;
  58                 PBD::PropertyDescriptor<bool> left_of_split;
  59                 PBD::PropertyDescriptor<bool> right_of_split;
  60                 PBD::PropertyDescriptor<bool> hidden;
  61                 PBD::PropertyDescriptor<bool> position_locked;
  62                 PBD::PropertyDescriptor<bool> valid_transients;
  63                 PBD::PropertyDescriptor<framepos_t> start;
  64                 PBD::PropertyDescriptor<framecnt_t> length;
  65                 PBD::PropertyDescriptor<framepos_t> position;
  66                 PBD::PropertyDescriptor<framecnt_t> sync_position;
  67                 PBD::PropertyDescriptor<layer_t> layer;
  68                 PBD::PropertyDescriptor<framepos_t> ancestral_start;
  69                 PBD::PropertyDescriptor<framecnt_t> ancestral_length;
  70                 PBD::PropertyDescriptor<float> stretch;
  71                 PBD::PropertyDescriptor<float> shift;
  72                 PBD::PropertyDescriptor<PositionLockStyle> position_lock_style;
  73         }
  74 }
  75
  76 PBD::Signal2<void,boost::shared_ptr<ARDOUR::Region>,const PropertyChange&> Region::RegionPropertyChanged;
  77
  78 void
  79 Region::make_property_quarks ()
  80 {
  81         Properties::muted.property_id = g_quark_from_static_string (X_("muted"));
  82         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for muted = %1\n",       Properties::muted.property_id));
  83         Properties::opaque.property_id = g_quark_from_static_string (X_("opaque"));
  84         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for opaque = %1\n",      Properties::opaque.property_id));
  85         Properties::locked.property_id = g_quark_from_static_string (X_("locked"));
  86         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for locked = %1\n",      Properties::locked.property_id));
  87         Properties::automatic.property_id = g_quark_from_static_string (X_("automatic"));
  88         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for automatic = %1\n",   Properties::automatic.property_id));
  89         Properties::whole_file.property_id = g_quark_from_static_string (X_("whole-file"));
  90         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for whole-file = %1\n",  Properties::whole_file.property_id));
  91         Properties::import.property_id = g_quark_from_static_string (X_("import"));
  92         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for import = %1\n",      Properties::import.property_id));
  93         Properties::external.property_id = g_quark_from_static_string (X_("external"));
  94         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for external = %1\n",    Properties::external.property_id));
  95         Properties::sync_marked.property_id = g_quark_from_static_string (X_("sync-marked"));
  96         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for sync-marked = %1\n",         Properties::sync_marked.property_id));
  97         Properties::left_of_split.property_id = g_quark_from_static_string (X_("left-of-split"));
  98         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for left-of-split = %1\n",       Properties::left_of_split.property_id));
  99         Properties::right_of_split.property_id = g_quark_from_static_string (X_("right-of-split"));
 100         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for right-of-split = %1\n",      Properties::right_of_split.property_id));
 101         Properties::hidden.property_id = g_quark_from_static_string (X_("hidden"));
 102         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for hidden = %1\n",      Properties::hidden.property_id));
 103         Properties::position_locked.property_id = g_quark_from_static_string (X_("position-locked"));
 104         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for position-locked = %1\n",     Properties::position_locked.property_id));
 105         Properties::valid_transients.property_id = g_quark_from_static_string (X_("valid-transients"));
 106         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for valid-transients = %1\n",    Properties::valid_transients.property_id));
 107         Properties::start.property_id = g_quark_from_static_string (X_("start"));
 108         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for start = %1\n",       Properties::start.property_id));
 109         Properties::length.property_id = g_quark_from_static_string (X_("length"));
 110         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for length = %1\n",      Properties::length.property_id));
 111         Properties::position.property_id = g_quark_from_static_string (X_("position"));
 112         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for position = %1\n",    Properties::position.property_id));
 113         Properties::sync_position.property_id = g_quark_from_static_string (X_("sync-position"));
 114         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for sync-position = %1\n",       Properties::sync_position.property_id));
 115         Properties::layer.property_id = g_quark_from_static_string (X_("layer"));
 116         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for layer = %1\n",       Properties::layer.property_id));
 117         Properties::ancestral_start.property_id = g_quark_from_static_string (X_("ancestral-start"));
 118         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for ancestral-start = %1\n",     Properties::ancestral_start.property_id));
 119         Properties::ancestral_length.property_id = g_quark_from_static_string (X_("ancestral-length"));
 120         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for ancestral-length = %1\n",    Properties::ancestral_length.property_id));
 121         Properties::stretch.property_id = g_quark_from_static_string (X_("stretch"));
 122         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for stretch = %1\n",     Properties::stretch.property_id));
 123         Properties::shift.property_id = g_quark_from_static_string (X_("shift"));
 124         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for shift = %1\n",       Properties::shift.property_id));
 125         Properties::position_lock_style.property_id = g_quark_from_static_string (X_("positional-lock-style"));
 126         DEBUG_TRACE (DEBUG::Properties, string_compose ("quark for position_lock_style = %1\n",         Properties::position_lock_style.property_id));
 127 }
 128
 129 void
 130 Region::register_properties ()
 131 {
 132         _xml_node_name = X_("Region");
 133
 134         add_property (_muted);
 135         add_property (_opaque);
 136         add_property (_locked);
 137         add_property (_automatic);
 138         add_property (_whole_file);
 139         add_property (_import);
 140         add_property (_external);
 141         add_property (_sync_marked);
 142         add_property (_left_of_split);
 143         add_property (_right_of_split);
 144         add_property (_hidden);
 145         add_property (_position_locked);
 146         add_property (_valid_transients);
 147         add_property (_start);
 148         add_property (_length);
 149         add_property (_position);
 150         add_property (_sync_position);
 151         add_property (_layer);
 152         add_property (_ancestral_start);
 153         add_property (_ancestral_length);
 154         add_property (_stretch);
 155         add_property (_shift);
 156         add_property (_position_lock_style);
 157 }
 158
 159 #define REGION_DEFAULT_STATE(s,l) \
 160         _muted (Properties::muted, false)            \
 161         , _opaque (Properties::opaque, true) \
 162         , _locked (Properties::locked, false) \
 163         , _automatic (Properties::automatic, false) \
 164         , _whole_file (Properties::whole_file, false) \
 165         , _import (Properties::import, false) \
 166         , _external (Properties::external, false) \
 167         , _sync_marked (Properties::sync_marked, false) \
 168         , _left_of_split (Properties::left_of_split, false) \
 169         , _right_of_split (Properties::right_of_split, false) \
 170         , _hidden (Properties::hidden, false) \
 171         , _position_locked (Properties::position_locked, false) \
 172         , _valid_transients (Properties::valid_transients, false) \
 173         , _start (Properties::start, (s))       \
 174         , _length (Properties::length, (l))     \
 175         , _position (Properties::position, 0) \
 176         , _sync_position (Properties::sync_position, (s)) \
 177         , _layer (Properties::layer, 0) \
 178         , _ancestral_start (Properties::ancestral_start, (s)) \
 179         , _ancestral_length (Properties::ancestral_length, (l)) \
 180         , _stretch (Properties::stretch, 1.0) \
 181         , _shift (Properties::shift, 1.0) \
 182         , _position_lock_style (Properties::position_lock_style, _type == DataType::AUDIO ? AudioTime : MusicTime)
 183
 184 #define REGION_COPY_STATE(other) \
 185           _muted (other->_muted) \
 186         , _opaque (other->_opaque) \
 187         , _locked (other->_locked) \
 188         , _automatic (other->_automatic) \
 189         , _whole_file (other->_whole_file) \
 190         , _import (other->_import) \
 191         , _external (other->_external) \
 192         , _sync_marked (other->_sync_marked) \
 193         , _left_of_split (other->_left_of_split) \
 194         , _right_of_split (other->_right_of_split) \
 195         , _hidden (other->_hidden) \
 196         , _position_locked (other->_position_locked) \
 197         , _valid_transients (other->_valid_transients) \
 198         , _start(other->_start) \
 199         , _length(other->_length) \
 200         , _position(other->_position) \
 201         , _sync_position(other->_sync_position) \
 202         , _layer (other->_layer) \
 203         , _ancestral_start (other->_ancestral_start) \
 204         , _ancestral_length (other->_ancestral_length) \
 205         , _stretch (other->_stretch) \
 206         , _shift (other->_shift) \
 207         , _position_lock_style (other->_position_lock_style)
 208
 209 /* derived-from-derived constructor (no sources in constructor) */
 210 Region::Region (Session& s, framepos_t start, framecnt_t length, const string& name, DataType type)
 211         : SessionObject(s, name)
 212         , _type(type)
 213         , REGION_DEFAULT_STATE(start,length)
 214         , _last_length (length)
 215         , _last_position (0)
 216         , _first_edit (EditChangesNothing)
 217         , _read_data_count(0)
 218         , _last_layer_op(0)
 219         , _pending_explicit_relayer (false)
 220 {
 221         register_properties ();
 222
 223         /* no sources at this point */
 224 }
 225
 226 /** Basic Region constructor (many sources) */
 227 Region::Region (const SourceList& srcs)
 228         : SessionObject(srcs.front()->session(), "toBeRenamed")
 229         , _type (srcs.front()->type())
 230         , REGION_DEFAULT_STATE(0,0)
 231         , _last_length (0)
 232         , _last_position (0)
 233         , _first_edit (EditChangesNothing)
 234         , _read_data_count(0)
 235         , _last_layer_op (0)
 236         , _pending_explicit_relayer (false)
 237 {
 238         register_properties ();
 239
 240         _type = srcs.front()->type();
 241
 242         use_sources (srcs);
 243
 244         assert(_sources.size() > 0);
 245         assert (_type == srcs.front()->type());
 246 }
 247
 248 /** Create a new Region from part of an existing one, starting at one of two places:
 249
 250     if @param offset_relative is true, then the start within @param other is given by @param offset
 251     (i.e. relative to the start of @param other's sources, the start is @param offset + @param other.start()
 252
 253     if @param offset_relative is false, then the start within the source is given @param offset.
 254 */
 255 Region::Region (boost::shared_ptr<const Region> other, frameoffset_t offset, bool offset_relative)
 256         : SessionObject(other->session(), other->name())
 257         , _type (other->data_type())
 258         , REGION_COPY_STATE (other)
 259         , _last_length (other->_last_length)
 260         , _last_position(other->_last_position) \
 261         , _first_edit (EditChangesNothing)
 262         , _read_data_count(0)
 263         , _last_layer_op (0)
 264         , _pending_explicit_relayer (false)
 265
 266 {
 267         register_properties ();
 268
 269         /* override state that may have been incorrectly inherited from the other region
 270          */
 271
 272         _position = 0;
 273         _locked = false;
 274         _whole_file = false;
 275         _hidden = false;
 276
 277         use_sources (other->_sources);
 278
 279         if (!offset_relative) {
 280
 281                 /* not sure why we do this, but its a hangover from ardour before
 282                    property lists. this would be nice to remove.
 283                 */
 284
 285                 _position_lock_style = other->_position_lock_style;
 286                 _first_edit = other->_first_edit;
 287
 288                 if (offset == 0) {
 289
 290                         _start = 0;
 291
 292                         /* sync pos is relative to start of file. our start-in-file is now zero,
 293                            so set our sync position to whatever the the difference between
 294                            _start and _sync_pos was in the other region.
 295
 296                            result is that our new sync pos points to the same point in our source(s)
 297                            as the sync in the other region did in its source(s).
 298
 299                            since we start at zero in our source(s), it is not possible to use a sync point that
 300                            is before the start. reset it to _start if that was true in the other region.
 301                         */
 302
 303                         if (other->sync_marked()) {
 304                                 if (other->_start < other->_sync_position) {
 305                                         /* sync pos was after the start point of the other region */
 306                                         _sync_position = other->_sync_position - other->_start;
 307                                 } else {
 308                                         /* sync pos was before the start point of the other region. not possible here. */
 309                                         _sync_marked = false;
 310                                         _sync_position = _start;
 311                                 }
 312                         } else {
 313                                 _sync_marked = false;
 314                                 _sync_position = _start;
 315                         }
 316                 } else {
 317                         /* XXX do something else ! */
 318                         fatal << string_compose (_("programming error: %1"), X_("Region+offset constructor used with illegal combination of offset+relative"))
 319                               << endmsg;
 320                         /*NOTREACHED*/
 321                 }
 322
 323         } else {
 324
 325                 _start = other->_start + offset;
 326
 327                 /* if the other region had a distinct sync point
 328                    set, then continue to use it as best we can.
 329                    otherwise, reset sync point back to start.
 330                 */
 331
 332                 if (other->sync_marked()) {
 333                         if (other->_sync_position < _start) {
 334                                 _sync_marked = false;
 335                                 _sync_position = _start;
 336                 } else {
 337                                 _sync_position = other->_sync_position;
 338                         }
 339                 } else {
 340                         _sync_marked = false;
 341                         _sync_position = _start;
 342                 }
 343         }
 344
 345         if (Profile->get_sae()) {
 346                 /* reset sync point to start if its ended up
 347                    outside region bounds.
 348                 */
 349
 350                 if (_sync_position < _start || _sync_position >= _start + _length) {
 351                         _sync_marked = false;
 352                         _sync_position = _start;
 353                 }
 354         }
 355
 356         assert (_type == other->data_type());
 357 }
 358
 359 /** Create a copy of @param other but with different sources. Used by filters */
 360 Region::Region (boost::shared_ptr<const Region> other, const SourceList& srcs)
 361         : SessionObject (other->session(), other->name())
 362         , _type (srcs.front()->type())
 363         , REGION_COPY_STATE (other)
 364         , _last_length (other->_last_length)
 365         , _last_position (other->_last_position)
 366         , _first_edit (EditChangesID)
 367         , _read_data_count (0)
 368         , _last_layer_op (other->_last_layer_op)
 369         , _pending_explicit_relayer (false)
 370 {
 371         register_properties ();
 372
 373         _locked = false;
 374         _position_locked = false;
 375
 376         other->_first_edit = EditChangesName;
 377
 378         if (other->_extra_xml) {
 379                 _extra_xml = new XMLNode (*other->_extra_xml);
 380         } else {
 381                 _extra_xml = 0;
 382         }
 383
 384         use_sources (srcs);
 385         assert(_sources.size() > 0);
 386 }
 387
 388 /** Simple "copy" constructor */
 389 Region::Region (boost::shared_ptr<const Region> other)
 390         : SessionObject(other->session(), other->name())
 391         , _type(other->data_type())
 392         , REGION_COPY_STATE (other)
 393         , _last_length (other->_last_length)
 394         , _last_position (other->_last_position)
 395         , _first_edit (EditChangesID)
 396         , _read_data_count(0)
 397         , _last_layer_op(other->_last_layer_op)
 398         , _pending_explicit_relayer (false)
 399 {
 400         register_properties ();
 401
 402         _locked = false;
 403         _position_locked = false;
 404
 405         other->_first_edit = EditChangesName;
 406
 407         if (other->_extra_xml) {
 408                 _extra_xml = new XMLNode (*other->_extra_xml);
 409         } else {
 410                 _extra_xml = 0;
 411         }
 412
 413         use_sources (other->_sources);
 414         assert(_sources.size() > 0);
 415 }
 416
 417 Region::~Region ()
 418 {
 419         DEBUG_TRACE (DEBUG::Destruction, string_compose ("Region %1 destructor @ %2\n", _name, this));
 420         drop_sources ();
 421 }
 422
 423 void
 424 Region::set_playlist (boost::weak_ptr<Playlist> wpl)
 425 {
 426         _playlist = wpl.lock();
 427 }
 428
 429 bool
 430 Region::set_name (const std::string& str)
 431 {
 432         if (_name != str) {
 433                 SessionObject::set_name(str); // EMIT SIGNAL NameChanged()
 434                 assert(_name == str);
 435                 send_change (Properties::name);
 436         }
 437
 438         return true;
 439 }
 440
 441 void
 442 Region::set_length (framecnt_t len, void */*src*/)
 443 {
 444         //cerr << "Region::set_length() len = " << len << endl;
 445         if (locked()) {
 446                 return;
 447         }
 448
 449         if (_length != len && len != 0) {
 450
 451                 /* check that the current _position wouldn't make the new
 452                    length impossible.
 453                 */
 454
 455                 if (max_frames - len < _position) {
 456                         return;
 457                 }
 458
 459                 if (!verify_length (len)) {
 460                         return;
 461                 }
 462
 463
 464                 _last_length = _length;
 465                 _length = len;
 466                 _whole_file = false;
 467                 first_edit ();
 468                 maybe_uncopy ();
 469                 invalidate_transients ();
 470
 471                 if (!property_changes_suspended()) {
 472                         recompute_at_end ();
 473                 }
 474
 475                 send_change (Properties::length);
 476         }
 477 }
 478
 479 void
 480 Region::maybe_uncopy ()
 481 {
 482         /* this does nothing but marked a semantic moment once upon a time */
 483 }
 484
 485 void
 486 Region::first_edit ()
 487 {
 488         boost::shared_ptr<Playlist> pl (playlist());
 489
 490         if (_first_edit != EditChangesNothing && pl) {
 491
 492                 _name = RegionFactory::new_region_name (_name);
 493                 _first_edit = EditChangesNothing;
 494
 495                 send_change (Properties::name);
 496                 RegionFactory::CheckNewRegion (shared_from_this());
 497         }
 498 }
 499
 500 bool
 501 Region::at_natural_position () const
 502 {
 503         boost::shared_ptr<Playlist> pl (playlist());
 504
 505         if (!pl) {
 506                 return false;
 507         }
 508
 509         boost::shared_ptr<Region> whole_file_region = get_parent();
 510
 511         if (whole_file_region) {
 512                 if (_position == whole_file_region->position() + _start) {
 513                         return true;
 514                 }
 515         }
 516
 517         return false;
 518 }
 519
 520 void
 521 Region::move_to_natural_position (void *src)
 522 {
 523         boost::shared_ptr<Playlist> pl (playlist());
 524
 525         if (!pl) {
 526                 return;
 527         }
 528
 529         boost::shared_ptr<Region> whole_file_region = get_parent();
 530
 531         if (whole_file_region) {
 532                 set_position (whole_file_region->position() + _start, src);
 533         }
 534 }
 535
 536 void
 537 Region::special_set_position (framepos_t pos)
 538 {
 539         /* this is used when creating a whole file region as
 540            a way to store its "natural" or "captured" position.
 541         */
 542
 543         _position = _position;
 544         _position = pos;
 545 }
 546
 547 void
 548 Region::set_position_lock_style (PositionLockStyle ps)
 549 {
 550         if (_position_lock_style != ps) {
 551
 552                 boost::shared_ptr<Playlist> pl (playlist());
 553
 554                 if (!pl) {
 555                         return;
 556                 }
 557
 558                 _position_lock_style = ps;
 559
 560                 if (_position_lock_style == MusicTime) {
 561                         _session.tempo_map().bbt_time (_position, _bbt_time);
 562                 }
 563
 564                 send_change (Properties::position_lock_style);
 565         }
 566 }
 567
 568 void
 569 Region::update_position_after_tempo_map_change ()
 570 {
 571         boost::shared_ptr<Playlist> pl (playlist());
 572
 573         if (!pl || _position_lock_style != MusicTime) {
 574                 return;
 575         }
 576
 577         TempoMap& map (_session.tempo_map());
 578         framepos_t pos = map.frame_time (_bbt_time);
 579         set_position_internal (pos, false);
 580 }
 581
 582 void
 583 Region::set_position (framepos_t pos, void* /*src*/)
 584 {
 585         if (!can_move()) {
 586                 return;
 587         }
 588
 589         set_position_internal (pos, true);
 590 }
 591
 592 void
 593 Region::set_position_internal (framepos_t pos, bool allow_bbt_recompute)
 594 {
 595         if (_position != pos) {
 596                 _last_position = _position;
 597                 _position = pos;
 598
 599                 /* check that the new _position wouldn't make the current
 600                    length impossible - if so, change the length.
 601
 602                    XXX is this the right thing to do?
 603                 */
 604
 605                 if (max_frames - _length < _position) {
 606                         _last_length = _length;
 607                         _length = max_frames - _position;
 608                 }
 609
 610                 if (allow_bbt_recompute) {
 611                         recompute_position_from_lock_style ();
 612                 }
 613
 614                 //invalidate_transients ();
 615         }
 616
 617         /* do this even if the position is the same. this helps out
 618            a GUI that has moved its representation already.
 619         */
 620         send_change (Properties::position);
 621 }
 622
 623 void
 624 Region::set_position_on_top (framepos_t pos, void* /*src*/)
 625 {
 626         if (locked()) {
 627                 return;
 628         }
 629
 630         if (_position != pos) {
 631                 _last_position = _position;
 632                 _position = pos;
 633         }
 634
 635         boost::shared_ptr<Playlist> pl (playlist());
 636
 637         if (pl) {
 638                 pl->raise_region_to_top (shared_from_this ());
 639         }
 640
 641         /* do this even if the position is the same. this helps out
 642            a GUI that has moved its representation already.
 643         */
 644
 645         send_change (Properties::position);
 646 }
 647
 648 void
 649 Region::recompute_position_from_lock_style ()
 650 {
 651         if (_position_lock_style == MusicTime) {
 652                 _session.tempo_map().bbt_time (_position, _bbt_time);
 653         }
 654 }
 655
 656 void
 657 Region::nudge_position (frameoffset_t n, void* /*src*/)
 658 {
 659         if (locked()) {
 660                 return;
 661         }
 662
 663         if (n == 0) {
 664                 return;
 665         }
 666
 667         _last_position = _position;
 668
 669         if (n > 0) {
 670                 if (_position > max_frames - n) {
 671                         _position = max_frames;
 672                 } else {
 673                         _position += n;
 674                 }
 675         } else {
 676                 if (_position < -n) {
 677                         _position = 0;
 678                 } else {
 679                         _position += n;
 680                 }
 681         }
 682
 683         send_change (Properties::position);
 684 }
 685
 686 void
 687 Region::set_ancestral_data (framepos_t s, framecnt_t l, float st, float sh)
 688 {
 689         _ancestral_length = l;
 690         _ancestral_start = s;
 691         _stretch = st;
 692         _shift = sh;
 693 }
 694
 695 void
 696 Region::set_start (framepos_t pos, void* /*src*/)
 697 {
 698         if (locked() || position_locked()) {
 699                 return;
 700         }
 701         /* This just sets the start, nothing else. It effectively shifts
 702            the contents of the Region within the overall extent of the Source,
 703            without changing the Region's position or length
 704         */
 705
 706         if (_start != pos) {
 707
 708                 if (!verify_start (pos)) {
 709                         return;
 710                 }
 711
 712                 _start = pos;
 713                 _whole_file = false;
 714                 first_edit ();
 715                 invalidate_transients ();
 716
 717                 send_change (Properties::start);
 718         }
 719 }
 720
 721 void
 722 Region::trim_start (framepos_t new_position, void */*src*/)
 723 {
 724         if (locked() || position_locked()) {
 725                 return;
 726         }
 727         framepos_t new_start;
 728         frameoffset_t start_shift;
 729
 730         if (new_position > _position) {
 731                 start_shift = new_position - _position;
 732         } else {
 733                 start_shift = -(_position - new_position);
 734         }
 735
 736         if (start_shift > 0) {
 737
 738                 if (_start > max_frames - start_shift) {
 739                         new_start = max_frames;
 740                 } else {
 741                         new_start = _start + start_shift;
 742                 }
 743
 744                 if (!verify_start (new_start)) {
 745                         return;
 746                 }
 747
 748         } else if (start_shift < 0) {
 749
 750                 if (_start < -start_shift) {
 751                         new_start = 0;
 752                 } else {
 753                         new_start = _start + start_shift;
 754                 }
 755         } else {
 756                 return;
 757         }
 758
 759         if (new_start == _start) {
 760                 return;
 761         }
 762
 763         _start = new_start;
 764         _whole_file = false;
 765         first_edit ();
 766
 767         send_change (Properties::start);
 768 }
 769
 770 void
 771 Region::trim_front (framepos_t new_position, void *src)
 772 {
 773         modify_front (new_position, false, src);
 774 }
 775
 776 void
 777 Region::cut_front (nframes_t new_position, void *src)
 778 {
 779         modify_front (new_position, true, src);
 780 }
 781
 782 void
 783 Region::cut_end (nframes_t new_endpoint, void *src)
 784 {
 785         modify_end (new_endpoint, true, src);
 786 }
 787
 788 void
 789 Region::modify_front (nframes_t new_position, bool reset_fade, void *src)
 790 {
 791         if (locked()) {
 792                 return;
 793         }
 794
 795         nframes_t end = last_frame();
 796         nframes_t source_zero;
 797
 798         if (_position > _start) {
 799                 source_zero = _position - _start;
 800         } else {
 801                 source_zero = 0; // its actually negative, but this will work for us
 802         }
 803
 804         if (new_position < end) { /* can't trim it zero or negative length */
 805
 806                 nframes_t newlen = 0;
 807                 nframes64_t delta = 0;
 808
 809                 /* can't trim it back passed where source position zero is located */
 810
 811                 new_position = max (new_position, source_zero);
 812
 813                 if (new_position > _position) {
 814                         newlen = _length - (new_position - _position);
 815                         delta = -1 * (new_position - _position);
 816                 } else {
 817                         newlen = _length + (_position - new_position);
 818                         delta = _position - new_position;
 819                 }
 820
 821                 trim_to_internal (new_position, newlen, src);
 822
 823                 if (reset_fade) {
 824                         _right_of_split = true;
 825                 }
 826
 827                 if (!property_changes_suspended()) {
 828                         recompute_at_start ();
 829                 }
 830
 831                 if (_transients.size() > 0){
 832                         adjust_transients(delta);
 833                 }
 834         }
 835 }
 836
 837 void
 838 Region::modify_end (nframes_t new_endpoint, bool reset_fade, void *src)
 839 {
 840         if (locked()) {
 841                 return;
 842         }
 843
 844         if (new_endpoint > _position) {
 845                 trim_to_internal (_position, new_endpoint - _position +1, this);
 846                 if (reset_fade) {
 847                         _left_of_split = true;
 848                 }
 849                 if (!property_changes_suspended()) {
 850                         recompute_at_end ();
 851                 }
 852         }
 853 }
 854
 855 /** @param new_endpoint New region end point, such that, for example,
 856  *  a region at 0 of length 10 has an endpoint of 9.
 857  */
 858
 859 void
 860 Region::trim_end (framepos_t new_endpoint, void* src)
 861 {
 862         modify_end (new_endpoint, false, src);
 863 }
 864
 865 void
 866 Region::trim_to (framepos_t position, framecnt_t length, void *src)
 867 {
 868         if (locked()) {
 869                 return;
 870         }
 871
 872         trim_to_internal (position, length, src);
 873
 874         if (!property_changes_suspended()) {
 875                 recompute_at_start ();
 876                 recompute_at_end ();
 877         }
 878 }
 879
 880 void
 881 Region::trim_to_internal (framepos_t position, framecnt_t length, void */*src*/)
 882 {
 883         frameoffset_t start_shift;
 884         framepos_t new_start;
 885
 886         if (locked()) {
 887                 return;
 888         }
 889
 890         if (position > _position) {
 891                 start_shift = position - _position;
 892         } else {
 893                 start_shift = -(_position - position);
 894         }
 895
 896         if (start_shift > 0) {
 897
 898                 if (_start > max_frames - start_shift) {
 899                         new_start = max_frames;
 900                 } else {
 901                         new_start = _start + start_shift;
 902                 }
 903
 904         } else if (start_shift < 0) {
 905
 906                 if (_start < -start_shift) {
 907                         new_start = 0;
 908                 } else {
 909                         new_start = _start + start_shift;
 910                 }
 911
 912         } else {
 913                 new_start = _start;
 914         }
 915
 916         if (!verify_start_and_length (new_start, length)) {
 917                 return;
 918         }
 919
 920         PropertyChange what_changed;
 921
 922         if (_start != new_start) {
 923                 _start = new_start;
 924                 what_changed.add (Properties::start);
 925         }
 926         if (_length != length) {
 927                 if (!property_changes_suspended()) {
 928                         _last_length = _length;
 929                 }
 930                 _length = length;
 931                 what_changed.add (Properties::length);
 932         }
 933         if (_position != position) {
 934                 if (!property_changes_suspended()) {
 935                         _last_position = _position;
 936                 }
 937                 _position = position;
 938                 what_changed.add (Properties::position);
 939         }
 940
 941         _whole_file = false;
 942
 943         PropertyChange start_and_length;
 944
 945         start_and_length.add (Properties::start);
 946         start_and_length.add (Properties::length);
 947
 948         if (what_changed.contains (start_and_length)) {
 949                 first_edit ();
 950         }
 951
 952         if (!what_changed.empty()) {
 953                 send_change (what_changed);
 954         }
 955 }
 956
 957 void
 958 Region::set_hidden (bool yn)
 959 {
 960         if (hidden() != yn) {
 961                 _hidden = yn;
 962                 send_change (Properties::hidden);
 963         }
 964 }
 965
 966 void
 967 Region::set_whole_file (bool yn)
 968 {
 969         _whole_file = yn;
 970         /* no change signal */
 971 }
 972
 973 void
 974 Region::set_automatic (bool yn)
 975 {
 976         _automatic = yn;
 977         /* no change signal */
 978 }
 979
 980 void
 981 Region::set_muted (bool yn)
 982 {
 983         if (muted() != yn) {
 984                 _muted = yn;
 985                 send_change (Properties::muted);
 986         }
 987 }
 988
 989 void
 990 Region::set_opaque (bool yn)
 991 {
 992         if (opaque() != yn) {
 993                 _opaque = yn;
 994                 send_change (Properties::opaque);
 995         }
 996 }
 997
 998 void
 999 Region::set_locked (bool yn)
1000 {
1001         if (locked() != yn) {
1002                 _locked = yn;
1003                 send_change (Properties::locked);
1004         }
1005 }
1006
1007 void
1008 Region::set_position_locked (bool yn)
1009 {
1010         if (position_locked() != yn) {
1011                 _position_locked = yn;
1012                 send_change (Properties::locked);
1013         }
1014 }
1015
1016 void
1017 Region::set_sync_position (framepos_t absolute_pos)
1018 {
1019         framepos_t const file_pos = _start + (absolute_pos - _position);
1020
1021         if (file_pos != _sync_position) {
1022                 _sync_marked = true;
1023                 _sync_position = file_pos;
1024                 if (!property_changes_suspended()) {
1025                         maybe_uncopy ();
1026                 }
1027                 send_change (Properties::sync_position);
1028         }
1029 }
1030
1031 void
1032 Region::clear_sync_position ()
1033 {
1034         if (sync_marked()) {
1035                 _sync_marked = false;
1036                 if (!property_changes_suspended()) {
1037                         maybe_uncopy ();
1038                 }
1039                 send_change (Properties::sync_position);
1040         }
1041 }
1042
1043 framepos_t
1044 Region::sync_offset (int& dir) const
1045 {
1046         /* returns the sync point relative the first frame of the region */
1047
1048         if (sync_marked()) {
1049                 if (_sync_position > _start) {
1050                         dir = 1;
1051                         return _sync_position - _start;
1052                 } else {
1053                         dir = -1;
1054                         return _start - _sync_position;
1055                 }
1056         } else {
1057                 dir = 0;
1058                 return 0;
1059         }
1060 }
1061
1062 framepos_t
1063 Region::adjust_to_sync (framepos_t pos) const
1064 {
1065         int sync_dir;
1066         frameoffset_t offset = sync_offset (sync_dir);
1067
1068         // cerr << "adjusting pos = " << pos << " to sync at " << _sync_position << " offset = " << offset << " with dir = " << sync_dir << endl;
1069
1070         if (sync_dir > 0) {
1071                 if (pos > offset) {
1072                         pos -= offset;
1073                 } else {
1074                         pos = 0;
1075                 }
1076         } else {
1077                 if (max_frames - pos > offset) {
1078                         pos += offset;
1079                 }
1080         }
1081
1082         return pos;
1083 }
1084
1085 framepos_t
1086 Region::sync_position() const
1087 {
1088         if (sync_marked()) {
1089                 return _sync_position;
1090         } else {
1091                 return _start;
1092         }
1093 }
1094
1095 void
1096 Region::raise ()
1097 {
1098         boost::shared_ptr<Playlist> pl (playlist());
1099         if (pl) {
1100                 pl->raise_region (shared_from_this ());
1101         }
1102 }
1103
1104 void
1105 Region::lower ()
1106 {
1107         boost::shared_ptr<Playlist> pl (playlist());
1108         if (pl) {
1109                 pl->lower_region (shared_from_this ());
1110         }
1111 }
1112
1113
1114 void
1115 Region::raise_to_top ()
1116 {
1117         boost::shared_ptr<Playlist> pl (playlist());
1118         if (pl) {
1119                 pl->raise_region_to_top (shared_from_this());
1120         }
1121 }
1122
1123 void
1124 Region::lower_to_bottom ()
1125 {
1126         boost::shared_ptr<Playlist> pl (playlist());
1127         if (pl) {
1128                 pl->lower_region_to_bottom (shared_from_this());
1129         }
1130 }
1131
1132 void
1133 Region::set_layer (layer_t l)
1134 {
1135         if (_layer != l) {
1136                 _layer = l;
1137
1138                 send_change (Properties::layer);
1139         }
1140 }
1141
1142 XMLNode&
1143 Region::state (bool full)
1144 {
1145         XMLNode *node = new XMLNode ("Region");
1146         char buf[64];
1147         char buf2[64];
1148         LocaleGuard lg (X_("POSIX"));
1149         const char* fe = NULL;
1150
1151         add_properties (*node);
1152
1153         _id.print (buf, sizeof (buf));
1154         node->add_property ("id", buf);
1155         node->add_property ("type", _type.to_string());
1156
1157         switch (_first_edit) {
1158         case EditChangesNothing:
1159                 fe = X_("nothing");
1160                 break;
1161         case EditChangesName:
1162                 fe = X_("name");
1163                 break;
1164         case EditChangesID:
1165                 fe = X_("id");
1166                 break;
1167         default: /* should be unreachable but makes g++ happy */
1168                 fe = X_("nothing");
1169                 break;
1170         }
1171
1172         node->add_property ("first-edit", fe);
1173
1174         /* note: flags are stored by derived classes */
1175
1176         if (_position_lock_style != AudioTime) {
1177                 stringstream str;
1178                 str << _bbt_time;
1179                 node->add_property ("bbt-position", str.str());
1180         }
1181
1182         for (uint32_t n=0; n < _sources.size(); ++n) {
1183                 snprintf (buf2, sizeof(buf2), "source-%d", n);
1184                 _sources[n]->id().print (buf, sizeof(buf));
1185                 node->add_property (buf2, buf);
1186         }
1187
1188         for (uint32_t n=0; n < _master_sources.size(); ++n) {
1189                 snprintf (buf2, sizeof(buf2), "master-source-%d", n);
1190                 _master_sources[n]->id().print (buf, sizeof (buf));
1191                 node->add_property (buf2, buf);
1192         }
1193
1194         if (full && _extra_xml) {
1195                 node->add_child_copy (*_extra_xml);
1196         }
1197
1198         return *node;
1199 }
1200
1201 XMLNode&
1202 Region::get_state ()
1203 {
1204         return state (true);
1205 }
1206
1207 int
1208 Region::set_state (const XMLNode& node, int version)
1209 {
1210         PropertyChange what_changed;
1211         return _set_state (node, version, what_changed, true);
1212 }
1213
1214 int
1215 Region::_set_state (const XMLNode& node, int version, PropertyChange& what_changed, bool send)
1216 {
1217         const XMLProperty* prop;
1218
1219         what_changed = set_properties (node);
1220
1221         if ((prop = node.property (X_("id")))) {
1222                 _id = prop->value();
1223         }
1224
1225         if (_position_lock_style == MusicTime) {
1226                 if ((prop = node.property ("bbt-position")) == 0) {
1227                         /* missing BBT info, revert to audio time locking */
1228                         _position_lock_style = AudioTime;
1229                 } else {
1230                         if (sscanf (prop->value().c_str(), "%d|%d|%d",
1231                                     &_bbt_time.bars,
1232                                     &_bbt_time.beats,
1233                                     &_bbt_time.ticks) != 3) {
1234                                 _position_lock_style = AudioTime;
1235                         }
1236                 }
1237         }
1238
1239         /* fix problems with old sessions corrupted by impossible
1240            values for _stretch or _shift
1241         */
1242         if (_stretch == 0.0f) {
1243                 _stretch = 1.0f;
1244         }
1245
1246         if (_shift == 0.0f) {
1247                 _shift = 1.0f;
1248         }
1249
1250         const XMLNodeList& nlist = node.children();
1251
1252         for (XMLNodeConstIterator niter = nlist.begin(); niter != nlist.end(); ++niter) {
1253
1254                 XMLNode *child;
1255
1256                 child = (*niter);
1257
1258                 if (child->name () == "Extra") {
1259                         delete _extra_xml;
1260                         _extra_xml = new XMLNode (*child);
1261                         break;
1262                 }
1263         }
1264
1265         if (send) {
1266                 send_change (what_changed);
1267         }
1268
1269         /* Quick fix for 2.x sessions when region is muted */
1270         if ((prop = node.property (X_("flags")))) {
1271                 if (string::npos != prop->value().find("Muted")){
1272                         set_muted (true);
1273                 }
1274         }
1275
1276
1277         return 0;
1278 }
1279
1280 void
1281 Region::suspend_property_changes ()
1282 {
1283         Stateful::suspend_property_changes ();
1284         _last_length = _length;
1285         _last_position = _position;
1286 }
1287
1288 void
1289 Region::mid_thaw (const PropertyChange& what_changed)
1290 {
1291         if (what_changed.contains (Properties::length)) {
1292                 if (what_changed.contains (Properties::position)) {
1293                         recompute_at_start ();
1294                 }
1295                 recompute_at_end ();
1296         }
1297 }
1298
1299 void
1300 Region::send_change (const PropertyChange& what_changed)
1301 {
1302         if (what_changed.empty()) {
1303                 return;
1304         }
1305
1306         Stateful::send_change (what_changed);
1307
1308         if (!_no_property_changes) {
1309
1310                 /* Try and send a shared_pointer unless this is part of the constructor.
1311                    If so, do nothing.
1312                 */
1313
1314                 try {
1315                         boost::shared_ptr<Region> rptr = shared_from_this();
1316                         RegionPropertyChanged (rptr, what_changed);
1317                 } catch (...) {
1318                         /* no shared_ptr available, relax; */
1319                 }
1320         }
1321 }
1322
1323 void
1324 Region::set_last_layer_op (uint64_t when)
1325 {
1326         _last_layer_op = when;
1327 }
1328
1329 bool
1330 Region::overlap_equivalent (boost::shared_ptr<const Region> other) const
1331 {
1332         return coverage (other->first_frame(), other->last_frame()) != OverlapNone;
1333 }
1334
1335 bool
1336 Region::equivalent (boost::shared_ptr<const Region> other) const
1337 {
1338         return _start == other->_start &&
1339                 _position == other->_position &&
1340                 _length == other->_length;
1341 }
1342
1343 bool
1344 Region::size_equivalent (boost::shared_ptr<const Region> other) const
1345 {
1346         return _start == other->_start &&
1347                 _length == other->_length;
1348 }
1349
1350 bool
1351 Region::region_list_equivalent (boost::shared_ptr<const Region> other) const
1352 {
1353         return size_equivalent (other) && source_equivalent (other) && _name == other->_name;
1354 }
1355
1356 void
1357 Region::source_deleted (boost::weak_ptr<Source>)
1358 {
1359         drop_sources ();
1360
1361         if (!_session.deletion_in_progress()) {
1362                 /* this is a very special case: at least one of the region's
1363                    sources has bee deleted, so invalidate all references to
1364                    ourselves. Do NOT do this during session deletion, because
1365                    then we run the risk that this will actually result
1366                    in this object being deleted (as refcnt goes to zero)
1367                    while emitting DropReferences.
1368                 */
1369
1370                 drop_references ();
1371         }
1372 }
1373
1374 vector<string>
1375 Region::master_source_names ()
1376 {
1377         SourceList::iterator i;
1378
1379         vector<string> names;
1380         for (i = _master_sources.begin(); i != _master_sources.end(); ++i) {
1381                 names.push_back((*i)->name());
1382         }
1383
1384         return names;
1385 }
1386
1387 void
1388 Region::set_master_sources (const SourceList& srcs)
1389 {
1390         for (SourceList::const_iterator i = _master_sources.begin (); i != _master_sources.end(); ++i) {
1391                 cerr << name() << " " << id() << " DEC M SMS\n";
1392                 (*i)->dec_use_count ();
1393         }
1394
1395         _master_sources = srcs;
1396         assert (_sources.size() == _master_sources.size());
1397
1398         for (SourceList::const_iterator i = _master_sources.begin (); i != _master_sources.end(); ++i) {
1399                 (*i)->inc_use_count ();
1400         }
1401 }
1402
1403 bool
1404 Region::source_equivalent (boost::shared_ptr<const Region> other) const
1405 {
1406         if (!other)
1407                 return false;
1408
1409         SourceList::const_iterator i;
1410         SourceList::const_iterator io;
1411
1412         for (i = _sources.begin(), io = other->_sources.begin(); i != _sources.end() && io != other->_sources.end(); ++i, ++io) {
1413                 if ((*i)->id() != (*io)->id()) {
1414                         return false;
1415                 }
1416         }
1417
1418         for (i = _master_sources.begin(), io = other->_master_sources.begin(); i != _master_sources.end() && io != other->_master_sources.end(); ++i, ++io) {
1419                 if ((*i)->id() != (*io)->id()) {
1420                         return false;
1421                 }
1422         }
1423
1424         return true;
1425 }
1426
1427 bool
1428 Region::uses_source (boost::shared_ptr<const Source> source) const
1429 {
1430         for (SourceList::const_iterator i = _sources.begin(); i != _sources.end(); ++i) {
1431                 if (*i == source) {
1432                         return true;
1433                 }
1434         }
1435         return false;
1436 }
1437
1438 sframes_t
1439 Region::source_length(uint32_t n) const
1440 {
1441         assert (n < _sources.size());
1442         return _sources[n]->length(_position - _start);
1443 }
1444
1445 bool
1446 Region::verify_length (framecnt_t len)
1447 {
1448         if (source() && (source()->destructive() || source()->length_mutable())) {
1449                 return true;
1450         }
1451
1452         framecnt_t maxlen = 0;
1453
1454         for (uint32_t n = 0; n < _sources.size(); ++n) {
1455                 maxlen = max (maxlen, source_length(n) - _start);
1456         }
1457
1458         len = min (len, maxlen);
1459
1460         return true;
1461 }
1462
1463 bool
1464 Region::verify_start_and_length (framepos_t new_start, framecnt_t& new_length)
1465 {
1466         if (source() && (source()->destructive() || source()->length_mutable())) {
1467                 return true;
1468         }
1469
1470         framecnt_t maxlen = 0;
1471
1472         for (uint32_t n = 0; n < _sources.size(); ++n) {
1473                 maxlen = max (maxlen, source_length(n) - new_start);
1474         }
1475
1476         new_length = min (new_length, maxlen);
1477
1478         return true;
1479 }
1480
1481 bool
1482 Region::verify_start (framepos_t pos)
1483 {
1484         if (source() && (source()->destructive() || source()->length_mutable())) {
1485                 return true;
1486         }
1487
1488         for (uint32_t n = 0; n < _sources.size(); ++n) {
1489                 if (pos > source_length(n) - _length) {
1490                         return false;
1491                 }
1492         }
1493         return true;
1494 }
1495
1496 bool
1497 Region::verify_start_mutable (framepos_t& new_start)
1498 {
1499         if (source() && (source()->destructive() || source()->length_mutable())) {
1500                 return true;
1501         }
1502
1503         for (uint32_t n = 0; n < _sources.size(); ++n) {
1504                 if (new_start > source_length(n) - _length) {
1505                         new_start = source_length(n) - _length;
1506                 }
1507         }
1508         return true;
1509 }
1510
1511 boost::shared_ptr<Region>
1512 Region::get_parent() const
1513 {
1514         boost::shared_ptr<Playlist> pl (playlist());
1515
1516         if (pl) {
1517                 boost::shared_ptr<Region> r;
1518                 boost::shared_ptr<Region const> grrr2 = boost::dynamic_pointer_cast<Region const> (shared_from_this());
1519
1520                 if (grrr2 && (r = _session.find_whole_file_parent (grrr2))) {
1521                         return boost::static_pointer_cast<Region> (r);
1522                 }
1523         }
1524
1525         return boost::shared_ptr<Region>();
1526 }
1527
1528 int
1529 Region::apply (Filter& filter)
1530 {
1531         return filter.run (shared_from_this());
1532 }
1533
1534
1535 void
1536 Region::invalidate_transients ()
1537 {
1538         _valid_transients = false;
1539         _transients.clear ();
1540
1541         send_change (PropertyChange (Properties::valid_transients));
1542 }
1543
1544 void
1545 Region::drop_sources ()
1546 {
1547         for (SourceList::const_iterator i = _sources.begin (); i != _sources.end(); ++i) {
1548                 (*i)->dec_use_count ();
1549         }
1550
1551         _sources.clear ();
1552
1553         for (SourceList::const_iterator i = _master_sources.begin (); i != _master_sources.end(); ++i) {
1554                 (*i)->dec_use_count ();
1555         }
1556
1557         _master_sources.clear ();
1558 }
1559
1560 void
1561 Region::use_sources (SourceList const & s)
1562 {
1563         set<boost::shared_ptr<Source> > unique_srcs;
1564
1565         for (SourceList::const_iterator i = s.begin (); i != s.end(); ++i) {
1566
1567                 _sources.push_back (*i);
1568                 (*i)->inc_use_count ();
1569                 _master_sources.push_back (*i);
1570                 (*i)->inc_use_count ();
1571
1572                 /* connect only once to DropReferences, even if sources are replicated
1573                  */
1574
1575                 if (unique_srcs.find (*i) == unique_srcs.end ()) {
1576                         unique_srcs.insert (*i);
1577                         (*i)->DropReferences.connect_same_thread (*this, boost::bind (&Region::source_deleted, this, boost::weak_ptr<Source>(*i)));
1578                 }
1579         }
1580 }
1581
1582 PropertyList*
1583 Region::property_factory (const XMLNode& history_node) const
1584 {
1585         PropertyList* prop_list = new PropertyList;
1586
1587         for (OwnedPropertyList::const_iterator i = _properties->begin(); i != _properties->end(); ++i) {
1588                 PropertyBase* prop = i->second->maybe_clone_self_if_found_in_history_node (history_node);
1589
1590                 if (prop) {
1591                         prop_list->add (prop);
1592                 }
1593         }
1594
1595         return prop_list;
1596 }