do not crash when loading old history files with MIDI edits; add all notes in region...
[ardour.git] / libs / ardour / playlist.cc
index da3a812123b0744cb1b1526b5eac7a4e5ef2965b..cd53f35d95d7772ff26917c235f23b61fde229e2 100644 (file)
 
 #include <sigc++/bind.h>
 
-#include <pbd/failed_constructor.h>
-#include <pbd/stl_delete.h>
-#include <pbd/xml++.h>
-#include <pbd/stacktrace.h>
-
-#include <ardour/playlist.h>
-#include <ardour/session.h>
-#include <ardour/region.h>
-#include <ardour/region_factory.h>
-#include <ardour/playlist_factory.h>
-#include <ardour/transient_detector.h>
+#include "pbd/failed_constructor.h"
+#include "pbd/stl_delete.h"
+#include "pbd/xml++.h"
+#include "pbd/stacktrace.h"
+
+#include "ardour/playlist.h"
+#include "ardour/session.h"
+#include "ardour/region.h"
+#include "ardour/region_factory.h"
+#include "ardour/playlist_factory.h"
+#include "ardour/transient_detector.h"
 
 #include "i18n.h"
 
@@ -60,6 +60,23 @@ struct RegionSortByLayer {
     }
 };
 
+struct RegionSortByLayerWithPending {
+       bool operator () (boost::shared_ptr<Region> a, boost::shared_ptr<Region> b) {
+               
+               double p = a->layer ();
+               if (a->pending_explicit_relayer()) {
+                       p += 0.5;
+               }
+               
+               double q = b->layer ();
+               if (b->pending_explicit_relayer()) {
+                       q += 0.5;
+               }
+               
+               return p < q;
+       }
+};
+
 struct RegionSortByPosition {
     bool operator() (boost::shared_ptr<Region> a, boost::shared_ptr<Region> b) {
            return a->position() < b->position();
@@ -246,27 +263,14 @@ Playlist::init (bool hide)
        _frozen = false;
        layer_op_counter = 0;
        freeze_length = 0;
+       _explicit_relayering = false;
 
        Modified.connect (mem_fun (*this, &Playlist::mark_session_dirty));
 }
 
-Playlist::Playlist (const Playlist& pl)
-       : SessionObject(pl._session, pl._name)
-       , _type(pl.data_type())
-{
-       fatal << _("playlist const copy constructor called") << endmsg;
-}
-
-Playlist::Playlist (Playlist& pl)
-       : SessionObject(pl._session, pl._name)
-       , _type(pl.data_type())
-{
-       fatal << _("playlist non-const copy constructor called") << endmsg;
-}
-
 Playlist::~Playlist ()
 {
-       { 
+       {
                RegionLock rl (this);
 
                for (set<boost::shared_ptr<Region> >::iterator i = all_regions.begin(); i != all_regions.end(); ++i) {
@@ -331,7 +335,6 @@ Playlist::release_notifications ()
        } 
 }
 
-
 void
 Playlist::notify_modified ()
 {
@@ -357,10 +360,29 @@ Playlist::notify_region_removed (boost::shared_ptr<Region> r)
                pending_length = false;
                LengthChanged (); /* EMIT SIGNAL */
                pending_modified = false;
+               RegionRemoved (boost::weak_ptr<Region> (r)); /* EMIT SIGNAL */
                Modified (); /* EMIT SIGNAL */
        }
 }
 
+void
+Playlist::notify_region_moved (boost::shared_ptr<Region> r)
+{
+       Evoral::RangeMove<nframes_t> const move (r->last_position (), r->length (), r->position ());
+                       
+       if (holding_state ()) {
+
+               pending_range_moves.push_back (move);
+               
+       } else {
+
+               list< Evoral::RangeMove<nframes_t> > m;
+               m.push_back (move);
+               RangesMoved (m);
+       }
+
+}
+
 void
 Playlist::notify_region_added (boost::shared_ptr<Region> r)
 {
@@ -376,6 +398,7 @@ Playlist::notify_region_added (boost::shared_ptr<Region> r)
                pending_length = false;
                LengthChanged (); /* EMIT SIGNAL */
                pending_modified = false;
+               RegionAdded (boost::weak_ptr<Region> (r)); /* EMIT SIGNAL */
                Modified (); /* EMIT SIGNAL */
        }
 }
@@ -416,21 +439,25 @@ Playlist::flush_notifications ()
        // pending_bounds.sort (cmp);
 
        for (RegionList::iterator r = pending_bounds.begin(); r != pending_bounds.end(); ++r) {
-               if (Config->get_layer_model() == MoveAddHigher) {
+               if (_session.config.get_layer_model() == MoveAddHigher) {
                        timestamp_layer_op (*r);
                }
+
                pending_length = true;
                dependent_checks_needed.insert (*r);
-               n++;
-       }
 
-       for (s = pending_adds.begin(); s != pending_adds.end(); ++s) {
-               dependent_checks_needed.insert (*s);
                n++;
        }
 
        for (s = pending_removes.begin(); s != pending_removes.end(); ++s) {
                remove_dependents (*s);
+               RegionRemoved (boost::weak_ptr<Region> (*s)); /* EMIT SIGNAL */
+               n++;
+       }
+
+       for (s = pending_adds.begin(); s != pending_adds.end(); ++s) {
+               RegionAdded (boost::weak_ptr<Region> (*s)); /* EMIT SIGNAL */
+               dependent_checks_needed.insert (*s);
                n++;
        }
 
@@ -446,16 +473,20 @@ Playlist::flush_notifications ()
                }
                pending_modified = false;
                Modified (); /* EMIT SIGNAL */
-               
        }
 
        for (s = dependent_checks_needed.begin(); s != dependent_checks_needed.end(); ++s) {
                check_dependents (*s, false);
        }
 
+       if (!pending_range_moves.empty ()) {
+               RangesMoved (pending_range_moves);
+       }
+
        pending_adds.clear ();
        pending_removes.clear ();
        pending_bounds.clear ();
+       pending_range_moves.clear ();
 
        in_flush = false;
 }
@@ -465,15 +496,18 @@ Playlist::flush_notifications ()
  *************************************************************/
 
 void
-Playlist::add_region (boost::shared_ptr<Region> region, nframes_t position, float times) 
-{ 
+Playlist::add_region (boost::shared_ptr<Region> region, nframes_t position, float times, bool auto_partition
+{
        RegionLock rlock (this);
-       delay_notifications();
        times = fabs (times);
        
        int itimes = (int) floor (times);
 
        nframes_t pos = position;
+
+       if(times == 1 && auto_partition){
+               partition(pos, (nframes_t) (pos + region->length()), true);
+       }
        
        if (itimes >= 1) {
                add_region_internal (region, pos);
@@ -502,9 +536,7 @@ Playlist::add_region (boost::shared_ptr<Region> region, nframes_t position, floa
                add_region_internal (sub, pos);
        }
 
-
        possibly_splice_unlocked (position, (pos + length) - position, boost::shared_ptr<Region>());
-       release_notifications ();
 }
 
 void
@@ -519,10 +551,15 @@ Playlist::set_region_ownership ()
        }
 }
 
-void
+bool
 Playlist::add_region_internal (boost::shared_ptr<Region> region, nframes_t position)
 {
+       if (region->data_type() != _type){
+               return false;
+       }
+
        RegionSortByPosition cmp;
+       
        nframes_t old_length = 0;
 
        if (!holding_state()) {
@@ -553,14 +590,20 @@ Playlist::add_region_internal (boost::shared_ptr<Region> region, nframes_t posit
        notify_region_added (region);
        
        if (!holding_state ()) {
+
                check_dependents (region, false);
+
                if (old_length != _get_maximum_extent()) {
                        notify_length_changed ();
                }
        }
 
-       region->StateChanged.connect (sigc::bind (mem_fun (this, &Playlist::region_changed_proxy), 
-                                                 boost::weak_ptr<Region> (region)));
+       region_state_changed_connections.push_back (
+               region->StateChanged.connect (sigc::bind (mem_fun (this, &Playlist::region_changed_proxy), 
+                                                         boost::weak_ptr<Region> (region)))
+               );
+
+       return true;
 }
 
 void
@@ -660,11 +703,11 @@ Playlist::get_region_list_equivalent_regions (boost::shared_ptr<Region> other, v
 }
 
 void
-Playlist::partition (nframes_t start, nframes_t end, bool just_top_level)
+Playlist::partition (nframes_t start, nframes_t end, bool cut)
 {
        RegionList thawlist;
 
-       partition_internal (start, end, false, thawlist);
+       partition_internal (start, end, cut, thawlist);
 
        for (RegionList::iterator i = thawlist.begin(); i != thawlist.end(); ++i) {
                (*i)->thaw ("separation");
@@ -674,53 +717,66 @@ Playlist::partition (nframes_t start, nframes_t end, bool just_top_level)
 void
 Playlist::partition_internal (nframes_t start, nframes_t end, bool cutting, RegionList& thawlist)
 {
-       RegionLock rlock (this);
-       boost::shared_ptr<Region> region;
-       boost::shared_ptr<Region> current;
-       string new_name;
-       RegionList::iterator tmp;
-       OverlapType overlap;
-       nframes_t pos1, pos2, pos3, pos4;
        RegionList new_regions;
 
-       in_partition = true;
-
-       /* need to work from a copy, because otherwise the regions we add during the process
-          get operated on as well.
-       */
-
-       RegionList copy = regions;
+       {
+               RegionLock rlock (this);
 
-       for (RegionList::iterator i = copy.begin(); i != copy.end(); i = tmp) {
+               boost::shared_ptr<Region> region;
+               boost::shared_ptr<Region> current;
+               string new_name;
+               RegionList::iterator tmp;
+               OverlapType overlap;
+               nframes_t pos1, pos2, pos3, pos4;
                
-               tmp = i;
-               ++tmp;
-
-               current = *i;
+               in_partition = true;
                
-               if (current->first_frame() == start && current->last_frame() == end) {
-                       if (cutting) {
-                               remove_region_internal (current);
-                       }
-                       continue;
-               }
+               /* need to work from a copy, because otherwise the regions we add during the process
+                  get operated on as well.
+               */
                
-               if ((overlap = current->coverage (start, end)) == OverlapNone) {
-                       continue;
-               }
+               RegionList copy = regions;
                
-               pos1 = current->position();
-               pos2 = start;
-               pos3 = end;
-               pos4 = current->last_frame();
+               for (RegionList::iterator i = copy.begin(); i != copy.end(); i = tmp) {
 
-               if (overlap == OverlapInternal) {
+                       tmp = i;
+                       ++tmp;
                        
-                       /* split: we need 3 new regions, the front, middle and end.
-                          cut:   we need 2 regions, the front and end.
+                       current = *i;
+
+                       if (current->first_frame() >= start && current->last_frame() < end) {
+
+                               if (cutting) {
+                                       remove_region_internal (current);
+                               }
+
+                               continue;
+                       }
+                       
+                       /* coverage will return OverlapStart if the start coincides
+                          with the end point. we do not partition such a region,
+                          so catch this special case.
                        */
+
+                       if (current->first_frame() >= end) {
+                               continue;
+                       }
+
+                       if ((overlap = current->coverage (start, end)) == OverlapNone) {
+                               continue;
+                       }
+
+                       pos1 = current->position();
+                       pos2 = start;
+                       pos3 = end;
+                       pos4 = current->last_frame();
                        
-                       /*
+                       if (overlap == OverlapInternal) {
+                               /* split: we need 3 new regions, the front, middle and end.
+                                  cut:   we need 2 regions, the front and end.
+                               */
+                               
+                               /*
                                         start                 end
                          ---------------*************************------------
                                         P1  P2              P3  P4
@@ -729,37 +785,36 @@ Playlist::partition_internal (nframes_t start, nframes_t end, bool cutting, Regi
                          CUT
                          ---------------*****----------------====------------
                          
-                       */
+                               */
 
-                       if (!cutting) {
-                               
-                               /* "middle" ++++++ */
+                               if (!cutting) {
+                                       /* "middle" ++++++ */
+                                       
+                                       _session.region_name (new_name, current->name(), false);
+                                       region = RegionFactory::create (current, pos2 - pos1, pos3 - pos2, new_name,
+                                                                       regions.size(), Region::Flag(current->flags()|Region::Automatic|Region::LeftOfSplit|Region::RightOfSplit));
+                                       add_region_internal (region, start);
+                                       new_regions.push_back (region);
+                               }
                                
-                               _session.region_name (new_name, current->name(), false);
-                               region = RegionFactory::create (current, pos2 - pos1, pos3 - pos2, new_name,
-                                                      regions.size(), Region::Flag(current->flags()|Region::Automatic|Region::LeftOfSplit|Region::RightOfSplit));
-                               add_region_internal (region, start);
-                               new_regions.push_back (region);
-                       }
+                               /* "end" ====== */
                        
-                       /* "end" ====== */
-                       
-                       _session.region_name (new_name, current->name(), false);
-                       region = RegionFactory::create (current, pos3 - pos1, pos4 - pos3, new_name, 
-                                              regions.size(), Region::Flag(current->flags()|Region::Automatic|Region::RightOfSplit));
-
-                       add_region_internal (region, end);
-                       new_regions.push_back (region);
+                               _session.region_name (new_name, current->name(), false);
+                               region = RegionFactory::create (current, pos3 - pos1, pos4 - pos3, new_name, 
+                                                               regions.size(), Region::Flag(current->flags()|Region::Automatic|Region::RightOfSplit));
 
-                       /* "front" ***** */
+                               add_region_internal (region, end);
+                               new_regions.push_back (region);
                                
-                       current->freeze ();
-                       thawlist.push_back (current);
-                       current->trim_end (pos2, this);
+                               /* "front" ***** */
+                               
+                               current->freeze ();
+                               thawlist.push_back (current);
+                               current->trim_end (pos2, this);
 
-               } else if (overlap == OverlapEnd) {
+                       } else if (overlap == OverlapEnd) {
 
-                       /*
+                               /*
                                                              start           end
                                    ---------------*************************------------
                                                   P1           P2         P4   P3
@@ -767,33 +822,33 @@ Playlist::partition_internal (nframes_t start, nframes_t end, bool cutting, Regi
                                    ---------------**************+++++++++++------------
                                     CUT:                                                  
                                    ---------------**************-----------------------
+                               */
+                               
+                               if (!cutting) {
 
-                       */
+                                       /* end +++++ */
+                                       
+                                       _session.region_name (new_name, current->name(), false);
+                                       region = RegionFactory::create (current, pos2 - pos1, pos4 - pos2, new_name, (layer_t) regions.size(),
+                                                                       Region::Flag(current->flags()|Region::Automatic|Region::LeftOfSplit));
 
-                       if (!cutting) {
+                                       add_region_internal (region, start);
+                                       new_regions.push_back (region);
+                               }
                                
-                               /* end +++++ */
+                               /* front ****** */
                                
-                               _session.region_name (new_name, current->name(), false);
-                               region = RegionFactory::create (current, pos2 - pos1, pos4 - pos2, new_name, (layer_t) regions.size(),
-                                                      Region::Flag(current->flags()|Region::Automatic|Region::LeftOfSplit));
-                               add_region_internal (region, start);
-                               new_regions.push_back (region);
-                       }
+                               current->freeze ();
+                               thawlist.push_back (current);
+                               current->trim_end (pos2, this);
 
-                       /* front ****** */
+                       } else if (overlap == OverlapStart) {
 
-                       current->freeze ();
-                       thawlist.push_back (current);
-                       current->trim_end (pos2, this);
-
-               } else if (overlap == OverlapStart) {
-
-                       /* split: we need 2 regions: the front and the end.
-                          cut: just trim current to skip the cut area
-                       */
+                               /* split: we need 2 regions: the front and the end.
+                                  cut: just trim current to skip the cut area
+                               */
                                
-                       /*
+                               /*
                                                        start           end
                                    ---------------*************************------------
                                       P2          P1 P3                   P4          
@@ -803,31 +858,30 @@ Playlist::partition_internal (nframes_t start, nframes_t end, bool cutting, Regi
                                    CUT:
                                    -------------------*********************------------
                                    
-                       */
+                               */
 
-                       if (!cutting) {
-                               
-                               /* front **** */
-                                _session.region_name (new_name, current->name(), false);
-                                region = RegionFactory::create (current, 0, pos3 - pos1, new_name,
-                                                       regions.size(), Region::Flag(current->flags()|Region::Automatic|Region::RightOfSplit));
-                                add_region_internal (region, pos1);
-                                new_regions.push_back (region);
-                       } 
-                       
-                       /* end */
-                       
-                       current->freeze ();
-                       thawlist.push_back (current);
-                       current->trim_front (pos3, this);
+                               if (!cutting) {
+                                       /* front **** */
+                                       _session.region_name (new_name, current->name(), false);
+                                       region = RegionFactory::create (current, 0, pos3 - pos1, new_name,
+                                                                       regions.size(), Region::Flag(current->flags()|Region::Automatic|Region::RightOfSplit));
 
-               } else if (overlap == OverlapExternal) {
+                                       add_region_internal (region, pos1);
+                                       new_regions.push_back (region);
+                               } 
+                               
+                               /* end */
+                               
+                               current->freeze ();
+                               thawlist.push_back (current);
+                               current->trim_front (pos3, this);
+                       } else if (overlap == OverlapExternal) {
 
-                       /* split: no split required.
-                          cut: remove the region.
-                       */
+                               /* split: no split required.
+                                  cut: remove the region.
+                               */
                                
-                       /*
+                               /*
                                       start                                      end
                                    ---------------*************************------------
                                       P2          P1 P3                   P4          
@@ -837,16 +891,18 @@ Playlist::partition_internal (nframes_t start, nframes_t end, bool cutting, Regi
                                    CUT:
                                    ----------------------------------------------------
                                    
-                       */
+                               */
+                               
+                               if (cutting) {
+                                       remove_region_internal (current);
+                               }
 
-                       if (cutting) {
-                               remove_region_internal (current);
+                               new_regions.push_back (current);
                        }
-                       new_regions.push_back (current);
                }
-       }
 
-       in_partition = false;
+               in_partition = false;
+       }
 
        for (RegionList::iterator i = new_regions.begin(); i != new_regions.end(); ++i) {
                check_dependents (*i, false);
@@ -1008,11 +1064,68 @@ Playlist::duplicate (boost::shared_ptr<Region> region, nframes_t position, float
        }
 }
 
+void
+Playlist::shift (nframes64_t at, nframes64_t distance, bool move_intersected, bool ignore_music_glue)
+{
+       RegionLock rlock (this);
+       RegionList copy (regions);
+       RegionList fixup;
+
+       for (RegionList::iterator r = copy.begin(); r != copy.end(); ++r) {
+
+               if ((*r)->last_frame() < at) {
+                       /* too early */
+                       continue;
+               }
+               
+               if (at > (*r)->first_frame() && at < (*r)->last_frame()) {
+                       /* intersected region */
+                       if (!move_intersected) {
+                               continue;
+                       }
+               }
+               
+               /* do not move regions glued to music time - that
+                  has to be done separately.
+               */
+
+               if (!ignore_music_glue && (*r)->positional_lock_style() != Region::AudioTime) {
+                       fixup.push_back (*r);
+                       continue;
+               }
+
+               (*r)->set_position ((*r)->position() + distance, this);
+       }
+
+       for (RegionList::iterator r = fixup.begin(); r != fixup.end(); ++r) {
+               (*r)->recompute_position_from_lock_style ();
+       }
+}
+
+void
+Playlist::split (nframes64_t at)
+{
+       RegionLock rlock (this);
+       RegionList copy (regions);
+
+       /* use a copy since this operation can modify the region list
+        */
+
+       for (RegionList::iterator r = copy.begin(); r != copy.end(); ++r) {
+               _split_region (*r, at);
+       }
+}
+
 void
 Playlist::split_region (boost::shared_ptr<Region> region, nframes_t playlist_position)
 {
        RegionLock rl (this);
+       _split_region (region, playlist_position);
+}
 
+void
+Playlist::_split_region (boost::shared_ptr<Region> region, nframes_t playlist_position)
+{
        if (!region->covers (playlist_position)) {
                return;
        }
@@ -1181,7 +1294,7 @@ Playlist::region_bounds_changed (Change what_changed, boost::shared_ptr<Region>
                if (holding_state ()) {
                        pending_bounds.push_back (region);
                } else {
-                       if (Config->get_layer_model() == MoveAddHigher) {
+                       if (_session.config.get_layer_model() == MoveAddHigher) {
                                /* it moved or changed length, so change the timestamp */
                                timestamp_layer_op (region);
                        }
@@ -1218,20 +1331,22 @@ Playlist::region_changed (Change what_changed, boost::shared_ptr<Region> region)
                return false;
        }
 
-       {
-               if (what_changed & BoundsChanged) {
-                       region_bounds_changed (what_changed, region);
-                       save = !(_splicing || _nudging);
-               }
+       if (what_changed & BoundsChanged) {
+               region_bounds_changed (what_changed, region);
+               save = !(_splicing || _nudging);
+       }
                
-               if ((what_changed & our_interests) && 
-                   !(what_changed & Change (ARDOUR::PositionChanged|ARDOUR::LengthChanged))) {
-                       check_dependents (region, false);
-               }
+       if ((what_changed & our_interests) && 
+           !(what_changed & Change (ARDOUR::PositionChanged|ARDOUR::LengthChanged))) {
+               check_dependents (region, false);
+       }
+
+       if (what_changed & Change (ARDOUR::PositionChanged)) {
+               notify_region_moved (region);
+       }
                
-               if (what_changed & our_interests) {
-                       save = true;
-               }
+       if (what_changed & our_interests) {
+               save = true;
        }
 
        return save;
@@ -1248,11 +1363,21 @@ Playlist::drop_regions ()
 void
 Playlist::clear (bool with_signals)
 {
-       { 
+       {
                RegionLock rl (this);
+
+               for (
+                       std::list<sigc::connection>::iterator i = region_state_changed_connections.begin ();
+                       i != region_state_changed_connections.end ();
+                       ++i
+               ) {
+                       i->disconnect ();       
+               }
+                    
                for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
                        pending_removes.insert (*i);
                }
+
                regions.clear ();
        }
 
@@ -1293,7 +1418,38 @@ Playlist::top_region_at (nframes_t frame)
 
        delete rlist;
        return region;
-}      
+}
+
+boost::shared_ptr<Region>
+Playlist::top_unmuted_region_at (nframes_t frame)
+
+{
+       RegionLock rlock (this);
+       RegionList *rlist = find_regions_at (frame);
+
+       for (RegionList::iterator i = rlist->begin(); i != rlist->end(); ) {
+
+               RegionList::iterator tmp = i;
+               ++tmp;
+
+               if ((*i)->muted()) {
+                       rlist->erase (i);
+               }
+
+               i = tmp;
+       }
+       
+       boost::shared_ptr<Region> region;
+       
+       if (rlist->size()) {
+               RegionSortByLayer cmp;
+               rlist->sort (cmp);
+               region = rlist->back();
+       } 
+
+       delete rlist;
+       return region;
+}
 
 Playlist::RegionList*
 Playlist::regions_to_read (nframes_t start, nframes_t end)
@@ -1496,9 +1652,12 @@ Playlist::find_next_region (nframes_t frame, RegionPoint point, int dir)
        boost::shared_ptr<Region> ret;
        nframes_t closest = max_frames;
 
+       bool end_iter = false;
 
        for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
 
+               if(end_iter) break;
+
                nframes_t distance;
                boost::shared_ptr<Region> r = (*i);
                nframes_t pos = 0;
@@ -1511,30 +1670,36 @@ Playlist::find_next_region (nframes_t frame, RegionPoint point, int dir)
                        pos = r->last_frame ();
                        break;
                case SyncPoint:
-                       pos = r->adjust_to_sync (r->first_frame());
+                       pos = r->sync_position ();
+                       // r->adjust_to_sync (r->first_frame());
                        break;
                }
 
                switch (dir) {
                case 1: /* forwards */
 
-                       if (pos >= frame) {
+                       if (pos > frame) {
                                if ((distance = pos - frame) < closest) {
                                        closest = distance;
                                        ret = r;
+                                       end_iter = true;
                                }
                        }
 
                        break;
 
                default: /* backwards */
-
-                       if (pos <= frame) {
+                       
+                       if (pos < frame) {
                                if ((distance = frame - pos) < closest) {
                                        closest = distance;
                                        ret = r;
                                }
                        }
+                       else {
+                               end_iter = true;
+                       }
+
                        break;
                }
        }
@@ -1553,14 +1718,10 @@ Playlist::find_next_region_boundary (nframes64_t frame, int dir)
        if (dir > 0) {
 
                for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
-                       
+
                        boost::shared_ptr<Region> r = (*i);
                        nframes64_t distance;
-                       nframes64_t end = r->position() + r->length();
-                       bool reset;
-
-                       reset = false;
-
+                       
                        if (r->first_frame() > frame) {
 
                                distance = r->first_frame() - frame;
@@ -1568,24 +1729,18 @@ Playlist::find_next_region_boundary (nframes64_t frame, int dir)
                                if (distance < closest) {
                                        ret = r->first_frame();
                                        closest = distance;
-                                       reset = true;
                                }
                        }
 
-                       if (end > frame) {
+                       if (r->last_frame () > frame) {
                                
-                               distance = end - frame;
+                               distance = r->last_frame () - frame;
                                
                                if (distance < closest) {
-                                       ret = end;
+                                       ret = r->last_frame ();
                                        closest = distance;
-                                       reset = true;
                                }
                        }
-
-                       if (reset) {
-                               break;
-                       }
                }
 
        } else {
@@ -1594,9 +1749,6 @@ Playlist::find_next_region_boundary (nframes64_t frame, int dir)
                        
                        boost::shared_ptr<Region> r = (*i);
                        nframes64_t distance;
-                       bool reset;
-
-                       reset = false;
 
                        if (r->last_frame() < frame) {
 
@@ -1605,23 +1757,18 @@ Playlist::find_next_region_boundary (nframes64_t frame, int dir)
                                if (distance < closest) {
                                        ret = r->last_frame();
                                        closest = distance;
-                                       reset = true;
                                }
                        }
 
                        if (r->first_frame() < frame) {
-                               distance = frame - r->last_frame();
                                
+                               distance = frame - r->first_frame();
+
                                if (distance < closest) {
                                        ret = r->first_frame();
                                        closest = distance;
-                                       reset = true;
                                }
                        }
-
-                       if (reset) {
-                               break;
-                       }
                }
        }
 
@@ -1632,6 +1779,7 @@ Playlist::find_next_region_boundary (nframes64_t frame, int dir)
 
 
 
+
 void
 Playlist::mark_session_dirty ()
 {
@@ -1735,15 +1883,17 @@ Playlist::set_state (const XMLNode& node)
 XMLNode&
 Playlist::get_state()
 {
-       return state(true);
+       return state (true);
 }
 
 XMLNode&
 Playlist::get_template()
 {
-       return state(false);
+       return state (false);
 }
 
+/** @param full_state true to include regions in the returned state, otherwise false.
+ */
 XMLNode&
 Playlist::state (bool full_state)
 {
@@ -1814,55 +1964,17 @@ Playlist::bump_name (string name, Session &session)
        string newname = name;
 
        do {
-               newname = Playlist::bump_name_once (newname);
+               newname = bump_name_once (newname);
        } while (session.playlist_by_name (newname)!=NULL);
 
        return newname;
 }
 
-string
-Playlist::bump_name_once (string name)
-{
-       string::size_type period;
-       string newname;
-
-       if ((period = name.find_last_of ('.')) == string::npos) {
-               newname  = name;
-               newname += ".1";
-       } else {
-               int isnumber = 1;
-               const char *last_element = name.c_str() + period + 1;
-               for (size_t i = 0; i < strlen(last_element); i++) {
-                       if (!isdigit(last_element[i])) {
-                               isnumber = 0;
-                               break;
-                       }
-               }
-
-               errno = 0;
-               long int version = strtol (name.c_str()+period+1, (char **)NULL, 10);
-
-               if (isnumber == 0 || errno != 0) {
-                       // last_element is not a number, or is too large
-                       newname  = name;
-                       newname += ".1";
-               } else {
-                       char buf[32];
-
-                       snprintf (buf, sizeof(buf), "%ld", version+1);
-               
-                       newname  = name.substr (0, period+1);
-                       newname += buf;
-               }
-       }
-
-       return newname;
-}
 
 layer_t
 Playlist::top_layer() const
 {
-       RegionLock rlock (const_cast<Playlist *> (this));
+       RegionLock rlock (const_cast<Playlist *> (this));       
        layer_t top = 0;
 
        for (RegionList::const_iterator i = regions.begin(); i != regions.end(); ++i) {
@@ -1887,12 +1999,30 @@ Playlist::relayer ()
        /* don't send multiple Modified notifications
           when multiple regions are relayered.
        */
+
        freeze ();
 
-       /* build up a new list of regions on each layer */
+       /* Build up a new list of regions on each layer, stored in a set of lists
+          each of which represent some period of time on some layer.  The idea
+          is to avoid having to search the entire region list to establish whether
+          each region overlaps another */
+
+       /* how many pieces to divide this playlist's time up into */
+       int const divisions = 512;
 
-       std::vector<RegionList> layers;
+       /* find the start and end positions of the regions on this playlist */
+       nframes_t start = UINT_MAX;
+       nframes_t end = 0;
+       for (RegionList::const_iterator i = regions.begin(); i != regions.end(); ++i) {
+               start = min (start, (*i)->position());
+               end = max (end, (*i)->position() + (*i)->length());
+       }
+
+       /* hence the size of each time division */
+       double const division_size = (end - start) / double (divisions);
+
+       vector<vector<RegionList> > layers;
+       layers.push_back (vector<RegionList> (divisions));
 
        /* we want to go through regions from desired lowest to desired highest layer,
           which depends on the layer model
@@ -1900,50 +2030,74 @@ Playlist::relayer ()
 
        RegionList copy = regions;
 
-       /* sort according to the model */
+       /* sort according to the model and the layering mode that we're in */
+
+       if (_explicit_relayering) {
+
+               copy.sort (RegionSortByLayerWithPending ());
 
-       if (Config->get_layer_model() == MoveAddHigher || Config->get_layer_model() == AddHigher) {
-               RegionSortByLastLayerOp cmp;
-               copy.sort (cmp);
+       } else if (_session.config.get_layer_model() == MoveAddHigher || _session.config.get_layer_model() == AddHigher) {
+
+               copy.sort (RegionSortByLastLayerOp ());
+               
        }
-       
+
        for (RegionList::iterator i = copy.begin(); i != copy.end(); ++i) {
 
+               /* reset the pending explicit relayer flag for every region, now that we're relayering */
+               (*i)->set_pending_explicit_relayer (false);
+
+               /* find the time divisions that this region covers */
+               int const start_division = floor ( ((*i)->position() - start) / division_size);
+               int end_division = floor ( ((*i)->position() + (*i)->length() - start) / division_size );
+               if (end_division == divisions) {
+                       end_division--;
+               }
+
+               assert (end_division < divisions);
+
                /* find the lowest layer that this region can go on */
                size_t j = layers.size();
                while (j > 0) {
                        /* try layer j - 1; it can go on if it overlaps no other region
                           that is already on that layer
                        */
-                       RegionList::iterator k = layers[j - 1].begin();
-                       while (k != layers[j - 1].end()) {
-                               if ((*k)->overlap_equivalent (*i)) {
+
+                       bool overlap = false;
+                       for (int k = start_division; k <= end_division; ++k) {
+                               RegionList::iterator l = layers[j-1][k].begin ();
+                               while (l != layers[j-1][k].end()) {
+                                       if ((*l)->overlap_equivalent (*i)) {
+                                               overlap = true;
+                                               break;
+                                       }
+                                       l++;
+                               }
+
+                               if (overlap) {
                                        break;
                                }
-                               k++;
                        }
 
-                       if (k != layers[j - 1].end()) {
-                               /* no overlap, so we can use this layer */
+                       if (overlap) {
+                               /* overlap, so we must use layer j */
                                break;
                        }
-                                       
-                       j--;
+                       
+                       --j;
                }
 
                if (j == layers.size()) {
                        /* we need a new layer for this region */
-                       layers.push_back (RegionList ());
+                       layers.push_back (vector<RegionList> (divisions));
                }
 
-               layers[j].push_back (*i);
-       }
-
-       /* first pass: set up the layer numbers in the regions */
-       for (size_t j = 0; j < layers.size(); ++j) {
-               for (RegionList::iterator i = layers[j].begin(); i != layers[j].end(); ++i) {
-                       (*i)->set_layer (j);
+               /* put a reference to this region in each of the divisions that it exists in */
+               for (int k = start_division; k <= end_division; ++k) {
+                       layers[j][k].push_back (*i);
                }
+
+               (*i)->set_layer (j);
        }
 
        /* sending Modified means that various kinds of layering
@@ -1992,8 +2146,8 @@ void
 Playlist::raise_region_to_top (boost::shared_ptr<Region> region)
 {
        /* does nothing useful if layering mode is later=higher */
-       if ((Config->get_layer_model() == MoveAddHigher) ||
-           (Config->get_layer_model() == AddHigher)) {
+       if ((_session.config.get_layer_model() == MoveAddHigher) ||
+           (_session.config.get_layer_model() == AddHigher)) {
                timestamp_layer_op (region);
                relayer ();
        }
@@ -2003,8 +2157,8 @@ void
 Playlist::lower_region_to_bottom (boost::shared_ptr<Region> region)
 {
        /* does nothing useful if layering mode is later=higher */
-       if ((Config->get_layer_model() == MoveAddHigher) ||
-           (Config->get_layer_model() == AddHigher)) {
+       if ((_session.config.get_layer_model() == MoveAddHigher) ||
+           (_session.config.get_layer_model() == AddHigher)) {
                region->set_last_layer_op (0);
                relayer ();
        }
@@ -2334,3 +2488,34 @@ Playlist::update_after_tempo_map_change ()
 
        thaw ();
 }
+
+void
+Playlist::foreach_region (sigc::slot<void, boost::shared_ptr<Region> > s)
+{
+       RegionLock rl (this, false);
+       for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
+               s (*i);
+       }
+}
+
+void
+Playlist::set_explicit_relayering (bool e)
+{
+       if (e == false && _explicit_relayering == true) {
+
+               /* We are changing from explicit to implicit relayering; layering may have been changed whilst
+                  we were in explicit mode, and we don't want that to be undone next time an implicit relayer
+                  occurs.  Hence now we'll set up region last_layer_op values so that an implicit relayer
+                  at this point would keep regions on the same layers.
+
+                  From then on in, it's just you and your towel.
+               */
+
+               RegionLock rl (this);
+               for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
+                       (*i)->set_last_layer_op ((*i)->layer ());
+               }
+       }
+
+       _explicit_relayering = e;
+}