X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fardour%2Ftempo.cc;h=5698b0afe74c57570ecdd1f55544c60b018746f1;hb=4e1f451520975868659f4c00d00883f5f1cd5805;hp=c0e52279e1bd7280633b38eddd6371ddb23471c7;hpb=fe13d08874f08b723df53116e5655c3d229a657e;p=ardour.git

diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index c0e52279e1..5698b0afe7 100644
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -15,7 +15,6 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id$
 */
 
 #include <algorithm>
@@ -44,12 +43,17 @@ Tempo    TempoMap::_default_tempo (120.0);
 
 const double Meter::ticks_per_beat = 1920.0;
 
+double Tempo::frames_per_beat (nframes_t sr, const Meter& meter) const
+{
+	return  ((60.0 * sr) / (_beats_per_minute * meter.note_divisor()/_note_type));
+}
+
 /***********************************************************************/
 
 double
-Meter::frames_per_bar (const Tempo& tempo, jack_nframes_t sr) const
+Meter::frames_per_bar (const Tempo& tempo, nframes_t sr) const
 {
-	return ((60.0 * sr * _beats_per_bar) / tempo.beats_per_minute());
+	return ((60.0 * sr * _beats_per_bar) / (tempo.beats_per_minute() * _note_type/tempo.note_type()));
 }
 
 /***********************************************************************/
@@ -87,6 +91,16 @@ TempoSection::TempoSection (const XMLNode& node)
 		error << _("TempoSection XML node has an illegal \"beats_per_minute\" value") << endmsg;
 		throw failed_constructor();
 	}
+	
+	if ((prop = node.property ("note-type")) == 0) {
+		/* older session, make note type be quarter by default */
+		_note_type = 4.0;
+	} else {
+		if (sscanf (prop->value().c_str(), "%lf", &_note_type) != 1 || _note_type < 1.0) {
+			error << _("TempoSection XML node has an illegal \"note-type\" value") << endmsg;
+			throw failed_constructor();
+		}
+	}
 
 	if ((prop = node.property ("movable")) == 0) {
 		error << _("TempoSection XML node has no \"movable\" property") << endmsg;
@@ -110,6 +124,8 @@ TempoSection::get_state() const
 	root->add_property ("start", buf);
 	snprintf (buf, sizeof (buf), "%f", _beats_per_minute);
 	root->add_property ("beats-per-minute", buf);
+	snprintf (buf, sizeof (buf), "%f", _note_type);
+	root->add_property ("note-type", buf);
 	snprintf (buf, sizeof (buf), "%s", movable()?"yes":"no");
 	root->add_property ("movable", buf);
 
@@ -200,19 +216,18 @@ struct MetricSectionSorter {
     }
 };
 
-TempoMap::TempoMap (jack_nframes_t fr)
+TempoMap::TempoMap (nframes_t fr)
 {
 	metrics = new Metrics;
 	_frame_rate = fr;
 	last_bbt_valid = false;
 	BBT_Time start;
-	in_set_state = false;
 	
 	start.bars = 1;
 	start.beats = 1;
 	start.ticks = 0;
 
-	TempoSection *t = new TempoSection (start, _default_tempo.beats_per_minute());
+	TempoSection *t = new TempoSection (start, _default_tempo.beats_per_minute(), _default_tempo.note_type());
 	MeterSection *m = new MeterSection (start, _default_meter.beats_per_bar(), _default_meter.note_divisor());
 
 	t->set_movable (false);
@@ -222,8 +237,6 @@ TempoMap::TempoMap (jack_nframes_t fr)
 	
 	metrics->push_back (t);
 	metrics->push_back (m);
-	
-	save_state (_("initial"));
 }
 
 TempoMap::~TempoMap ()
@@ -233,30 +246,49 @@ TempoMap::~TempoMap ()
 int
 TempoMap::move_metric_section (MetricSection& section, const BBT_Time& when)
 {
-	if (when == section.start()) {
+	if (when == section.start() || !section.movable()) {
 		return -1;
 	}
 
-	if (!section.movable()) {
-		return 1;
-	}
-
-	Glib::Mutex::Lock lm (lock);
+	Glib::RWLock::WriterLock  lm (lock);
 	MetricSectionSorter cmp;
-	BBT_Time corrected (when);
-	
-	if (dynamic_cast<MeterSection*>(&section) != 0) {
-		if (corrected.beats > 1) {
-			corrected.beats = 1;
-			corrected.bars++;
+
+	if (when.beats != 1) {
+
+		/* position by audio frame, then recompute BBT timestamps from the audio ones */
+
+		nframes_t frame = frame_time (when);
+		// cerr << "nominal frame time = " << frame << endl;
+
+		nframes_t prev_frame = round_to_type (frame, -1, Beat);
+		nframes_t next_frame = round_to_type (frame, 1, Beat);
+		
+		// cerr << "previous beat at " << prev_frame << " next at " << next_frame << endl;
+
+		/* use the closest beat */
+
+		if ((frame - prev_frame) < (next_frame - frame)) {
+			frame = prev_frame;
+		} else {
+			frame = next_frame;
 		}
+		
+		// cerr << "actual frame time = " << frame << endl;
+		section.set_frame (frame);
+		// cerr << "frame time = " << section.frame() << endl;
+		timestamp_metrics (false);
+		// cerr << "new BBT time = " << section.start() << endl;
+		metrics->sort (cmp);
+
+	} else {
+
+		/* positioned at bar start already, so just put it there */
+
+		section.set_start (when);
+		metrics->sort (cmp);
+		timestamp_metrics (true);
 	}
-	corrected.ticks = 0;
 
-	section.set_start (corrected);
-	metrics->sort (cmp);
-	timestamp_metrics ();
-	save_state (_("move metric"));
 
 	return 0;
 }
@@ -265,7 +297,7 @@ void
 TempoMap::move_tempo (TempoSection& tempo, const BBT_Time& when)
 {
 	if (move_metric_section (tempo, when) == 0) {
-		send_state_changed (Change (0));
+		StateChanged (Change (0));
 	}
 }
 
@@ -273,10 +305,9 @@ void
 TempoMap::move_meter (MeterSection& meter, const BBT_Time& when)
 {
 	if (move_metric_section (meter, when) == 0) {
-		send_state_changed (Change (0));
+		StateChanged (Change (0));
 	}
 }
-		
 
 void
 TempoMap::remove_tempo (const TempoSection& tempo)
@@ -284,7 +315,7 @@ TempoMap::remove_tempo (const TempoSection& tempo)
 	bool removed = false;
 
 	{
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 		Metrics::iterator i;
 
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -301,7 +332,7 @@ TempoMap::remove_tempo (const TempoSection& tempo)
 	}
 
 	if (removed) {
-		send_state_changed (Change (0));
+		StateChanged (Change (0));
 	}
 }
 
@@ -311,7 +342,7 @@ TempoMap::remove_meter (const MeterSection& tempo)
 	bool removed = false;
 
 	{
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 		Metrics::iterator i;
 
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -325,28 +356,30 @@ TempoMap::remove_meter (const MeterSection& tempo)
 				}
 			}
 		}
-
-		if (removed) {
-			save_state (_("metric removed"));
-		}
 	}
 
 	if (removed) {
-		send_state_changed (Change (0));
+		StateChanged (Change (0));
 	}
 }
 
 void
-TempoMap::do_insert (MetricSection* section)
+TempoMap::do_insert (MetricSection* section, bool with_bbt)
 {
 	Metrics::iterator i;
 
 	for (i = metrics->begin(); i != metrics->end(); ++i) {
 		
-		if ((*i)->start() < section->start()) {
-			continue;
+		if (with_bbt) {
+			if ((*i)->start() < section->start()) {
+				continue;
+			}
+		} else {
+			if ((*i)->frame() < section->frame()) {
+				continue;
+			}			
 		}
-		
+
 		metrics->insert (i, section);
 		break;
 	}
@@ -355,25 +388,34 @@ TempoMap::do_insert (MetricSection* section)
 		metrics->insert (metrics->end(), section);
 	}
 	
-	timestamp_metrics ();
+	timestamp_metrics (with_bbt);
 }	
 
 void
 TempoMap::add_tempo (const Tempo& tempo, BBT_Time where)
 {
 	{
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 
 		/* new tempos always start on a beat */
 	
 		where.ticks = 0;
 		
-		do_insert (new TempoSection (where, tempo.beats_per_minute()));
+		do_insert (new TempoSection (where, tempo.beats_per_minute(), tempo.note_type()), true);
+	}
+
+	StateChanged (Change (0));
+}
 
-		save_state (_("add tempo"));
+void
+TempoMap::add_tempo (const Tempo& tempo, nframes_t where)
+{
+	{
+		Glib::RWLock::WriterLock lm (lock);
+		do_insert (new TempoSection (where, tempo.beats_per_minute(), tempo.note_type()), false);
 	}
 
-	send_state_changed (Change (0));
+	StateChanged (Change (0));
 }
 
 void
@@ -382,29 +424,26 @@ TempoMap::replace_tempo (TempoSection& existing, const Tempo& replacement)
 	bool replaced = false;
 
 	{ 
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 		Metrics::iterator i;
 		
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
 			TempoSection *ts;
 
 			if ((ts = dynamic_cast<TempoSection*>(*i)) != 0 && ts == &existing) {
-				
-				*((Tempo *) ts) = replacement;
+
+				 *((Tempo *) ts) = replacement;
 
 				replaced = true;
-				timestamp_metrics ();
+				timestamp_metrics (true);
+
 				break;
 			}
 		}
-
-		if (replaced) {
-			save_state (_("replace tempo"));
-		}
 	}
 	
 	if (replaced) {
-		send_state_changed (Change (0));
+		StateChanged (Change (0));
 	}
 }
 
@@ -412,7 +451,7 @@ void
 TempoMap::add_meter (const Meter& meter, BBT_Time where)
 {
 	{
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 
 		/* a new meter always starts a new bar on the first beat. so
 		   round the start time appropriately. remember that
@@ -430,12 +469,21 @@ TempoMap::add_meter (const Meter& meter, BBT_Time where)
 		
 		where.ticks = 0;
 
-		do_insert (new MeterSection (where, meter.beats_per_bar(), meter.note_divisor()));
+		do_insert (new MeterSection (where, meter.beats_per_bar(), meter.note_divisor()), true);
+	}
+
+	StateChanged (Change (0));
+}
 
-		save_state (_("add meter"));
+void
+TempoMap::add_meter (const Meter& meter, nframes_t where)
+{
+	{
+		Glib::RWLock::WriterLock lm (lock);
+		do_insert (new MeterSection (where, meter.beats_per_bar(), meter.note_divisor()), false);
 	}
 
-	send_state_changed (Change (0));
+	StateChanged (Change (0));
 }
 
 void
@@ -444,7 +492,7 @@ TempoMap::replace_meter (MeterSection& existing, const Meter& replacement)
 	bool replaced = false;
 
 	{ 
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 		Metrics::iterator i;
 		
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -454,21 +502,75 @@ TempoMap::replace_meter (MeterSection& existing, const Meter& replacement)
 				*((Meter*) ms) = replacement;
 
 				replaced = true;
-				timestamp_metrics ();
+				timestamp_metrics (true);
 				break;
 			}
 		}
-
-		if (replaced) {
-			save_state (_("replaced meter"));
-		}
 	}
 	
 	if (replaced) {
-		send_state_changed (Change (0));
+		StateChanged (Change (0));
 	}
 }
 
+void
+TempoMap::change_initial_tempo (double beats_per_minute, double note_type)
+{
+	Tempo newtempo (beats_per_minute, note_type);
+	TempoSection* t;
+
+	for (Metrics::iterator i = metrics->begin(); i != metrics->end(); ++i) {
+		if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
+			*((Tempo*) t) = newtempo;
+			StateChanged (Change (0));
+			break;
+		}
+	}
+}
+
+void
+TempoMap::change_existing_tempo_at (nframes_t where, double beats_per_minute, double note_type)
+{
+	Tempo newtempo (beats_per_minute, note_type);
+
+	TempoSection* prev;
+	TempoSection* first;
+	Metrics::iterator i;
+
+	/* find the TempoSection immediately preceding "where"
+	 */
+
+	for (first = 0, i = metrics->begin(), prev = 0; i != metrics->end(); ++i) {
+
+		if ((*i)->frame() > where) {
+			break;
+		}
+
+		TempoSection* t;
+
+		if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
+			if (!first) {
+				first = t;
+			}
+			prev = t;
+		}
+	}
+
+	if (!prev) {
+		if (!first) {
+			error << string_compose (_("no tempo sections defined in tempo map - cannot change tempo @ %1"), where) << endmsg;
+			return;
+		}
+
+		prev = first;
+	}
+
+	/* reset */
+
+	*((Tempo*)prev) = newtempo;
+	StateChanged (Change (0));
+}
+
 const MeterSection&
 TempoMap::first_meter () const
 {
@@ -502,47 +604,117 @@ TempoMap::first_tempo () const
 }
 
 void
-TempoMap::timestamp_metrics ()
+TempoMap::timestamp_metrics (bool use_bbt)
 {
 	Metrics::iterator i;
 	const Meter* meter;
 	const Tempo* tempo;
 	Meter *m;
 	Tempo *t;
-	jack_nframes_t current;
-	jack_nframes_t section_frames;
-	BBT_Time start;
-	BBT_Time end;
 
 	meter = &first_meter ();
 	tempo = &first_tempo ();
-	current = 0;
 
-	for (i = metrics->begin(); i != metrics->end(); ++i) {
+	if (use_bbt) {
+
+		// cerr << "\n\n\n ######################\nTIMESTAMP via BBT ##############\n" << endl;
+
+		nframes_t current = 0;
+		nframes_t section_frames;
+		BBT_Time start;
+		BBT_Time end;
+
+		for (i = metrics->begin(); i != metrics->end(); ++i) {
+			
+			end = (*i)->start();
+			
+			section_frames = count_frames_between_metrics (*meter, *tempo, start, end);
+			
+			current += section_frames;
+			
+			start = end;
+			
+			(*i)->set_frame (current);
+			
+			if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
+				tempo = t;
+			} else if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
+				meter = m;
+			} else {
+				fatal << _("programming error: unhandled MetricSection type") << endmsg;
+				/*NOTREACHED*/
+			}
+		}
+
+	} else {
+
+		// cerr << "\n\n\n ######################\nTIMESTAMP via AUDIO ##############\n" << endl;
+
+		bool first = true;
+		MetricSection* prev = 0;
+
+		for (i = metrics->begin(); i != metrics->end(); ++i) {
+
+			BBT_Time bbt;
+			Metric metric (*meter, *tempo);
+			
+			if (prev) {
+				metric.set_start (prev->start());
+				metric.set_frame (prev->frame());
+			} else {
+				// metric will be at frames=0 bbt=1|1|0 by default
+				// which is correct for our purpose
+			}
 		
-		end = (*i)->start();
+			bbt_time_with_metric ((*i)->frame(), bbt, metric);
 
-		section_frames = count_frames_between_metrics (*meter, *tempo, start, end);
+			// cerr << "timestamp @ " << (*i)->frame() << " with " << bbt.bars << "|" << bbt.beats << "|" << bbt.ticks << " => ";
+			
 
-		current += section_frames;
+			if (first) {
+				first = false;
+			} else {
+				
+				if (bbt.ticks > Meter::ticks_per_beat/2) {
+					/* round up to next beat */
+					bbt.beats += 1;
+				} 
 
-		start = end;
+				bbt.ticks = 0;
 
-		(*i)->set_frame (current);
+				if (bbt.beats != 1) {
+					/* round up to next bar */
+					bbt.bars += 1;
+					bbt.beats = 1;
+				}
+			}
+			
+			//s cerr << bbt.bars << "|" << bbt.beats << "|" << bbt.ticks << endl;
+			
+			(*i)->set_start (bbt);
 
-		if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
-			tempo = t;
-		} else if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
-			meter = m;
-		} else {
-			fatal << _("programming error: unhandled MetricSection type") << endmsg;
-			/*NOTREACHED*/
+			if ((t = dynamic_cast<TempoSection*>(*i)) != 0) {
+				tempo = t;
+				// cerr << "NEW TEMPO, frame = " << (*i)->frame() << " start = " << (*i)->start() <<endl;
+			} else if ((m = dynamic_cast<MeterSection*>(*i)) != 0) {
+				meter = m;
+				// cerr << "NEW METER, frame = " << (*i)->frame() << " start = " << (*i)->start() <<endl;
+			} else {
+				fatal << _("programming error: unhandled MetricSection type") << endmsg;
+				/*NOTREACHED*/
+			}
+
+			prev = (*i);
 		}
 	}
+
+	// dump (cerr);
+	// cerr << "###############################################\n\n\n" << endl;
+
 }
 
 TempoMap::Metric
-TempoMap::metric_at (jack_nframes_t frame) const
+TempoMap::metric_at (nframes_t frame) const
 {
 	Metric m (first_meter(), first_tempo());
 	const Meter* meter;
@@ -610,75 +782,78 @@ TempoMap::metric_at (BBT_Time bbt) const
 }
 
 void
-TempoMap::bbt_time (jack_nframes_t frame, BBT_Time& bbt) const
+TempoMap::bbt_time (nframes_t frame, BBT_Time& bbt) const
 {
-	Glib::Mutex::Lock lm (lock);
-	bbt_time_unlocked (frame, bbt);
+        {
+	        Glib::RWLock::ReaderLock lm (lock);
+		bbt_time_unlocked (frame, bbt);
+	}
 }
 
 void
-TempoMap::bbt_time_unlocked (jack_nframes_t frame, BBT_Time& bbt) const
+TempoMap::bbt_time_unlocked (nframes_t frame, BBT_Time& bbt) const
 {
 	bbt_time_with_metric (frame, bbt, metric_at (frame));
 }
 
 void
-TempoMap::bbt_time_with_metric (jack_nframes_t frame, BBT_Time& bbt, const Metric& metric) const
+TempoMap::bbt_time_with_metric (nframes_t frame, BBT_Time& bbt, const Metric& metric) const
 {
-	jack_nframes_t frame_diff;
+	nframes_t frame_diff;
 
-	uint32_t xtra_bars = 0;
-	double xtra_beats = 0;
-	double beats = 0;
+	// cerr << "---- BBT time for " << frame << " using metric @ " << metric.frame() << " BBT " << metric.start() << endl;
 
 	const double beats_per_bar = metric.meter().beats_per_bar();
-	const double frames_per_bar = metric.meter().frames_per_bar (metric.tempo(), _frame_rate);
-	const double beat_frames = metric.tempo().frames_per_beat (_frame_rate);
+	const double ticks_per_frame = metric.tempo().frames_per_beat (_frame_rate, metric.meter()) / Meter::ticks_per_beat;
 
 	/* now compute how far beyond that point we actually are. */
 
 	frame_diff = frame - metric.frame();
 
-	xtra_bars = (uint32_t) floor (frame_diff / frames_per_bar);
-	frame_diff -= (uint32_t) floor (xtra_bars * frames_per_bar);
-	xtra_beats = (double) frame_diff / beat_frames;
-
-
-	/* and set the returned value */
-
-	/* and correct beat/bar shifts to match the meter.
-	  remember: beat and bar counting is 1-based, 
-	  not zero-based 
-	  also the meter may contain a fraction
-	*/
-	
-	bbt.bars = metric.start().bars + xtra_bars; 
-
-	beats = (double) metric.start().beats + xtra_beats;
-
-	bbt.bars += (uint32_t) floor(beats/ (beats_per_bar+1) );
-
-	beats = fmod(beats - 1, beats_per_bar )+ 1.0;
-	bbt.ticks = (uint32_t)( round((beats - floor(beats)) *(double) Meter::ticks_per_beat));
-	bbt.beats = (uint32_t) floor(beats);
-
+        bbt.ticks = metric.start().ticks + (uint32_t)round((double)frame_diff / ticks_per_frame);
+        uint32_t xtra_beats = bbt.ticks / (uint32_t)Meter::ticks_per_beat;
+        bbt.ticks %= (uint32_t)Meter::ticks_per_beat;
+
+        bbt.beats = metric.start().beats + xtra_beats - 1; // correction for 1-based counting, see below for matching operation.
+        bbt.bars = metric.start().bars + (uint32_t)floor((double)bbt.beats / beats_per_bar);
+        bbt.beats = (uint32_t)fmod((double)bbt.beats, beats_per_bar);
+
+        /* if we have a fractional number of beats per bar, we see if
+           we're in the last beat (the fractional one).  if so, we
+           round ticks appropriately and bump to the next bar. */
+        double beat_fraction = beats_per_bar - floor(beats_per_bar);
+        /* XXX one problem here is that I'm not sure how to handle
+           fractional beats that don't evenly divide ticks_per_beat.
+           If they aren't handled consistently, I would guess we'll
+           continue to have strange discrepancies occuring.  Perhaps
+           this will also behave badly in the case of meters like
+           0.1/4, but I can't be bothered to test that.
+        */
+        uint32_t ticks_on_last_beat = (uint32_t)floor(Meter::ticks_per_beat * beat_fraction);
+        if(bbt.beats > (uint32_t)floor(beats_per_bar) &&
+           bbt.ticks >= ticks_on_last_beat) {
+          bbt.ticks -= ticks_on_last_beat;
+          bbt.beats = 0;
+          bbt.bars++;
+        }
+
+        bbt.beats++; // correction for 1-based counting, see above for matching operation.
+
+	// cerr << "-----\t RETURN " << bbt << endl;
 }
 
-
-jack_nframes_t 
+nframes_t 
 TempoMap::count_frames_between ( const BBT_Time& start, const BBT_Time& end) const
 {
-
-        /* for this to work with fractional measure types, start and end have to "legal" BBT types, 
-        that means that  the  beats and ticks should be  inside a bar
+        /* for this to work with fractional measure types, start and end have to be "legal" BBT types, 
+	   that means that the beats and ticks should be inside a bar
 	*/
 
+	nframes_t frames = 0;
+	nframes_t start_frame = 0;
+	nframes_t end_frame = 0;
 
-	jack_nframes_t frames = 0;
-	jack_nframes_t start_frame = 0;
-	jack_nframes_t end_frame = 0;
-
-	Metric m = metric_at(start);
+	Metric m = metric_at (start);
 
 	uint32_t bar_offset = start.bars - m.start().bars;
 
@@ -686,7 +861,7 @@ TempoMap::count_frames_between ( const BBT_Time& start, const BBT_Time& end) con
 		+ start.ticks/Meter::ticks_per_beat;
 
 
-	start_frame = m.frame() + (jack_nframes_t) rint( beat_offset * m.tempo().frames_per_beat(_frame_rate));
+	start_frame = m.frame() + (nframes_t) rint( beat_offset * m.tempo().frames_per_beat(_frame_rate, m.meter()));
 
     	m =  metric_at(end);
 
@@ -695,7 +870,7 @@ TempoMap::count_frames_between ( const BBT_Time& start, const BBT_Time& end) con
 	beat_offset = bar_offset * m.meter().beats_per_bar() - (m.start().beats -1) + (end.beats - 1) 
 		+ end.ticks/Meter::ticks_per_beat;
 
-	end_frame = m.frame() + (jack_nframes_t) rint(beat_offset * m.tempo().frames_per_beat(_frame_rate));
+	end_frame = m.frame() + (nframes_t) rint(beat_offset * m.tempo().frames_per_beat(_frame_rate, m.meter()));
 
 	frames = end_frame - start_frame;
 
@@ -703,12 +878,12 @@ TempoMap::count_frames_between ( const BBT_Time& start, const BBT_Time& end) con
 	
 }	
 
-jack_nframes_t 
+nframes_t 
 TempoMap::count_frames_between_metrics (const Meter& meter, const Tempo& tempo, const BBT_Time& start, const BBT_Time& end) const
 {
-        /*this is used in timestamping the metrics by actually counting the beats */ 
+        /* this is used in timestamping the metrics by actually counting the beats */ 
 
-	jack_nframes_t frames = 0;
+	nframes_t frames = 0;
 	uint32_t bar = start.bars;
 	double beat = (double) start.beats;
 	double beats_counted = 0;
@@ -716,7 +891,7 @@ TempoMap::count_frames_between_metrics (const Meter& meter, const Tempo& tempo,
 	double beat_frames = 0;
 
 	beats_per_bar = meter.beats_per_bar();
-	beat_frames = tempo.frames_per_beat (_frame_rate);
+	beat_frames = tempo.frames_per_beat (_frame_rate,meter);
 
 	frames = 0;
 
@@ -726,24 +901,34 @@ TempoMap::count_frames_between_metrics (const Meter& meter, const Tempo& tempo,
 			beat = 1;
 			++bar;
 			++beats_counted;
-		} else {
-			++beat;
-			++beats_counted;
+
 			if (beat > beats_per_bar) {
+
 				/* this is a fractional beat at the end of a fractional bar
-				   so it should only count for the fraction */
+				   so it should only count for the fraction 
+				*/
+
 				beats_counted -= (ceil(beats_per_bar) - beats_per_bar);
 			}
+
+		} else {
+			++beat;
+			++beats_counted;
 		}
 	}
+
+	// cerr << "Counted " << beats_counted << " from " << start << " to " << end 
+	// << " bpb were " << beats_per_bar 
+	// << " fpb was " << beat_frames
+	// << endl;
 	
-	frames = (jack_nframes_t) floor (beats_counted * beat_frames);
+	frames = (nframes_t) floor (beats_counted * beat_frames);
 
 	return frames;
 	
 }	
 
-jack_nframes_t 
+nframes_t 
 TempoMap::frame_time (const BBT_Time& bbt) const
 {
 	BBT_Time start ; /* 1|1|0 */
@@ -751,27 +936,27 @@ TempoMap::frame_time (const BBT_Time& bbt) const
 	return  count_frames_between ( start, bbt);
 }
 
-jack_nframes_t 
-TempoMap::bbt_duration_at (jack_nframes_t pos, const BBT_Time& bbt, int dir) const
+nframes_t 
+TempoMap::bbt_duration_at (nframes_t pos, const BBT_Time& bbt, int dir) const
 {
-	jack_nframes_t frames = 0;
+	nframes_t frames = 0;
 
 	BBT_Time when;
 	bbt_time(pos,when);
 
 	{
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::ReaderLock lm (lock);
 		frames = bbt_duration_at_unlocked (when, bbt,dir);
 	}
 
 	return frames;
 }
 
-jack_nframes_t 
+nframes_t 
 TempoMap::bbt_duration_at_unlocked (const BBT_Time& when, const BBT_Time& bbt, int dir) const
 {
 
-	jack_nframes_t frames = 0;
+	nframes_t frames = 0;
 
 	double beats_per_bar;
 	BBT_Time result;
@@ -894,80 +1079,57 @@ TempoMap::bbt_duration_at_unlocked (const BBT_Time& when, const BBT_Time& bbt, i
 
 
 
-jack_nframes_t
-TempoMap::round_to_bar (jack_nframes_t fr, int dir)
+nframes_t
+TempoMap::round_to_bar (nframes_t fr, int dir)
 {
-	Glib::Mutex::Lock lm (lock);
-	return round_to_type (fr, dir, Bar);
+        {
+	        Glib::RWLock::ReaderLock lm (lock);
+		return round_to_type (fr, dir, Bar);
+	}
 }
 
 
-jack_nframes_t
-TempoMap::round_to_beat (jack_nframes_t fr, int dir)
+nframes_t
+TempoMap::round_to_beat (nframes_t fr, int dir)
 {
-	Glib::Mutex::Lock lm (lock);
-	return round_to_type (fr, dir, Beat);
+        {
+	        Glib::RWLock::ReaderLock lm (lock);
+		return round_to_type (fr, dir, Beat);
+	}
 }
 
-jack_nframes_t
+nframes_t
 
-TempoMap::round_to_beat_subdivision (jack_nframes_t fr, int sub_num)
+TempoMap::round_to_beat_subdivision (nframes_t fr, int sub_num)
 {
-        Glib::Mutex::Lock lm (lock);
-        TempoMap::BBTPointList::iterator i;
-        TempoMap::BBTPointList *more_zoomed_bbt_points;
-        jack_nframes_t frame_one_beats_worth;
-        jack_nframes_t pos = 0;
-	jack_nframes_t next_pos = 0 ;
-        double tempo = 1;
-        double frames_one_subdivisions_worth;
-        bool fr_has_changed = false;
-
-        int n;
-
-	frame_one_beats_worth = (jack_nframes_t) ::floor ((double)  _frame_rate *  60 / 20 ); //one beat @ 20 bpm
-	more_zoomed_bbt_points = get_points((fr >= frame_one_beats_worth) ? 
-					    fr - frame_one_beats_worth : 0, fr+frame_one_beats_worth );
-
-	if (more_zoomed_bbt_points == 0 || more_zoomed_bbt_points->empty()) {
-		return fr;
-	}
 
-	for (i = more_zoomed_bbt_points->begin(); i != more_zoomed_bbt_points->end(); i++) {
-		if  ((*i).frame <= fr) {
-			pos = (*i).frame;
-			tempo = (*i).tempo->beats_per_minute();
-			
-		} else {
-			i++;
-			next_pos = (*i).frame;
-			break;
-		}
-	}
-	frames_one_subdivisions_worth = ((double) _frame_rate *  60 / (sub_num * tempo));
-
-	for (n = sub_num; n > 0; n--) {
-		if (fr >= (pos + ((n - 0.5) * frames_one_subdivisions_worth))) {
-			fr = (jack_nframes_t) round(pos + (n  * frames_one_subdivisions_worth));
-		 	if (fr > next_pos) {
- 				fr = next_pos;  //take care of fractional beats that don't match the subdivision asked
- 			}
-			fr_has_changed = true;
-			break;
-		}
-	}
+	BBT_Time the_beat;
+	uint32_t ticks_one_half_subdivisions_worth;
+	uint32_t ticks_one_subdivisions_worth;
+
+	bbt_time(fr, the_beat);
+
+	ticks_one_subdivisions_worth = (uint32_t)Meter::ticks_per_beat / sub_num;
+	ticks_one_half_subdivisions_worth = ticks_one_subdivisions_worth / 2;
 
-	if (!fr_has_changed) {
-		fr = pos;
+	if (the_beat.ticks % ticks_one_subdivisions_worth > ticks_one_half_subdivisions_worth) {
+	  uint32_t difference = ticks_one_subdivisions_worth - (the_beat.ticks % ticks_one_subdivisions_worth);
+	  if (the_beat.ticks + difference >= (uint32_t)Meter::ticks_per_beat) {
+	    the_beat.beats++;
+	    the_beat.ticks += difference;
+	    the_beat.ticks -= (uint32_t)Meter::ticks_per_beat;
+	  } else {  
+	    the_beat.ticks += difference;
+	  }
+	} else {
+	  the_beat.ticks -= the_beat.ticks % ticks_one_subdivisions_worth;
 	}
 
-        delete more_zoomed_bbt_points;
-        return fr ;
+	return frame_time (the_beat);
 }
 
-jack_nframes_t
-
-TempoMap::round_to_type (jack_nframes_t frame, int dir, BBTPointType type)
+nframes_t
+TempoMap::round_to_type (nframes_t frame, int dir, BBTPointType type)
 {
 	Metric metric = metric_at (frame);
 	BBT_Time bbt;
@@ -978,16 +1140,16 @@ TempoMap::round_to_type (jack_nframes_t frame, int dir, BBTPointType type)
 	case Bar:
 		if (dir < 0) {
 			/* relax */
-
 		} else if (dir > 0) {
 			if (bbt.beats > 0) {
 				bbt.bars++;
+			} else if (metric.frame() < frame) {
+				bbt.bars++;
 			}
 		} else {
 			if (bbt.beats > metric.meter().beats_per_bar()/2) {
 				bbt.bars++;
 			}
-
 		}
 		bbt.beats = 1;
 		bbt.ticks = 0;
@@ -999,6 +1161,8 @@ TempoMap::round_to_type (jack_nframes_t frame, int dir, BBTPointType type)
 		} else if (dir > 0) {
 			if (bbt.ticks > 0) {
 				bbt.beats++;
+			} else if (metric.frame() < frame) {
+				bbt.beats++;
 			}
 		} else {
 			if (bbt.ticks >= (Meter::ticks_per_beat/2)) {
@@ -1013,12 +1177,17 @@ TempoMap::round_to_type (jack_nframes_t frame, int dir, BBTPointType type)
 		break;
 	
 	}
-
+	
+	/* 
+	cerr << "for " << frame << " round to " << bbt << " using "
+	     << metric.start()
+	     << endl;
+	*/
 	return metric.frame() + count_frames_between (metric.start(), bbt);
 }
 
 TempoMap::BBTPointList *
-TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
+TempoMap::get_points (nframes_t lower, nframes_t upper) const
 {
 
 	Metrics::const_iterator i;
@@ -1030,6 +1199,14 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 	const TempoSection* t;
 	uint32_t bar;
 	uint32_t beat;
+	double beats_per_bar;
+	double beat_frame;
+	double beat_frames;
+	double frames_per_bar;
+	double delta_bars;
+	double delta_beats;
+	double dummy;
+	nframes_t limit;
 
 	meter = &first_meter ();
 	tempo = &first_tempo ();
@@ -1058,6 +1235,10 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 	   Now start generating points.
 	*/
 
+	beats_per_bar = meter->beats_per_bar ();
+	frames_per_bar = meter->frames_per_bar (*tempo, _frame_rate);
+	beat_frames = tempo->frames_per_beat (_frame_rate, *meter);
+	
 	if (meter->frame() > tempo->frame()) {
 		bar = meter->start().bars;
 		beat = meter->start().beats;
@@ -1068,22 +1249,28 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 		current = tempo->frame();
 	}
 
-	points = new BBTPointList;
+	/* initialize current to point to the bar/beat just prior to the
+	   lower frame bound passed in.  assumes that current is initialized
+	   above to be on a beat.
+	*/
+	
+	delta_bars = (lower-current) / frames_per_bar;
+	delta_beats = modf(delta_bars, &dummy) * beats_per_bar;
+	current += (floor(delta_bars) * frames_per_bar) +  (floor(delta_beats) * beat_frames);
 
-	do {
-		double beats_per_bar;
-		double beat_frame;
-		double beat_frames;
-		double frames_per_bar;
-		jack_nframes_t limit;
+	// adjust bars and beats too
+	bar += (uint32_t) (floor(delta_bars));
+	beat += (uint32_t) (floor(delta_beats));
+
+	points = new BBTPointList;
 		
-		beats_per_bar = meter->beats_per_bar ();
-		frames_per_bar = meter->frames_per_bar (*tempo, _frame_rate);
-		beat_frames = tempo->frames_per_beat (_frame_rate);
+	do {
 
 		if (i == metrics->end()) {
 			limit = upper;
+			// cerr << "== limit set to end of request @ " << limit << endl;
 		} else {
+ 			// cerr << "== limit set to next metric @ " << (*i)->frame() << endl;
 			limit = (*i)->frame();
 		}
 
@@ -1095,7 +1282,8 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 
 			if (beat == 1) {
 				if (current >= lower) {
-					points->push_back (BBTPoint (*meter, *tempo,(jack_nframes_t)rint(current), Bar, bar, 1));
+					// cerr << "Add Bar at " << bar << "|1" << " @ " << current << endl;
+					points->push_back (BBTPoint (*meter, *tempo,(nframes_t)rint(current), Bar, bar, 1));
 
 				}
 			}
@@ -1106,7 +1294,8 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 
 			while (beat <= ceil( beats_per_bar) && beat_frame < limit) {
 				if (beat_frame >= lower) {
-					points->push_back (BBTPoint (*meter, *tempo, (jack_nframes_t) rint(beat_frame), Beat, bar, beat));
+					// cerr << "Add Beat at " << bar << '|' << beat << " @ " << beat_frame << endl;
+					points->push_back (BBTPoint (*meter, *tempo, (nframes_t) rint(beat_frame), Beat, bar, beat));
 				}
 				beat_frame += beat_frames;
 				current+= beat_frames;
@@ -1114,7 +1303,11 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 				beat++;
 			}
 
-			if (beat > ceil(beats_per_bar) ) {
+			//  cerr << "out of beats, @ end ? " << (i == metrics->end()) << " out of bpb ? "
+			// << (beat > ceil(beats_per_bar))
+			// << endl;
+
+			if (beat > ceil(beats_per_bar) || i != metrics->end()) {
 
 				/* we walked an entire bar. its
 				   important to move `current' forward
@@ -1132,10 +1325,17 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 				   so we subtract the possible extra fraction from the current
 				*/
 
-				current -=  beat_frames * (ceil(beats_per_bar)-beats_per_bar);
+				if (beat > ceil (beats_per_bar)) {
+					/* next bar goes where the numbers suggest */
+					current -=  beat_frames * (ceil(beats_per_bar)-beats_per_bar);
+					// cerr << "++ next bar from numbers\n";
+				} else {
+					/* next bar goes where the next metric is */
+					current = limit;
+					// cerr << "++ next bar at next metric\n";
+				}
 				bar++;
 				beat = 1;
-
 			} 
 		
 		}
@@ -1160,6 +1360,13 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 				beat = 1;
 			}
 
+			current = (*i)->frame ();
+			// cerr << "loop around with current @ " << current << endl;
+
+			beats_per_bar = meter->beats_per_bar ();
+			frames_per_bar = meter->frames_per_bar (*tempo, _frame_rate);
+			beat_frames = tempo->frames_per_beat (_frame_rate, *meter);
+			
 			++i;
 		}
 
@@ -1168,8 +1375,35 @@ TempoMap::get_points (jack_nframes_t lower, jack_nframes_t upper) const
 	return points;
 }	
 
+const TempoSection&
+TempoMap::tempo_section_at (nframes_t frame)
+{
+	Glib::RWLock::ReaderLock lm (lock);
+	Metrics::iterator i;
+	TempoSection* prev = 0;
+	
+	for (i = metrics->begin(); i != metrics->end(); ++i) {
+		TempoSection* t;
+
+		if ((t = dynamic_cast<TempoSection*> (*i)) != 0) {
+
+			if ((*i)->frame() > frame) {
+				break;
+			}
+
+			prev = t;
+		}
+	}
+
+	if (prev == 0) {
+		fatal << endmsg;
+	}
+
+	return *prev;
+}
+
 const Tempo&
-TempoMap::tempo_at (jack_nframes_t frame)
+TempoMap::tempo_at (nframes_t frame)
 {
 	Metric m (metric_at (frame));
 	return m.tempo();
@@ -1177,7 +1411,7 @@ TempoMap::tempo_at (jack_nframes_t frame)
 
 
 const Meter&
-TempoMap::meter_at (jack_nframes_t frame)
+TempoMap::meter_at (nframes_t frame)
 {
 	Metric m (metric_at (frame));
 	return m.meter();
@@ -1186,12 +1420,14 @@ TempoMap::meter_at (jack_nframes_t frame)
 XMLNode&
 TempoMap::get_state ()
 {
-	Glib::Mutex::Lock lm (lock);
 	Metrics::const_iterator i;
 	XMLNode *root = new XMLNode ("TempoMap");
 
-	for (i = metrics->begin(); i != metrics->end(); ++i) {
-		root->add_child_nocopy ((*i)->get_state());
+	{
+                Glib::RWLock::ReaderLock lm (lock);
+		for (i = metrics->begin(); i != metrics->end(); ++i) {
+		        root->add_child_nocopy ((*i)->get_state());
+		}
 	}
 
 	return *root;
@@ -1201,14 +1437,12 @@ int
 TempoMap::set_state (const XMLNode& node)
 {
 	{
-		Glib::Mutex::Lock lm (lock);
+		Glib::RWLock::WriterLock lm (lock);
 
 		XMLNodeList nlist;
 		XMLNodeConstIterator niter;
 		Metrics old_metrics (*metrics);
 		
-		in_set_state = true;
-		
 		metrics->clear();
 
 		nlist = node.children();
@@ -1246,22 +1480,11 @@ TempoMap::set_state (const XMLNode& node)
 			
 			MetricSectionSorter cmp;
 			metrics->sort (cmp);
-			timestamp_metrics ();
+			timestamp_metrics (true);
 		}
-
-		in_set_state = false;
 	}
 	
-	/* This state needs to be saved. This string will never be a part of the 
-	   object's history though, because the allow_save flag is false during 
-	   session load. This state will eventually be tagged "initial state", 
-	   by a call to StateManager::allow_save from Session::set_state.
-
-	   If this state is not saved, there is no way to reach it through undo actions.
-	*/
-	save_state(_("load XML data"));
-	
-	send_state_changed (Change (0));
+	StateChanged (Change (0));
 
 	return 0;
 }
@@ -1275,7 +1498,7 @@ TempoMap::dump (std::ostream& o) const
 	for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
 
 		if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
-			o << "Tempo @ " << *i << ' ' << t->beats_per_minute() << " BPM at " << t->start() << " frame= " << t->frame() << " (move? "
+			o << "Tempo @ " << *i << ' ' << t->beats_per_minute() << " BPM (denom = " << t->note_type() << ") at " << t->start() << " frame= " << t->frame() << " (move? "
 			  << t->movable() << ')' << endl;
 		} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
 			o << "Meter @ " << *i << ' ' << m->beats_per_bar() << '/' << m->note_divisor() << " at " << m->start() << " frame= " << m->frame() 
@@ -1284,65 +1507,32 @@ TempoMap::dump (std::ostream& o) const
 	}
 }
 
-UndoAction
-TempoMap::get_memento () const
-{
-	return sigc::bind (mem_fun (*(const_cast<TempoMap *> (this)), &StateManager::use_state), _current_state_id);
-}
-
-Change
-TempoMap::restore_state (StateManager::State& state)
+int
+TempoMap::n_tempos() const
 {
-	Glib::Mutex::Lock lm (lock);
-
-	TempoMapState* tmstate = dynamic_cast<TempoMapState*> (&state);
+	Glib::RWLock::ReaderLock lm (lock);
+	int cnt = 0;
 
-	/* We can't just set the metrics pointer to the address of the metrics list 
-	   stored in the state, cause this would ruin this state for restoring in
-	   the future. If they have the same address, they are the same list.
-	   Thus we need to copy all the elements from the state metrics list to the 
-	   current metrics list.
-	*/
-	metrics->clear();
-	for (Metrics::iterator i = tmstate->metrics->begin(); i != tmstate->metrics->end(); ++i) {
-		TempoSection *ts;
-		MeterSection *ms;
-		
-		if ((ts = dynamic_cast<TempoSection*>(*i)) != 0) {
-			metrics->push_back (new TempoSection (*ts));
-		} else if ((ms = dynamic_cast<MeterSection*>(*i)) != 0) {
-			metrics->push_back (new MeterSection (*ms));
+	for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
+		if (dynamic_cast<const TempoSection*>(*i) != 0) {
+			cnt++;
 		}
 	}
-	
-	last_bbt_valid = false;
 
-	return Change (0);
+	return cnt;
 }
 
-StateManager::State* 
-TempoMap::state_factory (std::string why) const
+int
+TempoMap::n_meters() const
 {
-	TempoMapState* state = new TempoMapState (why);
+	Glib::RWLock::ReaderLock lm (lock);
+	int cnt = 0;
 
-	for (Metrics::iterator i = metrics->begin(); i != metrics->end(); ++i) {
-		TempoSection *ts;
-		MeterSection *ms;
-		
-		if ((ts = dynamic_cast<TempoSection*>(*i)) != 0) {
-			state->metrics->push_back (new TempoSection (*ts));
-		} else if ((ms = dynamic_cast<MeterSection*>(*i)) != 0) {
-			state->metrics->push_back (new MeterSection (*ms));
+	for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
+		if (dynamic_cast<const MeterSection*>(*i) != 0) {
+			cnt++;
 		}
 	}
-		
-	return state;
-}
 
-void
-TempoMap::save_state (std::string why)
-{
-	if (!in_set_state) {
-		StateManager::save_state (why);
-	}
+	return cnt;
 }