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livetrax/libs/ardour/tempo.cc
Carl Hetherington 850b7d24a9 Fix comment. Fix believed erroneous add of ticks to a fractional beats value. 
git-svn-id: svn://localhost/ardour2/branches/3.0@8293 d708f5d6-7413-0410-9779-e7cbd77b26cf
2010-12-17 19:20:34 +00:00

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/*
Copyright (C) 2000-2002 Paul Davis
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <algorithm>
#include <stdexcept>
#include <unistd.h>
#include <cmath>
#include <glibmm/thread.h>
#include "pbd/xml++.h"
#include "ardour/debug.h"
#include "ardour/tempo.h"
#include "ardour/utils.h"
#include "i18n.h"
#include <locale.h>
using namespace std;
using namespace ARDOUR;
using namespace PBD;
using Timecode::BBT_Time;
/* _default tempo is 4/4 qtr=120 */
Meter TempoMap::_default_meter (4.0, 4.0);
Tempo TempoMap::_default_tempo (120.0);
double Tempo::frames_per_beat (framecnt_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, framecnt_t sr) const
{
return ((60.0 * sr * _beats_per_bar) / (tempo.beats_per_minute() * _note_type/tempo.note_type()));
}
/***********************************************************************/
const string TempoSection::xml_state_node_name = "Tempo";
TempoSection::TempoSection (const XMLNode& node)
: MetricSection (BBT_Time()), Tempo (TempoMap::default_tempo())
{
const XMLProperty *prop;
BBT_Time start;
LocaleGuard lg (X_("POSIX"));
if ((prop = node.property ("start")) == 0) {
error << _("TempoSection XML node has no \"start\" property") << endmsg;
throw failed_constructor();
}
if (sscanf (prop->value().c_str(), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
&start.bars,
&start.beats,
&start.ticks) < 3) {
error << _("TempoSection XML node has an illegal \"start\" value") << endmsg;
throw failed_constructor();
}
set_start (start);
if ((prop = node.property ("beats-per-minute")) == 0) {
error << _("TempoSection XML node has no \"beats-per-minute\" property") << endmsg;
throw failed_constructor();
}
if (sscanf (prop->value().c_str(), "%lf", &_beats_per_minute) != 1 || _beats_per_minute < 0.0) {
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;
throw failed_constructor();
}
set_movable (string_is_affirmative (prop->value()));
}
XMLNode&
TempoSection::get_state() const
{
XMLNode *root = new XMLNode (xml_state_node_name);
char buf[256];
LocaleGuard lg (X_("POSIX"));
snprintf (buf, sizeof (buf), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
start().bars,
start().beats,
start().ticks);
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);
return *root;
}
/***********************************************************************/
const string MeterSection::xml_state_node_name = "Meter";
MeterSection::MeterSection (const XMLNode& node)
: MetricSection (BBT_Time()), Meter (TempoMap::default_meter())
{
const XMLProperty *prop;
BBT_Time start;
LocaleGuard lg (X_("POSIX"));
if ((prop = node.property ("start")) == 0) {
error << _("MeterSection XML node has no \"start\" property") << endmsg;
throw failed_constructor();
}
if (sscanf (prop->value().c_str(), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
&start.bars,
&start.beats,
&start.ticks) < 3) {
error << _("MeterSection XML node has an illegal \"start\" value") << endmsg;
throw failed_constructor();
}
set_start (start);
if ((prop = node.property ("beats-per-bar")) == 0) {
error << _("MeterSection XML node has no \"beats-per-bar\" property") << endmsg;
throw failed_constructor();
}
if (sscanf (prop->value().c_str(), "%lf", &_beats_per_bar) != 1 || _beats_per_bar < 0.0) {
error << _("MeterSection XML node has an illegal \"beats-per-bar\" value") << endmsg;
throw failed_constructor();
}
if ((prop = node.property ("note-type")) == 0) {
error << _("MeterSection XML node has no \"note-type\" property") << endmsg;
throw failed_constructor();
}
if (sscanf (prop->value().c_str(), "%lf", &_note_type) != 1 || _note_type < 0.0) {
error << _("MeterSection XML node has an illegal \"note-type\" value") << endmsg;
throw failed_constructor();
}
if ((prop = node.property ("movable")) == 0) {
error << _("MeterSection XML node has no \"movable\" property") << endmsg;
throw failed_constructor();
}
set_movable (string_is_affirmative (prop->value()));
}
XMLNode&
MeterSection::get_state() const
{
XMLNode *root = new XMLNode (xml_state_node_name);
char buf[256];
LocaleGuard lg (X_("POSIX"));
snprintf (buf, sizeof (buf), "%" PRIu32 "|%" PRIu32 "|%" PRIu32,
start().bars,
start().beats,
start().ticks);
root->add_property ("start", buf);
snprintf (buf, sizeof (buf), "%f", _note_type);
root->add_property ("note-type", buf);
snprintf (buf, sizeof (buf), "%f", _beats_per_bar);
root->add_property ("beats-per-bar", buf);
snprintf (buf, sizeof (buf), "%s", movable()?"yes":"no");
root->add_property ("movable", buf);
return *root;
}
/***********************************************************************/
struct MetricSectionSorter {
bool operator() (const MetricSection* a, const MetricSection* b) {
return a->start() < b->start();
}
};
TempoMap::TempoMap (framecnt_t fr)
{
metrics = new Metrics;
_frame_rate = fr;
last_bbt_valid = false;
BBT_Time start;
start.bars = 1;
start.beats = 1;
start.ticks = 0;
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);
m->set_movable (false);
/* note: frame time is correct (zero) for both of these */
metrics->push_back (t);
metrics->push_back (m);
}
TempoMap::~TempoMap ()
{
}
int
TempoMap::move_metric_section (MetricSection& section, const BBT_Time& when)
{
if (when == section.start() || !section.movable()) {
return -1;
}
Glib::RWLock::WriterLock lm (lock);
MetricSectionSorter cmp;
if (when.beats != 1) {
/* position by audio frame, then recompute BBT timestamps from the audio ones */
framepos_t frame = frame_time (when);
// cerr << "nominal frame time = " << frame << endl;
framepos_t prev_frame = round_to_type (frame, -1, Beat);
framepos_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);
}
return 0;
}
void
TempoMap::move_tempo (TempoSection& tempo, const BBT_Time& when)
{
if (move_metric_section (tempo, when) == 0) {
PropertyChanged (PropertyChange ());
}
}
void
TempoMap::move_meter (MeterSection& meter, const BBT_Time& when)
{
if (move_metric_section (meter, when) == 0) {
PropertyChanged (PropertyChange ());
}
}
void
TempoMap::remove_tempo (const TempoSection& tempo)
{
bool removed = false;
{
Glib::RWLock::WriterLock lm (lock);
Metrics::iterator i;
for (i = metrics->begin(); i != metrics->end(); ++i) {
if (dynamic_cast<TempoSection*> (*i) != 0) {
if (tempo.frame() == (*i)->frame()) {
if ((*i)->movable()) {
metrics->erase (i);
removed = true;
break;
}
}
}
}
}
if (removed) {
PropertyChanged (PropertyChange ());
}
}
void
TempoMap::remove_meter (const MeterSection& tempo)
{
bool removed = false;
{
Glib::RWLock::WriterLock lm (lock);
Metrics::iterator i;
for (i = metrics->begin(); i != metrics->end(); ++i) {
if (dynamic_cast<MeterSection*> (*i) != 0) {
if (tempo.frame() == (*i)->frame()) {
if ((*i)->movable()) {
metrics->erase (i);
removed = true;
break;
}
}
}
}
}
if (removed) {
PropertyChanged (PropertyChange ());
}
}
void
TempoMap::do_insert (MetricSection* section, bool with_bbt)
{
Metrics::iterator i;
/* Look for any existing MetricSection that is of the same type and
at the same time as the new one, and remove it before adding
the new one.
*/
Metrics::iterator to_remove = metrics->end ();
for (i = metrics->begin(); i != metrics->end(); ++i) {
int const c = (*i)->compare (section, with_bbt);
if (c < 0) {
/* this section is before the one to be added; go back round */
continue;
} else if (c > 0) {
/* this section is after the one to be added; there can't be any at the same time */
break;
}
/* hacky comparison of type */
bool const a = dynamic_cast<TempoSection*> (*i) != 0;
bool const b = dynamic_cast<TempoSection*> (section) != 0;
if (a == b) {
to_remove = i;
break;
}
}
if (to_remove != metrics->end()) {
/* remove the MetricSection at the same time as the one we are about to add */
metrics->erase (to_remove);
}
/* Add the given MetricSection */
for (i = metrics->begin(); i != metrics->end(); ++i) {
if ((*i)->compare (section, with_bbt) < 0) {
continue;
}
metrics->insert (i, section);
break;
}
if (i == metrics->end()) {
metrics->insert (metrics->end(), section);
}
timestamp_metrics (with_bbt);
}
void
TempoMap::add_tempo (const Tempo& tempo, BBT_Time where)
{
{
Glib::RWLock::WriterLock lm (lock);
/* new tempos always start on a beat */
where.ticks = 0;
do_insert (new TempoSection (where, tempo.beats_per_minute(), tempo.note_type()), true);
}
PropertyChanged (PropertyChange ());
}
void
TempoMap::add_tempo (const Tempo& tempo, framepos_t where)
{
{
Glib::RWLock::WriterLock lm (lock);
do_insert (new TempoSection (where, tempo.beats_per_minute(), tempo.note_type()), false);
}
PropertyChanged (PropertyChange ());
}
void
TempoMap::replace_tempo (TempoSection& existing, const Tempo& replacement)
{
bool replaced = false;
{
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;
replaced = true;
timestamp_metrics (true);
break;
}
}
}
if (replaced) {
PropertyChanged (PropertyChange ());
}
}
void
TempoMap::add_meter (const Meter& meter, BBT_Time where)
{
{
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
`where' is based on the existing tempo map, not
the result after we insert the new meter.
*/
if (where.beats != 1) {
where.beats = 1;
where.bars++;
}
/* new meters *always* start on a beat. */
where.ticks = 0;
do_insert (new MeterSection (where, meter.beats_per_bar(), meter.note_divisor()), true);
}
PropertyChanged (PropertyChange ());
}
void
TempoMap::add_meter (const Meter& meter, framepos_t where)
{
{
Glib::RWLock::WriterLock lm (lock);
do_insert (new MeterSection (where, meter.beats_per_bar(), meter.note_divisor()), false);
}
PropertyChanged (PropertyChange ());
}
void
TempoMap::replace_meter (MeterSection& existing, const Meter& replacement)
{
bool replaced = false;
{
Glib::RWLock::WriterLock lm (lock);
Metrics::iterator i;
for (i = metrics->begin(); i != metrics->end(); ++i) {
MeterSection *ms;
if ((ms = dynamic_cast<MeterSection*>(*i)) != 0 && ms == &existing) {
*((Meter*) ms) = replacement;
replaced = true;
timestamp_metrics (true);
break;
}
}
}
if (replaced) {
PropertyChanged (PropertyChange ());
}
}
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;
PropertyChanged (PropertyChange ());
break;
}
}
}
void
TempoMap::change_existing_tempo_at (framepos_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;
PropertyChanged (PropertyChange ());
}
const MeterSection&
TempoMap::first_meter () const
{
const MeterSection *m = 0;
for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
if ((m = dynamic_cast<const MeterSection *> (*i)) != 0) {
return *m;
}
}
fatal << _("programming error: no tempo section in tempo map!") << endmsg;
/*NOTREACHED*/
return *m;
}
const TempoSection&
TempoMap::first_tempo () const
{
const TempoSection *t = 0;
for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
if ((t = dynamic_cast<const TempoSection *> (*i)) != 0) {
return *t;
}
}
fatal << _("programming error: no tempo section in tempo map!") << endmsg;
/*NOTREACHED*/
return *t;
}
void
TempoMap::timestamp_metrics (bool use_bbt)
{
Metrics::iterator i;
const Meter* meter;
const Tempo* tempo;
Meter *m;
Tempo *t;
meter = &first_meter ();
tempo = &first_tempo ();
if (use_bbt) {
// cerr << "\n\n\n ######################\nTIMESTAMP via BBT ##############\n" << endl;
framepos_t current = 0;
framepos_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;
TempoMetric 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
}
bbt_time_with_metric ((*i)->frame(), bbt, metric);
// cerr << "timestamp @ " << (*i)->frame() << " with " << bbt.bars << "|" << bbt.beats << "|" << bbt.ticks << " => ";
if (first) {
first = false;
} else {
if (bbt.ticks > BBT_Time::ticks_per_beat/2) {
/* round up to next beat */
bbt.beats += 1;
}
bbt.ticks = 0;
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;
// 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;
}
TempoMetric
TempoMap::metric_at (framepos_t frame) const
{
TempoMetric m (first_meter(), first_tempo());
const Meter* meter;
const Tempo* tempo;
/* at this point, we are *guaranteed* to have m.meter and m.tempo pointing
at something, because we insert the default tempo and meter during
TempoMap construction.
now see if we can find better candidates.
*/
for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
if ((*i)->frame() > frame) {
break;
}
if ((tempo = dynamic_cast<const TempoSection*>(*i)) != 0) {
m.set_tempo (*tempo);
} else if ((meter = dynamic_cast<const MeterSection*>(*i)) != 0) {
m.set_meter (*meter);
}
m.set_frame ((*i)->frame ());
m.set_start ((*i)->start ());
}
return m;
}
TempoMetric
TempoMap::metric_at (BBT_Time bbt) const
{
TempoMetric m (first_meter(), first_tempo());
const Meter* meter;
const Tempo* tempo;
/* at this point, we are *guaranteed* to have m.meter and m.tempo pointing
at something, because we insert the default tempo and meter during
TempoMap construction.
now see if we can find better candidates.
*/
for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
BBT_Time section_start ((*i)->start());
if (section_start.bars > bbt.bars || (section_start.bars == bbt.bars && section_start.beats > bbt.beats)) {
break;
}
if ((tempo = dynamic_cast<const TempoSection*>(*i)) != 0) {
m.set_tempo (*tempo);
} else if ((meter = dynamic_cast<const MeterSection*>(*i)) != 0) {
m.set_meter (*meter);
}
m.set_frame ((*i)->frame ());
m.set_start (section_start);
}
return m;
}
void
TempoMap::bbt_time (framepos_t frame, BBT_Time& bbt) const
{
{
Glib::RWLock::ReaderLock lm (lock);
bbt_time_unlocked (frame, bbt);
}
}
void
TempoMap::bbt_time_unlocked (framepos_t frame, BBT_Time& bbt) const
{
bbt_time_with_metric (frame, bbt, metric_at (frame));
}
void
TempoMap::bbt_time_with_metric (framepos_t frame, BBT_Time& bbt, const TempoMetric& metric) const
{
framecnt_t frame_diff;
// 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 ticks_per_frame = metric.tempo().frames_per_beat (_frame_rate, metric.meter()) / BBT_Time::ticks_per_beat;
/* now compute how far beyond that point we actually are. */
frame_diff = frame - metric.frame();
bbt.ticks = metric.start().ticks + (uint32_t)round((double)frame_diff / ticks_per_frame);
uint32_t xtra_beats = bbt.ticks / (uint32_t)BBT_Time::ticks_per_beat;
bbt.ticks %= (uint32_t)BBT_Time::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(BBT_Time::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;
}
framecnt_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 be "legal" BBT types,
that means that the beats and ticks should be inside a bar
*/
framecnt_t frames = 0;
framepos_t start_frame = 0;
framepos_t end_frame = 0;
TempoMetric m = metric_at (start);
uint32_t bar_offset = start.bars - m.start().bars;
double beat_offset = bar_offset*m.meter().beats_per_bar() - (m.start().beats-1) + (start.beats -1)
+ start.ticks/BBT_Time::ticks_per_beat;
start_frame = m.frame() + (framepos_t) rint( beat_offset * m.tempo().frames_per_beat(_frame_rate, m.meter()));
m = metric_at(end);
bar_offset = end.bars - m.start().bars;
beat_offset = bar_offset * m.meter().beats_per_bar() - (m.start().beats -1) + (end.beats - 1)
+ end.ticks/BBT_Time::ticks_per_beat;
end_frame = m.frame() + (framepos_t) rint(beat_offset * m.tempo().frames_per_beat(_frame_rate, m.meter()));
frames = end_frame - start_frame;
return frames;
}
framecnt_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 */
framecnt_t frames = 0;
uint32_t bar = start.bars;
double beat = (double) start.beats;
double beats_counted = 0;
double beats_per_bar = 0;
double beat_frames = 0;
beats_per_bar = meter.beats_per_bar();
beat_frames = tempo.frames_per_beat (_frame_rate,meter);
frames = 0;
while (bar < end.bars || (bar == end.bars && beat < end.beats)) {
if (beat >= beats_per_bar) {
beat = 1;
++bar;
++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
*/
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 = (framecnt_t) llrint (floor (beats_counted * beat_frames));
return frames;
}
framepos_t
TempoMap::frame_time (const BBT_Time& bbt) const
{
BBT_Time start ; /* 1|1|0 */
return count_frames_between ( start, bbt);
}
framecnt_t
TempoMap::bbt_duration_at (framepos_t pos, const BBT_Time& bbt, int dir) const
{
framecnt_t frames = 0;
BBT_Time when;
bbt_time(pos, when);
{
Glib::RWLock::ReaderLock lm (lock);
frames = bbt_duration_at_unlocked (when, bbt,dir);
}
return frames;
}
framecnt_t
TempoMap::bbt_duration_at_unlocked (const BBT_Time& when, const BBT_Time& bbt, int dir) const
{
framecnt_t frames = 0;
double beats_per_bar;
BBT_Time result;
result.bars = max(1U, when.bars + dir * bbt.bars) ;
result.beats = 1;
result.ticks = 0;
TempoMetric metric = metric_at(result);
beats_per_bar = metric.meter().beats_per_bar();
/*reduce things to legal bbt values
we have to handle possible fractional=shorter beats at the end of measures
and things like 0|11|9000 as a duration in a 4.5/4 measure
the musical decision is that the fractional beat is also a beat , although a shorter one
*/
if (dir >= 0) {
result.beats = when.beats + bbt.beats;
result.ticks = when.ticks + bbt.ticks;
while (result.beats >= (beats_per_bar + 1)) {
result.bars++;
result.beats -= (uint32_t) ceil(beats_per_bar);
metric = metric_at(result); // maybe there is a meter change
beats_per_bar = metric.meter().beats_per_bar();
}
/*we now counted the beats and landed in the target measure, now deal with ticks
this seems complicated, but we want to deal with the corner case of a sequence of time signatures like 0.2/4-0.7/4
and with request like bbt = 3|2|9000 ,so we repeat the same loop but add ticks
*/
/* of course gtk_ardour only allows bar with at least 1.0 beats .....
*/
uint32_t ticks_at_beat = (uint32_t) ( result.beats == ceil(beats_per_bar) ?
(1 - (ceil(beats_per_bar) - beats_per_bar))* BBT_Time::ticks_per_beat
: BBT_Time::ticks_per_beat );
while (result.ticks >= ticks_at_beat) {
result.beats++;
result.ticks -= ticks_at_beat;
if (result.beats >= (beats_per_bar + 1)) {
result.bars++;
result.beats = 1;
metric = metric_at(result); // maybe there is a meter change
beats_per_bar = metric.meter().beats_per_bar();
}
ticks_at_beat= (uint32_t) ( result.beats == ceil(beats_per_bar) ?
(1 - (ceil(beats_per_bar) - beats_per_bar) ) * BBT_Time::ticks_per_beat
: BBT_Time::ticks_per_beat);
}
} else {
uint32_t b = bbt.beats;
/* count beats */
while( b > when.beats ) {
result.bars = max(1U,result.bars-- ) ;
metric = metric_at(result); // maybe there is a meter change
beats_per_bar = metric.meter().beats_per_bar();
if (b >= ceil(beats_per_bar)) {
b -= (uint32_t) ceil(beats_per_bar);
} else {
b = (uint32_t) ceil(beats_per_bar) - b + when.beats ;
}
}
result.beats = when.beats - b;
/*count ticks */
if (bbt.ticks <= when.ticks) {
result.ticks = when.ticks - bbt.ticks;
} else {
uint32_t ticks_at_beat= (uint32_t) BBT_Time::ticks_per_beat;
uint32_t t = bbt.ticks - when.ticks;
do {
if (result.beats == 1) {
result.bars = max(1U, result.bars-- ) ;
metric = metric_at(result); // maybe there is a meter change
beats_per_bar = metric.meter().beats_per_bar();
result.beats = (uint32_t) ceil(beats_per_bar);
ticks_at_beat = (uint32_t) ((1 - (ceil(beats_per_bar) - beats_per_bar)) * BBT_Time::ticks_per_beat) ;
} else {
result.beats --;
ticks_at_beat = (uint32_t) BBT_Time::ticks_per_beat;
}
if (t <= ticks_at_beat) {
result.ticks = ticks_at_beat - t;
} else {
t-= ticks_at_beat;
}
} while (t > ticks_at_beat);
}
}
if (dir < 0 ) {
frames = count_frames_between( result,when);
} else {
frames = count_frames_between(when,result);
}
return frames;
}
framepos_t
TempoMap::round_to_bar (framepos_t fr, int dir)
{
{
Glib::RWLock::ReaderLock lm (lock);
return round_to_type (fr, dir, Bar);
}
}
framepos_t
TempoMap::round_to_beat (framepos_t fr, int dir)
{
{
Glib::RWLock::ReaderLock lm (lock);
return round_to_type (fr, dir, Beat);
}
}
framepos_t
TempoMap::round_to_beat_subdivision (framepos_t fr, int sub_num, int dir)
{
BBT_Time the_beat;
uint32_t ticks_one_half_subdivisions_worth;
uint32_t ticks_one_subdivisions_worth;
uint32_t difference;
bbt_time(fr, the_beat);
ticks_one_subdivisions_worth = (uint32_t)BBT_Time::ticks_per_beat / sub_num;
ticks_one_half_subdivisions_worth = ticks_one_subdivisions_worth / 2;
if (dir > 0) {
/* round to next */
uint32_t mod = the_beat.ticks % ticks_one_subdivisions_worth;
if (mod == 0) {
/* right on the subdivision, so the difference is just the subdivision ticks */
difference = ticks_one_subdivisions_worth;
} else {
/* not on subdivision, compute distance to next subdivision */
difference = ticks_one_subdivisions_worth - mod;
}
the_beat = bbt_add (the_beat, BBT_Time (0, 0, difference));
} else if (dir < 0) {
/* round to previous */
uint32_t mod = the_beat.ticks % ticks_one_subdivisions_worth;
if (mod == 0) {
/* right on the subdivision, so the difference is just the subdivision ticks */
difference = ticks_one_subdivisions_worth;
} else {
/* not on subdivision, compute distance to previous subdivision, which
is just the modulus.
*/
difference = mod;
}
try {
the_beat = bbt_subtract (the_beat, BBT_Time (0, 0, difference));
} catch (...) {
/* can't go backwards from wherever pos is, so just return it */
return fr;
}
} else {
/* round to nearest */
if (the_beat.ticks % ticks_one_subdivisions_worth > ticks_one_half_subdivisions_worth) {
difference = ticks_one_subdivisions_worth - (the_beat.ticks % ticks_one_subdivisions_worth);
the_beat = bbt_add (the_beat, BBT_Time (0, 0, difference));
} else {
// difference = ticks_one_subdivisions_worth - (the_beat.ticks % ticks_one_subdivisions_worth);
the_beat.ticks -= the_beat.ticks % ticks_one_subdivisions_worth;
}
}
return frame_time (the_beat);
}
framepos_t
TempoMap::round_to_type (framepos_t frame, int dir, BBTPointType type)
{
TempoMetric metric = metric_at (frame);
BBT_Time bbt;
BBT_Time start;
BBT_Time one_bar (1,0,0);
BBT_Time one_beat (0,1,0);
bbt_time_with_metric (frame, bbt, metric);
switch (type) {
case Bar:
DEBUG_TRACE(DEBUG::SnapBBT, string_compose ("round from %1 (%3) to bars in direction %2\n", frame, dir, bbt));
if (dir < 0) {
/* find bar position preceding frame */
try {
bbt = bbt_subtract (bbt, one_bar);
}
catch (...) {
return frame;
}
} else if (dir > 0) {
/* find bar position following frame */
try {
bbt = bbt_add (bbt, one_bar, metric);
}
catch (...) {
return frame;
}
} else {
/* "true" rounding */
float midbar_beats;
float midbar_ticks;
midbar_beats = metric.meter().beats_per_bar() / 2 + 1;
midbar_ticks = BBT_Time::ticks_per_beat * fmod (midbar_beats, 1.0f);
midbar_beats = floor (midbar_beats);
BBT_Time midbar (bbt.bars, lrintf (midbar_beats), lrintf (midbar_ticks));
if (bbt < midbar) {
/* round down */
bbt.beats = 1;
bbt.ticks = 0;
} else {
/* round up */
bbt.bars++;
bbt.beats = 1;
bbt.ticks = 0;
}
}
/* force beats & ticks to their values at the start of a bar */
bbt.beats = 1;
bbt.ticks = 0;
break;
case Beat:
DEBUG_TRACE(DEBUG::SnapBBT, string_compose ("round from %1 (%3) to beat in direction %2\n", frame, (dir < 0 ? "back" : "forward"), bbt));
if (dir < 0) {
/* find beat position preceding frame */
try {
bbt = bbt_subtract (bbt, one_beat);
}
catch (...) {
return frame;
}
} else if (dir > 0) {
/* find beat position following frame */
try {
bbt = bbt_add (bbt, one_beat, metric);
}
catch (...) {
return frame;
}
} else {
/* "true" rounding */
/* round to nearest beat */
if (bbt.ticks >= (BBT_Time::ticks_per_beat/2)) {
try {
bbt = bbt_add (bbt, one_beat, metric);
}
catch (...) {
return frame;
}
}
}
/* force ticks to the value at the start of a beat */
bbt.ticks = 0;
break;
}
DEBUG_TRACE(DEBUG::SnapBBT, string_compose ("\tat %1 count frames from %2 to %3 = %4\n", metric.frame(), metric.start(), bbt, count_frames_between (metric.start(), bbt)));
return metric.frame() + count_frames_between (metric.start(), bbt);
}
TempoMap::BBTPointList *
TempoMap::get_points (framepos_t lower, framepos_t upper) const
{
Metrics::const_iterator i;
BBTPointList *points;
double current;
const MeterSection* meter;
const MeterSection* m;
const TempoSection* tempo;
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;
framepos_t limit;
meter = &first_meter ();
tempo = &first_tempo ();
/* find the starting point */
for (i = metrics->begin(); i != metrics->end(); ++i) {
if ((*i)->frame() > lower) {
break;
}
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
}
}
/* We now have:
meter -> the Meter for "lower"
tempo -> the Tempo for "lower"
i -> for first new metric after "lower", possibly metrics->end()
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;
current = meter->frame();
} else {
bar = tempo->start().bars;
beat = tempo->start().beats;
current = tempo->frame();
}
/* 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);
// adjust bars and beats too
bar += (uint32_t) (floor(delta_bars));
beat += (uint32_t) (floor(delta_beats));
points = new BBTPointList;
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();
}
limit = min (limit, upper);
while (current < limit) {
/* if we're at the start of a bar, add bar point */
if (beat == 1) {
if (current >= lower) {
// cerr << "Add Bar at " << bar << "|1" << " @ " << current << endl;
points->push_back (BBTPoint (*meter, *tempo,(framepos_t)rint(current), Bar, bar, 1));
}
}
/* add some beats if we can */
beat_frame = current;
while (beat <= ceil( beats_per_bar) && beat_frame < limit) {
if (beat_frame >= lower) {
// cerr << "Add Beat at " << bar << '|' << beat << " @ " << beat_frame << endl;
points->push_back (BBTPoint (*meter, *tempo, (framepos_t) rint(beat_frame), Beat, bar, beat));
}
beat_frame += beat_frames;
current+= beat_frames;
beat++;
}
// 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
by the actual frames_per_bar, not move it to
an integral beat_frame, so that metrics with
non-integral beats-per-bar have
their bar positions set
correctly. consider a metric with
9-1/2 beats-per-bar. the bar we
just filled had 10 beat marks,
but the bar end is 1/2 beat before
the last beat mark.
And it is also possible that a tempo
change occured in the middle of a bar,
so we subtract the possible extra fraction from the current
*/
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;
}
}
/* if we're done, then we're done */
if (current >= upper) {
break;
}
/* i is an iterator that refers to the next metric (or none).
if there is a next metric, move to it, and continue.
*/
if (i != metrics->end()) {
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
/* new MeterSection, beat always returns to 1 */
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;
}
} while (1);
return points;
}
const TempoSection&
TempoMap::tempo_section_at (framepos_t frame) const
{
Glib::RWLock::ReaderLock lm (lock);
Metrics::const_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 (framepos_t frame) const
{
TempoMetric m (metric_at (frame));
return m.tempo();
}
const Meter&
TempoMap::meter_at (framepos_t frame) const
{
TempoMetric m (metric_at (frame));
return m.meter();
}
XMLNode&
TempoMap::get_state ()
{
Metrics::const_iterator i;
XMLNode *root = new XMLNode ("TempoMap");
{
Glib::RWLock::ReaderLock lm (lock);
for (i = metrics->begin(); i != metrics->end(); ++i) {
root->add_child_nocopy ((*i)->get_state());
}
}
return *root;
}
int
TempoMap::set_state (const XMLNode& node, int /*version*/)
{
{
Glib::RWLock::WriterLock lm (lock);
XMLNodeList nlist;
XMLNodeConstIterator niter;
Metrics old_metrics (*metrics);
metrics->clear();
nlist = node.children();
for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
XMLNode* child = *niter;
if (child->name() == TempoSection::xml_state_node_name) {
try {
metrics->push_back (new TempoSection (*child));
}
catch (failed_constructor& err){
error << _("Tempo map: could not set new state, restoring old one.") << endmsg;
*metrics = old_metrics;
break;
}
} else if (child->name() == MeterSection::xml_state_node_name) {
try {
metrics->push_back (new MeterSection (*child));
}
catch (failed_constructor& err) {
error << _("Tempo map: could not set new state, restoring old one.") << endmsg;
*metrics = old_metrics;
break;
}
}
}
if (niter == nlist.end()) {
MetricSectionSorter cmp;
metrics->sort (cmp);
timestamp_metrics (true);
}
}
PropertyChanged (PropertyChange ());
return 0;
}
void
TempoMap::dump (std::ostream& o) const
{
const MeterSection* m;
const TempoSection* t;
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 (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()
<< " (move? " << m->movable() << ')' << endl;
}
}
}
int
TempoMap::n_tempos() const
{
Glib::RWLock::ReaderLock lm (lock);
int cnt = 0;
for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
if (dynamic_cast<const TempoSection*>(*i) != 0) {
cnt++;
}
}
return cnt;
}
int
TempoMap::n_meters() const
{
Glib::RWLock::ReaderLock lm (lock);
int cnt = 0;
for (Metrics::const_iterator i = metrics->begin(); i != metrics->end(); ++i) {
if (dynamic_cast<const MeterSection*>(*i) != 0) {
cnt++;
}
}
return cnt;
}
void
TempoMap::insert_time (framepos_t where, framecnt_t amount)
{
for (Metrics::iterator i = metrics->begin(); i != metrics->end(); ++i) {
if ((*i)->frame() >= where) {
(*i)->set_frame ((*i)->frame() + amount);
}
}
timestamp_metrics (false);
PropertyChanged (PropertyChange ());
}
BBT_Time
TempoMap::bbt_add (const BBT_Time& start, const BBT_Time& other) const
{
TempoMetric metric = metric_at (start);
return bbt_add (start, other, metric);
}
/**
* add the BBT interval @param increment to @param start and return the result
*/
BBT_Time
TempoMap::bbt_add (const BBT_Time& start, const BBT_Time& increment, const TempoMetric& /*metric*/) const
{
BBT_Time result = start;
BBT_Time op = increment; /* argument is const, but we need to modify it */
uint32_t ticks = result.ticks + op.ticks;
if (ticks >= BBT_Time::ticks_per_beat) {
op.beats++;
result.ticks = ticks % (uint32_t) BBT_Time::ticks_per_beat;
} else {
result.ticks += op.ticks;
}
/* now comes the complicated part. we have to add one beat a time,
checking for a new metric on every beat.
*/
/* grab all meter sections */
list<const MeterSection*> meter_sections;
for (Metrics::const_iterator x = metrics->begin(); x != metrics->end(); ++x) {
const MeterSection* ms;
if ((ms = dynamic_cast<const MeterSection*>(*x)) != 0) {
meter_sections.push_back (ms);
}
}
assert (!meter_sections.empty());
list<const MeterSection*>::const_iterator next_meter;
const Meter* meter = 0;
/* go forwards through the meter sections till we get to the one
covering the current value of result. this positions i to point to
the next meter section too, or the end.
*/
for (next_meter = meter_sections.begin(); next_meter != meter_sections.end(); ++next_meter) {
if (result < (*next_meter)->start()) {
/* this metric is past the result time. stop looking, we have what we need */
break;
}
if (result == (*next_meter)->start()) {
/* this meter section starts at result, push i beyond it so that it points
to the NEXT section, opwise we will get stuck later, and use this meter section.
*/
meter = *next_meter;
++next_meter;
break;
}
meter = *next_meter;
}
assert (meter != 0);
/* OK, now have the meter for the bar start we are on, and i is an iterator
that points to the metric after the one we are currently dealing with
(or to metrics->end(), of course)
*/
while (op.beats) {
/* given the current meter, have we gone past the end of the bar ? */
if (result.beats >= meter->beats_per_bar()) {
/* move to next bar, first beat */
result.bars++;
result.beats = 1;
} else {
result.beats++;
}
/* one down ... */
op.beats--;
/* check if we need to use a new meter section: has adding beats to result taken us
to or after the start of the next meter section? in which case, use it.
*/
if (next_meter != meter_sections.end() && (((*next_meter)->start () < result) || (result == (*next_meter)->start()))) {
meter = *next_meter;
++next_meter;
}
}
/* finally, add bars */
result.bars += op.bars++;
return result;
}
/**
* subtract the BBT interval @param decrement from @param start and return the result
*/
BBT_Time
TempoMap::bbt_subtract (const BBT_Time& start, const BBT_Time& decrement) const
{
BBT_Time result = start;
BBT_Time op = decrement; /* argument is const, but we need to modify it */
if (op.ticks > result.ticks) {
/* subtract an extra beat later; meanwhile set ticks to the right "carry" value */
op.beats++;
result.ticks = BBT_Time::ticks_per_beat - (op.ticks - result.ticks);
} else {
result.ticks -= op.ticks;
}
/* now comes the complicated part. we have to subtract one beat a time,
checking for a new metric on every beat.
*/
/* grab all meter sections */
list<const MeterSection*> meter_sections;
for (Metrics::const_iterator x = metrics->begin(); x != metrics->end(); ++x) {
const MeterSection* ms;
if ((ms = dynamic_cast<const MeterSection*>(*x)) != 0) {
meter_sections.push_back (ms);
}
}
assert (!meter_sections.empty());
/* go backwards through the meter sections till we get to the one
covering the current value of result. this positions i to point to
the next (previous) meter section too, or the end.
*/
const MeterSection* meter = 0;
list<const MeterSection*>::reverse_iterator next_meter; // older versions of GCC don't
// support const_reverse_iterator::operator!=()
for (next_meter = meter_sections.rbegin(); next_meter != meter_sections.rend(); ++next_meter) {
/* when we find the first meter section that is before or at result, use it,
and set next_meter to the previous one
*/
if ((*next_meter)->start() < result || (*next_meter)->start() == result) {
meter = *next_meter;
++next_meter;
break;
}
}
assert (meter != 0);
/* OK, now have the meter for the bar start we are on, and i is an iterator
that points to the metric after the one we are currently dealing with
(or to metrics->end(), of course)
*/
while (op.beats) {
/* have we reached the start of the bar? if so, move to the last beat of the previous
bar. opwise, just step back 1 beat.
*/
if (result.beats == 1) {
/* move to previous bar, last beat */
if (result.bars <= 1) {
/* i'm sorry dave, i can't do that */
throw std::out_of_range ("illegal BBT subtraction");
}
result.bars--;
result.beats = meter->beats_per_bar();
} else {
/* back one beat */
result.beats--;
}
/* one down ... */
op.beats--;
/* check if we need to use a new meter section: has subtracting beats to result taken us
to before the start of the current meter section? in which case, use the prior one.
*/
if (result < meter->start() && next_meter != meter_sections.rend()) {
meter = *next_meter;
++next_meter;
}
}
/* finally, subtract bars */
if (op.bars >= result.bars) {
/* i'm sorry dave, i can't do that */
throw std::out_of_range ("illegal BBT subtraction");
}
result.bars -= op.bars;
return result;
}
/** Add the BBT interval op to pos and return the result */
framepos_t
TempoMap::framepos_plus_bbt (framepos_t pos, BBT_Time op) const
{
Metrics::const_iterator i;
const MeterSection* meter;
const MeterSection* m;
const TempoSection* tempo;
const TempoSection* t;
framecnt_t frames_per_beat;
meter = &first_meter ();
tempo = &first_tempo ();
assert (meter);
assert (tempo);
/* find the starting metrics for tempo & meter */
for (i = metrics->begin(); i != metrics->end(); ++i) {
if ((*i)->frame() > pos) {
break;
}
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
}
}
/* We now have:
meter -> the Meter for "pos"
tempo -> the Tempo for "pos"
i -> for first new metric after "pos", possibly metrics->end()
*/
/* now comes the complicated part. we have to add one beat a time,
checking for a new metric on every beat.
*/
frames_per_beat = tempo->frames_per_beat (_frame_rate, *meter);
while (op.bars) {
pos += llrint (frames_per_beat * meter->beats_per_bar());
op.bars--;
/* check if we need to use a new metric section: has adding frames moved us
to or after the start of the next metric section? in which case, use it.
*/
if (i != metrics->end()) {
if ((*i)->frame() <= pos) {
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
}
++i;
frames_per_beat = tempo->frames_per_beat (_frame_rate, *meter);
}
}
}
while (op.beats) {
/* given the current meter, have we gone past the end of the bar ? */
pos += frames_per_beat;
op.beats--;
/* check if we need to use a new metric section: has adding frames moved us
to or after the start of the next metric section? in which case, use it.
*/
if (i != metrics->end()) {
if ((*i)->frame() <= pos) {
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
}
++i;
frames_per_beat = tempo->frames_per_beat (_frame_rate, *meter);
}
}
}
if (op.ticks) {
if (op.ticks >= BBT_Time::ticks_per_beat) {
pos += frames_per_beat;
pos += llrint (frames_per_beat * ((op.ticks % (uint32_t) BBT_Time::ticks_per_beat) / (double) BBT_Time::ticks_per_beat));
} else {
pos += llrint (frames_per_beat * (op.ticks / (double) BBT_Time::ticks_per_beat));
}
}
return pos;
}
/** Count the number of beats that are equivalent to distance when starting at pos */
double
TempoMap::framewalk_to_beats (framepos_t pos, framecnt_t distance) const
{
Metrics::const_iterator i;
double beats = 0;
const MeterSection* meter;
const MeterSection* m;
const TempoSection* tempo;
const TempoSection* t;
double frames_per_beat;
double ddist = distance;
double dpos = pos;
meter = &first_meter ();
tempo = &first_tempo ();
assert (meter);
assert (tempo);
/* find the starting metrics for tempo & meter */
for (i = metrics->begin(); i != metrics->end(); ++i) {
if ((*i)->frame() > pos) {
break;
}
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
}
}
/* We now have:
meter -> the Meter for "pos"
tempo -> the Tempo for "pos"
i -> for first new metric after "pos", possibly metrics->end()
*/
/* now comes the complicated part. we have to add one beat a time,
checking for a new metric on every beat.
*/
frames_per_beat = tempo->frames_per_beat (_frame_rate, *meter);
while (ddist > 0) {
/* if we're nearly at the end, but have a fractional beat left,
compute the fraction and then its all over
*/
if (ddist < frames_per_beat) {
beats += ddist / frames_per_beat;
break;
}
/* walk one beat */
ddist -= frames_per_beat;
dpos += frames_per_beat;
beats += 1.0;
/* check if we need to use a new metric section: has adding frames moved us
to or after the start of the next metric section? in which case, use it.
*/
if (i != metrics->end()) {
if ((*i)->frame() <= (framepos_t) dpos) {
if ((t = dynamic_cast<const TempoSection*>(*i)) != 0) {
tempo = t;
} else if ((m = dynamic_cast<const MeterSection*>(*i)) != 0) {
meter = m;
}
++i;
frames_per_beat = tempo->frames_per_beat (_frame_rate, *meter);
}
}
}
return beats;
}
/** Compare the time of this with that of another MetricSection.
* @param with_bbt True to compare using ::start(), false to use ::frame().
* @return -1 for less than, 0 for equal, 1 for greater than.
*/
int
MetricSection::compare (MetricSection* other, bool with_bbt) const
{
if (with_bbt) {
if (start() == other->start()) {
return 0;
} else if (start() < other->start()) {
return -1;
} else {
return 1;
}
} else {
if (frame() == other->frame()) {
return 0;
} else if (frame() < other->frame()) {
return -1;
} else {
return 1;
}
}
/* NOTREACHED */
return 0;
}
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