//---------------------------------------------------------------------------------------
NoteTypeAndDots duration_to_note_type_and_dots(TimeUnits duration)
{
//determine type
int type = k_256th;
if (is_lower_time(duration, 2.0))
type = k_256th;
else if (is_lower_time(duration, 4.0))
type = k_128th;
else if (is_lower_time(duration, 8.0))
type = k_64th;
else if (is_lower_time(duration, 16.0))
type = k_32nd;
else if (is_lower_time(duration, 32.0))
type = k_16th;
else if (is_lower_time(duration, 64.0))
type = k_eighth;
else if (is_lower_time(duration, 128.0))
type = k_quarter;
else if (is_lower_time(duration, 256.0))
type = k_half;
else if (is_lower_time(duration, 512.0))
type = k_whole;
else if (is_lower_time(duration, 1024.0))
type = k_breve;
else
type = k_longa;
//compute dots
TimeUnits base = to_duration(type, 0);
duration -= to_duration(type, 0);
double factor = 1.0 + duration / base;
if (factor < 1.25)
return NoteTypeAndDots(type, 0);
if (factor < 1.625)
return NoteTypeAndDots(type, 1);
if (factor < 1.8125)
return NoteTypeAndDots(type, 2);
if (factor < 1.90625)
return NoteTypeAndDots(type, 3);
if (factor < 1.953125)
return NoteTypeAndDots(type, 4);
if (factor < 1.9765625)
return NoteTypeAndDots(type, 5);
if (factor < 1.98828125)
return NoteTypeAndDots(type, 6);
if (factor < 1.99414063)
return NoteTypeAndDots(type, 7);
if (factor < 1.99707031)
return NoteTypeAndDots(type, 8);
else
return NoteTypeAndDots(type, 9);
}
//---------------------------------------------------------------------------------------
int get_beat_position(TimeUnits timePos, ImoTimeSignature* pTS)
{
// Some times it is necessary to know the type of beat (strong, medium, weak,
// off-beat) at which a note or rest is positioned.
// This function receives the time for a note/rest and the current time signature
// and returns the type of beat: either an integer positive value 0..n, meaning
// 'on-beat', where n is the beat number, or -1 meaning 'off-beat'
int beatType = pTS->get_bottom_number();
// coumpute beat duration
int beatDuration;
switch (beatType)
{
case 1: beatDuration = int( to_duration(k_whole, 0) ); break;
case 2: beatDuration = int( to_duration(k_half, 0) ); break;
case 4: beatDuration = int( to_duration(k_quarter, 0) ); break;
case 8: beatDuration = 3 * int( to_duration(k_eighth, 0) ); break;
case 16: beatDuration = int( to_duration(k_eighth, 0) ); break;
default:
{
string msg = str( boost::format("[get_beat_position] BeatType %d unknown.")
% beatType );
LOMSE_LOG_ERROR(msg);
throw runtime_error(msg);
}
}
// compute relative position of this note/rest with reference to the beat
int beatNum = int(timePos) / beatDuration; //number of beat
TimeUnits beatShift = fabs(timePos - TimeUnits(beatDuration * beatNum));
if (beatShift < 1.0)
//on-beat
return beatNum;
else
// off-beat
return k_off_beat;
}
void thread::sleep(const xtime& xt)
{
for (int foo=0; foo < 5; ++foo)
{
#if defined(BOOST_HAS_WINTHREADS)
int milliseconds;
to_duration(xt, milliseconds);
Sleep(milliseconds);
#elif defined(BOOST_HAS_PTHREADS)
# if defined(BOOST_HAS_PTHREAD_DELAY_NP)
timespec ts;
to_timespec_duration(xt, ts);
int res = 0;
res = pthread_delay_np(&ts);
assert(res == 0);
# elif defined(BOOST_HAS_NANOSLEEP)
timespec ts;
to_timespec_duration(xt, ts);
// nanosleep takes a timespec that is an offset, not
// an absolute time.
nanosleep(&ts, 0);
# else
mutex mx;
mutex::scoped_lock lock(mx);
condition cond;
cond.timed_wait(lock, xt);
# endif
#elif defined(BOOST_HAS_MPTASKS)
int microseconds;
to_microduration(xt, microseconds);
Duration lMicroseconds(kDurationMicrosecond * microseconds);
AbsoluteTime sWakeTime(DurationToAbsolute(lMicroseconds));
threads::mac::detail::safe_delay_until(&sWakeTime);
#endif
xtime cur;
xtime_get(&cur, TIME_UTC);
if (xtime_cmp(xt, cur) <= 0)
return;
}
}