Cyclic
sound-objects
Any
sound-object may contain a periodical part starting at an arbitrary point of
its time-span interval. Clicking the "Period (cyclic object)/strike mode"
button on the dialog shown Fig.2 displays a dialog for declaring periodicity.
Cyclic
sound-objects
are handled in a particular way: if their dilation ratio in the performance
(see §3.1) is larger than 2, they are repeated instead of being dilated.
An example is given with "-da.prerol
l".
The item
{C6
B5 A5 G5 A5 B5 C6, cycle1}
contains
'cycle1', a sound-object which has a periodical part in the last 60% of its
time-span interval. The resulting time setting is shown Fig.6. The
non-periodical part (40% of the duration) is first performed, then the
periodical part is repeated 7 times in synchronisation with the sequence of
simple notes.
Fig.6
A performance with a cyclic sound-object
Note
that the pivot of 'cycle1'is set at the beginning of its periodical part to
ensure its proper location.
There
are two typical cases of periodicity, both handled by BP2:
• The
sequence of events in the periodical part must be sent again to the sound
device when that part is repeated. This happens for instance with sound-objects
handled by a MIDI synthesizer.
• The
object is declared cyclic but there is no need to repeat the sequence in the
periodical part. This happens with sound-objects handled by a MIDI sampler. The
sampler expects BP2 to trigger the process with a NoteOn and then it takes care
of repetitions until a NoteOff is received.
In
the latter case, property "Discard NoteOff's except in last perio
d"
should be activated. It prevents the sampler from setting off as soon as the
first cycle has been completed. This property is generally completed with
"Don't strike again NoteOn'
s"
accessed in the same dialog and documented on-line.
Property
"Force integer number of period
s"
adjusts the durations of sound-objects to make sure that the last repetition of
the periodical part will be complete. It is only required in case the
acceptable dilation rati
o
of the sound-object (see reference manual §3.1) is less than 2.