Description

Schedules a new instrument nstance, returning a handle that can be used later to refer directly to the running nstance. This opcode is similar to schedule, but has the added facility of retrieving the nstance handle.

Syntax

iHandle nstance insnum, iwhen, idur [, ip4] [, ip5] [...]

iHandle nstance "insname", iwhen, idur [, ip4] [, ip5] [...]

Initialization

iHandle -- this variable will contain a handle to the event instance. It can be used, for example, to stop the given instrument instance via the turnoff opcode. Note that the instance handle is only valid once the instrument is initialised.

insnum -- instrument number. Equivalent to p1 in a score i statement. insnum must be a number greater than the number of the calling instrument.

“insname” -- A string (in double-quotes) representing a named instrument.

iwhen -- start time of the new event. Equivalent to p2 in a score i statement. iwhen must be nonnegative. If iwhen is zero, insum must be greater than or equal to the p1 of the current instrument.

idur -- duration of event. Equivalent to p3 in a score i statement.

ip4, ip5, ... -- Equivalent to p4, p5, etc., in a score i statement.

Performance

nstance adds a new score event. The arguments, including options, are the same as in a score. The iwhen time (p2) is measured from the time of this event.

If the duration is zero or negative the new event is of MIDI type, and inherits the release sub-event from the scheduling instruction.

	Note
	Note that the nstance opcode can't accept string p-fields. If you need to pass strings when instantiating an instrument, use the scoreline or scoreline_i opcode.

Examples

Here is an example of the nstance opcode. It uses the file nstance.csd.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in
-odac           -iadc    ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o nstance.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1

; Instrument #1 - oscillator with a high note.
instr 1
  ; Play Instrument #2 at the same time.
  iHandle nstance 2, 0, p3

  ; Play a high note.
  a1 oscils 10000, 880, 1
  out a1
endin

; Instrument #2 - oscillator with a low note.
instr 2
  ; Play a low note.
  a1 oscils 10000, 220, 1
  out a1
endin


</CsInstruments>
<CsScore>

; Table #1, a sine wave.
f 1 0 16384 10 1

; Play Instrument #1 for half a second.
i 1 0 0.5
; Play Instrument #1 for half a second.
i 1 1 0.5
e


</CsScore>
</CsoundSynthesizer>

See Also

schedwhen

See also

event, event_i, schedwhen, schedkwhen, schedkwhennamed, scoreline, scoreline_i

More information on this opcode: http://www.csoundjournal.com/issue15/phrase_loops.html , written by Jim Aikin

Credits