Description

Generate control signal consisiting of linear segments delimited by two or more specified points. The entire envelope can be looped at time-variant rate. Each segment coordinate can also be varied at k-rate.

Syntax

ksig loopsegp  kphase, kvalue0, kdur0, kvalue1 \
      [, kdur1, ... , kdurN-1, kvalueN]

Performance

ksig - output signal

kphase - point of the sequence read, expressed as a fraction of a cycle (0 to 1)

kvalue0 ...kvalueN - values of points

kdur0 ...kdurN-1 - duration of points expessed in fraction of a cycle

loopsegp opcode is similar to loopseg; the only difference is that, instead of frequency, a time-variant phase is required. If you use phasor to get the phase value, you will have a behaviour identical to loopseg, but interesting results can be achieved when using phases having non-linear motions, making loopsegp more powerful and general than loopseg.

Examples

Here is an example of the loopsegp opcode. It uses the file loopsegp.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 loopsegp.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>
sr=44100
ksmps=1
nchnls=2

; By Mark Van Peteghem 2008

   instr 1
iphase  = p4

kenv      linen 1, 0.1, p3, 0.1
kph_amp   phasor 2, 0
kamp      loopsegp kph_amp, 60, 1, 30, 1, 60
kamp    = ampdb(kamp)*kenv

kph_freq  phasor 2, iphase
klow_freq line 200, p3, 100
kfreq     loopsegp kph_freq, 400, 1, klow_freq, 1, 400

asig      vco2 kamp, kfreq, 2, 0.5

         outs asig, asig

   endin

</CsInstruments>
<CsScore>
i1 0 3 0
i1 + . 0.50
</CsScore>
</CsoundSynthesizer>

Credits

Written by Gabriel Maldonado.

New in Csound 5. (Previously available only on CsoundAV)