Description

This opcode outputs a trigger signal that informs when any one of its k-rate arguments has changed, or a value in an array. Useful with valuator widgets or MIDI controllers.

Syntax

ktrig changed2 kvar1 [, kvar2,..., kvarN]

ktrig changed2 karr[]

ktrig changed2 aarr[]

Performance

ktrig - Outputs a value of 1 when any of the k-rate signals has changed, or any value in the array, otherwise outputs 0.

kvar1 [, kvar2,..., kvarN] - k-rate variables to watch for changes.

xarray - any array type.

Unlike the opcode changed this opcode will never report the first cycle as a change.

Examples

Here are two examples of the changed2 opcode. They use the files changed2.csd and changed2a.csd.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac     ;;;RT audio out
;-iadc    ;;;uncomment -iadc if RT audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o changed.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2

instr 1

ksig  oscil 2, 0.5, 1
kint  = int(ksig)
ktrig changed2 kint
      printk 0.2, kint
      printk2 ktrig

endin

</CsInstruments>
<CsScore>
f 1 0 1024 10 1
i 1 0 20

e
</CsScore>
</CsoundSynthesizer>

Its output should include lines like:

 i   1 time     0.00267:     0.00000
 i1     0.00000
 i1     1.00000
 i1     0.00000
 i   1 time     0.20267:     1.00000
 i   1 time     0.40267:     1.00000
 i1     1.00000
 i1     0.00000
 i   1 time     0.60267:     1.00000
 i   1 time     0.80267:     1.00000
 i1     1.00000
 i1     0.00000
 i   1 time     1.00000:     0.00000
 i1     1.00000
 i1     0.00000
 i   1 time     1.20267:    -1.00000
 i   1 time     1.40267:    -1.00000
 i1     1.00000
 i1     0.00000
 i   1 time     1.60267:    -1.00000
 i   1 time     1.80000:    -1.00000
 i1     1.00000
 i1     0.00000
 i   1 time     2.00000:    -0.00000
 i1     1.00000
 i1     0.00000
 .........
      

<CsoundSynthesizer>

<CsOptions>
-n
</CsOptions>
<CsInstruments>
gkArray[][] init   2,3
gkArray     fillarray  1,2,3,7,6,5

instr 1
k1 changed2 gkArray
if k1==1 then
    printks "An element in the array changed", 0
endif
endin

instr 2; change value of channel 'step1'
    gkArray[1][0] = 3
endin

</CsInstruments>
<CsScore>
i1 0 100
i2 4 .1
</CsScore>

</CsoundSynthesizer>

See also

Sensing and Control: Tempo and Sequencing

Credits

Written by John ffitch.

Example written by Andrés Cabrera.

New in Csound 6.7