trigseq
trigseq — Accepts a trigger signal as input and outputs a group of values.
Performance
ktrig_in -- input trigger signal
kstart -- start index of looped section
kloop -- end index of looped section
kinitndx -- initial index
![[Note]](images/note.png)
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Note |
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Although kinitndx is listed as k-rate, it is in fact accessed only at init-time. So if you are using a k-rate argument, it must be assigned with init. |
kfn_values -- number of a table containing a sequence of groups of values
kout1 -- output values
kout2, ... (optional) -- more output values
This opcode handles timed-sequences of groups of values stored into a table.
trigseq accepts a trigger signal (ktrig_in) as input and outputs group of values (contained in the kfn_values table) each time ktrig_in assumes a non-zero value. Each time a group of values is triggered, table pointer is advanced of a number of positions corresponding to the number of group-elements, in order to point to the next group of values. The number of elements of groups is determined by the number of koutX arguments.
It is possible to start the sequence from a value different than the first, by assigning to kinitndx an index different than zero (which corresponds to the first value of the table). Normally the sequence is looped, and the start and end of loop can be adjusted by modifying kstart and kloop arguments. User must be sure that values of these arguments (as well as kinitndx) correspond to valid table numbers, otherwise Csound will crash because no range-checking is implemented.
It is possible to disable loop (one-shot mode) by assigning the same value both to kstart and kloop arguments. In this case, the last read element will be the one corresponding to the value of such arguments. Table can be read backward by assigning a negative kloop value.
trigseq is designed to be used together with seqtime or trigger opcodes.
Examples
Here is an example of the trigseq opcode. It uses the file trigseq.csd.
Example 1113. Example of the trigseq opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -odac ;;;realtime audio out ;-iadc ;;;uncomment -iadc if RT audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o trigseq.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 giTimes ftgen 91, 0, 128, -2, 1, 1/2, 1/2, 1/8, 1/8, 1/2,1/2, 1/16, 1/16, 1/16, 1/16, 1/16, 1/16, 1/16, 1/16; times giSeq ftgen 90, 0, 128, -2, 1, 2, .5, 3, .25, 4, .10, 5, .05, 6 ;** sequence amplitude and freq-ratio bins instr 1 icps init p4 iamp init .3 kloop init p5 initndx init p6 kloop2 init p7 initndx2 init p8 kdur init p9 iminTime init p10 imaxTime init p11 kampratio init 1 kfreqratio init 1 ktime_unit expseg iminTime,p3/8,iminTime,p3* 3/4,imaxTime,p3/8,imaxTime ;**ktrig seqtime ktime_unit, kstart, kloop, initndx, kfn_times ;ktrig seqtime 1/ktime_unit, 0, 15, 0, giTimes ktrig metro ktime_unit ;**** trigseq ktrig_in, kstart, kloop, initndx, kfn_values, kout1 [, kout2, kout3, ...., koutN] trigseq ktrig, 0, kloop2,initndx2, giSeq, kampratio, kfreqratio ;atrig = ktrig*10000 schedkwhen ktrig, -1, -1, 3, 0, kdur, kampratio*iamp, kfreqratio*icps ; schedkwhen ktrig, -1, -1, 2, 0, ktrig, kampratio*iamp, kfreqratio*icps endin instr 2 icps init p4 iamp init .2 kloop init p5 initndx init p6 kloop2 init p7 initndx2 init p8 kdur init p9 iminTime init p10 imaxTime init p11 kampratio init 1 kfreqratio init 1 ktime_unit expseg iminTime,p3/8,iminTime,p3* 3/4,imaxTime,p3/8,imaxTime ;**ktrig seqtime ktime_unit, kstart, kloop, initndx, kfn_times ktrig seqtime 1/ktime_unit, 0, 15, 0, giTimes ;ktrig metro ktime_unit ;**** trigseq ktrig_in, kstart, kloop, initndx, kfn_values, kout1 [, kout2, kout3, ...., koutN] trigseq ktrig, 0, kloop2, initndx2, giSeq, kampratio, kfreqratio printk2 ktrig ;atrig = ktrig*10000 ; schedkwhen ktrig, -1, -1, 2, 0, kdur, kampratio*iamp, kfreqratio*icps schedkwhen ktrig, -1, -1, 3, 0, ktrig, kampratio*iamp, kfreqratio*icps endin instr 3 print p3 kenv expseg 1.04, p3,.04 a1 foscili p4*a(kenv-0.04), p5,1,1,kenv*5, 2 outs a1, a1 endin </CsInstruments> <CsScore> f2 0 8192 10 1 ; icps unused unused kloop2 initndx2 kdur iminTime imaxTime s i1 0 6 100 0 0 5 0 .2 3 15 i1 8 6 150 0 0 4 1 .1 4 30 i1 16 6 200 0 0 5 3 .25 8 50 i1 24 6 300 0 0 3 0 .1 1 30 i2 32 6 100 0 0 5 0 .2 1 1 i2 40 6 150 0 0 4 1 .1 .5 .5 i2 48 6 200 0 0 5 3 .25 3 .5 i2 56 6 300 0 0 5 0 .1 1 8 e </CsScore> </CsoundSynthesizer>