vcella — Cellular Automata

*ioutFunc* - number of the table where the state of each cell is stored

*initStateFunc* - number of a table containig the inital states of each cell

*iRuleFunc* - number of a lookup table containing the rules

*ielements* - total number of cells

*irulelen* - total number of rules

*iradius* (optional) - radius of Cellular Automata. At present time CA radius can be 1 or 2 (1 is the default)

*ktrig* - trigger signal. Each time it is non-zero, a new generation of cells is evaluated

*kreinit* - trigger signal. Each time it is non-zero, state of all cells is forced to be that of *initStateFunc*.

*vcella* supports unidimensional cellular automata, where the state of each cell is stored in *ioutFunc*. So *ioutFunc* is a vector containing current state of each cell. This variant vector can be used together with any other vector-based opcode, such as
*adsynt*,
*vmap*,
*vpowv* etc.

*initStateFunc* is an input vector containing the inital value of the row of cells, while *iRuleFunc* is an input vector containing the rules in the form of a lookup table. Notice that *initStateFunc* and *iRuleFunc* can be updated during the performance by means of other vector-based opcodes (for example *vcopy*) in order to force to change rules and status at performance time.

A new generation of cells is evaluated each time *ktrig* contains a non-zero value. Also the status of all cells can be forced to assume the status corresponding to the contents of *initStateFunc* each time *kreinit* contains a non-zero value.

Radius of CA algorithm can be 1 or 2 (optional *iradius* arguement).

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

The following example uses *vcella*

**Example 950. Example of the vcella 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 ; Audio out Audio in -odac -iadc ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o vcella.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; vcella.csd ; by Anthony Kozar ; This file demonstrates some of the new opcodes available in ; Csound 5 that come from Gabriel Maldonado's CsoundAV. sr = 44100 kr = 4410 ksmps = 10 nchnls = 1 ; Cellular automata-driven oscillator bank using vcella and adsynt instr 1 idur = p3 iCArate = p4 ; number of times per second the CA calculates new values ; f-tables for CA parameters iCAinit = p5 ; CA initial states iCArule = p6 ; CA rule values ; The rule is used as follows: ; the states (values) of each cell are summed with their neighboring cells within ; the specied radius (+/- 1 or 2 cells). Each sum is used as an index to read a ; value from the rule table which becomes the new state value for its cell. ; All new states are calculated first, then the new values are all applied ; simultaneously. ielements = ftlen(iCAinit) inumrules = ftlen(iCArule) iradius = 1 ; create some needed tables iCAstate ftgen 0, 0, ielements, -2, 0 ; will hold the current CA states ifreqs ftgen 0, 0, ielements, -2, 0 ; will hold the oscillator frequency for each cell iamps ftgen 0, 0, ielements, -2, 0 ; will hold the amplitude for each cell ; calculate cellular automata state ktrig metro iCArate ; trigger the CA to update iCArate times per second vcella ktrig, 0, iCAstate, iCAinit, iCArule, ielements, inumrules, iradius ; scale CA state for use as amplitudes of the oscillator bank vcopy iamps, iCAstate, ielements vmult iamps, (1/3), ielements ; divide by 3 since state values are 0-3 vport iamps, .01, ielements ; need to smooth the amplitude changes for adsynt ; we could use adsynt2 instead of adsynt, but it does not seem to be working ; i-time loop for calculating frequencies index = 0 inew = 1 iratio = 1.125 ; just major second (creating a whole tone scale) loop1: tableiw inew, index, ifreqs, 0 ; 0 indicates integer indices inew = inew * iratio index = index + 1 if (index < ielements) igoto loop1 ; create sound with additive oscillator bank ifreqbase = 64 iwavefn = 1 iphs = 2 ; random oscillator phases kenv linseg 0.0, 0.5, 1.0, idur - 1.0, 1.0, 0.5, 0.0 aosc adsynt kenv, ifreqbase, iwavefn, ifreqs, iamps, ielements, iphs out aosc * ampdb(68) endin </CsInstruments> <CsScore> f1 0 16384 10 1 ; This example uses a 4-state cellular automata ; Possible state values are 0, 1, 2, and 3 ; CA initial state ; We have 16 cells in our CA, so the initial state table is size 16 f10 0 16 -2 0 1 0 0 1 0 0 2 2 0 0 1 0 0 1 0 ; CA rule ; The maximum sum with radius 1 (3 cells) is 9, so we need 10 values in the rule (0-9) f11 0 16 -2 1 0 3 2 1 0 0 2 1 0 ; Here is our one and only note! i1 0 20 4 10 11 e </CsScore> </CsoundSynthesizer>