The Kyma Language for Sound Design, Version 4.5

RhythmicCellularAutomaton
Scripts Category
This Sound is based on the one-dimensional cellular automata described by Stephen Wolfram in his book
"Theory and Applications of Cellular Automata". The state, an n-place binary number, where n is the
number of Inputs, determines when the Input is turned on and when it is turned off in a given generation.
An integer, rule, is used to determine the next state.
This differs from the CellularAutomaton in that the state is interpreted "horizontally" (rhythmically) rather
than "vertically" (harmonically). Each generation of the automaton is interpreted as a rhythmic pattern,
where a 1 means the Input is turned on, and a 0 means the Input is turned off (for the duration of the
Input).
Input
This Sound is repeated in a pattern determined by the state of the automaton in each generation. When
a value in the state array is 1, the Sound is played, and when a value in the state array is 0, there is a
silence of the same duration as the Sound. This field accepts only one Sound at a time.
Rule
If you look at the rule and the state as 8-bit binary numbers, you can use the rule to compute the next
generation of the state. Number the positions of the digits 0 to 7 counting from right to left. To compute
the next generation of position P of the state: Take the number at position P, P+1 and P-1 (i.e. the
number at position P and its neighbors to the right and to the left). Think of this as a three digit binary
number N that you are going to use as an index into the binary number representing the rule. Look at
position N of the rule. The value at position N of the rule is the value of position P in the next generation
of the state.
For example, if the rule is 2r10101110 and the state is 2r10010101, let’s compute the next generation
state of position 3. The current value at position 3 of the state is ’0’. Looking at position 3 and its two
neighbors as a binary number, we get ’101’ or the number 5. Using this number as an index, look at
position 5 of the rule; it is ’1’. So the value of position three in the next generation is ’1’. When you reach
the rightmost or leftmost digit in the state, make the assumption that there is an infinite number of zeroes
extending both leftwards and rightwards.
Generations
This is the number of generations.
InitialState
Imagine the initial state as an n-bit binary number where n is the size of the collection of Inputs. Each digit
in the binary number corresponds to a Sound in the Input collection; use a 1 to indicate that a Sound is
initiallly on, a 0 to indicate that it is initially off.
GenerationLength
This is the number of bits in each generation.
330