The Kyma Language for Sound Design, Version 4.5

snd duration: (1.0 / snd frequency hz).
In this case, the duration of the input will be exactly one cycle long.
If a transforming statement tries to perform arithmetic on a parameter name that is not present in the input
or one of its inputs, Kyma will return an error message, informing you that a message was sent to
nil. For example, suppose the current Sound lacks the parameter CmRatio. When Kyma encounters the
transforming statement
snd frequency: snd cmRatio * 0.5.
you will get an error for trying to multiply nil by 0.5. To protect against using nil in a calculation, test
the value and only perform the calculation if the value is not nil. For example, the following transforming
statement is protected against calculating with nil:
snd cmRatio isNil ifFalse: [snd frequency: snd cmRatio * 0.5].
The effect is to set the frequency to cmRatio * 0.5 in Sounds where CmRatio is present and to skip over
Sounds where that parameter is absent.
Time-varying Transformations
Skipping Levels
Two values, time and totalDuration, are available in ParameterTransformers. The value of time is
the start time in microseconds of the Sound being transformed. The value of totalDuration is the duration
in microseconds of the ParameterTransformer’s input. You can use time and totalDuration to
construct transformations that depend on the start time of a input within the structure.
Suppose the input of a ParameterTransformer is a Repetition of an Oscillator.
The result of the transformation
snd frequency: snd frequency * (1 + (time / totalDuration)).
is a sequence of Sounds with higher and higher frequencies.
Transformations are made to the initial values of a Sound’s parameters; thus, any variation in the transformation
over time is manifested only at the start time of each Sound, not over the course of a Sound and
not on a sample-by-sample basis.
In the default case, a transformation is applied to each level of the input’s structure. If you want to stop
the transformation from continuing beyond a certain level of the sound structure, use
snd doNotTransformSubSounds.
To continue applying transformations to inputs, use
snd transformSubSounds.
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