rsc3/doc/examples/ugen/oscillators/v-osc3.help.scm

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Scheme

;; (v-osc3 rate bufpos freq1 freq2 freq3)
;; Three variable wavetable oscillators.
;; A wavetable lookup oscillator which can be swept smoothly across
;; wavetables. All the wavetables must be allocated to the same
;; size. Fractional values of table will interpolate between two
;; adjacent tables. This unit generator contains three oscillators at
;; different frequencies, mixed together.
;; This oscillator requires a buffer to be filled with a wavetable
;; format signal. This preprocesses the Signal into a form which can
;; be used efficiently by the oscillator. The buffer size must be a
;; power of 2.
;; This can be acheived by creating a Buffer object and sending it one
;; of the "b_gen" messages ( sine1, sine2, sine3 ) with the wavetable
;; flag set to true.
;; Note about wavetables: Vosc3 requires the b_gen sine1 wavetable
;; flag to be ON.
;; Allocate and fill tables 0 to 7 with a generated list of harmonic
;; amplitudes.
(with-sc3
(lambda (fd)
(let* ((square
(lambda (a) (* a a)))
(nth
(lambda (i)
(async fd (b-alloc i 1024 1))
(let* ((n (expt (+ i 1) 2))
(a (map (lambda (j)
(square (/ (- n j) n)))
(enum-from-to 0 (- n 1)))))
(async fd (b-gen1 i "sine1" (cons 7 a)))))))
(for-each nth (enum-from-to 0 7)))))
;; oscillator at buffers 0 through 7.
(let ((p (mouse-x kr 0 7 0 0.1))
(f1 (mce2 240 241))
(f2 (mce2 240.27 241.1))
(f3 (mce2 240.43 239.71)))
(audition (out 0 (mul (v-osc3 ar p f1 f2 f3) 0.2))))
;; Reallocate buffers while oscillator is running.
(with-sc3
(lambda (fd)
(for-each
(lambda (i)
(async fd (b-gen1 i "sine1" (cons 7 (replicate-m 16 (random 0 1))))))
(enum-from-to 0 7))))