;; (peak-follower in decay)

;; Track peak signal amplitude.  outputs the peak amplitude of the
;; signal received at the input.  If level is below maximum, the level
;; decreases by the factor given in decay.

;; in    - input signal.
;; decay - decay factor.

;; internally, the absolute value of the signal is used, to prevent
;; underreporting the peak value if there is a negative DC offset. To
;; obtain the minimum and maximum values of the signal as is, use the
;; running-min and running-max UGens.


;; No decay

(let* ((s (mul (dust ar 20) (line kr 0 1 4 do-nothing)))
       (f (mul-add (peak-follower s 1.0) 1500 200)))
  (audition (out 0 (mul (sin-osc ar f 0) 0.2))))

;; A little decay

(let* ((s (mul (dust ar 20) (line kr 0 1 4 do-nothing)))
       (f (mul-add (peak-follower s 0.999) 1500 200)))
  (audition (out 0 (mul (sin-osc ar f 0) 0.2))))

;; Mouse x controls decay

(let* ((x (mouse-x kr 0.99 1.0001 1 0.1))
       (s (mul (dust ar 20) (line kr 0 1 4 do-nothing)))
       (f (mul-add (peak-follower s (u:min x 1.0)) 1500 200)))
  (audition (out 0 (mul (sin-osc ar f 0) 0.2))))

;; Follow a sine lfo

(let* ((x (mouse-x kr 0.99 1.0001 1 0.1))
       (s (sin-osc kr 0.2 0))
       (f (mul-add (peak-follower s (u:min x 1.0)) 200 500)))
  (audition (out 0 (mul (sin-osc ar f 0) 0.2))))