;; Fisheye effect - barrel/pincushion distortion
;; Usage: python3 plan.py effects/fisheye.sexp -p strength=0.5 | python3 execute.py - -d . -o output.mp4
;;
;; Parameters:
;;   strength: distortion amount (-1.0 to 1.0, default: 0.5)
;;             positive = barrel (bulge), negative = pincushion

(recipe "fisheye"
  :version "1.0"
  :encoding (:codec "libx264" :crf 20 :preset "medium" :audio-codec "aac" :fps 30)

  (effect fisheye :path "sexp_effects/effects/fisheye.sexp")

  ;; Default parameter (overridden by -p strength=N)
  (def strength 0.5)

  (def video (source :path "monday.webm"))
  (def clip (-> video (segment :start 0 :duration 10)))
  (def result (-> clip (effect fisheye :strength strength)))
  result)