;; Invert effect - inverts all colors
;; Uses vectorized invert-img primitive for fast processing
;; amount param: 0 = no invert, 1 = full invert (threshold at 0.5)

(require-primitives "color_ops")

(define-effect invert
  :params ((amount :type float :default 1 :range [0 1]))
  (if (> amount 0.5) (invert-img frame) frame))