(require (lib "fungraph.ss" "concabs"))
(load "~mc27/labs/quilting/quilting.scm")

;; return a stack of n copies of image
(define stack-copy-of
  (lambda (n image)
      (do ((i 1 (+ i 1))
           (result image (stack result image)))
        ((= i n) result))))

;; return a stack of n copies of images, with the
;; regular image alternating with the inverted one
;; starting with the regular image in the lowest position
(define stack-alternating-copy-of
  (lambda (n image)
    (do ((i 1 (+ i 1))
         (result image (stack (invert result) image)))
      ((= i n) result))))