prepare-square-pattern-batch.scm

;; This Gimp script creates a 64x64 version of the given flag from the Mutant standard icon set:
;;     https://mutant.tech/use/#mastodon
;;
;; Save in your ~/.gimp-2.8/scripts directory.
;; You can call it as follows:
;;     gimp -i -b '(batch-prepare-square-pattern "pattern.png")' -b '(gimp-quit 0)'
;; It will create the file "pattern-square.png" with the final, 64x64 square version.
(define (batch-prepare-square-pattern pattern-path)
  (let* ((pattern-image (car (gimp-file-load RUN-NONINTERACTIVE pattern-path pattern-path)))
         (pattern-layer (car (gimp-image-get-active-layer pattern-image))))
    (plug-in-autocrop RUN-NONINTERACTIVE pattern-image pattern-layer)
    (gimp-image-crop pattern-image 80 80 8 8)
    (gimp-image-scale pattern-image 64 64)
    (let* ((pattern-basename (car (strbreakup pattern-path ".")))
           (final-filename-png (string-append pattern-basename "-square.png")))
      (gimp-file-save RUN-NONINTERACTIVE pattern-image pattern-layer final-filename-png final-filename-png))))