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;;;; License: CC0-1.0

#lang racket

(require "46.rkt")
(require "47.rkt")
(require "49.rkt")


(define (transform-painter painter origin corner1 corner2)
  (lambda (frame)
    (let ((m (frame-coord-map frame)))
      (let ((new-origin (m origin)))
        (painter (make-frame
                  new-origin
                  (sub-vect (m corner1) new-origin)
                  (sub-vect (m corner2) new-origin)))))))

(define (flip-vert painter)
  (transform-painter painter
                     (make-vect 0.0 1.0)
                     (make-vect 1.0 1.0)
                     (make-vect 0.0 0.0)))

(define (flip-horiz painter)
  (transform-painter painter
                     (make-vect 1.0 0.0)
                     (make-vect 0.0 0.0)
                     (make-vect 1.0 1.0)))