1 12687dd9 2023-08-04 jrmu ;; The first three lines of this file were inserted by DrScheme. They record metadata
 2 12687dd9 2023-08-04 jrmu ;; about the language level of this file in a form that our tools can easily process.
 3 12687dd9 2023-08-04 jrmu #reader(lib "htdp-intermediate-reader.ss" "lang")((modname 18.1.8) (read-case-sensitive #t) (teachpacks ((lib "draw.ss" "teachpack" "htdp"))) (htdp-settings #(#t constructor repeating-decimal #f #t none #f ((lib "draw.ss" "teachpack" "htdp")))))
 4 12687dd9 2023-08-04 jrmu (define MRPOLY (list (make-posn 20 30)
 5 12687dd9 2023-08-04 jrmu                      (make-posn 30 40)
 6 12687dd9 2023-08-04 jrmu                      (make-posn 50 90)
 7 12687dd9 2023-08-04 jrmu                      (make-posn 100 40)
 8 12687dd9 2023-08-04 jrmu                      (make-posn 150 80)
 9 12687dd9 2023-08-04 jrmu                      (make-posn 240 120)
10 12687dd9 2023-08-04 jrmu                      (make-posn 40 10)))
11 12687dd9 2023-08-04 jrmu 
12 12687dd9 2023-08-04 jrmu (define (modified-draw-polygon a-poly)
13 12687dd9 2023-08-04 jrmu   (local ((define (draw-polygon a-poly)
14 12687dd9 2023-08-04 jrmu             (cond
15 12687dd9 2023-08-04 jrmu               [(empty? (rest a-poly)) true]
16 12687dd9 2023-08-04 jrmu               [else (connect-dots (cons (last a-poly) a-poly))]))
17 12687dd9 2023-08-04 jrmu           
18 12687dd9 2023-08-04 jrmu           (define (connect-dots a-poly)
19 12687dd9 2023-08-04 jrmu             (cond
20 12687dd9 2023-08-04 jrmu               [(empty? (rest a-poly)) true]
21 12687dd9 2023-08-04 jrmu               [else (and
22 12687dd9 2023-08-04 jrmu                      (draw-solid-line (first a-poly)
23 12687dd9 2023-08-04 jrmu                                       (second a-poly)
24 12687dd9 2023-08-04 jrmu                                       'black)
25 12687dd9 2023-08-04 jrmu                      (connect-dots (rest a-poly)))]))
26 12687dd9 2023-08-04 jrmu           
27 12687dd9 2023-08-04 jrmu           (define (last a-poly)
28 12687dd9 2023-08-04 jrmu             (cond
29 12687dd9 2023-08-04 jrmu               [(empty? (rest a-poly)) (first a-poly)]
30 12687dd9 2023-08-04 jrmu               [else (last (rest a-poly))]))
31 12687dd9 2023-08-04 jrmu           (define (add-at-end a-poly first-posn)
32 12687dd9 2023-08-04 jrmu             (cond
33 12687dd9 2023-08-04 jrmu               [(empty? (rest a-poly)) (first a-poly)]
34 12687dd9 2023-08-04 jrmu               [else (cons (add-at-end a-poly first-posn) (cons first-posn empty))]))
35 12687dd9 2023-08-04 jrmu           (define (modified-draw-polygon a-poly)
36 12687dd9 2023-08-04 jrmu             (cond
37 12687dd9 2023-08-04 jrmu               [(empty? (rest a-poly)) true]
38 12687dd9 2023-08-04 jrmu               [else (connect-dots (add-at-end a-poly (first a-poly)))])))
39 12687dd9 2023-08-04 jrmu     (modified-draw-polygon a-poly)))
40 12687dd9 2023-08-04 jrmu 
41 12687dd9 2023-08-04 jrmu (start 500 500)
42 12687dd9 2023-08-04 jrmu (modified-draw-polygon MRPOLY)