blob: 30ea9d37503fb2b73e8532fe84f3c2731d1565c6 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
#lang sketching
(require racket/list)
(define (setup)
(size 200 200)
(frame-rate 20)
(loop))
(define Line cons)
(define ->0 car)
(define ->1 cdr)
(define Point cons)
(define ->x car)
(define ->y cdr)
(define Rgb list)
(define ->r first)
(define ->g second)
(define ->b third)
(define (draw/line my-line)
(let [ (p1 (->0 my-line)) (p2 (->1 my-line)) ]
(line (->x p1) (->y p1) (->x p2) (->y p2))))
;; Parameters
(define iterations 50)
(define spoke-ratio 0.6)
(define total-spokes 8)
(define max-spoke-depth 10)
(define (start-length) (/ (min width height) 5))
(define (start-point) (Point (/ width 2) (/ height 2)))
(define min-curvature 0.5)
(define max-curvature 2.0)
;; State
(define current-iteration 0)
(define spoke-depth -2)
(define curvature 0.4)
(define (get-color n)
(Rgb
(* 255 (+ n 0.9))
180 255))
(define (tentacle point len angle spokes)
(let [
(p2 (Point (+ (->x point) (* len (cos angle)))
(+ (->y point) (* len (sin angle)))))
(color (get-color (/ spokes total-spokes) ))
]
(stroke (->r color) (->g color) (->b color))
(draw/line (Line point p2))
(if (> spokes 1)
(begin
(tentacle p2 (* len spoke-ratio) (+ angle curvature) (- spokes 1))
(tentacle p2 (* len spoke-ratio) (- angle curvature) (- spokes 1)))
'())))
(define (draw)
(color-mode 'hsb 255)
(background 0)
(stroke-weight 2)
(stroke 255 255 255)
(for-each
(lambda (angle)
(tentacle (start-point) (start-length) (* angle (/ 2π total-spokes)) spoke-depth))
(range 0 total-spokes))
(if (= current-iteration iterations)
(no-loop)
(begin
(set! current-iteration (+ current-iteration 1))
(set! spoke-depth (min (+ spoke-depth 1) max-spoke-depth))
(if (> current-iteration 8)
(set! curvature (min (max (+ curvature 0.02) min-curvature) max-curvature))
'()))))
|
