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annotate CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/lib/python3.8/turtledemo/fractalcurves.py @ 68:5028fdace37b

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planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 16:23:26 -0400
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jpayne@68 1 #!/usr/bin/env python3
jpayne@68 2 """ turtle-example-suite:
jpayne@68 3
jpayne@68 4 tdemo_fractalCurves.py
jpayne@68 5
jpayne@68 6 This program draws two fractal-curve-designs:
jpayne@68 7 (1) A hilbert curve (in a box)
jpayne@68 8 (2) A combination of Koch-curves.
jpayne@68 9
jpayne@68 10 The CurvesTurtle class and the fractal-curve-
jpayne@68 11 methods are taken from the PythonCard example
jpayne@68 12 scripts for turtle-graphics.
jpayne@68 13 """
jpayne@68 14 from turtle import *
jpayne@68 15 from time import sleep, perf_counter as clock
jpayne@68 16
jpayne@68 17 class CurvesTurtle(Pen):
jpayne@68 18 # example derived from
jpayne@68 19 # Turtle Geometry: The Computer as a Medium for Exploring Mathematics
jpayne@68 20 # by Harold Abelson and Andrea diSessa
jpayne@68 21 # p. 96-98
jpayne@68 22 def hilbert(self, size, level, parity):
jpayne@68 23 if level == 0:
jpayne@68 24 return
jpayne@68 25 # rotate and draw first subcurve with opposite parity to big curve
jpayne@68 26 self.left(parity * 90)
jpayne@68 27 self.hilbert(size, level - 1, -parity)
jpayne@68 28 # interface to and draw second subcurve with same parity as big curve
jpayne@68 29 self.forward(size)
jpayne@68 30 self.right(parity * 90)
jpayne@68 31 self.hilbert(size, level - 1, parity)
jpayne@68 32 # third subcurve
jpayne@68 33 self.forward(size)
jpayne@68 34 self.hilbert(size, level - 1, parity)
jpayne@68 35 # fourth subcurve
jpayne@68 36 self.right(parity * 90)
jpayne@68 37 self.forward(size)
jpayne@68 38 self.hilbert(size, level - 1, -parity)
jpayne@68 39 # a final turn is needed to make the turtle
jpayne@68 40 # end up facing outward from the large square
jpayne@68 41 self.left(parity * 90)
jpayne@68 42
jpayne@68 43 # Visual Modeling with Logo: A Structural Approach to Seeing
jpayne@68 44 # by James Clayson
jpayne@68 45 # Koch curve, after Helge von Koch who introduced this geometric figure in 1904
jpayne@68 46 # p. 146
jpayne@68 47 def fractalgon(self, n, rad, lev, dir):
jpayne@68 48 import math
jpayne@68 49
jpayne@68 50 # if dir = 1 turn outward
jpayne@68 51 # if dir = -1 turn inward
jpayne@68 52 edge = 2 * rad * math.sin(math.pi / n)
jpayne@68 53 self.pu()
jpayne@68 54 self.fd(rad)
jpayne@68 55 self.pd()
jpayne@68 56 self.rt(180 - (90 * (n - 2) / n))
jpayne@68 57 for i in range(n):
jpayne@68 58 self.fractal(edge, lev, dir)
jpayne@68 59 self.rt(360 / n)
jpayne@68 60 self.lt(180 - (90 * (n - 2) / n))
jpayne@68 61 self.pu()
jpayne@68 62 self.bk(rad)
jpayne@68 63 self.pd()
jpayne@68 64
jpayne@68 65 # p. 146
jpayne@68 66 def fractal(self, dist, depth, dir):
jpayne@68 67 if depth < 1:
jpayne@68 68 self.fd(dist)
jpayne@68 69 return
jpayne@68 70 self.fractal(dist / 3, depth - 1, dir)
jpayne@68 71 self.lt(60 * dir)
jpayne@68 72 self.fractal(dist / 3, depth - 1, dir)
jpayne@68 73 self.rt(120 * dir)
jpayne@68 74 self.fractal(dist / 3, depth - 1, dir)
jpayne@68 75 self.lt(60 * dir)
jpayne@68 76 self.fractal(dist / 3, depth - 1, dir)
jpayne@68 77
jpayne@68 78 def main():
jpayne@68 79 ft = CurvesTurtle()
jpayne@68 80
jpayne@68 81 ft.reset()
jpayne@68 82 ft.speed(0)
jpayne@68 83 ft.ht()
jpayne@68 84 ft.getscreen().tracer(1,0)
jpayne@68 85 ft.pu()
jpayne@68 86
jpayne@68 87 size = 6
jpayne@68 88 ft.setpos(-33*size, -32*size)
jpayne@68 89 ft.pd()
jpayne@68 90
jpayne@68 91 ta=clock()
jpayne@68 92 ft.fillcolor("red")
jpayne@68 93 ft.begin_fill()
jpayne@68 94 ft.fd(size)
jpayne@68 95
jpayne@68 96 ft.hilbert(size, 6, 1)
jpayne@68 97
jpayne@68 98 # frame
jpayne@68 99 ft.fd(size)
jpayne@68 100 for i in range(3):
jpayne@68 101 ft.lt(90)
jpayne@68 102 ft.fd(size*(64+i%2))
jpayne@68 103 ft.pu()
jpayne@68 104 for i in range(2):
jpayne@68 105 ft.fd(size)
jpayne@68 106 ft.rt(90)
jpayne@68 107 ft.pd()
jpayne@68 108 for i in range(4):
jpayne@68 109 ft.fd(size*(66+i%2))
jpayne@68 110 ft.rt(90)
jpayne@68 111 ft.end_fill()
jpayne@68 112 tb=clock()
jpayne@68 113 res = "Hilbert: %.2fsec. " % (tb-ta)
jpayne@68 114
jpayne@68 115 sleep(3)
jpayne@68 116
jpayne@68 117 ft.reset()
jpayne@68 118 ft.speed(0)
jpayne@68 119 ft.ht()
jpayne@68 120 ft.getscreen().tracer(1,0)
jpayne@68 121
jpayne@68 122 ta=clock()
jpayne@68 123 ft.color("black", "blue")
jpayne@68 124 ft.begin_fill()
jpayne@68 125 ft.fractalgon(3, 250, 4, 1)
jpayne@68 126 ft.end_fill()
jpayne@68 127 ft.begin_fill()
jpayne@68 128 ft.color("red")
jpayne@68 129 ft.fractalgon(3, 200, 4, -1)
jpayne@68 130 ft.end_fill()
jpayne@68 131 tb=clock()
jpayne@68 132 res += "Koch: %.2fsec." % (tb-ta)
jpayne@68 133 return res
jpayne@68 134
jpayne@68 135 if __name__ == '__main__':
jpayne@68 136 msg = main()
jpayne@68 137 print(msg)
jpayne@68 138 mainloop()