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@HansNewbie
Last active July 18, 2021 20:09
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Python Turtle Fractal Plant
# As described in http://en.wikipedia.org/wiki/L-system#Example_7:_Fractal_plant
import turtle
ruleInput = ['F', 'X']
ruleOutput = ["FF", "F-[[X]+X]+F[+FX]-X"]
start = "X"
front = 5
turn = 30
stack = []
dirstack = []
turtle.left(90)
turtle.penup()
turtle.setpos(0, -350)
turtle.pendown()
turtle.shape("turtle")
def generate(iteration):
result = start
temp = ""
for i in range(iteration):
for j in range(len(result)):
for k in range(len(ruleInput)):
if (result[j] == ruleInput[k]):
temp += ruleOutput[k]
break
if (k == len(ruleInput)-1):
temp += result[j]
result = temp
temp = ""
return result
def draw(input):
for x in input:
if (x == 'F'):
turtle.forward(front)
elif (x == '-'):
turtle.left(turn)
elif (x == '+'):
turtle.right(turn)
elif (x == '['):
stack.append(turtle.pos())
dirstack.append(turtle.heading())
elif (x == ']'):
turtle.penup()
post = stack.pop()
direc = dirstack.pop()
turtle.setpos(post)
turtle.setheading(direc)
turtle.pendown()
turtle.hideturtle()
turtle.done()
draw(generate(6))
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