[python]代码库
from turtle import *
from random import *
from math import *
def tree(n, l):
pd() # 下笔
# 阴影效果
t = cos(radians(heading() + 45)) / 8 + 0.25
pencolor(t, t, t)
pensize(n / 3)
forward(l) # 画树枝
if n > 0:
b = random() * 15 + 10 # 右分支偏转角度
c = random() * 15 + 10 # 左分支偏转角度
d = l * (random() * 0.25 + 0.7) # 下一个分支的长度
# 右转一定角度,画右分支
right(b)
tree(n - 1, d)
# 左转一定角度,画左分支
left(b + c)
tree(n - 1, d)
# 转回来
right(c)
else:
# 画叶子
right(90)
n = cos(radians(heading() - 45)) / 4 + 0.5
pencolor(n, n * 0.8, n * 0.8)
circle(3)
left(90)
# 添加0.3倍的飘落叶子
if (random() > 0.7):
pu()
# 飘落
t = heading()
an = -40 + random() * 40
setheading(an)
dis = int(800 * random() * 0.5 + 400 * random() * 0.3 + 200 * random() * 0.2)
forward(dis)
setheading(t)
# 画叶子
pd()
right(90)
n = cos(radians(heading() - 45)) / 4 + 0.5
pencolor(n * 0.5 + 0.5, 0.4 + n * 0.4, 0.4 + n * 0.4)
circle(2)
left(90)
pu()
# 返回
t = heading()
setheading(an)
backward(dis)
setheading(t)
pu()
backward(l) # 退回
bgcolor(0.5, 0.5, 0.5) # 背景色
ht() # 隐藏turtle
speed(0) # 速度 1-10渐进,0 最快
tracer(0, 0)
pu() # 抬笔
backward(100)
left(90) # 左转90度
pu() # 抬笔
backward(300) # 后退300
tree(10, 100) # 递归10层
done()
[代码运行效果截图]