大部分python安装环境下都包含turtle这个绘图模块,它可以让你使用海龟图像(当然可以设置为箭头)来绘制图形,现在,我们来用它来做些小东西。
一、基本的几何图形
画一个正方形:
import turtle
bob = turtle.Turtle()
for i in range(1,5):
bob.fd(100)
bob.lt(90)
turtle.mainloop()
画一个圆:
import turtle
import math
def circle(t,r,a):
#传入接口arc,在arc中完成大部分计算
arc(t,r,a)
def arc(t,r,a):
#计算边的长度,同时设定边的个数
length = 2 * math.pi * r * abs(a) / 360
n = int(length / 4) + 3
step_length = length / n
step_angle = a / n
polygon(t, step_length, n)
def polygon(t, length, n):
#画出图形
for i in range(n):
t.fd(length)
t.lt(360/n)
bob = turtle.Turtle()
radius = 50
angle = 360
circle(bob, radius, angle)
turtle.mainloop()
画一条阿基米德螺线:
import turtle
def draw_spiral(t, n, length=3, a=0.1, b=0.0002):
#Draws an Archimedian spiral starting at the origin
theta = 0.0
for i in range(n):
t.fd(length)
dtheta = 1 / (a + b * theta)
t.lt(dtheta)
theta += dtheta
#create the world and bob
bob = turtle.Turtle()
draw_spiral(bob, n=1000)
turtle.mainloop()

二、通过基本图形组合画一些现实中简单的物体
花朵:
import turtle
def draw_diamond(turt):
for i in range(1,3):
turt.forward(100)
turt.right(45)
turt.forward(100)
turt.right(135)
def draw_art():
window = turtle.Screen() #视窗
window.bgcolor("black") #背景颜色
brad = turtle.Turtle() #创建一个“乌龟”对象
brad.shape("turtle") #设定画笔图像是乌龟
brad.color("red") #设定画笔颜色是红色
brad.speed("fast") #画画速度是快
for i in range(1, 37): #调用diamond函数36次,即画36个花瓣
draw_diamond(brad)
brad.right(10)
brad.right(90) #画出枝干
brad.forward(1000)
window.exitonclick()
draw_art()
上面实现的这个花朵是不是有点儿捞???
那我们试一试把前面画圆的代码来实现三个好看的花朵:
import math
import turtle
def polyline(t, n, length, angle):
#Draws n line segments
for i in range(n):
t.fd(length)
t.lt(angle)
def arc(t, r, angle):
#Draws an arc with given radius and angle
arc_length = 2 * math.pi * r * abs(angle) / 360
n = int(arc_length / 4) + 3
step_length = arc_length / n
step_angle = float(angle) / n
t.lt(step_angle/2)
polyline(t, n, step_length, step_angle)
t.rt(step_angle/2)
def petal(t, r, angle):
#Draws a petal using two arcs.
for i in range(2):
arc(t, r, angle)
t.lt(180 - angle)
def flower(t, n, r, angle):
#Draws a flower with n petals
for i in range(n):
petal(t, r, angle)
t.lt(360.0/n)
def move(t, length):
#Move turtle(t) forwoard (length) units without leaving a trail
t.pu()
t.fd(length)
t.pd()
bob = turtle.Turtle()
#draw a sequence of three flowers
move(bob, -100)
flower(bob, 7, 60.0, 60.0)
move(bob, 100)
flower(bob, 10, 40.0, 80.0)
move(bob, 100)
flower(bob, 20, 140.0, 20.0)
bob.hideturtle()
turtle.mainloop()
当然,我们通过那个简单的花朵是知道其实turtle是可以设置颜色的,那第一种花朵有颜色但是形状不好看,第二种形状好看但是颜色单调,那么让我们集合二者的优点,做一些“花里胡哨”的东西。
“花里胡哨”橡皮球:
import turtle
t = turtle.Pen()
turtle.bgcolor("black")
#sides = eval(str(input("输入要绘制的边的数目,请输入2-6Dev数字! ")))
sides = 6
colors = ["red","yellow","green","blue","orange","purple"]
for x in range(360):
t.pencolor(colors[x%sides]) #随机颜色
t.speed("fast")
t.forward(x*3/sides+x) #六边形长度依次增加
t.left(360/sides+1) #转动角度依次变化
t.width(x*sides/180)
t.left(91)
print ("结束")
三、将上面的简单现实物体拆分组合为复杂的现实物体
一个简单的时钟程序(通过前面的代码,颜色可以自己定义反正你的时钟你做主~ ~,同时本程序用到了python的time模块,不懂得朋友可自行度娘~ ~),ok,代码如下:
import turtle
from datetime import *
# 抬起画笔,向前运动一段距离放下
def Skip(step):
turtle.penup()
turtle.forward(step)
turtle.pendown()
def mkHand(name, length):
# 注册Turtle形状,建立表针Turtle
turtle.reset()
Skip(-length * 0.1)
# 开始记录多边形的顶点。当前的乌龟位置是多边形的第一个顶点。
turtle.begin_poly()
turtle.forward(length * 1.1)
# 停止记录多边形的顶点。当前的乌龟位置是多边形的最后一个顶点。将与第一个顶点相连。
turtle.end_poly()
# 返回最后记录的多边形。
handForm = turtle.get_poly()
turtle.register_shape(name, handForm)
def Init():
global secHand, minHand, hurHand, printer
# 重置Turtle指向北
turtle.mode("logo")
# 建立三个表针Turtle并初始化
mkHand("secHand", 135)
mkHand("minHand", 125)
mkHand("hurHand", 90)
secHand = turtle.Turtle()
secHand.shape("secHand")
minHand = turtle.Turtle()
minHand.shape("minHand")
hurHand = turtle.Turtle()
hurHand.shape("hurHand")
for hand in secHand, minHand, hurHand:
hand.shapesize(1, 1, 3)
hand.speed(0)
# 建立输出文字Turtle
printer = turtle.Turtle()
# 隐藏画笔的turtle形状
printer.hideturtle()
printer.penup()
def SetupClock(radius):
# 建立表的外框
turtle.reset()
turtle.pensize(7)
for i in range(60):
Skip(radius)
if i % 5 == 0:
turtle.forward(20)
Skip(-radius - 20)
Skip(radius + 20)
if i == 0:
turtle.write(int(12), align="center", font=("Courier", 14, "bold"))
elif i == 30:
Skip(25)
turtle.write(int(i/5), align="center", font=("Courier", 14, "bold"))
Skip(-25)
elif (i == 25 or i == 35):
Skip(20)
turtle.write(int(i/5), align="center", font=("Courier", 14, "bold"))
Skip(-20)
else:
turtle.write(int(i/5), align="center", font=("Courier", 14, "bold"))
Skip(-radius - 20)
else:
turtle.dot(5)
Skip(-radius)
turtle.right(6)
def Week(t):
week = ["星期一", "星期二", "星期三",
"星期四", "星期五", "星期六", "星期日"]
return week[t.weekday()]
def Date(t):
y = t.year
m = t.month
d = t.day
return "%s年%d月%d日" % (y, m, d)
def Tick():
# 绘制表针的动态显示
t = datetime.today()
second = t.second + t.microsecond * 0.000001
minute = t.minute + second / 60.0
hour = t.hour + minute / 60.0
secHand.setheading(6 * second)
minHand.setheading(6 * minute)
hurHand.setheading(30 * hour)
turtle.tracer(False)
printer.forward(65)
printer.write(Week(t), align="center",
font=("Courier", 14, "bold"))
printer.back(130)
printer.write(Date(t), align="center",
font=("Courier", 14, "bold"))
printer.home()
turtle.tracer(True)
# 100ms后继续调用tick
turtle.ontimer(Tick, 100)
def main():
# 打开/关闭龟动画,并为更新图纸设置延迟。
turtle.tracer(False)
Init()
SetupClock(160)
turtle.tracer(True)
Tick()
turtle.mainloop()
if __name__ == "__main__":
main()
四、结语
OK~ ~ ~,这就是我对自己休息turtle库的一些新的与整理。希望大家通过这几段代码能够很好的理解python的turtle库。