python-turtle drawing

• • Meet Turtle

• Turtle is a renderer

• Built based on the underlying graphics programming structure (API), mainly used for scene construction and 3D object rendering (3D games, virtual scenes, etc.)

• Turtle is a form program

• Turtle is a very popular function library for drawing images in the Python language. Imagine a little turtle starts at the origin (0,0) of a coordinate system with the horizontal axis as x and the vertical axis as y. It follows a set of function instructions. Control, moves in this plane coordinate system, thereby drawing graphics on the path it crawls

• Graphical user interface (GUI) is a computer operation user interface displayed graphically. Turtle is a very standard GUI application.

• • related functions

• • Canvas settings

• The canvas is the drawing area expanded by the turtle. Its size and initial position can be set. There are two commonly used canvas methods.

• turtle.screensize(800,600,"red"): Set the canvas size (width, height, background color), default 800*600, white

• tuetle.setup(500,500,0,0): Not only can you set the width and height, but you can also set the x and y coordinates when the program is running.

• • Brush movement commands

• turtle.forward(distance): Move distance pixel length to the current brush direction, default to right

• turtle.backward(distance): Move distance pixel length in the opposite direction of the current brush

• turtle.right(degree): move degree° clockwise

• turtle.left(degree): move counterclockwise degree°

• turtle.pendown(): Draw graphics when moving, the default is also drawing

• turtle.goto(x,y): Move the brush to the position where the coordinates are x, y

• turtle.penup(): Lift the pen and move it without drawing graphics. It is used to draw in another place.

• tuetle.circle(): Draw a circle with a positive (negative) radius, which means the center of the circle is to the left (right) of the brush to draw a circle.

• setx(): Move the current x-axis to the specified position

• sety(): Move the current y-axis to the specified position

• turtle.speed(): Controls the speed of brush drawing (1-10)

• sentheading(angle): Set the current heading angle

• home():设置当前画笔位置为原点，朝向东

• dot():绘制一个指定直径和颜色的圆点

• • 画笔控制命令

• turtle.pensize():设置线条粗细

• turtle.fillcolor(colorstring):绘制图形的填充颜色

• turtle.color(color1,color2):同时设置pencolor=color1，fillcolor=color2，要在画之前，第一个是画笔颜色，第二个是填充颜色

• turtle.begin_fill():准备开始填充

• turtle.end_fill():填充完成

• turtle.filling():返回当前是否在填充状态

• turtle.hideturtle():隐藏画笔的turtle形状

• turtle.showturtle():显示画笔的turtle形状

• • 全局控制命令

• turtle.clear():清空当前turtle窗口，但是turtle的位置和状态不变

• turtle.reset():清空窗口，重置turtle状态为起始状态

• turtlr.undo():撤销上一个turtle动作

• turtle.isvisivle():返回当前turtle是否可见

• stamp():复制当前图形

• turtle.write(s [,font=("font-name",font_size,"font_type")]):写文本，s为文本内容，font是字体的参数，分别为字体名称，大小和类型；font为可选项，font参数也是可选项

• • 其他命令

• turtle.mainloop():启动事件循环 -调用Tkinter的mainloop函数。

• turtle.done():表示所有工作已经做完了(一般在所有代码之后，放在最后一行)

• turtle.delay(delay=None):设置或返回以毫秒为单位的绘图延迟。

• turtle.begin_poly():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.end_poly():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.get_poly():返回最后记录的多边形

• • 案例

• • 爱的魔力

代码

import turtle as t
import random
t.speed(0)
for i in range(50):
    t.circle(80)
    t.right(100)
t.done()

• • 奥运五环

代码

import turtle as t
import random
# 圆环
# 奥运五环
t.pensize(9)
# 蓝环
t.color('blue')
t.circle(75)
t.penup()
t.forward(150)
t.pendown()
# 黑环
t.color('black')
t.circle(75)
t.penup()
t.forward(150)
t.pendown()
# 红环
t.color('red')
t.circle(75)
t.penup()
t.goto(220, -100)
t.pendown()
# 黄环
t.color('yellow')
t.circle(75)
t.penup()
t.goto(100, -100)
t.pendown()
# 绿环
t.color('green')
t.circle(75)
# 字体
t.color('black')
t.penup()
t.goto(50, 200)
t.pendown()
t.write('北京 2022', font=('YouYuan', 32))
t.done()

• • 美队盾牌

代码

import turtle as t
import random
#美国盾牌
t.penup()
t.goto(0,-200)
t.pendown()
t.color('red')
t.begin_fill()
t.circle(200)
t.end_fill()

t.penup()
t.goto(0, -150)
t.pendown()
t.color('white')
t.begin_fill()
t.circle(150)
t.end_fill()

t.penup()
t.goto(0, -100)
t.pendown()
t.color('red')
t.begin_fill()
t.circle(100)
t.end_fill()

t.penup()
t.goto(0, -60)
t.pendown()
t.color('blue')
t.begin_fill()
t.circle(60)
t.end_fill()

t.penup()
t.goto(-50, 18)
t.pendown()
t.color('white')
t.begin_fill()
for i in range(5):
    t.forward(105)
    t.right(144)
t.end_fill()
t.done()

• • 彩球飘飘

代码

import turtle as t
import random
# 彩旗飘飘
t.colormode(255)
for i in range(20):
    # 设置RGB值，随机生成
    red = random.randint(0, 255)
    green = random.randint(0, 255)
    blue = random.randint(0, 255)
    # 设置气球随机位置，随机生成x，y坐标
    x = random.randint(-400, 400)
    y = random.randint(-100, 300)
    # 移动到指定的位置
    t.penup()
    t.goto(x, y)
    t.pendown()
    # 设置填充颜色
    t.color(red, green, blue)
    # 填充和画圆
    t.begin_fill()
    t.circle(30)
    t.end_fill()
    # 画线
    t.right(90)
    t.forward(30)
    t.left(90)
t.done()

• • 夜空繁星

代码

import turtle as t
import random

if __name__ == '__main__':
    # 繁星漫天
    # 夜空
    t.speed(0)
    t.screensize(800, 600, 'black')
    t.colormode(255)
    t.pensize(250)
    for i in range(10):
        t.goto(-500, 400 - i * 100)
        t.color(i * 20, i * 20, i * 20)
        t.forward(1000)
    # 星星
    for j in range(25):
        x = random.randint(-400, 400)
        y = random.randint(0, 400)
        size = random.randint(5, 20)
        t.color('yellow')
        t.penup()
        t.goto(x, y)
        t.pendown()
        t.pensize(3)
        t.begin_fill()
        for i in range(4):
            t.forward(size)
            t.left(30)
            t.forward(size)
            t.right(120)
        t.end_fill()
    t.done()