Turtle Programming in Python

Turtle is a Python module that provides a virtual drawing board where one can control a cursor (called a turtle) to draw shapes and patterns on the screen using simple commands.

1. Control Movement: Move the turtle to exact positions and rotate it in any direction.
2. Interactive: The drawing can respond to mouse clicks or keyboard input.
3. Set Speed: One can make the turtle draw faster or slower to see the drawing step by step.
4. Change Pen Style: You can change the color and thickness of the pen and fill shapes with colors.
5. Draw Shapes and Stamps: You can draw shapes or leave a turtle-shaped stamp on the screen.

Plotting Using Turtle

To use Turtle in Python, simply import turtle (no installation needed). A basic Turtle program follows four steps:

1. Import the turtle module: import Turtle in Python in the following ways.

import turtle

or

from turtle import *

2. Create a turtle to control: After importing the turtle library, we create a drawing window and a turtle. Here, 'wn' is the window and 'skk' is the turtle.

wn = turtle.Screen()
wn.bgcolor("light green")
wn.title("Turtle")
skk = turtle.Turtle()

3. Draw around using the turtle methods: Now that the window and turtle are ready, we can move the turtle. For example, to move skk forward by 100 pixels.

skk.forward(100)

4. Run turtle.done(): This draws a line 100 pixels long in the direction 'skk' is facing. To finish the program, call.

turtle.done()

Examples

Below are some examples of Turtle programs demonstrating different shapes and patterns.

Shape 1: Square

In this program, we show how to draw a square using Turtle in Python.

import turtle 
skk = turtle.Turtle()

for i in range(4):
    skk.forward(50)
    skk.right(90)
    
turtle.done()

Output

Explanation:

• skk = turtle.Turtle(): Create a turtle named skk.
• skk.forward(50): Move forward 50 units.
• skk.right(90): Turn 90° clockwise.
• turtle.done(): Keep the window open.

Shape 2: Star

In this program, we show how to draw a star using Turtle in Python.

import turtle
star = turtle.Turtle()

star.right(75)
star.forward(100)

for i in range(4):
    star.right(144)
    star.forward(100)
    
turtle.done()

Output

Some Turtle Programs

1. Spiral Square Outside In and Inside Out

In this program, we draw spiral squares that grow outward and inward to create a visually interesting pattern.

import turtle 
wn = turtle.Screen()
wn.bgcolor("light green")
skk = turtle.Turtle()
skk.color("blue")

def sqrfunc(size):
    for i in range(4):
        skk.fd(size)
        skk.left(90)
        size = size + 5

sqrfunc(6)
sqrfunc(26)
sqrfunc(46)
sqrfunc(66)
sqrfunc(86)
sqrfunc(106)
sqrfunc(126)
sqrfunc(146)

Output

Explanation:

• wn = turtle.Screen(): Creates a drawing window (canvas).
• wn.bgcolor("light green"): Sets the background color of the window to light green.
• skk = turtle.Turtle(): Creates a Turtle object named skk to draw shapes.
• skk.color("blue"): Sets the pen color of the turtle to blue.
• skk.fd(size): Moves the turtle forward by size units.
• skk.left(90): Turns the turtle 90 degrees left after each side.
• size = size + 5: Increases the side length slightly for each iteration (creates a growing effect).
• sqrfunc(6), sqrfunc(26), … Calls the function multiple times with increasing initial sizes to draw multiple squares in sequence.

2. Spiral Helix Pattern 

In this program, we create a spiral helix pattern by drawing circles with increasing and decreasing radii.

import turtle
loadWindow = turtle.Screen()
turtle.speed(2)

for i in range(100):
    turtle.circle(5*i)
    turtle.circle(-5*i)
    turtle.left(i)

turtle.exitonclick()

Output

Explanation:

• loadWindow = turtle.Screen(): Creates the drawing window.
• turtle.speed(2): Sets the turtle’s drawing speed.
• turtle.circle(5*i): Draws a circle with increasing radius.
• turtle.circle(-5*i): Draws a circle in the opposite direction.
• turtle.left(i): Rotates the turtle to form a spiral effect.
• turtle.exitonclick(): Keeps the window open until a mouse click.

Common Turtle Methods

Below are some common Turtle methods used to move the turtle, draw shapes and control colors.

Related Articles:

• turtle.write() function
• turtle.home() function