Turtle Programming in Python.pdf

Turtle Programming in Python “Turtle” is a Python feature like a drawing board, which lets us command a turtle to draw all over it! We can use functions like turtle.forward(…) and turtle.right(…) which can move the turtle around. Commonly used turtle methods are : ` Parameter...

Turtle Programming in Python “Turtle” is a Python feature like a drawing board, which lets us command a turtle to draw all over it! We can use functions like turtle.forward(…) and turtle.right(…) which can move the turtle around. Commonly used turtle methods are : ` Parameter Description Turtle() None Creates and returns a new turtle object forward() amount Moves the turtle forward by the specified amount backward() Amount Moves the turtle backward by the specified amount right() angle Turns the turtle clockwise left() angle Turns the turtle counterclockwise penup() None Picks up the turtle’s Pen pendown() None Puts down the turtle’s Pen up() None Picks up the turtle’s Pen down() None Puts down the turtle’s Pen color() Color name Changes the color of the turtle’s pen fillcolor() Color name Changes the color of the turtle will use to fill a polygon heading() None Returns the current heading position() None Returns the current position goto() x, y Move the turtle to position x,y begin_fill() None Remember the starting point for a filled polygon Computer Science Page 1 of 5 Chapter 3  ` Parameter Description end_fill() None Close the polygon and fill with the current fill color dot() None Leave the dot at the current position stamp() None Leaves an impression of a turtle shape at the current location shape() shapename Should be ‘arrow’, ‘classic’, ‘turtle’ or ‘circle’ Plotting using Turtle To make use of the turtle methods and functionalities, we need to import turtle.”turtle” comes packed with the standard Python package and need not be installed externally. The roadmap for executing a turtle program follows 4 steps: 1. Import the turtle module 2. Create a turtle to control. 3. Draw around using the turtle methods. 4. Run turtle.done(). So as stated above, before we can use turtle, we need to import it. We import it as : from turtle import * import turtle After importing the turtle library and making all the turtle functionalities available to us, we need to create a new drawing board(window) and a turtle. Let’s call the window as wn and the turtle as skk. So we code as: wn = turtle.Screen() wn.bgcolor("light green") wn.title("Turtle") skk = turtle.Turtle() Now that we have created the window and the turtle, we need to move the turtle. To move forward 100 pixels in the direction skk is facing, we code: skk.forward(100) We have moved skk 100 pixels forward, Awesome! Now we complete the program with the done() function and We’re done! turtle.done() So, we have created a program that draws a line 100 pixels long. We can draw various shapes and fill different colors using turtle methods. There’s plethora of functions and programs to be coded using the turtle library in python. Let’s learn to draw some of the basic shapes. Shape 1: Square # Python program to draw square # using Turtle Programming import turtle skk = turtle.Turtle() for i in range(4): skk.forward(50) Computer Science Page 2 of 5 Chapter 3  skk.right(90) turtle.done() Shape 2: Star # Python program to draw star # using Turtle Programming import turtle star = turtle.Turtle() star.right(75) star.forward(100) for i in range(4): star.right(144) star.forward(100) turtle.done() Shape 3: Hexagon # Python program to draw hexagon # using Turtle Programming import turtle polygon = turtle.Turtle() num_sides = 6 side_length = 70 angle = 360.0 / num_sides for i in range(num_sides): polygon.forward(side_length) polygon.right(angle) turtle.done() Shape 4: parallelogram import turtle Shape 5 : Circle # Initialize the turtle t = turtle.Turtle()  # Set the turtle's speed t.speed(1) # Draw the parallelogram for i in range(2): t.forward(100) t.left(60) t.forward(50) t.left(120) import turtle # Set up the turtle screen and set the background color to white Computer Science Page 3 of 5 Chapter 3  screen = turtle.Screen() screen.bgcolor("white") # Create a new turtle and set its speed to the fastest possible pen = turtle.Turtle() pen.speed(0) # Set the fill color to red pen.fillcolor("red") pen.begin_fill() # Draw the circle with a radius of 100 pixels pen.circle(100) # End the fill and stop drawing pen.end_fill() pen.hideturtle() # Keep the turtle window open until it is manually closed turtle.done() Some amazing Turtle Programs 1. Spiral Square Outside In and Inside Out import turtle #Inside_Out 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 https://www.youtube.com/watch?v=QPf 2. User Input Pattern # Python program to user input pattern # using Turtle Programming import turtle #Outside_In import turtle import time Computer Science Page 4 of 5 Chapter 3  import random print ("This program draws shapes based on the number you enter in a uniform pattern.") num_str = input("Enter the side number of the shape you want to draw: ") if num_str.isdigit(): squares = int(num_str) angle = 180 - 180*(squares-2)/squares turtle.up x =0 y =0 turtle.setpos(x, y) numshapes = 8 for x in range(numshapes): turtle.color(random.random(), random.random(), random.random()) x += 5 y += 5 turtle.forward(x) turtle.left(y) for i in range(squares): turtle.begin_fill() turtle.down() turtle.forward(40) turtle.left(angle) turtle.forward(40) print (turtle.pos()) turtle.up() turtle.end_fill() time.sleep(11) turtle.bye() 3. Spiral Helix Pattern # Python program to draw # Spiral Helix Pattern # using Turtle Programming 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() Computer Science Page 5 of 5 Chapter 3