Lecture 13 — Introduction to Animation⌗

Instructor: Laksh Budhrani

Objectives⌗

Understand that an animation is made of repeated frames.
Use a variable to change an object’s position over time.

How Animation Works⌗

An animation redraws the scene many times per second.

Draw the object at its current position.
Change the position stored in a variable.
Draw the object again at its new position.

Repeating these steps makes the object appear to move.

Frame-by-frame animation logic

Setup — Create `animation.py`⌗

Create a Python file named animation.py and copy the following code into it. This file provides the animation framework that we will use in class.

import turtle

def run_sketch(draw_function, width=600, height=400,
               fps=30, bgcolor="skyblue"):
    screen = turtle.Screen()
    screen.setup(width, height)
    screen.bgcolor(bgcolor)
    screen.tracer(0)

    p = turtle.Turtle()
    p.hideturtle()
    p.speed(0)
    p.pensize(2)

    def frame_tick():
        p.clear()
        p.penup()
        p.goto(0, 0)
        p.setheading(0)

        draw_function(p)

        screen.update()
        screen.ontimer(frame_tick, int(1000 / fps))

    screen.ontimer(frame_tick, 100)
    screen.mainloop()

Guided Activity — Moving Car⌗

We will write the car animation code together in class.

Create a new Python file named animation_car.py.

Car Animation Video⌗

Starter Template⌗

Copy this template into animation_car.py. We will fill in the code together.

from animation import run_sketch

def draw(p):
    pass
    # Write the car drawing code here


    # Update the car's position here


run_sketch(draw, bgcolor="lightblue")

Independent Activity — Moving Ship⌗

Create a new Python file named animation_ship.py.

Ship Animation Video⌗

Your Task⌗

Create a simple ship and animate it moving from left to right.

Your animation should:

Draw a simple ship with a hull and a sail.
Use a variable to store the ship’s horizontal position.
Update the position each frame so the ship moves to the right.

Use the car animation as a guide, but write the ship code yourself.

Submission Instructions⌗

Submit your work in Google Classroom by:

Creating a Google Doc.
Pasting your code into the document.
Adding a screenshot of the animation window.
Turning in the Google Doc to the assigned activity.

Lecture 13 - Introduction to Animation