Unit 12.2A · Term 2

PyGame Setup & Window

PyGame is a Python library for building 2D games. Before you draw anything, you need to install the library, initialize its modules, and create a display window.

Learning Objectives

12.5.1.1 Connect the PyGame library and its modules
12.5.1.2 Create the game window

Lesson Presentation

12.2A-pygame-setup.pdf · Slides for classroom use

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Conceptual Anchor

The TV Screen Analogy

Think of PyGame as setting up a TV: first you plug it in (pygame.init()), then you set the screen size (set_mode()), give it a channel name (set_caption()), and then you're ready to display content.

Rules & Theory

Installing PyGame

# Install via pip
pip install pygame

# Verify installation
python -c "import pygame; print(pygame.ver)"

Core Setup Commands

Command	Purpose
`import pygame`	Import the PyGame library
`pygame.init()`	Initialize ALL PyGame modules (display, sound, fonts, etc.)
`pygame.display.set_mode((w, h))`	Create the game window with width × height
`pygame.display.set_caption("Title")`	Set the window title bar text
`pygame.display.flip()`	Update the full display surface
`pygame.display.update()`	Update portions of the display (or full if no args)
`pygame.quit()`	Shut down all PyGame modules
`sys.exit()`	Exit the Python program completely

Common PyGame Modules

Module	Purpose
`pygame.display`	Window and screen management
`pygame.event`	Event handling (keyboard, mouse, quit)
`pygame.draw`	Drawing shapes on surfaces
`pygame.image`	Loading and saving images
`pygame.font`	Rendering text
`pygame.mixer`	Sound effects and music
`pygame.time`	Timing and frame rate control
`pygame.key`	Keyboard state checking
`pygame.mouse`	Mouse position and button state

Worked Examples

1 Minimal PyGame Window

import pygame
import sys

# 1. Initialize PyGame
pygame.init()

# 2. Create window (800 × 600 pixels)
WIDTH, HEIGHT = 800, 600
screen = pygame.display.set_mode((WIDTH, HEIGHT))

# 3. Set window title
pygame.display.set_caption("My First Game")

# 4. Main loop (keeps window open)
running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    # Fill the screen with a color
    screen.fill((30, 30, 30))  # dark gray

    # Update the display
    pygame.display.flip()

# 5. Clean up
pygame.quit()
sys.exit()

2 Window with Custom Colors

import pygame, sys

pygame.init()

# Define colors
SKY_BLUE = (135, 206, 235)
DARK_GREEN = (34, 139, 34)

screen = pygame.display.set_mode((640, 480))
pygame.display.set_caption("Colored Window")

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    # Sky background
    screen.fill(SKY_BLUE)

    # Green ground (bottom 100px)
    pygame.draw.rect(screen, DARK_GREEN, (0, 380, 640, 100))

    pygame.display.flip()

pygame.quit()
sys.exit()

Common Pitfalls

Forgetting pygame.init()

Without pygame.init(), modules like display, font, and mixer won't work. Always call it before any other PyGame function.

Window Closes Immediately

Without a main loop (while running), the window flashes and closes. The loop keeps the program alive and processing events.

Tasks

Remember

List 5 PyGame modules and their purposes.

Apply

Create a 1024×768 window titled "Space Invaders" with a black background.

Apply

Create a window that changes background color every time it refreshes (hint: use random.randint).

Self-Check Quiz

Q1: What does pygame.init() do?

Initializes all PyGame modules (display, sound, fonts, etc.) so they are ready to use.

Q2: What is the difference between flip() and update()?

flip() updates the entire display surface. update() can update specific areas (or the whole display if no args). flip() is simpler and most commonly used for beginners.

Q3: Why do we need a main loop?

To keep the window open, process events (keyboard, mouse, quit), update game state, and redraw the screen continuously.