Alien Invasion Game (Python)

Practice project built with Python and Pygame to recreate the classic Alien Invasion arcade shooter from Python Crash Course. The repo also includes a handful of small Python language exercises in basic/ for reference.

Repository Layout

• alien_invasion/ – main game package (entry point, sprites, settings, art assets)
• basic/ – stand-alone scripts used for Python fundamentals practice
• README.md – this guide

Prerequisites

• Python 3.10+ (the code uses modern typing-friendly idioms but no 3.11-specific features)
• pip (comes with Python) and optionally python -m venv for isolated environments

macOS note: The project has been tested on macOS using the system Python launcher (python3). On Linux/Windows replace python3 with python as appropriate.

Quick Start

# from the project root
python3 -m venv .venv
source .venv/bin/activate        # Windows: .venv\\Scripts\\activate
pip install --upgrade pip
pip install pygame

python alien_invasion/alien_invasion.py

When the game window appears, steer with the arrow keys, press Space to fire bullets, and press Q to quit.

If you prefer a requirements file you can capture the environment once it works:

pip freeze > requirements.txt

Anyone cloning the project can then run pip install -r requirements.txt to reproduce your exact dependency set.

Game Configuration

Runtime options live in alien_invasion/settings.py. Update the attributes below, then restart the game to apply the changes:

Setting	Default	Effect
screen_width	1200	Window width in pixels
screen_height	800	Window height in pixels
bg_color	(230, 230, 230)	Background RGB tuple
ship_speed	1.5	Player ship horizontal speed
bullet_speed	2.0	Vertical bullet speed
bullet_width	3	Bullet thickness in pixels
bullet_height	15	Bullet height in pixels
bullet_color	(60, 60, 60)	Bullet RGB color
bullet_allowed	3	Simultaneous bullets on screen

For alternate setups, commit the tweaked settings.py alongside notes on the hardware (monitor resolution, refresh rate) to help others replicate the same feel. Keep images/ship.bmp in place or update ship.py to load your custom sprite.

Development Tips

• Use python -m pygame.examples.aliens to confirm Pygame installed correctly if the game fails to open a window.
• The main loop caps the frame rate at 60 FPS via pygame.time.Clock; adjust there if you experiment with higher refresh rates.
• To package or distribute, consider freezing dependencies (pip freeze) and shipping the images/ assets with the script.

Next Steps

• Expand gameplay by adding aliens (see later chapters in the book for guidance).
• Add automated tests around settings or sprite helpers with pytest if you want regression coverage.
• Document any new modules here so others know how to run them.