Snek.rs

A minimal Snake game written in Rust using SDL2.

Gameplay

• Control a snake with WASD keys.
• Eat red food pellets to grow longer and increase your score.
• The game speeds up as your score increases.
• Avoid hitting the walls or your own tail — that's game over.
• Fill the entire board to win!
• Top 5 high scores are persisted to disk and displayed on the game-over screen.
• Press Escape to pause, unpause, or restart after game over.

Keybindings

Key	Action
W	Move up
A	Move left
S	Move down
D	Move right
Escape	Pause / Unpause / Restart

Requirements

• Rust — edition 2021 (stable).
• SDL2 and SDL2_mixer development libraries.

Platform-specific setup

macOS (Apple Silicon):

brew install sdl2 sdl2_mixer

The .cargo/config.toml already points to Homebrew's library path. For Intel Macs, adjust the config or use /usr/local/lib.

Linux (Debian/Ubuntu):

sudo apt-get install libsdl2-dev libsdl2-mixer-dev

Other distributions: install the equivalent sdl2 and sdl2_mixer development packages.

Windows:

Download the SDL2 and SDL2_mixer VC development zips and set the SDL2_LIB_DIR environment variable. See the rust-sdl2 Windows guide for details.

Building & Running

git clone https://github.com/your-username/snek.rs.git
cd snek.rs
cargo run --release

For development:

cargo run

Run the test suite:

cargo test

Architecture

File	Responsibility
src/main.rs	SDL2 init, event loop, delta-time tick accumulator, input & audio
src/context.rs	Game state: snake position/direction, food spawning, collision, score
src/renderer.rs	SDL2 drawing: background, walls, snake, food, pixel-font score HUD
src/audio.rs	SDL2_mixer wrapper — generates WAV sounds programmatically
src/high_scores.rs	Loads/saves top-5 high scores to ~/.snek_highscores

The game renders at up to 60 FPS with game logic ticking at a variable rate (200 ms → 60 ms as the score increases). A delta-time accumulator ensures consistent timing regardless of frame rate. Movement is intentionally discrete (grid-based, cell-by-cell) — no interpolation.

Features

• On-screen pixel-font score display with colour-coded game states
• Progressive difficulty — game speeds up as you eat
• Top-5 high scores persisted in ~/.snek_highscores
• Sound effects (eat chirp, death buzz, win fanfare) — no external audio files needed
• 30 unit tests covering game logic
• Cross-platform CI (Linux, macOS, Windows)

Known Limitations

• Board size and keybindings are not configurable.
• SDL2_mixer must be installed as a system library (not vendored).

License

MIT