Bye Bye Alien 👾🛩️

A 2D space-shooter built with Phaser 3, TypeScript, Vite and Vitest.

Pick one of four ships on the start screen, then battle waves of
Independence-Day-style alien saucers, dodge asteroid obstacles, grab a
UFO-disguise power-up that maxes out all stats for 10 seconds, and survive
long enough to face the Mothership boss that appears after 30 seconds.

All graphics are procedurally generated pixel art — no external image assets required.

Quick Start

npm install
npm run dev        # starts Vite dev server on http://localhost:3000

Controls

Start screen (ship selection)

Key	Action
← / A	Previous ship
→ / D	Next ship
ENTER / Space	Launch game
Click	Select & launch

In-game

Key	Action
W / ↑	Move up
A / ←	Move left
S / ↓	Move down
D / →	Move right
Space	Fire (also auto-fires)
R	Restart with same ship (after game over)
Q	Return to ship selection (after game over)

Scripts

Command	Description
`npm run dev`	Start dev server with HMR
`npm run build`	Type-check + production build
`npm run preview`	Preview the production build locally
`npm test`	Run unit tests (Vitest)
`npm run test:watch`	Run tests in watch mode

Project Structure

src/
├── main.ts                 # Phaser game bootstrap
├── config/
│   ├── game.ts             # Game-wide constants
│   ├── game.test.ts        # Tests for game constants
│   ├── ships.ts            # ShipStats interface, 4 ships, POWERUP_STATS
│   └── ships.test.ts       # Tests for ship definitions
├── entities/
│   ├── Player.ts           # Player ship class
│   ├── Player.test.ts      # Unit tests (Phaser mocked)
│   ├── Alien.ts            # Alien enemy class
│   ├── Alien.test.ts       # Unit tests (Phaser mocked)
│   ├── Boss.ts             # Mothership boss class
│   └── Boss.test.ts        # Unit tests (Phaser mocked)
├── scenes/
│   ├── StartScene.ts       # Ship-selection start screen
│   └── GameScene.ts        # Main gameplay scene
└── utils/
    ├── textures.ts         # Procedural pixel-art texture generator
    └── textures.test.ts    # Tests for texture generation

Ships

Ship	Style	Speed	HP	Damage	Fire Rate
F-35 Lightning	Balanced all-rounder	300	100	10	5 /s
Valkyrie	Fast interceptor, fragile	420	60	6	9 /s
Titan	Heavy gunship, slow but devastating	180	200	22	2.5 /s
Spectre	Stealth striker, precise long-range	260	80	18	3.5 /s

Power-up

At 20 seconds a UFO-disguise pickup drifts across the screen. Grab it to
temporarily transform into a UFO with maxed-out stats (speed 450, damage 30,
fire rate 10 /s, HP 250) for 10 seconds. A HUD bar shows the remaining time.

Mothership Boss

The Mothership appears at 30 seconds (with a 5-second warning).
It slides in from the right and patrols vertically. It fires aimed
bullets at the player. Below 50 % HP it switches to a 3-way spread
pattern. Defeating it scores 2 000 points and wins the game.

Adding New Ships

Add the key to SHIP_KEYS and a new entry to SHIPS in src/config/ships.ts:

export const SHIP_KEYS = ['f35', 'valkyrie', 'titan', 'spectre', 'raptor'] as const;

export const SHIPS: Record<ShipKey, ShipStats> = {
  // ...existing ships...
  raptor: {
    name: 'F-22 Raptor',
    description: 'Air-superiority fighter. Fast and agile.',
    textureKey: 'raptor',
    bulletTextureKey: 'bullet_raptor',
    speed: 350,
    handling: 1.2,
    damage: 8,
    hp: 80,
    fireRate: 7,
    bulletSpeed: 550,
  },
};

Add generateRaptor(scene) and generateBulletRaptor(scene) functions in
src/utils/textures.ts, and call them from generateTextures().

xnt/bye-bye-alien