![Kaboom Logo](kaboom.png)

[**Kaboom.js**](https://kaboomjs.com/) is a JavaScript library that helps you make games fast and fun!

Start playing around with it in the [Kaboom Playground](https://kaboomjs.com/play)

## Examples

```js
// initialize context
kaboom()

// load a sprite called "froggy"
loadSprite("froggy", "sprites/froggy.png")

// compose the player game object from multiple components and add it to the game
const froggy = add([
    sprite("bean"),
    pos(80, 40),
    area(),
    body(),
])

// press space to jump
onKeyPress("space", () => {
    // this method is provided by the "body" component above
    froggy.jump()
})
```

Kaboom uses a powerful component system to compose game objects and behaviors.

```js
// add a game obj to the scene from a list of component
const player = add([
    // it renders as a sprite
    sprite("bean"),
    // it has a position
    pos(100, 200),
    // it has a collider
    area(),
    // it is a physical body which will respond to physics
    body(),
    // it has 8 health
    health(8),
    // or give it tags for easier group behaviors
    "player",
    "friendly",
    // plain objects fields are directly assigned to the game obj
    {
        dir: vec2(-1, 0),
        dead: false,
        speed: 240,
    },
])
```

Blocky imperative syntax for describing behaviors

```js
// .onCollide() comes from "area" component
player.onCollide("enemy", () => {
    // .hurt() comes from "health" component
    player.hurt(1)
})

// check fall death
player.onUpdate(() => {
    if (player.pos.y >= height()) {
        destroy(player)
        gameOver()
    }
})

// if 'player' onCollide with any object with tag "enemy", run the callback
player.onCollide("enemy", () => {
    player.hp -= 1
})

// all objects with tag "enemy" will move towards 'player' every frame
onUpdate("enemy", (e) => {
    e.move(player.pos.sub(e.pos).unit().scale(e.speed))
})

// move up 100 pixels per second every frame when "w" key is held down
onKeyDown("w", () => {
    player.move(0, 100)
})
```

## Usage

### NPM

```sh
$ npm install kaboom
```

```js
import kaboom from "kaboom"

kaboom()

add([
    text("oh hi"),
    pos(80, 40),
])
```

also works with CommonJS

```js
const kaboom = require("kaboom")
```

Note that you'll need to use a bundler like `esbuild` or `webpack` to use Kaboom with NPM

### Browser CDN

This exports a global `kaboom` function

```html
<script src="https://unpkg.com/kaboom/dist/kaboom.js"></script>
<script>
kaboom()
</script>
```

or use with es modules

```html
<script type="module">
import kaboom from "https://unpkg.com/kaboom/dist/kaboom.mjs"
kaboom()
</script>
```

works all CDNs that supports NPM packages, e.g. jsdelivr, skypack

## Dev

1. `npm run setup` to setup first time (installing dev packages)
1. `npm run dev` to watch & build lib and the website (the website might take some time to build for the first time)
1. go to http://localhost:3000/play
1. edit demos in `demo/` to test
1. make sure not to break any existing demos

also check out [CONTRIBUTION.md](CONTRIBUTING.md)

## Community

[GitHub Discussions](https://github.com/replit/kaboom/discussions)

[Discord](https://discord.gg/aQ6RuQm3TF)

[Twitter](https://twitter.com/Kaboomjs)

## Games

[**on Itch.io**](https://itch.io/games/tag-kaboomjs)

[**on Replit**](https://replit.com/apps/kaboom)

[**on Newgrounds**](https://www.newgrounds.com/search/conduct/games?tags=kaboomjs)

### Misc

- Thanks to [LaJBel](https://lajbel.repl.co/) for help building the Kaboom community
- Thanks to [abrudz](https://github.com/abrudz) for the amazing [APL386 font](https://abrudz.github.io/APL386/)
- Thanks to [Polyducks](http://polyducks.co.uk/) for the amazing [kitchen sink font](https://polyducks.itch.io/kitchen-sink-textmode-font) font
- Thanks to [0x72](https://0x72.itch.io/) for the amazing [Dungeon Tileset](https://0x72.itch.io/dungeontileset-ii)
- Thanks to [Kenney](https://kenney.nl/) for the amazing [1-Bit Platformer Pack](https://kenney.nl/assets/bit-platformer-pack)
- Find bitmap fonts: [Oldschool PC Font](https://int10h.org/oldschool-pc-fonts)
- Featured on [Console 50](https://console.substack.com/p/console-50)
- Thanks to [Umayr](https://github.com/umayr) for kindly offering the "kaboom" npm package name
- Please buy fireworks on [kaboom.com](http://www.kaboom.com/)
- Documentation for v0.5 [here](https://kaboomlegacy.repl.co/)
- [How to do a KABOOM on a Trampoline](https://www.youtube.com/watch?v=3CemcWdc_Hc)