proton-engine/README.md

Proton is a simple and powerful javascript particle animation engine.

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Proton is a lightweight and powerful Javascript particle animation library. Use it to easily create a variety of cool particle effects.

Check out examples at [http://drawcall.github.io/Proton/](http://drawcall.github.io/Proton/). The **3D version** of the proton engine is here [here](https://github.com/drawcall/three.proton/). An available **react version** is [here](https://github.com/lindelof/particles-bg).

## Features

- **Easy to use** It takes only a dozen lines of code to create a particle animation effect.
- **Multiple effects** Use Proton to create flames, fireworks, bullets, explosions, and more.
- **Any scene** You can use it in frameworks such as `react`, `vue`, `angular`, and `pixi.js`, `Phaser`, etc.
- **Efficient rendering** Its rendering efficiency is very high, you can render tens of thousands of particles in the page.
- **Simulated physics** Proton can simulate various physical properties including gravity and Brownian motion.
- **Several renderers** Proton provides a variety of renderers, of course you can also customize your own renderer
  - `CanvasRenderer` - Proton's canvas renderer
  - `DomRenderer` - Proton's dom renderer, supporting hardware acceleration.
  - `WebGLRenderer` - Proton's webgl renderer.
  - `PixelRenderer` - Proton's pixel renderer, It can implement pixel animation.
  - `EaselRenderer` - Easeljs proton renderer.
  - `EaselRenderer` - Pixi.js proton renderer.
  - `CustomRenderer` - Use a custom renderer that can be applied to any scene.

## Documentation

See detailed documentation please visit [https://projects.jpeer.at/proton/](https://projects.jpeer.at/proton/).
Thank you very much [@matsu7089](https://github.com/matsu7089) for writing a [good tutorial](https://qiita.com/matsu7089/items/dcb7d326e4ec1340eba6).

## Installation

#### Install using npm

> Note: NPM package-name has been changed from `proton-js` to `proton-engine`

```shell
npm install proton-engine --save
```

```javascript
import Proton from "proton-engine";
```

#### OR include in html

```html
<script type="text/javascript" src="js/proton.web.min.js"></script>
```

## Usage

Proton is very simple to use, a dozen lines of code can create a particle animation.

```javascript
import Proton, {
  Emitter,
  Rate,
  Span,
  Radius,
  Life,
  Velocity,
  Color,
  Alpha,
  CanvasRenderer,
} from "proton-engine";

const proton = new Proton();
const emitter = new Emitter();

//set Rate
emitter.rate = new Rate(new Span(10, 20), 0.1);

//add Initialize
emitter.addInitialize(new Radius(1, 12));
emitter.addInitialize(new Life(2, 4));
emitter.addInitialize(new Velocity(3, new Span(0, 360), "polar"));

//add Behaviour
emitter.addBehaviour(new Color("ff0000", "random"));
emitter.addBehaviour(new Alpha(1, 0));

//set emitter position
emitter.p.x = canvas.width / 2;
emitter.p.y = canvas.height / 2;
emitter.emit(5);

//add emitter to the proton
proton.addEmitter(emitter);

// add canvas renderer
const renderer = new CanvasRenderer(canvas);
proton.addRenderer(renderer);
```

## Remarks

- `Proton.Span` (or `Proton.getSpan`) is a very important concept of the Proton engine, it's everywhere. If you understand its usage, you can create almost any desired effect!

- If you want to create wind, rain, or snow, etc, you can use the `emitter.preEmit` method to pre-render the scene.

- Use `Proton.Body` and `Proton.Color` at the same time. I suggest you'd better use the `WebGLRenderer` not `CanvasRenderer`.

- Added `Proton.Cyclone` behavior, you can make vortex effects with Cyclone. Demo please check [here](https://codesandbox.io/s/proton-cyclone-rzweu).

- `proton.fps` In modern browsers, if the FPS exceeds 60 and you want to maintain a stable 60 FPS, you need to set `proton.fps = 60`. You can set this property when the game engine has fixed fps or some browsers have a higher refresh rate.

- Use Euler integration calculation is more accurate (default false) `Proton.USE_CLOCK = false or true;`.

Proton has now been upgraded to the **v4** version. Performance has been greatly improved and api also has some improvements. For more details, please check [here](https://github.com/drawcall/Proton/releases).

## Building

`node` is a dependency, use terminal to install it with:

```javascript
git clone git://github.com/drawcall/Proton.git

...
npm install
npm run build
```

And run example

```javascript
npm start
//vist http://localhost:3001/example/
```

## Changelog

Detailed changes for each release are documented in the [release notes](https://github.com/drawcall/Proton/releases).

## License

Proton is released under the MIT License. http://www.opensource.org/licenses/mit-license