titansoftime/three-nebula

WebGL based particle system engine for three.js

    three-nebula

    WebGL based 3D particle system engine for three

    

---

CHANGELOG

Three Nebula is a WebGL based 3D particle engine that has been designed to work alongside three.js. Check out the website, examples, the quickstart sandbox and API reference documentation for more.

Features

• Perfect compatibility with three@0.122.0
• The ability to instantiate three-nebula particle systems from JSON objects
• The ability to create particle systems from sprites as well as 3D meshes
• Many kinds of particle behaviours and initializers

Installation

npm

npm i --save three-nebula

script

<script type='text/javascript' src='node_modules/three-nebula/build/three-nebula.js'></script>

Usage

Module

import System, {
  Emitter,
  Rate,
  Span,
  Position,
  Mass,
  Radius,
  Life,
  Velocity,
  PointZone,
  Vector3D,
  Alpha,
  Scale,
  Color,
} from 'three-nebula';
import * as THREE from 'three';

const system = new System();
const emitter = new Emitter();
const renderer = new SpriteRenderer(threeScene, THREE);

// Set emitter rate (particles per second) as well as the particle initializers and behaviours
emitter
  .setRate(new Rate(new Span(4, 16), new Span(0.01)))
  .setInitializers([
    new Position(new PointZone(0, 0)),
    new Mass(1),
    new Radius(6, 12),
    new Life(3),
    new RadialVelocity(45, new Vector3D(0, 1, 0), 180),
  ])
  .setBehaviours([
    new Alpha(1, 0),
    new Scale(0.1, 1.3),
    new Color(new THREE.Color(), new THREE.Color()),
  ]);

// add the emitter and a renderer to your particle system
system
  .addEmitter(emitter)
  .addRenderer(renderer)
  .emit({ onStart, onUpdate, onEnd });

You can also instantiate your system from a JSON object

import System from 'three-nebula';

const json = {
  preParticles: 500,
  integrationType: 'euler',
  emitters: [
    {
      rate: {
        particlesMin: 5,
        particlesMax: 7,
        perSecondMin: 0.01,
        perSecondMax: 0.02,
      },
      position: {
        x: 70,
        y: 0,
      },
      initializers: [
        {
          type: 'Mass',
          properties: {
            min: 1,
            max: 1,
          },
        },
        {
          type: 'Life',
          properties: {
            min: 2,
            max: 2,
          },
        },
        {
          type: 'BodySprite',
          properties: {
            texture: './img/dot.png',
          },
        },
        {
          type: 'Radius',
          properties: {
            width: 80,
            height: 80,
          },
        },
      ],
      behaviours: [
        {
          type: 'Alpha',
          properties: {
            alphaA: 1,
            alphaB: 0,
          },
        },
        {
          type: 'Color',
          properties: {
            colorA: '#4F1500',
            colorB: '#0029FF',
          },
        },
        {
          type: 'Scale',
          properties: {
            scaleA: 1,
            scaleB: 0.5,
          },
        },
        {
          type: 'Force',
          properties: {
            fx: 0,
            fy: 0,
            fz: -20,
          },
        },
      ],
    },
    {
      rate: {
        particlesMin: 5,
        particlesMax: 7,
        perSecondMin: 0.01,
        perSecondMax: 0.02,
      },
      position: {
        x: -70,
        y: 0,
      },
      initializers: [
        {
          type: 'Mass',
          properties: {
            min: 1,
            max: 1,
          },
        },
        {
          type: 'Life',
          properties: {
            min: 2,
            max: 2,
          },
        },
        {
          type: 'BodySprite',
          properties: {
            texture: './img/dot.png',
          },
        },
        {
          type: 'Radius',
          properties: {
            width: 80,
            height: 80,
          },
        },
      ],
      behaviours: [
        {
          type: 'Alpha',
          properties: {
            alphaA: 1,
            alphaB: 0,
          },
        },
        {
          type: 'Color',
          properties: {
            colorA: '#004CFE',
            colorB: '#6600FF',
          },
        },
        {
          type: 'Scale',
          properties: {
            scaleA: 1,
            scaleB: 0.5,
          },
        },
        {
          type: 'Force',
          properties: {
            fx: 0,
            fy: 0,
            fz: -20,
          },
        },
      ],
    },
  ],
};

new System.fromJSONAsync(json, THREE).then(system => {
  console.log(system);
});

Script Tag

If you are adding three-nebula to your project in the script tag, the only difference to the above example is how you access the classes you need. You can do that like so

const { System, Emitter, Rate, Span } = window.Nebula;
const system = new System();

Development

Sandbox

The sandbox located in ./sandbox contains a kind of plain JavaScript bootstrapping framework for testing and experimenting with library changes. The experiments in here are not permanent and will get updated/added/removed from time to time.

Because of the visual and graphical nature of the library it is sometimes very helpful to have simple barebones examples that allow you to dig into the root cause of an issue or try new things out.

The sandbox can easily be run via

npm run sandbox

This will serve the sandbox at http://localhost:5000 and you can checkout the various experiments in the browser. It will also auto rebuild the library code and push the rebuilt bundle to the sandbox so all you need to do in order to see your changes is to refresh the browser.

License

MIT