@smoud/tiny/examples/jsm/particles/Firework.js

Fast and tiny JavaScript library for HTML5 game and playable ads creation.

var normTime, speed;

export default class FireworkParticle extends Tiny.Particle {
    constructor(emitter) {
        super(emitter);
    }

    update(time, delta) {
        normTime = time / this.maxlifespan;

        this.scale.set(Math.tan(normTime * normTime));

        this.alpha = Math.min(Math.tan(normTime), 1);

        speed = normTime * normTime * normTime * 10;

        this.x += this.xspeed * speed * delta * normTime;
        this.y += this.yspeed * speed * delta + normTime * 10 * delta;
    }

    onEmit() {
        var randAgle = Math.random() * Math.PI * 2;

        var rand_speed = Math.random() * 3;

        this.maxlifespan = this.lifespan;

        this.xspeed = Math.sin(randAgle) * rand_speed * 0.05;
        this.yspeed = Math.cos(randAgle) * rand_speed * 0.05;
    }

    draw(context, resolution) {
        context.beginPath();
        context.arc(0, 0, 20 * resolution, 0, 2 * Math.PI, false);
        context.fill();
    }
}