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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <h1>Canvas Particle System</h1>
    <canvas id="canvas" class="canvas"></canvas>
            
          
!
            
              html {
    font: 16px/1.5 'Work Sans', sans-serif;
    color: #444;
}

body {
    background-color: #214;
    padding: 0;
    margin: 0;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
}

h1 {
    font-size: 5em;
    text-align: center;
    font-weight: 200;
    color: #dce;
  opacity: .1;
}

.canvas {
    position: absolute;
    top: 0;
    left: 0;
  pointer-events: none;
}
            
          
!
            
              'use strict';

var mouse, originx, originy, int, cvs;

/* Safari doesn't support EventTarget :( */
var EventTarget = EventTarget || false;
if (EventTarget) {
  EventTarget.prototype.evt = function (event, callback) {
    return this.addEventListener(event, callback);
  }
}
else {
  window.evt = function (event, callback) {
    return this.addEventListener(event, callback);
  };
  document.evt = function (event, callback) {
    return this.addEventListener(event, callback);
  };
  Element.prototype.evt = function (event, callback) {
    return this.addEventListener(event, callback);
  };
}


function $(elemId) {
    return document.getElementById(elemId);
}

function init() {
    cvs = $("canvas");

    resizeCanvas(cvs);

    window.evt('resize', resizeCanvas, false);
    window.evt("mousemove", function (e) {
        mouse = getMousePos(cvs, e);
        originx = mouse.x;
        originy = mouse.y;
      
    });
    // window.evt("touchmove", function (e) {
    //     originx = e.originalEvent.touches[0].pageX;
    //     originy = e.originalEvent.touches[0].pageY;
    // });

    var network = new Field(0, 0, 50);
    var emit = new Emitter(0, 0, 50);
    
    animateCanvas(cvs, function () {
        network.animate();
        emit.animate();
    });
}

class Point {
    constructor(x, y, canvas, dia) {
        this.canvas = canvas || cvs;
        this.x = x || 0;
        this.y = y || 0;
        this.vx = 0;
        this.vy = 0;
        this.speed = Math.random() * .5 + .2;
        this.angle = Math.random() * 360;
        this.diaSet = dia || 2 + Math.random() * 10;
        this.dia = this.diaSet;
        this.age = 0;
        let hue = Math.floor(Math.random()*360);
        this.fill = 'hsl('+hue+', 95%, 70%)';
        this.line = Math.random() > .5 ? true : false;
    }

    emit(life) {
        let s = this.speed * 2;
        this.angle += Math.random() * 10 - 5;
        this.x += s * Math.cos(this.angle * Math.PI / 180);
        this.y += s * Math.sin(this.angle * Math.PI / 180);
        this.age += 1 / life;
        this.boundary();
    }

    boundary() {
        if (this.x < 0) {
            this.x = this.canvas.width;
        }
        if (this.x > this.canvas.width) {
            this.x = 0;
        }
        if (this.y < 0) {
            this.y = this.canvas.height;
        }
        if (this.y > this.canvas.height) {
            this.y = 0;
        }
    }

    field(life) {
        let s = this.speed;
        this.angle += Math.random() * 10 - 5;
        this.x += s * Math.cos(this.angle * Math.PI / 180);
        this.y += s * Math.sin(this.angle * Math.PI / 180);
        this.age += 1 / life;
        this.boundary();
    }

    shrink(life) {
        this.dia = (1 - this.age) * this.diaSet;
    }

    draw() {
        let ctx = this.canvas.getContext('2d'),
            x = this.x,
            y = this.y,
            dia = this.dia,
            age = this.age;

        ctx.beginPath();
        ctx.fillStyle = this.fill;
        ctx.strokeStyle = this.fill;
        ctx.lineWidth = 2;
        ctx.arc(x, y, dia, 0, 2 * Math.PI);
        ctx.closePath();
        
        this.line !== true ? ctx.fill() : ctx.stroke();
    }
}

class Particle {

    setPosition(x, y) {
        this.x = x;
        this.y = y;
    }

    getPosition(x, y) {
        return {
            x: this.x,
            y: this.y
        };
    }

    spawn(x, y, amount, dia) {

        var arr = [];
        dia = dia || false;

        amount = amount || 1;

        if (amount > 1) {
            for (let i = 0; i < amount; i++) {
                if (dia) {
                    arr.push(new Point(x, y, cvs, dia));
                }
                else {
                    arr.push(new Point(x, y, cvs));
                }
                
            }
        } else {
            arr = new Point(x, y, cvs, dia);
        }

        return arr;
    }
}

// Particle Emitter
class Emitter extends Particle {
    constructor(x, y, life, mouse, dia) {
        super();

        if (mouse === undefined) {
            this.mouse = true;
        } else {
            this.mouse = mouse;
        }

        this.particles = [];
        this.x = x || 0;
        this.y = y || 0;
        this.life = life || 20;
        this.canvas = cvs;
        this.dia = dia || false;
    }

    animate() {
        let particles = this.particles;
        if (this.mouse) {
            this.setPosition(originx, originy);
        }

        let mul = 1;

        for (let i = 0; i < mul; i++) {
            particles.push(this.spawn(this.x, this.y, 1));
        }
        
        if (particles.length > this.life * mul) {
            for (let i = 0; i < mul; i++) {
                particles.shift();
            }
        }

        this.render(this.canvas);
    }
    
    render() {
        let life = this.life;
        let ctx = this.canvas.getContext('2d');
        let particles = this.particles;

        for (let i = 0; i < particles.length; i++) {
            const p = particles[i];
            p.draw();
            p.emit(this.life);
            p.shrink();
        }
    }
}

// Particle Field
class Field extends Particle {
    constructor(x, y, life) {
        super();
        this.particles = [];
        this.canvas = cvs;
        this.x = x || 0;
        this.y = y || 0;
        this.life = life;

        for (let i = 0; i < this.life; i++) {
            let x = Math.random() * cvs.width,
                y = Math.random() * cvs.height;

            this.particles.push(this.spawn(x, y, 1));
        }
    }

    animate() {
        this.render(canvas);
    }

    render(canvas) {
        let ctx = this.canvas.getContext('2d');
        let particles = this.particles;

        for (let i = 0; i < particles.length; i++) {
            const p = particles[i];
            p.draw();
            p.field(this.life);
        }
    }
}

function getMousePos(cvs, evt) {
    var rect = cvs.getBoundingClientRect();
    return {
        x: evt.clientX - rect.left,
        y: evt.clientY - rect.top
    };
}

//
function animateCanvas(canvas, callback) {

    let ctx = canvas.getContext('2d');
    ctx.clearRect(0, 0, canvas.width, canvas.height);
    callback();

    requestAnimationFrame(animateCanvas.bind(null, canvas, callback));
}

//Update canvas size to fill window
function resizeCanvas(canvas) {
    canvas.width = window.innerWidth;
    canvas.height = window.innerHeight;
    originx = canvas.width / 2;
    originy = canvas.height / 2;
}

init();
            
          
!
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