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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.

            
              html, body {
  margin: 0;
  padding: 0;
  overflow: hidden;
}
#canvas {
  display: block;
  width: 100%;
  height: 100%;
  
  background: black;
}
            
          
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              /*
Recreation of:
https://codepen.io/towc/pen/mJzOWJ
Most of the code is my own, but I used a few things from the original, such as the neon/electric drawing effect using shadows (and replacing the light component of the HSL values), and the ctx.globalCompositeOperation change to make it look nicer.
*/
var ctx = canvas.getContext('2d');

var settings = {
  //these first two aren't currently editable from the control box
  lineLength: 50,
  speed: 1,
  lifeTime: 500,
  maxParticles: 80,
  radius: 1,
  avoidVisited: true,
  clearTrails: function() {ctx.clearRect(0, 0, width, height); visited = [];},
  restart: function() {ctx.clearRect(0, 0, width, height); particles = []; visited = [];}
};
var visited = [];

function onResize() {
  width = canvas.width = window.innerWidth;
  height = canvas.height = window.innerHeight;
}
function rotate(vec, angle) {
  //convert the angle from degrees to radians
  angle = angle * Math.PI / 180;
  return [(vec[0] * Math.cos(angle)) - (vec[1] * Math.sin(angle)), (vec[0] * Math.sin(angle)) + (vec[1] * Math.cos(angle))];
}
//starting directions for particles
var dirVecs = [
  [1, 0],
  rotate([1, 0], 120),
  rotate([1, 0], 240)
];
var particles = [];

function isVisited(x, y) {
  //if the position appears in the visited list
  //using Math.floor should help reduce incorrect results due to rounding errors (hopefully)
  var pos = [Math.floor(x), Math.floor(y)];
  for (var i = 0; i < visited.length; i++) {
    if (visited[i][0] == pos[0] && visited[i][1] == pos[1]) {
      return true;
    }
  }
  return false;
}
function addToVisited(x, y) {
  //add the position to the list if it does not already appear in the list
  if (!isVisited(x, y)) {
    var pos = [Math.floor(x), Math.floor(y)];
    visited.push(pos);
  }
}

function particle() {
  this.x = 0;
  this.y = 0;
  this.age = 0;
  //choose a random starting direction from the possible 3
  this.dir = dirVecs[Math.floor(Math.random() * 3)];
  //color changes based on spawn time
  this.color = 'hsl(' + ((Date.now() / 100.0) % 360.0) + ', 90%, light%)';
}
particle.prototype.updateAndDraw = function() {
  //The movement is all based on a fixed time step, regardless of how quickly it draws
  //This means the hexagons drawn should all be nearly perfect
  this.age += 1;
  //if the age is a multiple of the lineLength (meaning it should make a turn)
  if (this.age % settings.lineLength == 0) {
    //get the two possible directions
    var dir1 = rotate(this.dir, 60);
    var dir2 = rotate(this.dir, -60);
    
    var options = [];
    
    if (settings.avoidVisited) {
      if (!isVisited(this.x + dir1[0] * settings.lineLength, this.y + dir1[1] * settings.lineLength)) {
        //if the first option hasn't been visited before
        options.push(dir1);
      }
      if (!isVisited(this.x + dir2[0] * settings.lineLength, this.y + dir2[1] * settings.lineLength)) {
        //if the second option hasn't been visited before
        options.push(dir2);
      }
      if (options.length == 0) {
        //if both have been visited, both should be made valid choices
        options = [dir1, dir2];
      }
    } else {
      //if the option is off, choose randomly
      options = [dir1, dir2];
    }
    //get a random direction from those possible
    this.dir = options[Math.floor(Math.random() * options.length)];
    
    addToVisited(this.x, this.y);
  }
  ctx.fillStyle = this.color.replace('light', '70');
  ctx.beginPath();
  ctx.arc(width/2.0 + this.x, height/2.0 + this.y, settings.radius, 0, 6.3);
  
  ctx.shadowBlur = settings.radius * 6;
  ctx.shadowColor = this.color.replace('light', '30');
  ctx.fill();
  
  this.x += this.dir[0] * settings.speed;
  this.y += this.dir[1] * settings.speed;
}

function updateAndDraw() {
  ctx.shadowBlur = 0;
  ctx.globalCompositeOperation = 'source-over';
  
  ctx.fillStyle = 'rgba(0, 0, 0, 0.03)';
  ctx.fillRect(0, 0, width, height);
  ctx.globalCompositeOperation = 'lighter';
  
  //go backwards through the particles, allowing them to be removed if neccesary
  for (var i = particles.length - 1; i >= 0; i--) {
    particles[i].updateAndDraw();
    if (particles[i].age > settings.lifeTime) {
      //remove the particle if it is to old
      particles.splice(i, 1);
    }
  }
  if (particles.length < settings.maxParticles) {
    //if more particles can be added
    if (Math.random() > 0.9) {
      particles.push(new particle());
    }
  } else if (particles.length > settings.maxParticles) {
    //if there are two many particles
    particles.splice(0, settings.maxParticles);
  }
  requestAnimationFrame(updateAndDraw);
}
function init() {
  //set the canvas width/height
  onResize();
  
  //update the width/height if the window is resized
  window.onresize = onResize;
  
  //start drawing
  updateAndDraw();
  
  //add controls
  var gui = new dat.GUI();
  //gui.add(settings, 'speed', 0.5, settings.lineLength).step(1);
  gui.add(settings, 'lifeTime', 50, 3000);
  gui.add(settings, 'maxParticles', 1, 200);
  gui.add(settings, 'radius', 0.5, 6);
  gui.add(settings, 'avoidVisited');
  gui.add(settings, 'clearTrails');
  gui.add(settings, 'restart');
}

init();
            
          
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