Poisson-Disc Voronoi Badge by enjalot

index.html

<!DOCTYPE html>
<meta charset="utf-8">
<style>
  body {
    width: 1050px;
    height: 1500px;
    overflow: hidden;
  }

  path {
    fill: white;
    stroke: #de4459;
    stroke-width: 5;
  }
  /*
  path:nth-child(2n+1) {
    
    fill: #de4459;
  }
  */
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var color = "#de4459"
var counter = 0;
var duration = 4000;
  
var bbox = d3.select("body").node().getBoundingClientRect();
var width = 1050,
    height = 1500;

var r = 50;
var sample = poissonDiscSampler(width, height, r);

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height);

var grid;
var points = [[width/2, height/2]];

var voronoi = d3.geom.voronoi();
  
d3.timer(function(elapsed) {
  var mod = -2 
    + 100 * Math.sin(elapsed * Math.PI*2)
    - 5 * Math.cos(elapsed * Math.PI)
  ;
  for (var i = 0; i < 10; ++i) {
    var s = sample(r + mod);
    if (!s) {
      
      renderVoronoi();
      svg.selectAll("circle")
      .remove()
      return true;
    } 

    svg.append("circle")
        .attr("cx", s[0])
        .attr("cy", s[1])
        .attr("r", 0)
      //.transition()
        .attr("r", 2);

  }
  //console.log(elapsed)
});
  
function renderVoronoi() {  
  var noids = voronoi(points);
  /*
  for (var i = 1, n = noids.length; i < n; ++i) {
    draw(noids[i]);
    context.stroke();
  }
  */
  //console.log("noids",noids)
  var cells = svg.selectAll("path.cell").data(noids)
  cells.enter().append("path")
  .attr("d", function(d) { 
    if(!d) return;
    return "M" + d.join("L") + "Z"; 
  }) 
  animate()
}

function animate() {
  d3.selectAll("path")
    .transition()
    .duration(duration).style("fill", "white")
  
  d3.selectAll("path")
  .filter(function(d,i) { return i % (Math.floor(Math.random() * 5)) })
    .transition()
    .delay(duration)
    .duration(duration).style("fill", color)
  /*
    //.each("end", function() {
      //counter += 1;
      counter = Math.floor(Math.random() * 4) + 0
      animate();
    })
    */
  setTimeout(animate, duration*2)
}

// Based on https://www.jasondavies.com/poisson-disc/
function poissonDiscSampler(width, height, radius) {
  var k = 30; // maximum number of samples before rejection
  var radius2 = radius * radius;
  var R = 3 * radius2
  var cellSize = radius * Math.SQRT1_2
  var gridWidth = Math.ceil(width / cellSize)
  var gridHeight = Math.ceil(height / cellSize)
  grid = new Array(gridWidth * gridHeight)
  var queue = []
  var queueSize = 0
  var sampleSize = 0

  return function(newRadius) {
    radius2 = newRadius * newRadius;
  	R = 3 * radius2
  	cellSize = radius * Math.SQRT1_2;
    
    if (!sampleSize) return sample(Math.random()*width,Math.random()*height);

    // Pick a random existing sample and remove it from the queue.
    while (queueSize) {
      var i = Math.random() * queueSize | 0,
          s = queue[i];

      // Make a new candidate between [radius, 2 * radius] from the existing sample.
      for (var j = 0; j < k; ++j) {
        var a = 2 * Math.PI * Math.random(),
            rad = Math.sqrt(Math.random() * R + radius2),
            x = s[0] + rad * Math.cos(a) * Math.random(),
            y = s[1] + rad * Math.sin(a) * Math.random();

        // Reject candidates that are outside the allowed extent,
        // or closer than 2 * radius to any existing sample.
        if (0 <= x && x < width && 0 <= y && y < height && far(x, y)) {
          points.push([x,y])
          return sample(x, y);
        }
      }

      queue[i] = queue[--queueSize];
      queue.length = queueSize;
    }
  };

  function far(x, y) {
    var i = x / cellSize | 0,
        j = y / cellSize | 0,
        i0 = Math.max(i - 2, 0),
        j0 = Math.max(j - 2, 0),
        i1 = Math.min(i + 3, gridWidth),
        j1 = Math.min(j + 3, gridHeight);

    for (j = j0; j < j1; ++j) {
      var o = j * gridWidth;
      for (i = i0; i < i1; ++i) {
        if (s = grid[o + i]) {
          var s,
              dx = s[0] - x,
              dy = s[1] - y;
          if (dx * dx + dy * dy < radius2) return false;
        }
      }
    }

    return true;
  }

  function sample(x, y) {
    var s = [x, y];
    queue.push(s);
    grid[gridWidth * (y / cellSize | 0) + (x / cellSize | 0)] = s;
    ++sampleSize;
    ++queueSize;
    return s;
  }
}

</script>