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HTML

              
                
              
            
!

CSS

              
                head, body{
  width:100%;
  height:100%;
  overflow: hidden;
  top:0;
  left:0;
  margin:0;
  padding:0;
}
              
            
!

JS

              
                //ported from http://devmag.org.za/2009/05/03/poisson-disk-sampling/

var Poisson = function( exports )
{

    var width, height, grid;

    function distribute( count, radius, w, h )
    {
        width = w;
        height = h;

        var cellSize = exports.cellSize = radius / Math.sqrt( 2 );
        exports.grid = grid = buildGrid( Math.ceil( w / cellSize), Math.ceil( h / cellSize) );
        count = Math.min( count, Math.floor( w / cellSize) * Math.floor( h / cellSize) )

        var processList = [];
        var firstPoint = new Point( w *.5, h *.5);
        processList.push(firstPoint);

        setGridPoint( imageToGrid(firstPoint, cellSize), firstPoint );

        var result = [];

        var total = count;
        while( result.length < count )
        {

            var added = false;
            var attempt = 10;

            while( !added ){

                var rid = ~~( Math.random() * processList.length );
                var point = processList[ rid ];
                var newPoint = generateRandomPointAround( point, radius );

                //check that the point is in the image region
                //and no points exists in the point's neighbourhood
                if( inRectangle(newPoint)
                &&  !inNeighbourhood( grid, newPoint, radius, cellSize ) )
                {
                    processList.push(newPoint);
                    result.push(newPoint);
                    setGridPoint( imageToGrid( newPoint, cellSize ),  newPoint );
                    added = true;
                }
                if(attempt--<=0)break;
            }
            if(total--<=0)break;

        }
        return result;
    }

    function buildGrid( w, h )
    {
        var g = [];
        for( var i = 0; i < w; i++ )
        {
            var tmp = [];
            for( var j = 0; j < h; j++ )
            {
                tmp.push( null );
            }
            g.push( tmp );
        }
        return g;
    }

    function setGridPoint( gridPoint, value )
    {

        if( grid[ gridPoint.x ][ gridPoint.y ] != null )return;
        grid[ gridPoint.x ][ gridPoint.y ] = value;
    }

    function inRectangle( point )
    {
        return point.x > 0 && point.x < width && point.y > 0 && point.y < height;
    }

    function imageToGrid( point, cellSize)
    {
        var gridX = ~~( point.x / cellSize );
        var gridY = ~~( point.y / cellSize );
        return new Point(gridX, gridY);
    }

    function generateRandomPointAround( point, mindist )
    {
        var r1 = Math.random();
        var r2 = Math.random();
        var radius = mindist * ( r1 + 1);
        var angle = 2 * Math.PI * r2;
        var newX = point.x + radius * Math.cos(angle);
        var newY = point.y + radius * Math.sin(angle);
        return new Point(newX, newY);
    }

    function inNeighbourhood( grid, point, mindist, cellSize)
    {
        var gridPoint = imageToGrid( point, cellSize );

        var cellsAroundPoint = squareAroundPoint( grid, gridPoint.x, gridPoint.y, 4 );

        var valid = false;
        cellsAroundPoint.forEach( function( cell ){
            if( cell == null )return;

            var min_dist = mindist;

            //using a noise (or any non-uniform) function
            //var min_dist = mindist + simplex.simplex2( point.x * .01, point.y * .01 ) * mindist;

            if( distance( cell, point ) < min_dist ){

                valid = true;
            }
        });
        return valid;
    }

    function squareAroundPoint( grid, x, y, offset )
    {
        var off = Math.round( offset / 2 );
        var minX = Math.max( 0, Math.min( grid.length, x - off ) );
        var maxX = Math.max( 0, Math.min( grid.length, x + off ) );
        var minY = Math.max( 0, Math.min( grid[0].length, y - off ) );
        var maxY = Math.max( 0, Math.min( grid[0].length, y + off ) );
        var tmp = [];
        for( var i = minX; i < maxX; i++ )
        {
            for( var j = minY; j < maxY; j++ )
            {
                if( grid[ i ][ j ] != null )tmp.push( grid[ i ][ j ] );
            }
        }
        return tmp;
    }

    exports.distribute = distribute;
    return exports;
}( {} );


var Point = function()
{
    function Point(x,y,z)
    {
        this.x = x || 0;
        this.y = y || 0;
        this.z = z || 0;
    }

    var _p = Point.prototype;
    _p.constructor = Point;

    return Point;

}();
function distance(a,b)
{
    var dx = a.x - b.x;
    var dy = a.y - b.y;
    var dz = a.z - b.z;
    return Math.sqrt( dx*dx + dy*dy + dz*dz );
}

///////////////////////////////////////////////////////////

var canvas = document.createElement( 'canvas' );
document.body.appendChild( canvas );
var w = canvas.width = window.innerWidth;
var h = canvas.height = window.innerHeight;
var ctx = canvas.getContext("2d");

//raf: https://github.com/cagosta/requestAnimationFrame/blob/master/app/requestAnimationFrame.js
(function(global) {(function() {if (global.requestAnimationFrame) {return;} if (global.webkitRequestAnimationFrame) {global.requestAnimationFrame = global[ 'webkitRequestAnimationFrame' ]; global.cancelAnimationFrame = global[ 'webkitCancelAnimationFrame' ] || global[ 'webkitCancelRequestAnimationFrame' ];} var lastTime = 0; global.requestAnimationFrame = function(callback) {var currTime = new Date().getTime(); var timeToCall = Math.max(0, 16 - (currTime - lastTime)); var id = global.setTimeout(function() {callback(currTime + timeToCall);}, timeToCall); lastTime = currTime + timeToCall; return id;}; global.cancelAnimationFrame = function(id) {clearTimeout(id);};})(); if (typeof define === 'function') {define(function() {return global.requestAnimationFrame;});}})(window);

///////////////////////////////////////////////////////////


var radius = 15;
var distribution;
var length;
function init(){

  w = canvas.width = window.innerWidth;
  h = canvas.height = window.innerHeight;
  distribution = Poisson.distribute( 1000, radius, w, h );
  length = distribution.length;

}

function update() {
  requestAnimationFrame(update);
  if (distribution == null)return;
  for( var i = 0; i < 10; i++ )
  {
    if (distribution.length == 0)return;
    var id = distribution.length;
    p = distribution.shift();
    ctx.globalAlpha = 1.25 - ( id / length );
    ctx.beginPath();
    ctx.arc(p.x, p.y, ( id / length ) * radius / 2, 0, Math.PI * 2);
    ctx.fill();
  }

}
window.onload = init;
window.onresize = init;
window.onmousedown = init;
window.ontouchstart = init;
update();
              
            
!
999px

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