should be painting a radial gradient from center....

final.js

var canvas = document.querySelector('canvas')
var width = canvas.width
var height= canvas.height
var center = [width / 2, height / 2]
var maxd = 100//distance([0,0], center)

return function (r, w) {
  var date = Date.now()
  for (var y = 0; y < height; ++y) {
    for (var x = 0; x < width; ++x) {
        var index = (y * width + x) * 4;

        var a = Math.abs(angle([x, y], center)) / Math.PI
        var z = .05
        var v = Math.abs(Math.sin(date))
        var g = (a < v + z && a > v - z) ? 1 : 0
        var g = a * v% z > z/2 ? 1 : 0
        var t = 1//test([x, y])

        var value = x * y * a * v & 0xff;

        w.data[index]   = r.data[index] * g;    // red
        w.data[++index] = r.data[index] + value * t * g;    // green
        w.data[++index] = r.data[index] * g;    // blue
        w.data[++index] = 255;      // alpha
    }
  }
}


function test(c){
  if(c[0] < width / 2 && c[1] < height / 2) return 1
  else return 0
}

  function angle ( point1, point2 ) {
    var dx = point2[0] - point1[0];
    var dy = point2[1] - point1[1];
    return Math.atan2( dy, dx );
  }


function distance(a, b){
  return Math.sqrt(Math.pow(b[0] - a[0], 2) + Math.pow(b[1] - a[1], 2)) 
}

gistfile1.txt

var canvas = document.querySelector('canvas')
var width = canvas.width
var height= canvas.height
var center = [width / 2, height / 2]
var maxd = 100//distance([0,0], center)

return function (r, w) {
for (var y = 0; y < height; ++y) {
    for (var x = 0; x < width; ++x) {
        var index = (y * width + x) * 4;

        var value = x * y / Math.floor(Date.now() % 256/2) & 0xff;

        w.data[index]   = value;    // red
        w.data[++index] = value;    // green
        w.data[++index] = value;    // blue
        w.data[++index] = 255;      // alpha
    }
}
}


function test(c){
  if(c[0] < width / 2 && c[1] < height / 2) return 1
  else return 0
}

  function angle ( point1, point2 ) {
    var dx = point2[0] - point1[0];
    var dy = point2[1] - point1[1];
    return Math.atan2( dy, dx );
  }


function distance(a, b){
  return Math.sqrt(Math.pow(b[0] - a[0], 2) + Math.pow(b[1] - a[1], 2)) 
}

index.js

var canvas = document.querySelector('canvas')
var width = canvas.width
var height= canvas.height
var center = [width / 2, height / 2]
var maxd = distance([0,0], center)

return function (r, w) {

  for (var i = 0; i < w.data.length; i += 4) {
    var coords = [i / 4 % width, i / 4 % height ]
    var dist = distance(coords, center)
    var v = Math.floor(dist / maxd * 255)/255
    w.data[i] = r.data[i] / v;
    w.data[i+1] =  r.data[i+1] / v;
    w.data[i+2] =  r.data[i + 2] / v;
    w.data[i+3] = 255;
  }
}

function distance(a, b){
  return Math.sqrt(Math.pow(b[0] - a[0], 2) + Math.pow(b[1] - a[1], 2)) 
}

viz.js

var canvas = document.querySelector('canvas')
var width = canvas.width
var height= canvas.height
var center = [width / 2, height / 2]
var maxd = distance([0,0], center)

return function (r, w) {

  for (var i = 0; i < w.data.length; i += 4) {
    var coords = [i / 4 % width, i / 4 % height ]
    var dist = distance(coords, center)
    var v = Math.floor(dist / maxd * 255)
    w.data[i] = v;
    w.data[i+1] =  v;
    w.data[i+2] =  v;
    w.data[i+3] = 255;
  }
}

function distance(a, b){
  return Math.sqrt(Math.pow(b[0] - a[0], 2) + Math.pow(b[1] - a[1], 2)) 
}

xindex.js

var canvas = document.querySelector('canvas')
var width = canvas.width
var height= canvas.height
var center = [width / 2, height / 2]
var maxd = 100//distance([0,0], center)

return function (r, w) {
  for (var y = 0; y < height; ++y) {
    for (var x = 0; x < width; ++x) {
        var index = (y * width + x) * 4;

        var a = Math.abs(angle([x, y], center)) / Math.PI
        var g = a < .1 ? 1 : 0
        var t = test([x, y])

        var value = x * y & 0xff;

        w.data[index]   = value * t * g;    // red
        w.data[++index] = value * t * g;    // green
        w.data[++index] = value * t;    // blue
        w.data[++index] = 255;      // alpha
    }
  }
}


function test(c){
  if(c[0] < width / 2 && c[1] < height / 2) return 1
  else return 0
}

  function angle ( point1, point2 ) {
    var dx = point2[0] - point1[0];
    var dy = point2[1] - point1[1];
    return Math.atan2( dy, dx );
  }


function distance(a, b){
  return Math.sqrt(Math.pow(b[0] - a[0], 2) + Math.pow(b[1] - a[1], 2)) 
}