General Update Pattern, III

_.md

[ Launch: General Update Pattern, III ] 5033213 by benolee

config.json

{"description":"General Update Pattern, III","endpoint":"","display":"svg","public":true,"require":[],"fileconfigs":{"inlet.js":{"default":true,"vim":false,"emacs":false,"fontSize":12},"style.css":{"default":true,"vim":false,"emacs":false,"fontSize":12}},"fullscreen":false,"play":false,"loop":false,"restart":false,"autoinit":true,"pause":true,"loop_type":"period","bv":false,"nclones":15,"clone_opacity":0.4,"duration":3000,"ease":"linear","dt":0.01}

inlet.js

var alphabet = "abcdefghijklmnopqrstuvwxyz".split("");

var width = 960,
    height = 500;

var svg = d3.select("svg")
    .attr("width", width)
    .attr("height", height)
  .append("g")
    .attr("transform", "translate(32," + (height / 2) + ")");

function update(data) {

  // DATA JOIN
  // Join new data with old elements, if any.
  var text = svg.selectAll("text")
      .data(data, function(d) { return d; });

  // UPDATE
  // Update old elements as needed.
  text.attr("class", "update")
    .transition()
      .duration(750)
      .attr("x", function(d, i) { return i * 32; });

  // ENTER
  // Create new elements as needed.
  text.enter().append("text")
      .attr("class", "enter")
      .attr("dy", ".35em")
      .attr("y", -60)
      .attr("x", function(d, i) { return i * 32; })
      .style("fill-opacity", 1e-6)
      .text(function(d) { return d; })
    .transition()
      .duration(750)
      .attr("y", 0)
      .style("fill-opacity", 1);

  // EXIT
  // Remove old elements as needed.
  text.exit()
      .attr("class", "exit")
    .transition()
      .duration(750)
      .attr("y", 60)
      .style("fill-opacity", 1e-6)
      .remove();
}

// The initial display.
update(alphabet);

// Grab a random sample of letters from the alphabet, in alphabetical order.
setInterval(function() {
  update(shuffle(alphabet)
      .slice(0, Math.floor(Math.random() * 26))
      .sort());
}, 1500);

// Shuffles the input array.
function shuffle(array) {
  var m = array.length, t, i;
  while (m) {
    i = Math.floor(Math.random() * m--);
    t = array[m], array[m] = array[i], array[i] = t;
  }
  return array;
}

style.css

text {
  font: bold 48px monospace;
}

.enter {
  fill: green;
}

.update {
  fill: #333;
}

.exit {
  fill: brown;
}