D3 Treemap Exploration

by Geo George

HTML

<script src="//d3js.org/d3.v3.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/d3-tip/0.6.3/d3-tip.min.js"></script>
<div id="body">
      <div id="footer">
        d3.layout.treemap
        <div class="hint">click or option-click to descend or ascend</div>
        <div><select>
          <option value="size">Size</option>
          <option value="count">Count</option>
        </select></div>
      </div>
    </div>

CSS

.chart {
  display: block;
  margin: auto;
  margin-top: 40px;
}

text {
  font-size: 11px;
}

rect {
  fill: none;
}

JavaScript

var w = 1280 - 80,
    h = 800 - 180,
    x = d3.scale.linear().range([0, w]),
    y = d3.scale.linear().range([0, h]),
    color = d3.scale.category20c(),
    root,
    node;

var treemap = d3.layout.treemap()
    .round(false)
    .size([w, h])
    .sticky(true)
    .value(function(d) { return d.size; });

var svg = d3.select("#body").append("div")
    .attr("class", "chart")
    .style("width", w + "px")
    .style("height", h + "px")
  .append("svg:svg")
    .attr("width", w)
    .attr("height", h)
  .append("svg:g")
    .attr("transform", "translate(.5,.5)");

d3.json("http://mbostock.github.io/d3/talk/20111018/flare.json", function(data) {
  node = root = data;

  var nodes = treemap.nodes(root)
      .filter(function(d) { return !d.children; });

  var cell = svg.selectAll("g")
      .data(nodes)
    .enter().append("svg:g")
      .attr("class", "cell")
      .attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; })
      .on("click", function(d) { return zoom(node == d.parent ? root : d.parent); });

  cell.append("svg:rect")
      .attr("width", function(d) { return d.dx - 1; })
      .attr("height", function(d) { return d.dy - 1; })
      .style("fill", function(d) { return color(d.parent.name); });

  cell.append("svg:text")
      .attr("x", function(d) { return d.dx / 2; })
      .attr("y", function(d) { return d.dy / 2; })
      .attr("dy", ".35em")
      .attr("text-anchor", "middle")
      .text(function(d) { return d.name; })
      .style("opacity", function(d) { d.w = this.getComputedTextLength(); return d.dx > d.w ? 1 : 0; });

  d3.select(window).on("click", function() { zoom(root); });

  d3.select("select").on("change", function() {
    treemap.value(this.value == "size" ? size : count).nodes(root);
    zoom(node);
  });
  addTooltip();
});

function size(d) {
  return d.size;
}

function count(d) {
  return 1;
}

function zoom(d) {
  var kx = w / d.dx, ky = h / d.dy;
  x.domain([d.x, d.x + d.dx]);
  y.domain([d.y, d.y...