title: Hide label if not enough space D3 Zoomable Sunburst chart
body: <p>So I know this answer is here to hide text that will not fit in the chart: <a href="https://stackoverflow.com/questions/19792552/d3-put-arc-labels-in-a-pie-chart-if-there-is-enough-space">D3 put arc labels in a Pie Chart if there is enough space</a></p>
  
  <p>But I can't figure out how to introduce this into the code below. I've edited this code to make it so you only see uptil the second inner circle when viewing. But even then, lots of labels do not have enough space to fit in their respective slice. So I'd like to add more logic, just to check if the text can fit.</p>
  
  <p>Or something even simpler would be if the slice doesn't take up at least 10% of the partition of the whole circle it's in, then hide it. </p>
  
  <p>Here is the JS fiddle: </p>
  
  <p><a href="http://jsfiddle.net/P79kX/" rel="nofollow noreferrer">http://jsfiddle.net/P79kX/</a>
  This is not a perfect JSFiddle, and it doesn't reflect my code exactly. But the concept is the same, check the bounding box.</p>
  
  <p>Here is the code: </p>
  
  <pre><code>var width = 840,
      height = width,
      radius = width / 2,
      x = d3.scale.linear().range([0, 2 * Math.PI]),
      y = d3.scale.pow().exponent(1.3).domain([0, 1]).range([0, radius]),
      padding = 5,
      duration = 1000;
  
  var div = d3.select("#chart_render");
  
  div.select("img").remove();
  
  var vis = div.append("svg")
      .attr("width", width + padding * 2)
      .attr("height", height + padding * 2)
    .append("g")
      .attr("transform", "translate(" + [radius + padding, radius + padding] + ")");
  
  var partition = d3.layout.partition()
      .sort(null)
      .value(function(d) { return d.size });
  
  var arc = d3.svg.arc()
      .startAngle(function(d) { return Math.max(0, Math.min(2 * Math.PI, x(d.x))); })
      .endAngle(function(d) { return Math.max(0, Math.min(2 * Math.PI, x(d.x + d.dx))); })
      .innerRadius(function(d) { return Math.max(0, d.y ? y(d.y) : d.y); })
      .outerRadius(function(d) { return Math.max(0, y(d.y + d.dy)); });
  
  d3.json("/js/wheel.json", function(error, json) {
    console.log(json);
    var nodes = partition.nodes({children: json});
  
    var path = vis.selectAll("path").data(nodes);
    path.enter().append("path")
        .attr("id", function(d, i) { return "path-" + i; })
        .attr("d", arc)
        .attr("fill-rule", "evenodd")
        .style("fill", colour)
        .on("click", click);
  
    var text = vis.selectAll("text").data(nodes);
    var textEnter = text.enter().append("text")
        .style("fill-opacity", function(d) {
          if (d.depth &gt; 2) {
            return '0';
          } else {
            return '1';
          }
        })
        .style("fill", function(d) {
          return "#fff";
        })
        .attr("text-anchor", function(d) {
          return x(d.x + d.dx / 2) &gt; Math.PI ? "end" : "start";
        })
        .attr("dy", ".2em")
        .attr("transform", function(d) {
          var multiline = (d.name || "").split(" ").length &gt; 1,
              angle = x(d.x + d.dx / 2) * 180 / Math.PI - 90,
              rotate = angle + (multiline ? -.5 : 0);
          return "rotate(" + rotate + ")translate(" + (y(d.y) + padding) + ")rotate(" + (angle &gt; 90 ? -180 : 0) + ")";
        })
        .on("click", click);
    textEnter.append("tspan")
        .attr("x", 0)
        .text(function(d) { return d.depth ? d.name.split(" ")[0] : ""; });
    textEnter.append("tspan")
        .attr("x", 0)
        .attr("dy", "1em")
        .text(function(d) { return d.depth ? d.name.split(" ")[1] || "" : ""; });
  
    function click(d) {
      path.transition()
        .duration(duration)
        .attrTween("d", arcTween(d));
  
      // Somewhat of a hack as we rely on arcTween updating the scales.
      text.style("visibility", function(e) {
            return isParentOf(d, e) &amp;&amp; e.depth &lt; d.depth + 2 ? null : d3.select(this).style("visibility");
          })
        .transition()
          .duration(duration)
          .attrTween("text-anchor", function(d) {
            return function() {
              return x(d.x + d.dx / 2) &gt; Math.PI ? "end" : "start";
            };
          })
          .attrTween("transform", function(d) {
            var multiline = (d.name || "").split(" ").length &gt; 1;
            return function() {
              var angle = x(d.x + d.dx / 2) * 180 / Math.PI - 90,
                  rotate = angle + (multiline ? -.5 : 0);
              return "rotate(" + rotate + ")translate(" + (y(d.y) + padding) + ")rotate(" + (angle &gt; 90 ? -180 : 0) + ")";
            };
          })
          .style("fill-opacity", function(e) { return isParentOf(d, e) ? 1 : 1e-6; })
          .each("end", function(e) {
            d3.select(this).style("visibility", isParentOf(d, e) &amp;&amp; e.depth &lt; d.depth + 2 ? null : "hidden");
          });
    }
  });
  
  function isParentOf(p, c) {
    if (p === c) return true;
    if (p.children) {
      return p.children.some(function(d) {
        return isParentOf(d, c);
      });
    }
    return false;
  }
  
  function colour(d) {
  
    if (d.depth == 0) {
      return "rgb(250, 250, 250)";
    } else if (d.depth == 1) {
      return 'rgb(86, 135, 209)';
    } else if (d.depth == 2) {
      return 'rgb(222, 120, 59)';
    } else if (d.depth == 3) {
      return 'rgb(106, 185, 117)';
    }
  
    // if (d.children) {
    //   // There is a maximum of two children!
    //   var colours = d.children.map(colour),
    //       a = d3.hsl(colours[0]),
    //       b = d3.hsl(colours[1]);
    //   // L*a*b* might be better here...
    //   return d3.hsl((a.h + b.h) / 2, a.s * 1.2, a.l / 1.2);
    // }
    // return d.colour || "#fff";
  }
  
  // Interpolate the scales!
  function arcTween(d) {
    var my = maxY(d),
        xd = d3.interpolate(x.domain(), [d.x, d.x + d.dx]),
        yd = d3.interpolate(y.domain(), [d.y, my]),
        yr = d3.interpolate(y.range(), [d.y ? 20 : 0, radius]);
    return function(d) {
      return function(t) { x.domain(xd(t)); y.domain(yd(t)).range(yr(t)); return arc(d); };
    };
  }
  
  function maxY(d) {
    return d.children ? Math.max.apply(Math, d.children.map(maxY)) : d.y + d.dy;
  }
  
  // http://www.w3.org/WAI/ER/WD-AERT/#color-contrast
  function brightness(rgb) {
    return rgb.r * .299 + rgb.g * .587 + rgb.b * .114;
  }
  </code></pre>