Wrapping Text in D3

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I would like to get the text to wrap on the following D3 tree so that instead of

Foo is not a long word

each line is wrapped to

Foo is
not a
long word

I have tried making the text a ‘foreignObject’ rather than a text object and the text does indeed wrap, but it doesn’t move on the tree animation and is all grouped in the upper left hand corner.

Code located at



var width = 960,
    height = 500;

var tree = d3.layout.tree()
    .size([width - 20, height - 20]);

var root = {},
    nodes = tree(root);

root.parent = root;
root.px = root.x;
root.py = root.y;

var diagonal = d3.svg.diagonal();

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height)
    .attr("transform", "translate(10,10)");

var node = svg.selectAll(".node"),
    link = svg.selectAll(".link");

var duration = 750,
    timer = setInterval(update, duration);

function update() {
  if (nodes.length >= 500) return clearInterval(timer);

  // Add a new node to a random parent.
  var n = {id: nodes.length},
      p = nodes[Math.random() * nodes.length | 0];
  if (p.children) p.children.push(n); else p.children = [n];

  // Recompute the layout and data join.
  node = node.data(tree.nodes(root), function(d) { return d.id; });
  link = link.data(tree.links(nodes), function(d) { return d.source.id + "-" + d.target.id; });

  // Add entering nodes in the parent’s old position.
      .attr("class", "node")
      .attr("x", function(d) { return d.parent.px; })
      .attr("y", function(d) { return d.parent.py; })
        .text('Foo is not a long word');

  // Add entering links in the parent’s old position.
  link.enter().insert("path", ".node")
      .attr("class", "link")
      .attr("d", function(d) {
        var o = {x: d.source.px, y: d.source.py};
        return diagonal({source: o, target: o});

  // Transition nodes and links to their new positions.
  var t = svg.transition()

      .attr("d", diagonal);

      .attr("x", function(d) { return d.px = d.x; })
      .attr("y", function(d) { return d.py = d.y; });


You can modify Mike Bostock’s “Wrapping Long Labels” example to add <tspan> elements to your <text> nodes. There are two major changes required to add wrapped text to your nodes. I didn’t delve into having the text update its position during transitions, but it shouldn’t be too hard to add.

The first is to add a function wrap, based off of the function in the above example. wrap will take care of adding <tspan> elements to make your text fit within a certain width:

function wrap(text, width) {
    text.each(function () {
        var text = d3.select(this),
            words = text.text().split(/s+/).reverse(),
            line = [],
            lineNumber = 0,
            lineHeight = 1.1, // ems
            x = text.attr("x"),
            y = text.attr("y"),
            dy = 0, //parseFloat(text.attr("dy")),
            tspan = text.text(null)
                        .attr("x", x)
                        .attr("y", y)
                        .attr("dy", dy + "em");
        while (word = words.pop()) {
            tspan.text(line.join(" "));
            if (tspan.node().getComputedTextLength() > width) {
                tspan.text(line.join(" "));
                line = [word];
                tspan = text.append("tspan")
                            .attr("x", x)
                            .attr("y", y)
                            .attr("dy", ++lineNumber * lineHeight + dy + "em")

The second change is that instead of setting the text of each node, you need to call wrap for each node:

// Add entering nodes in the parent’s old position.
    .attr("class", "node")
    .attr("x", function (d) { return d.parent.px; })
    .attr("y", function (d) { return d.parent.py; })
    .text("Foo is not a long word")
    .call(wrap, 30); // wrap the text in <= 30 pixels

Source: stackoverflow