Rotating text paths in d3.js chord diagram without usual svg:text

Question

I am trying to adapt this Chord diagram by Mike Bostock:

I want to have the text labels rotating outwards like this chord diagram:

http://bost.ocks.org/mike/uberdata/

There is an example here

http://bl.ocks.org/mbostock/910126

However, the transformation is done using the svg:text :

  g.append("svg:text")
      .each(function(d) { d.angle = (d.startAngle + d.endAngle) / 2; })
      .attr("dy", ".35em")
      .attr("text-anchor", function(d) { return d.angle > Math.PI ? "end" : null; })
      .attr("transform", function(d) {
        return "rotate(" + (d.angle * 180 / Math.PI - 90) + ")"
            + "translate(" + (r0 + 26) + ")"
            + (d.angle > Math.PI ? "rotate(180)" : "");
      })
      .text(function(d) { return nameByIndex[d.index]; });

The one I am trying to adapt uses "text" and "textPath" and I don't seem to be able to simply add a transform/rotate attribute. Adding this line

.attr("transform",function(d,i){return "rotate(90)";})

to the code below does nothing:

   // Add a text label.
        var groupText = group.append("text")
            .attr("x", 6)
            .attr("dy", 15);

            groupText.append("textPath")
            .attr("xlink:href",  function(d, i) { return "#group" + i; })

           .text(function(d, i) { return cities[i].country; });

Any ideas how I can rotate the text outwards so smaller chord groups text labels can be displayed without being bunched up or (as is the orginal solution) turned off altogether?

Answer 1

I think you are looking for this example by Mike Bostock

As far as modifying the initial chord code, the following change should do what you want:

// Add a text label.
// var groupText = group.append("text")
//     .attr("x", 6)
//     .attr("dy", 15);

//groupText.append("textPath")
//    .attr("xlink:href", function(d, i) { return "#group" + i; })
//    .text(function(d, i) { return cities[i].name; });

// Remove the labels that don't fit. :(
//groupText.filter(function(d, i) { return groupPath[0][i].getTotalLength() / 2 - 16 < this.getComputedTextLength(); })
//    .remove();

group.append("text")
  .each(function(d) { d.angle = (d.startAngle + d.endAngle) / 2; })
  .attr("dy", ".35em")
  .attr("transform", function(d) {
    return "rotate(" + (d.angle * 180 / Math.PI - 90) + ")"
        + "translate(" + (innerRadius + 26) + ")"
        + (d.angle > Math.PI ? "rotate(180)" : "");
  })
  .style("text-anchor", function(d) { return d.angle > Math.PI ? "end" : null; })
  .text(function(d, i) { return cities[i].name; });