D3 Examples - d3 sankey demo; Highlight all connecting paths of a node

xxxxxxxxxx
 
<!DOCTYPE html>
<html>
<meta charset="utf-8">
<title>Sankey Diagram</title>
<style>
 
@import url(https://fonts.googleapis.com/css?family=PT+Serif|PT+Serif:b|PT+Serif:i|PT+Sans|PT+Sans:b);
 
#chart {
  height: 500px;
}
 
.node rect {
  cursor: move;
  fill-opacity: .9;
  shape-rendering: crispEdges;
}
 
.node text {
  pointer-events: none;
  text-shadow: 0 1px 0 #fff;
}
 
.link {
  fill: none;
  stroke: #000;
  stroke-opacity: .2;
}
 
.link:hover {
  stroke-opacity: .5 !important;
}
 
</style>
<body>
​
<div id="chart"></div>
​
<script src="https://d3js.org/d3.v3.min.js?2.9.1"></script>
<script src="sankey.js"></script>
<script>
 
var margin = {top: 1, right: 1, bottom: 6, left: 1},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;
 
var formatNumber = d3.format(",.0f"),
    format = function(d) { return formatNumber(d) + " TWh"; },
    color = d3.scale.category20();
 
var svg = d3.select("#chart").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");
 
var sankey = d3.sankey()
    .nodeWidth(15)
    .nodePadding(10)
    .size([width, height]);
 
var path = sankey.link();
 
d3.json("energy.json", function(energy) {
 
  sankey
      .nodes(energy.nodes)
      .links(energy.links)
      .layout(32);
 
  var link = svg.append("g").selectAll(".link")
      .data(energy.links)
    .enter().append("path")
      .attr("class", "link")
      .attr("d", path)
      .attr("id", function(d,i){
        d.id = i;
        return "link-"+i;
      })
      .style("stroke-width", function(d) { return Math.max(1, d.dy); })
      .sort(function(a, b) { return b.dy - a.dy; });
 
  link.append("title")
      .text(function(d) { return d.source.name + " → " + d.target.name + "\n" + format(d.value); });
 
  var node = svg.append("g").selectAll(".node")
      .data(energy.nodes)
    .enter().append("g")
      .attr("class", "node")
      .attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; })
      .on("click",highlight_node_links)
    .call(d3.behavior.drag()
      .origin(function(d) { return d; })
      // interfering with click .on("dragstart", function() { this.parentNode.appendChild(this); })
      .on("drag", dragmove));
 
  node.append("rect")
      .attr("height", function(d) { return d.dy; })
      .attr("width", sankey.nodeWidth())
      .style("fill", function(d) { return d.color = color(d.name.replace(/ .*/, "")); })
      .style("stroke", function(d) { return d3.rgb(d.color).darker(2); })
    .append("title")
      .text(function(d) { return d.name + "\n" + format(d.value); });
 
  node.append("text")
      .attr("x", -6)
      .attr("y", function(d) { return d.dy / 2; })
      .attr("dy", ".35em")
      .attr("text-anchor", "end")
      .attr("transform", null)
      .text(function(d) { return d.name; })
    .filter(function(d) { return d.x < width / 2; })
      .attr("x", 6 + sankey.nodeWidth())
      .attr("text-anchor", "start");
 
  function dragmove(d) {
    d3.select(this).attr("transform", "translate(" + d.x + "," + (d.y = Math.max(0, Math.min(height - d.dy, d3.event.y))) + ")");
    sankey.relayout();
    link.attr("d", path);
  }
​
  function highlight_node_links(node,i){
​
    var remainingNodes=[],
        nextNodes=[];
​
    var stroke_opacity = 0;
    if( d3.select(this).attr("data-clicked") == "1" ){
      d3.select(this).attr("data-clicked","0");
      stroke_opacity = 0.2;
    }else{
      d3.select(this).attr("data-clicked","1");
      stroke_opacity = 0.5;
    }
​
    var traverse = [{
                      linkType : "sourceLinks",
                      nodeType : "target"
                    },{
                      linkType : "targetLinks",
                      nodeType : "source"
                    }];
​
    traverse.forEach(function(step){
      node[step.linkType].forEach(function(link) {
        remainingNodes.push(link[step.nodeType]);
        highlight_link(link.id, stroke_opacity);
      });
​
      while (remainingNodes.length) {
        nextNodes = [];
        remainingNodes.forEach(function(node) {
          node[step.linkType].forEach(function(link) {
            nextNodes.push(link[step.nodeType]);
            highlight_link(link.id, stroke_opacity);
          });
        });
        remainingNodes = nextNodes;
      }
    });
  }
​
  function highlight_link(id,opacity){
      d3.select("#link-"+id).style("stroke-opacity", opacity);
  }
​
});
 
</script>
    