как обновлять ветки в d3 js

Question

При добавлении polygon в схему не получается обновлять ветки, новые ветки наслаиваются на старые. Как решить эту проблему? Код веток

           // Update the links…
            var link = vis.selectAll("path.link")
                .data(tree.links(nodes), function(d) { return d.target.id; });

            // Enter any new links at the parent's previous position.
            link.enter().insert("svg:polygon", "g")
                .attr("class", "link")
                .attr("points", function(d){
                  console.log(d.target);
                  var y1 = d.source.x + linkWidth(d.target);
                  var y2 = d.source.x - linkWidth(d.target);
                  return   d.source.y +" "+ y1 + ", " + d.source.y +" "+ y2 + ", "  + d.target.y +" "+ d.target.x; 
                  /*var w1 = 50;
                  var retur = "";
                  var x3;
                  x3 = d.source.x;
                  //y = d.sourse.y;
                  while( (x3 != d.target.x) && (d.source.y != d.target.y)){
                    if((d.source.x - d.target.x) > 0) {
                      var y1 = d.source.y + w1;
                      var y2 = d.source.y - w1; 
                      retur = retur + " " +  y1 + " " + x3 +  ", " + y2 + " " + x3 + ", ";
                      x3 = x3 - 1;
                      w1--;
                    } else {
                      var y1 = d.source.y + w1;
                      var y2 = d.source.y - w1; 
                      retur = retur + " " + y1 + " " + x3 + ", " + y2 + " " + x3 + ", ";
                      x3 = x3 + 1;
                      w1--;
                    }
                  }
                //console.log(retur + "11111111111111111111111111");
                return retur;*/
                })
                /*.attr("d", function(d) {
                    var o = {x: source.x0, y: source.y0};
                    return connector({source: o, target: o});
                })*/
                .style("fill","#AAA")
                .style("stroke", self.settings.lineColor)
                .transition()
                .duration(duration);


            function linkWidth(d) { 
              var depth = d.depth; 
              if (d.name !== '' && d.children && d.children.length === 1 && d.children[0].name === '') { 
              depth += 1; 
              } 
              return Math.max(5 - 2*depth, 1.5); 
              }
            // Transition links to their new position.
            link.transition()
                .duration(duration);


            // Transition exiting nodes to the parent's new position.
           link.exit().transition()
                .duration(duration)
            .attr("points", function(d) {
                  var y1 = d.source.x + linkWidth(d.target);
                  var y2 = d.source.x - linkWidth(d.target);
                  return   d.source.y +" "+ y1 + ", " + d.source.y +" "+ y2 + ", "  + d.target.y +" "+ d.target.x; 
                })
                .remove();