code: function(par, id){
      if (par.angleSpan) {
        var adjs = [];
        par.eachAdjacency(function(elem){
          adjs.push(elem.nodeTo);
        }, "ignore");
        var len = adjs.length;
        for ( var i = 0; i < len && id != adjs[i].id; i++)
          ;
        for ( var j = (i + 1) % len, k = 0; id != adjs[j].id; j = (j + 1) % len) {
          adjs[j].dist = k++;
        }
      }
    }
docs: /*
  tagChildren
  
  Enumerates the children in order to maintain child ordering (second constraint of the paper).