0;e<b.length;e++){k=b[e];d=[];for(f in k)d.push(k[f]);this.model=new mxGraphHierarchyModel(this,d,this.roots,a,this.tightenToSource);this.cycleStage(a);this.layeringStage();this.crossingStage(a);c=this.placementStage(c,a)}};