VisualItem.FILLCOLOR, ColorLib.rgb(200,200,255));
fill.add("_fixed", ColorLib.rgb(255,100,100));
fill.add("_highlight", ColorLib.rgb(255,200,125));
ForceDirectedLayout fdl = new ForceDirectedLayout(graph);
ForceSimulator fsim = fdl.getForceSimulator();
fsim.getForces()[0].setParameter(0, -1.2f);
ActionList animate = new ActionList(Activity.INFINITY);
animate.add(fdl);
animate.add(fill);
animate.add(new RepaintAction());