public void initialize() {
   super.initialize();
   if (numberOfAgents() > 0) myViewer.updateWorldData((Patch[][]) getObject(getAgentNb(0)));
   System.err.println(this);
 }
 public void update(AbstractAgent theAgent, boolean added) {
   super.update(theAgent, added);
   if (added) myViewer.updateWorldData((Patch[][]) getObject(theAgent));
   System.err.println(this);
 }