They can either be displayed as a text message next to the entity, or used to change the icon which represents the entity. Only show the value of this parameter. Only show the name of this parameter. The animations are driven by the trace output of the simulation running underneath. There are two types of traces recognised by the animation package, each signified by its first character.
P traces P traces are used to update the display of the entity's parameters.
See also the design document for more details. Thus extra gui components can be added to the display by adding them to the Panel. An example of this is in this text area application which positions TextArea over a couple of the entities. This method can be overidden in the subclass and used to display results. See the simdiag guide for more details of this.