Domain objects for use in a freeform graphics system. Domain objects are
context specific representations of information that are used in a
freeform graphics system. Domain objects are represented in a freeform
graphics system by a graphic object (icon) representing an instance of the
domain object. The icon representing a domain object may be manipulated
like any other graphic object. Domain objects are defined by a domain
object class which define attributes, a set of action rules and layouts.
The attributes describe the information or data associated with the domain
object. The set of action rules map user actions and system events to
operations that may be performed on the domain object. The layouts define
how domain object information is displayed as an icon.