The AGI Common Entity Library is a set of objects and interfaces designed to allow for the easy representation of real-time or simulated data. It is the foundation on which all RT3 components are built. It allows for common location, orientation and graphical information to be stored, and also provides a system for arbitrary metadata to be associated with an entity.
We use the term entity to refer to any single element in a real-time data stream; this could be a moving point such as an aircraft, or a polygonal shape such as a cloud. The term also applies to landscape features such as a bridge or building as well as non-physical elements such as an error or alert. In RT3, all of these elements are just entity objects, a generalization that affords greater flexibility in data manipulation.
For a fully detailed view of all objects, interfaces, and their members, see RT3 Object Model Reference.
STK 11.2.1 Programming Interface