Classes
From DocR21
The class interface is a set of C++ classes that are used to define the ACIS model geometry and topology, as well as control the behavior the various modeling operations. The classes may be used by an application to directly interact with ACIS through their public and protected data members and methods (member functions). Refer to the ACIS classes in the Library Reference for summaries and reference templates and a detailed description of each.
The class ENTITY is a base class from which many ACIS classes are derived. It implements common data and functionality that is mandatory in all classes that represent persistent objects in the model, although ENTITY does not itself represent any specific object. The ATTRIB class, which is derived from ENTITY, is used to derive specific attribute classes for system and user attributes. Refer to the section Attributes for information.
Developers may also derive application-specific classes from the ENTITY and ATTRIB classes for special purposes. Refer to the Deriving Classes and Attribute Derivation technical articles for details about deriving classes from ENTITY and ATTRIB.
In addition to the persistent classes derived from ENTITY, ACIS uses myriad classes to represents containers, construction geometry, global options, function arguments, auxiliary data structures, etc. Moreover, many of the modeling algorithms in ACIS are Object Oriented. In short, C++ classes form the foundation of ACIS.
