# SUBSYSTEM OVERVIEW

S046 Interface (S046) Subsystem

The S046 subsystem provides functions specific to the Part 46 Resource Model. The S046 subsystem provides STEP dependent functions for creation of certain attribute-specific Part 46 entities. Some of these entities include color and curve style.

# GENERAL CONCEPTS

The s046_Initialize() and s046_Terminate() functions set up the required data structures. The function s046_Initialize must be called once before any other s046 function. The call to s046_Initialize must follow the step_Initialize call. Once processing is complete, the function s046_Terminate should be called prior to calling step_Terminate.

# CREATING PART 46 ENTITIES

Each of the functions take a native attribute entity pointer. This is used to eliminate duplicate STEP entities. If a reference to the native attribute pointer is found, then the corresponding STEP entity pointer is returned. Otherwise, the specific attributes are extracted from the given native entity and the appropriate STEP entity is created.

Two utility functions included in this subsystem aid in the search for duplicates of a given STEP entity type. One function compares tree entries and another resets the cross reference trees by removing all of the entries.