Overview

Programming Guide

API Reference

A3DTopoContextData Struct Reference

Structure for parsing or creating an A3DTopoContext entity. More...

Data Fields

A3DUns16 m_usStructSize
 
A3DUns8 m_ucBehaviour
 
A3DDouble m_dGranularity
 
A3DDouble m_dTolerance
 
A3DBool m_bHaveSmallestFaceThickness
 
A3DDouble m_dSmallestThickness
 
A3DBool m_bHaveScale
 
A3DDouble m_dScale
 

Detailed Description

Structure for parsing or creating an A3DTopoContext entity.

Version
2.0

The m_ucBehaviour member is a array of bits that uses values from the topology context bitmask definitions (Topology Context Data).

Note
m_dScale is a conversion factor from the unit of the part (which is not mandatory millimeters) to the "unit" of the modeling kernel. In fact, there is NO notion of physical unit at the level of the "TopoContext". The numbers that are stored there do not have a physical significance by themselves. To interpret them, you should take into account the unit of the part and the "TopoContext" context scale. See the ISO doc chapter 2.6 and 2.7 for further explanation. Then, there can be further scale on the product hierarchy that should be taken into account when converting entities while respecting a given accuracy towards original geometry.
See also
A3DTopoContextData, A3DTopoContextGet, A3DTopoContextCreate

Field Documentation

A3DUns16 A3DTopoContextData::m_usStructSize

Reserved; must be initialized with A3D_INITIALIZE_DATA.

A3DUns8 A3DTopoContextData::m_ucBehaviour

Array of bits.

A3DDouble A3DTopoContextData::m_dGranularity

Minimal size of an edge. This value is non-dimensional.

A3DDouble A3DTopoContextData::m_dTolerance

Global base tolerance used in the context for topological elements. This value is non-dimensional.

A3DBool A3DTopoContextData::m_bHaveSmallestFaceThickness

True if next member is valid.

A3DDouble A3DTopoContextData::m_dSmallestThickness

Smallest thickness for a face. Used in internal loop treatment. Default should be 100 * m_dGranularity.

A3DBool A3DTopoContextData::m_bHaveScale

True if next member is valid.

A3DDouble A3DTopoContextData::m_dScale

Optional scale to interpret the data of the context.