Entity Base

Parent module: Root Entities Module

group a3d_rootbase

Creates and accesses a hierarchy of descriptive names and modeller data that can be applied to any PRC entity.

Entity type is kA3DTypeRootBase

This module lets you create a hierarchy of descriptive names and modeller data (called root-level attributes) that can be applied to any PRC entity. These attributes are packaged as an A3DRootBase entity that is referenced from the PRC entity they describe.

The following sample code shows how to create root-level attributes for any PRC entity. In this case, the attributes include modeller data. For restrictions on specifying modeller data, see A3DMiscAttributeData.

A3DVoid setAttributes(A3DEntity* p)
    A3DMiscAttribute* pAttr[3];

    A3DMiscSingleAttributeData Single;

    Single.m_eType = kA3DModellerAttributeTypeString;
    Single.m_pcTitle = "Title";
    Single.m_pcData = "Simple B-rep building demonstration";

    A3DMiscAttributeData sAttribs;

    sAttribs.m_pcTitle = Single.m_pcTitle;
    sAttribs.m_asSingleAttributesData = &Single;
    sAttribs.m_uiSize = 1;
    A3DInt32 iRet = A3DMiscAttributeCreate(&sAttribs, &pAttr[0]);

    Single.m_pcTitle = "Author";
    Single.m_pcData = "HOOPS Exchange";
    sAttribs.m_pcTitle = Single.m_pcTitle;
    iRet = A3DMiscAttributeCreate(&sAttribs, &pAttr[1]);

    Single.m_pcTitle = "Company";
    Single.m_pcData = "Tech Soft 3D";
    sAttribs.m_pcTitle = Single.m_pcTitle;
    iRet = A3DMiscAttributeCreate(&sAttribs, &pAttr[2]);

    A3DRootBaseData sRootData;

    sRootData.m_pcName = "Trimmed surface";
    sRootData.m_ppAttributes = pAttr;
    sRootData.m_uiSize = 3;
    iRet = A3DRootBaseSet(p, &sRootData);
    // cleaning up the allocated attributes
    for(A3DUns32 i = 0; i < sRootData.m_uiSize; ++i)

The following illustration shows the result of the sample code.

The sample code creates an A3DRootBase entity that houses three A3DMiscAttribute entities, each of which reference an A3DMiscSingleAttributeData structure. Each A3DMiscSingleAttributeData structure provides modeller data of type kA3DModellerAttributeTypeString.



Miscellaneous Attribute Entity

Creates and accesses descriptive names and modeller data associated with PRC entities.

Data Structures


A structure representing a hierarchy of descriptive names and modeler data that applies to any PRC entity.



Populates an A3DRootBaseData structure with the data from a PRC entity.


Adds an A3DRootBaseData structure to an existing PRC entity.


Remove all attributes stored in a PRC entity.


Remove attribute in the attribute array of PRC entity with a specific title.


Remove attribute of the current attribute array stored in a PRC entity, at a specific position.


Append attributes to the current attribute array stored in a PRC entity.


Add an attribute to the current attribute array stored in a PRC entity.