Purpose & Assumptions

Use as a supplement to the descriptions of the IFC Export Flexible Mappings in the online help, not as a replacement (the examples and guidance concentrate on the choices made while mapping, rather than how to create a mapping at all). There are many ways in which the IFC files can be used, and the IFC elements and properties required can vary greatly, so several possibilities are described and not all will be applicable to particular needs.

Assumptions

The user is generally familiar with:

• The major elements and attributes used in E3D Design Model Databases.

• PML Expressions

• How particular projects are set up, including

  • how to use site and zones

  • how to use any User-Defined-Attributes containing data are to be exported.

• The major elements, attributes and relationships used in IFC data (refer to the Building Smart International article Industry Foundation Classes (IFC) for further information).

  • Spatial structure elements (for example: IfcBuilding)

  • Building elements and similar (for example: IfcBeam)

  • Property sets

  • The schema required (IFC2x3 TC1 or IFC4 ADD2 TC1)

  • The expected Model View Definition

  • Any particular requirements of the consuming applications.

    Notes:
    Most of the comments are applicable to both IFC2x3 and IFC4 schemas, but some are only applicable to one or the other.

    One key point to remember is that the order of the individual mappings is important. Only the first element mapping that matches particular E3D element being exported will be used. Mappings later in the file that could match will not be processed. Therefore put more specific mappings before the more general fallback mappings.