Personal tools
You are here: Home / Specifications / MVD Releases / IFC4 Design Transfer View / IFC4 DTV Objectives

IFC4 DTV Objectives

merged BIM 2

--

IFC4 Design Transfer View

The IFC4 Design Transfer View targets work flows that allow further editing by design software platforms. Read more:

 

Objective of the IFC4 Design Transfer View

The main objective of the IFC4 Design Transfer View is to enable collaboration on design elements impacting multiple disciplines. The second objective is to provide a capability to hand over design models to others. The hand over is limited to the extend of parametric capabilities currently built-in IFC with the focus on dimension-driven standard case elements. The support of round-trip scenarios is excluded from the scope of the Design Transfer View.

The IFC4 Design Transfer View is an add-on view to the IFC4 Reference View. It includes the semantic building data being defined in the IFC4 Reference View:

  • physical elements with explicit geometry, properties, quantities, material, and classification
  • types of elements with associated physical elements to group common definitions (geometry, properties, material, and classification)
  • spatial elements (spaces, zones) with explicit geometry, properties, quantities, and classification
  • spatial structure elements (site, building, story), but also spatial zones for non-vertical construction
  • element breakdown structure between physical elements (assemblies, sub-assemblies, parts)
  • spatial breakdown structure between spatial elements (spatial decomposition of building, story or zones)
  • spatial containment structure between spatial elements and physical elements (elements in spatial zone)
  • logical system structure and assignment (physical elements assigned to systems and sub systems)
  • topological structure of system networks (element to port, and port to port, relationship)
  • common context of the building model, providing units, coordinate system and GIS positions
  • general object identification using globally unique identifier

It adds to it:

  • full geometric capabilities, including advanced sweeps, faceted and advanced B-rep, and CSG
  • parameterized profile definitions
  • standard case and elemented case definitions of main building elements
  • material definitions with dimensions and alignment to reference geometry (layer sets, profile sets)
  • material based presentation styles
  • library definitions and references
  • property set definition templates
  • element based revision control (owner history)
Workflow support by the IFC4 Design Transfer View

The overall goal of the IFC4 Design Transfer View is to provide work flows where building information models may be edited by design software platforms. It is not intended to capture all design parameters, but rather a limited subset affecting major building elements, along with the design results for all components within a building.

To support the best way to exchange rich geometry preserving parameters, the resulting schema includes several additional geometry types, such as advanced B-rep (NURBS), faceted B-rep and surface models, Constructed solid geometry (CSG), and advanced sweeps, including tapering. presentation styles, such as colors and textures, can be added to these geometries.

Compatibility Concerns for the IFC4 Design Transfer View

The IFC4 Design Transfer View is the successor of the IFC2x3 Coordination View. The Design transfer View is intended to be compatible with the IFC2x3 Coordination View for import. Exceptions to compatibility are made for the export to support new features and remove obsolete data structures.

The second Model View Definition that is proposed in parallel to the IFC4 Reference View, the IFC4 Design Transfer View, is an extension of this model view. In other words, the IFC4 Reference View is a true subset of the IFC4 Design Transfer View.

Complying software interfaces, that implements import of the IFC4 Design Transfer View, shall also be able to correctly import IFC4 Reference View data sets. But not vice versa, a complying software interface, that implements import of the IFC4 Reference View will not be capable to import IFC4 Design Transfer View data sets. It is however required that a compliant software interface for importing IFC4 Reference View displays an agreed error message showing the IFC version, and the IFC Model View Definition of the imported IFC file, that does not match "IFC4 Reference View" with an explanation, that a non-compatible IFC file has been received.

NOTE The correct error message and the link to further information on the buildingSMART website explaining the purpose of the different IFC Model View Definitions need to be agreed upon.
See next chapter Scope for more details.