Description

each IFC model shall have a maximum of 2 (and minimum of 1) instances of IfcGeometricRepresentationContext. The conventions to use the ContextType attributes are:

• IfcGeometricRepresentationContext.ContextType = 'Model' for all but annotations
• IfcGeometricRepresentationContext.ContextType = 'Plan' for annotations

Differentiation of Model representation context (to allow a better structured export) is supported by using IfcGeometricRepresentationSubContext. The conventions to use the ContextType attributes are:

• an IfcGeometricRepresentationContext.ContextType = 'Model' may have subcontexts.
  • the IfcGeometricRepresentationSubContext.ContextIdentifier should be: 'Box', 'Axis', 'FootPrint', 'Profile', 'Body'
  • it refers to the IfcShapeRepresentation.RepresentationIdentifier of the included object geometry

[added 05-05-2006]
Differentiation of Plan representation context (to allow a better structured export) is supported by using IfcGeometricRepresentationSubContext. The conventions to use the ContextType attributes are:

• an IfcGeometricRepresentationContext.ContextType = 'Plan' may have subcontexts.
  • the IfcGeometricRepresentationSubContext.ContextIdentifier should be: 'Annotation'
  • required information (to allow the scaling of annotations, like line types, hatching, text) is the TargetScale attribute, it always has to be provided.
  • the TargetView attribute is always set to .PLAN_VIEW.

[added 06-07-2011]
The following agreement applies to the IFC2x3 CoordinationView V2.0

• an IfcGeometricRepresentationContext with ContextType = 'Model' shall be included
• it shall have a minimum of one sub context, being IfcGeometricRepresentationSubContext.ContextIdentifier = 'Body', and depending on the contained shape representations additional sub contexts 'Box', 'Axis', 'FootPrint', 'Profile'
• all shape representations shall be assigned to the correct IfcGeometricRepresentationSubContext and none to the main IfcGeometricRepresentationContext