8.8.3.2 IfcAdvancedBrepWithVoids

8.8.3.2.1 Semantic definition

The IfcAdvancedBrepWithVoids is a specialization of an advanced B-rep which contains one or more voids in its interior. The voids are represented as closed shells which are defined so that the shell normal point into the void.

Informal Propositions

Each void shell shall be disjoint from the outer shell and from every other void shell
Each void shell shall be enclosed within the outer shell but not within any other void shell. In particular the outer shell is not in the set of void shells
Each shell in the IfcManifoldSolidBrep shall be referenced only once.
All the faces of all the shells in the IfcAdvancedBrep and the IfcAdvancedBrepWithVoids.Voids shall be of type IfcAdvancedFace.

8.8.3.2.2 Entity inheritance

8.8.3.2.3 Attributes

#	Attribute	Type	Description
IfcRepresentationItem (2)
	LayerAssignment	SET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItems	Assignment of the representation item to a single or multiple layer(s). The LayerAssignments can override a LayerAssignments of the IfcRepresentation it is used within the list of Items. IFC2x3-CHANGE The inverse attribute LayerAssignments has been added. IFC4-CHANGE The inverse attribute LayerAssignment has been restricted to max 1. Upward compatibility for file based exchange is guaranteed.
	StyledByItem	SET [0:1] OF IfcStyledItem FOR Item	Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve. IFC2x3-CHANGE The inverse attribute StyledByItem has been added.
IfcSolidModel (1)
*	Dim	IfcDimensionCount	This attribute is formally derived. `3` The space dimensionality of this class, it is always 3.
IfcManifoldSolidBrep (1)
1	Outer	IfcClosedShell	A closed shell defining the exterior boundary of the solid. The shell normal shall point away from the interior of the solid.
Click to show 4 hidden inherited attributes
IfcAdvancedBrepWithVoids (1)
2	Voids	SET [1:?] OF IfcClosedShell	No description available.

Table 8.8.3.2.A

8.8.3.2.4 Formal propositions

Name Description

VoidsHaveAdvancedFaces

Each face of the voids within the advanced B-rep with voids shall be of type IfcAdvancedFace.

 SIZEOF (QUERY (Vsh <* Voids |
  SIZEOF (QUERY (Afs <* Vsh.CfsFaces |
  (NOT ('IFC4X3_DEV_738df036.IFCADVANCEDFACE' IN TYPEOF(Afs)))
  )) = 0
)) = 0

Table 8.8.3.2.B

8.8.3.2.5 Formal representation

 ENTITY IfcAdvancedBrepWithVoids
 SUBTYPE OF (IfcAdvancedBrep);
	Voids : SET [1:?] OF IfcClosedShell;
 WHERE
	VoidsHaveAdvancedFaces : SIZEOF (QUERY (Vsh <* Voids |
  SIZEOF (QUERY (Afs <* Vsh.CfsFaces |
  (NOT ('IFC4X3_DEV_738df036.IFCADVANCEDFACE' IN TYPEOF(Afs)))
  )) = 0
)) = 0;
END_ENTITY;

8.8.3.2.6 References

IfcAdvancedBrep