IfcVertexLoop

Semantic definitions at the entity

Entity definition

NOTE Definition according to ISO/CD 10303-42:1992
A vertex_loop is a loop of zero genus consisting of a single vertex. A vertex can exist independently of a vertex loop. The topological data shall satisfy the following constraint:

NOTE Entity adapted from vertex_loop defined in ISO 10303-42.

HISTORY New entity in IFC2x2.

Informal Propositions:

A vertex loop has zero extent and dimensionality.
The vertex loop has genus 0.

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
1	LoopVertex	IfcVertex		The vertex which defines the entire loop.	X

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
IfcRepresentationItem
	LayerAssignment	IfcPresentationLayerAssignment @AssignedItems	S[0:1]	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.	X
	StyledByItem	IfcStyledItem @Item	S[0:1]	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.	X
IfcTopologicalRepresentationItem
IfcLoop
IfcVertexLoop
1	LoopVertex	IfcVertex		The vertex which defines the entire loop.	X

Formal representations

XML Specification

 <xs:element name="IfcVertexLoop" type="ifc:IfcVertexLoop" substitutionGroup="ifc:IfcLoop" nillable="true"/>

 <xs:complexType name="IfcVertexLoop">

  <xs:complexContent>

   <xs:extension base="ifc:IfcLoop">

    <xs:sequence>

     <xs:element name="LoopVertex" type="ifc:IfcVertex" nillable="true"/>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcVertexLoop

 SUBTYPE OF (IfcLoop);

  LoopVertex : IfcVertex;

END_ENTITY;

 EXPRESS-G diagram

	Vertexschleife - Topologie
	Vertex Loop
	Boucle de points