IFC 4.3.1.0 (IFC4X3_ADD1)

8.9.3.68 IfcSurface

ABSTRACT This definition may not be instantiated

8.9.3.68.1 Semantic definition

An IfcSurface is a 2-dimensional representation item positioned in 3-dimensional space. 2-dimensional means that each point at the surface can be defined by a 2-dimensional coordinate system, usually by u and v coordinates.

Informal Propositions:

  1. A surface has non zero area.
  2. A surface is arcwise connected.

8.9.3.68.2 Entity inheritance

8.9.3.68.3 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.

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.

Click to show 2 hidden inherited attributes Click to hide 2 inherited attributes
IfcSurface (1)
* Dim IfcDimensionCount

This attribute is formally derived.

3

The space dimensionality of IfcSurface. It is always a three-dimensional geometric representation item.

Table 8.9.3.68.A

8.9.3.68.4 Formal representation

ENTITY IfcSurface
 ABSTRACT SUPERTYPE OF (ONEOF
	(IfcBoundedSurface
	,IfcElementarySurface
	,IfcSectionedSurface
	,IfcSweptSurface))
 SUBTYPE OF (IfcGeometricRepresentationItem);
 DERIVE
	 Dim : IfcDimensionCount := 3;
END_ENTITY;

8.9.3.68.5 References