188.8.131.52.1 Semantic definition
The IfcCurveBoundedSurface is a parametric surface with boundaries defined by p-curves, that is, a curve which lies on the basis of a surface and is defined in the parameter space of that surface. The p-curve is a special type of a composite curve segment and shall only be used to bound a surface.
The outer boundary shall be either defined by:
- an IfcOuterBoundaryCurve a closed composite curve on surface for the definition of an outer boundary, in this case the attribute ImplicitOuter has to be set to FALSE, or
- an implicit boundary of the bounded surface, e.g. the u1, u2, v1, v2 of IfcRectangularTrimmedSurface, in this case the attribute ImplicitOuter has to be set to TRUE.
- Each curve in the set of Boundaries shall be closed.
- No two curves in the set of Boundaries shall intersect.
- At most one of the boundary curves may enclose any other boundary curve. If an IfcOuterBoundaryCurve is designated, only that curve may enclose any other boundary curve.
184.108.40.206.2 Entity inheritance
|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.
This attribute is formally derived.
The space dimensionality of IfcSurface. It is always a three-dimensional geometric representation item.
|Click to show 3 hidden inherited attributes Click to hide 3 inherited attributes|
The surface to be bounded.
|2||Boundaries||SET [1:?] OF IfcBoundaryCurve||
The outer boundary of the surface.
No description available.
220.127.116.11.4 Formal representation
ENTITY IfcCurveBoundedSurface SUBTYPE OF (IfcBoundedSurface); BasisSurface : IfcSurface; Boundaries : SET [1:?] OF IfcBoundaryCurve; ImplicitOuter : IfcBoolean; END_ENTITY;