IfcCurveBoundedPlane

IfcCurveBoundedPlane是一个参数化平面曲面，曲面边界由一条或多条边界曲线定义。有界平面定义为从边界上任何点沿nxt方向的基曲面部分，其中N是曲面法线，T是该点的边界曲线切线向量。如此定义的区域应呈弧形连接。

基本面是一个自行建立位置坐标系的IfcPlane表面。位置. 外边界和内边界（如提供）应位于IFC板表面。外边界和内边界曲线应使用基本面参数化提供的u和v值作为其x和y坐标值进行定义。

注：与ISO 10303-42中定义的曲线边界曲面类似的实体。

IFC1.5中增加的新实体

IFC2x 修改属性OuterBoundary和innerBoundary的数据类型已从Ifc2DCompositeCurve更改为超类型IfcCurve。

#	Attribute	Type	Cardinality	Description	C
1	BasisSurface	IfcPlane	[1:1]	The surface to be bound.	X
2	OuterBoundary	IfcCurve	[1:1]	The outer boundary of the surface.	X
3	InnerBoundaries	IfcCurve	S[0:?]	An optional set of inner boundaries. They shall not intersect each other or the outer boundary.	X

 

#	Attribute	Type	Cardinality	Description	C
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.	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.	X
IfcGeometricRepresentationItem
IfcSurface
	Dim :=3	IfcDimensionCount	[1:1]	The space dimensionality of IfcSurface. It is always a three-dimensional geometric representation item.	X
IfcBoundedSurface
IfcCurveBoundedPlane
1	BasisSurface	IfcPlane	[1:1]	The surface to be bound.	X
2	OuterBoundary	IfcCurve	[1:1]	The outer boundary of the surface.	X
3	InnerBoundaries	IfcCurve	S[0:?]	An optional set of inner boundaries. They shall not intersect each other or the outer boundary.	X

 

EXPRESS Specification

ENTITY IfcCurveBoundedPlane
 SUBTYPE OF (IfcBoundedSurface);
  BasisSurface : IfcPlane;
  OuterBoundary : IfcCurve;
  InnerBoundaries : SET OF IfcCurve;
END_ENTITY;