IfcSweptAreaSolid

IfcSweptAreaSolid通过扫描表示方案来表示三维形状，允许二维平面横截面扫过空间。
扫描区域由横截面定义，由IfcProfileDef子类型表示，该子类型是隐式平面上的闭合二维边界。扫描区域在对象坐标系的xy平面中定义。扫描操作应用于IfcSweptAreaSolid子类型中定义的扫描区域，某些子类型需要将扫描区域隐式转换为扫描的起始位置。
可选的位置坐标系允许相对于对象坐标系重新定位生成的扫描实体。
注：定义根据ISO/CD 10303-42:1992
扫描区域实体实体收集由平面有界曲面上的扫掠动作按程序定义的实体。扫描实体的位置即空间取决于扫描区域的位置。扫描区域将是生成的扫描区域实体的一个面，但角度等于2π（或360度）的旋转区域实体除外。
注：实体改编自ISO 10303-42中定义的扫掠面实体。
IFC1.5中增加的新实体
IFC4 CHANGE属性位置已更改为可选，具有对基于文件的交换的向上兼容性。

Formal Propositions

Rule	Description
SweptAreaType	The profile definition for the swept area solid shall be of type AREA.

 

 

 

 

#	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
IfcSolidModel
	Dim :=3	IfcDimensionCount	[1:1]	The space dimensionality of this class, it is always 3.	X
IfcSweptAreaSolid
1	SweptArea	IfcProfileDef	[1:1]	The surface defining the area to be swept. It is given as a profile definition within the xy plane of the position coordinate system.	X
2	Position	IfcAxis2Placement3D	[0:1]	Position coordinate system for the resulting swept solid of the sweeping operation. The position coordinate system allows for re-positioning of the swept solid. If not provided, the swept solid remains within the position as determined by the cross section or by the directrix used for the sweeping operation.	X

EXPRESS Specification

ENTITY IfcSweptAreaSolid
 ABSTRACT SUPERTYPE OF(ONEOF(IfcExtrudedAreaSolid, IfcFixedReferenceSweptAreaSolid, IfcRevolvedAreaSolid, IfcSurfaceCurveSweptAreaSolid))
 SUBTYPE OF (IfcSolidModel);
  SweptArea : IfcProfileDef;
  Position : OPTIONAL IfcAxis2Placement3D;
 WHERE
  SweptAreaType : SweptArea.ProfileType = IfcProfileTypeEnum.Area;
END_ENTITY;