该页全部中文内容仅供20252453-T-424 项目组内部使用

20252453-T-424 项目

4.1.7.1.7 CoG几何体(CoG Geometry)

元素可能具有描述重心(Center of Gravity)的“CoG”表示形式,该表示形式为一个点。此表示形式可用于允许验证检查,以在考虑可接受的数值容差的情况下,验证导入的“Body”形状表示后的重心是否与导出时创建的显式值匹配。

“CoG”表示形式的表示标识符、类型以及唯一允许的单个表示项为:

下图展示了应用此概念时使用的通用类和关系。 此外,概念可能对常见或标准化的行业实践和场景具有特殊意义。对于这些特定的使用场景,下表展示了用户可采用的推荐通用使用模式列表。

<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProduct.htm'>IfcProduct</a> IfcProduct 1. GlobalId [1:1] 2. OwnerHistory [0:1] 3. Name [0:1] 4. Description [0:1]      HasAssignments [0:?]      Nests [0:1]      IsNestedBy [0:?]      HasContext [0:1]      IsDecomposedBy [0:?]      Decomposes [0:1]      HasAssociations [0:?] 5. ObjectType [0:1]      IsDeclaredBy [0:1]      Declares [0:?]      IsTypedBy [0:1]      IsDefinedBy [0:?] 6. ObjectPlacement [0:1] 7. Representation [0:1]      ReferencedBy [0:?]      PositionedRelativeTo [0:?]      ReferencedInStructures [0:?] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProductDefinitionShape.htm'>IfcProductDefinitionShape</a> IfcProductDefinitionShape 1. Name [0:1] 2. Description [0:1] 3. Representations [1:?]      ShapeOfProduct [1:?]      HasShapeAspects [0:?] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProduct.htm'>IfcProduct</a>:Representation1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProductDefinitionShape.htm'>IfcProductDefinitionShape</a>:IfcProductDefinitionShape0 <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a> IfcShapeRepresentation 1. ContextOfItems [1:1] Identifier 2. RepresentationIdentifier [0:1] Type 3. RepresentationType [0:1] 4. Items [1:?]      RepresentationMap [0:1]      LayerAssignments [0:?]      OfProductRepresentation [0:?]      OfShapeAspect [0:1] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProductDefinitionShape.htm'>IfcProductDefinitionShape</a>:Representations1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:IfcShapeRepresentation0 <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcGeometricRepresentationContext.htm'>IfcGeometricRepresentationContext</a> IfcGeometricRepresentationContext 1. ContextIdentifier [0:1] 2. ContextType [0:1]      RepresentationsInContext [0:?] 3. CoordinateSpaceDimension [1:1] 4. Precision [0:1] 5. WorldCoordinateSystem [1:1] 6. TrueNorth [0:1]      HasSubContexts [0:?]      HasCoordinateOperation [0:1] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:ContextOfItems1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcGeometricRepresentationContext.htm'>IfcGeometricRepresentationContext</a>:IfcGeometricRepresentationContext0 IfcLabel_0 IfcLabel <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:RepresentationIdentifier1->IfcLabel_0:IfcLabel0 IfcLabel_1 IfcLabel <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:RepresentationType1->IfcLabel_1:IfcLabel0 <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcCartesianPoint.htm'>IfcCartesianPoint</a> IfcCartesianPoint      LayerAssignment [0:1]      StyledByItem [0:1] 1. Coordinates [1:3] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:Items1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcCartesianPoint.htm'>IfcCartesianPoint</a>:IfcCartesianPoint0 constraint_0 =CoG IfcLabel_0->constraint_0
Figure 4.1.7.1.7.A

General Usage

ApplicableEntity
IfcProduct
表 4.1.7.1.7.B