IfcShapeModel

 

IfcShapeModel表示表示表示上下文中产品形状或产品组件形状的特定几何和/或拓扑表示的概念。此表示上下文必须是几何表示上下文(除了没有关联几何体的拓扑表示外)。这两个子类型是ifcshaperepression,用于覆盖表示形状的几何模型,以及ifctopology表示,以涵盖产品或产品组件的综合性。拓扑可能具有关联的几何体,也可能没有关联。

IFCSHAPHEModel可以是产品(通过IFCPProductDefinitionShape)的形状表示(几何和/或拓扑),或产品形状(通过IFCSHAPHEASPACT)的形状表示(几何和/或拓扑)。

在IFC2x3中增加的新实体。

 

Formal Propositions

RuleDescription
WR11 The IfcShapeModel shall be used by an IfcProductRepresentation, by an IfcRepresentationMap or by an IfcShapeAspect.
 

 

 

 

 

 

Attribute inheritance

#AttributeTypeCardinalityDescriptionC
IfcRepresentation
1 ContextOfItems IfcRepresentationContext [1:1] Definition of the representation context for which the different subtypes of representation are valid. X
2 RepresentationIdentifier IfcLabel [0:1] The optional identifier of the representation as used within a project. X
3 RepresentationType IfcLabel [0:1] The description of the type of a representation context. The representation type defines the type of geometry or topology used for representing the product representation. More information is given at the subtypes IfcShapeRepresentation and IfcTopologyRepresentation.
The supported values for context type are to be specified by implementers agreements.
X
4 Items IfcRepresentationItem S[1:?] Set of geometric representation items that are defined for this representation. X
  RepresentationMap IfcRepresentationMap
@MappedRepresentation
S[0:1] Use of the representation within an IfcRepresentationMap. If used, this IfcRepresentation may be assigned to many representations as one of its Items using an IfcMappedItem. Using IfcRepresentationMap is the way to share one representation (often of type IfcShapeRepresentation) by many products. X
  LayerAssignments IfcPresentationLayerAssignment
@AssignedItems
S[0:?] Assignment of the whole representation to a single or multiple layer(s). The LayerAssigments can be overridden by LayerAssigments of the IfcRepresentationItem's within the list of Items.
NOTE  Implementation agreements can restrict the maximum number of layer assignments to 1.
X
  OfProductRepresentation IfcProductRepresentation
@Representations
S[0:?] Reference to the product representations to which this individual representation applies. In most cases it is the reference to one or many product shapes, to which this shape representation is applicable. X
IfcShapeModel
  OfShapeAspect IfcShapeAspect
@ShapeRepresentations
S[0:1] Reference to the shape aspect, for which it is the shape representation. X
 

EXPRESS Specification

ENTITY IfcShapeModel
 ABSTRACT SUPERTYPE OF(ONEOF(IfcShapeRepresentation, IfcTopologyRepresentation))
 SUBTYPE OF (IfcRepresentation);
 INVERSE
  OfShapeAspect : SET [0:1] OF IfcShapeAspect FOR ShapeRepresentations;
 WHERE
  WR11 : (SIZEOF(SELF\IfcRepresentation.OfProductRepresentation) = 1) XOR (SIZEOF(SELF\IfcRepresentation.RepresentationMap) = 1) XOR (SIZEOF(OfShapeAspect) = 1);
END_ENTITY;

 

 

 

 

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posted @ 2021-06-10 15:46  西北逍遥  阅读(93)  评论(0编辑  收藏  举报