IfcStyledItem

IfcStyledItem保存产品的表示样式信息,可以显式地用于IfcGeometricRepresentationItem作为分配给产品的IfcShapeRepresentation的一部分,或者通过将表示信息分配给被指定为产品的其他表示的IfcMaterial。

①如果IfcStyledItem在来自IfcProductDefinitionShape的引用中使用,则应提供一个项目。

②如果IfcStyledItem在来自IfcMaterialDefinitionRepresentation的引用中使用,则不应提供任何项目。


●注:定义根据ISO/CD 10303-46:1992

样式项是在表示中使用的几何表示项的表示样式的赋值。

●注:实体改编自ISO10303-46中定义的样式项。


IFC2x2中增加的新实体。

IFC2x2附录1更改了实体IfcStyledItem已变得非抽象并添加了属性名。

如果c2x3 CHANGE The attribute Item已设为可选,则可保证基于文件的交换的向上兼容性。

IFC4更改子类型IfcAnnotationOccurrence并删除其子类型。对所有实例化使用IfcStyledItem。样式的数据类型已更改为IfcStyleAssignmentSelect


使用定义

下图说明了IfcStyledItem在两个使用示例中的用法:

①作为几何表示项的表示

②作为材质定义的表示


注意,新的IfcStyleAssignmentSelect允许直接赋值样式,例如IfcCurveStyle、IfcSurfaceStyle,而不使用中间的IfcPresentationStyleAssignment

IfcStyledItem

 

 

 

Rule Description
ApplicableItem A styled item cannot be styled by another styled item.
 

 

 

IfcStyledItem

 

 

# 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
IfcStyledItem
1 Item IfcRepresentationItem [0:1] A geometric representation item to which the style is assigned. X
2 Styles IfcStyleAssignmentSelect S[1:?] Representation styles which are assigned, either to an geometric representation item, or to a material definition. X
3 Name IfcLabel [0:1] The word, or group of words, by which the styled item is referred to. X
EXPRESS Specification
ENTITY IfcStyledItem
 SUBTYPE OF (IfcRepresentationItem);
  Item : OPTIONAL IfcRepresentationItem;
  Styles : SET [1:?] OF IfcStyleAssignmentSelect;
  Name : OPTIONAL IfcLabel;
 WHERE
  ApplicableItem : NOT('IFCPRESENTATIONAPPEARANCERESOURCE.IFCSTYLEDITEM' IN TYPEOF(Item));
END_ENTITY;

 

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