8.14.3.10 IfcPresentationLayerWithStyle

Assignation de calque avec style
Zuordnung zu Präsentations-Layer mit Stilvorgaben

An IfcPresentationLayerAssignmentWithStyle extends the presentation layer assignment with capabilities to define visibility control, access control and common style information.

The visibility control allows to define a layer to be either 'on' or 'off', and/or 'frozen' or 'not frozen'. The access control allows to block graphical entities from manipulations by setting a layer to be either 'blocked' or 'not blocked'. Common style information can be given to the layer.

NOTE  Style information assigned to layers is often restricted to 'layer colour', 'curve font', and/or 'curve width'. These styles are assigned by using the IfcCurveStyle within the LayerStyles.
NOTE  If a styled item is assigned to a layer using the IfcPresentationLayerAssignmentWithStyle, it inherits the style information from the layer. In this case, it should omit its own style information. If the styled item has style information assigned (such as by IfcCurveStyle, IfcFillAreaStyle, IfcTextStyle, IfcSurfaceStyle, IfcSymbolStyle), then it overrides the style provided by the IfcPresentationLayerAssignmentWithStyle.
NOTE  The IfcPresentationLayerAssignmentWithStyle extends the presentation_layer_assignment entity as defined in ISO/IS 10303-46:1994, p. 36.
HISTORY  New entity in IFC2x2.
IFC2x3 CHANGE  The attributes have been modified without upward compatibility.

XSD Specification:

 <xs:element name="IfcPresentationLayerWithStyle" type="ifc:IfcPresentationLayerWithStyle" substitutionGroup="ifc:IfcPresentationLayerAssignment" nillable="true"/>
 <xs:complexType name="IfcPresentationLayerWithStyle">
  <xs:complexContent>
   <xs:extension base="ifc:IfcPresentationLayerAssignment">
    <xs:sequence>
     <xs:element name="LayerStyles">
      <xs:complexType>
       <xs:sequence>
        <xs:element ref="ifc:IfcPresentationStyle" minOccurs="0" maxOccurs="unbounded"/>
       </xs:sequence>
       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcPresentationStyle"/>
       <xs:attribute ref="ifc:cType" fixed="set"/>
       <xs:attribute ref="ifc:arraySize" use="optional"/>
      </xs:complexType>
     </xs:element>
    </xs:sequence>
    <xs:attribute name="LayerOn" type="ifc:logical" use="optional"/>
    <xs:attribute name="LayerFrozen" type="ifc:logical" use="optional"/>
    <xs:attribute name="LayerBlocked" type="ifc:logical" use="optional"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>

EXPRESS Specification:

ENTITY IfcPresentationLayerWithStyle
SUBTYPE OF IfcPresentationLayerAssignment;
LayerOn : LOGICAL;
LayerFrozen : LOGICAL;
LayerBlocked : LOGICAL;
LayerStyles : SET OF IfcPresentationStyle;
WHERE
ApplicableOnlyToItems : SIZEOF(QUERY(temp <* AssignedItems | ( SIZEOF(TYPEOF(temp) * [ 'IFCGEOMETRYRESOURCE.IFCGEOMETRICREPRESENTATIONITEM', 'IFCGEOMETRYRESOURCE.IFCMAPPEDITEM']) = 1) )) = SIZEOF(AssignedItems);
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

Attribute Definitions:

LayerOn : A logical setting, TRUE indicates that the layer is set to 'On', FALSE that the layer is set to 'Off', UNKNOWN that such information is not available.
LayerFrozen : A logical setting, TRUE indicates that the layer is set to 'Frozen', FALSE that the layer is set to 'Not frozen', UNKNOWN that such information is not available.
LayerBlocked : A logical setting, TRUE indicates that the layer is set to 'Blocked', FALSE that the layer is set to 'Not blocked', UNKNOWN that such information is not available.
LayerStyles : Assignment of presentation styles to the layer to provide a default style for representation items.
NOTE  In most cases the assignment of styles to a layer is restricted to an IfcCurveStyle representing the layer curve colour, layer curve thickness, and layer curve type.
IFC4 CHANGE  The data type has been changed from IfcPresentationStyleSelect (now deprecated) to IfcPresentationStyle.

Formal Propositions:

ApplicableOnlyToItems : The IfcPresentationLayerWithStyle shall only be used to assign subtypes of IfcGeometricRepresentationItem's and to IfcMappedItem. There shall be no instance of subtypes of IfcRepresentation in the set of AssignedItem's.
IFC4 CHANGE  New where rule.

Inheritance Graph:

ENTITY IfcPresentationLayerWithStyle
ENTITY IfcPresentationLayerAssignment
Name : IfcLabel;
Description : OPTIONAL IfcText;
AssignedItems : SET [1:?] OF IfcLayeredItem;
Identifier : OPTIONAL IfcIdentifier;
ENTITY IfcPresentationLayerWithStyle
LayerOn : LOGICAL;
LayerFrozen : LOGICAL;
LayerBlocked : LOGICAL;
LayerStyles : SET OF IfcPresentationStyle;
END_ENTITY;

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