IfcLightSource

Natural language names
deLichtquelle
enLight Source
frSource de lumière
Semantic definitions at the entity
Entity definition
NOTE  Definition according to ISO 10303-46:
The light source entity is determined by the reflectance specified in the surface style rendering. Lighting is applied on a surface by surface basis: no interactions between surfaces such as shadows or reflections are defined.
NOTE  Entity adapted from light_source defined in ISO 10303-46.
NOTE  In addition to the attributes as defined in ISO10303-46 the following additional properties from ISO/IEC 14772-1:1997 (VRML) are added: ambientIntensity and Intensity. The attribute Name has been added as well (as it is not inherited via representation_item).
HISTORY  New entity in IFC2x, renamed and enhanced in IFC2x2.
Attribute definitions
#AttributeTypeCardinalityDescription C
1NameIfcLabel[0:1] The name given to the light source in presentation. X
2LightColourIfcColourRgb[1:1] Definition from ISO/CD 10303-46:1992: Based on the current lighting model, the colour of the light to be used for shading. Definition from VRML97 - ISO/IEC 14772-1:1997: The color field specifies the spectral color properties of both the direct and ambient light emission as an RGB value. X
3AmbientIntensityIfcNormalisedRatioMeasure[0:1] Definition from VRML97 - ISO/IEC 14772-1:1997: The ambientIntensity specifies the intensity of the ambient emission from the light. Light intensity may range from 0.0 (no light emission) to 1.0 (full intensity). X
4IntensityIfcNormalisedRatioMeasure[0:1] Definition from VRML97 - ISO/IEC 14772-1:1997: The intensity field specifies the brightness of the direct emission from the ligth. Light intensity may range from 0.0 (no light emission) to 1.0 (full intensity). X
Inherited definitions from supertypes
Entity inheritance IfcLightSourceAmbient IfcLightSourceDirectional IfcLightSourceGoniometric IfcLightSourcePositional IfcGeometricRepresentationItem IfcRepresentationItem
Attribute inheritance
#AttributeTypeCardinalityDescriptionC
IfcRepresentationItem
LayerAssignmentIfcPresentationLayerAssignment
@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
StyledByItemIfcStyledItem
@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
IfcLightSource
1NameIfcLabel[0:1] The name given to the light source in presentation. X
2LightColourIfcColourRgb[1:1] Definition from ISO/CD 10303-46:1992: Based on the current lighting model, the colour of the light to be used for shading. Definition from VRML97 - ISO/IEC 14772-1:1997: The color field specifies the spectral color properties of both the direct and ambient light emission as an RGB value. X
3AmbientIntensityIfcNormalisedRatioMeasure[0:1] Definition from VRML97 - ISO/IEC 14772-1:1997: The ambientIntensity specifies the intensity of the ambient emission from the light. Light intensity may range from 0.0 (no light emission) to 1.0 (full intensity). X
4IntensityIfcNormalisedRatioMeasure[0:1] Definition from VRML97 - ISO/IEC 14772-1:1997: The intensity field specifies the brightness of the direct emission from the ligth. Light intensity may range from 0.0 (no light emission) to 1.0 (full intensity). X
Formal representations
XSD Specification
 <xs:element name="IfcLightSource" type="ifc:IfcLightSource" abstract="true" substitutionGroup="ifc:IfcGeometricRepresentationItem" nillable="true"/>
 <xs:complexType name="IfcLightSource" abstract="true">
  <xs:complexContent>
   <xs:extension base="ifc:IfcGeometricRepresentationItem">
    <xs:sequence>
     <xs:element name="LightColour" type="ifc:IfcColourRgb" nillable="true"/>
    </xs:sequence>
    <xs:attribute name="Name" type="ifc:IfcLabel" use="optional"/>
    <xs:attribute name="AmbientIntensity" type="ifc:IfcNormalisedRatioMeasure" use="optional"/>
    <xs:attribute name="Intensity" type="ifc:IfcNormalisedRatioMeasure" use="optional"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
EXPRESS Specification
ENTITY IfcLightSource
 ABSTRACT SUPERTYPE OF(ONEOF(IfcLightSourceAmbient, IfcLightSourceDirectional, IfcLightSourceGoniometric, IfcLightSourcePositional))
 SUBTYPE OF (IfcGeometricRepresentationItem);
  Name : OPTIONAL IfcLabel;
  LightColour : IfcColourRgb;
  AmbientIntensity : OPTIONAL IfcNormalisedRatioMeasure;
  Intensity : OPTIONAL IfcNormalisedRatioMeasure;
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

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