![]()  | Surface Side | 
IfcSurfaceSide is a denotion of whether negative, positive or both sides of a surface are being referenced.
NOTE Type adapted from surface_side defined in ISO10303-46.
HISTORY New enumeration type in IFC2.0
| Constant | Description | 
|---|---|
| POSITIVE | The side of a surface which is in the same direction as the surface normal derived from the mathematical definition. | 
| NEGATIVE | The side of a surface which is in the opposite direction than the surface normal derived from the mathematical definition. | 
| BOTH | Both, positive and negative side. | 
 <xs:simpleType name="IfcSurfaceSide">
  <xs:restriction base="xs:string">
   <xs:enumeration value="positive"/>
   <xs:enumeration value="negative"/>
   <xs:enumeration value="both"/>
  </xs:restriction>
 </xs:simpleType>
TYPE IfcSurfaceSide = ENUMERATION OF (
 POSITIVE, 
 NEGATIVE, 
 BOTH);
END_TYPE;
  References: IfcSurfaceStyle