IfcGridTypeEnum

Item	SPF	XML	Change	Description
IFC2x3 to IFC4
IfcGridTypeEnum			ADDED

Semantic definitions at the type

Type definition

This enumeration defines the different layout types of grids. Restriction on the correct use of IfcGrid instantiations may be imposed depending on the value of the PredefinedType being IfcGridTypeEnum.

HISTORY New enumeration in IFC4.

NOTE View definitions or implementer agreements may impose further restrictions on how to populate the grid axes. The first grid axis being part of u-axes may have to be parallel to the x-axis of the grid object placement.

Enumeration definition

Constant	Description
RECTANGULAR	An IfcGrid with straight u-axes and straight v-axes being perpendicular to each other. All grid axes being part of u-axes can be described by one axis line and all other axes being 2D offsets from this axis line. The same applies to all grid axes being part of V-axes.
RADIAL	An IfcGrid with straight u-axes and curved v-axes. All grid axes being part of V-axes have the same center point and are concentric circular arcs. All grid axes being part of u-axes intersect at the same center point and rotate counter clockwise.
TRIANGULAR	An IfcGrid with u-axes, v-axes, and w-axes all being co-linear axis lines with a 2D offset. The v-axes are at 60 degree rotated counter clockwise from the u-axes, and the w-axes are at 120 degree rotated counter clockwise from the u-axes.
IRREGULAR	An IfcGrid with u-axes, v-axes, and optionally w-axes that cannot be described by the patterns.
USERDEFINED	Any other grid not conforming to any of the above restrictions.
NOTDEFINED	Not known whether grid conforms to any standard type.

Formal representations

XML Specification

 <xs:simpleType name="IfcGridTypeEnum">

  <xs:restriction base="xs:string">

   <xs:enumeration value="rectangular"/>

   <xs:enumeration value="radial"/>

   <xs:enumeration value="triangular"/>

   <xs:enumeration value="irregular"/>

   <xs:enumeration value="userdefined"/>

   <xs:enumeration value="notdefined"/>

  </xs:restriction>

 </xs:simpleType>

EXPRESS Specification


TYPE IfcGridTypeEnum = ENUMERATION OF (

 RECTANGULAR, 
 RADIAL, 
 TRIANGULAR, 
 IRREGULAR, 
 USERDEFINED, 
 NOTDEFINED);
END_TYPE;


 EXPRESS-G diagram

	Grid Type Enum
	Enumération des types de grille