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.
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.
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.
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
IfcGrid with u-axes, v-axes, and optionally w-axes
that cannot be described by the patterns RECTANGULAR, RADIAL,
NOTE Grids with irregular offsets between parallel
or cocentric grid axes are not considered as IRREGULAR
if they otherwise meet the criteria of RECTANGULAR,
any other grid not conforming to any of the above
not known whether grid conforms to any standard type.
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.
XSD Specification: <xs:simpleType name="IfcGridTypeEnum">
TYPE IfcGridTypeEnum = ENUMERATION OF (
Link to this page