IfcShell
Definition from ISO/CD 10303-42:1992 This type collects together,
for reference when constructing more complex models, the subtypes which have
the characteristics of a shell. A shell is a connected object of fixed
dimensionality d = 0; 1; or 2, typically used to bound a region. The domain of
a shell, if present, includes its bounds and 0 £ X < ¥ .
- A shell of dimensionality 0 is represented by a graph consisting of a
single vertex. The vertex shall not have any associated edges.
- A shell of dimensionality 1 is represented by a connected graph of
dimensionality 1.
- A shell of dimensionality 2 is a topological entity constructed by
joining faces along edges. Its domain, if present, is a connected, orientable
2-manifold with boundary, that is, a connected, oriented, finite,
non-self-intersecting surface, which may be closed or open.
Definition from IAI: Shells of dimensionality 0 and 1 are not
part of the current IFC release.
NOTE Corresponding STEP type:
shell. Please refer to ISO/IS 10303-42:1994, p. 127 for the final definition of
the formal standard. Only the select items closed_shell (IfcClosedShell) and
open_shell (IfcOpenShell) have been incorporated in the current IFC
release.
HISTORY: New type in IFC
Release 2x
ISSUE: See issue and change log for changes made in IFC Release
2x
EXPRESS specification: