Flächenmodell (basierend auf Hüllen) | |
Shell Based Surface Model |
An IfcShellBasedSurfaceModel represents the shape by a set of open or closed shells. The connected faces within the shell have a dimensionality 2 and are placed in a coordinate space of dimensionality 3.
NOTE Definition according to ISO/CD 10303-42:1992
A shell based surface model is described by a set of open or closed shells of dimensionality 2. The shells shall not intersect except at edges and vertices. In particular, distinct faces may not intersect. A complete face of one shell may be shared with another shell. Coincident portions of shells shall both reference the same faces, edges and vertices defining the coincident region. There shall be at least one shell. A shell may exist independently of a surface model.
NOTE Entity adapted from shell_based_surface_model defined in ISO 10303-42.
HISTORY New entity in IFC2x.
Informal Propositions:
# | Attribute | Type | Cardinality | Description | C |
---|---|---|---|---|---|
1 | SbsmBoundary | IfcShell | S[1:?] | X | |
Dim :=3 | IfcDimensionCount | [1:1] | The space dimensionality of this class, it is always 3. | X |
# | Attribute | Type | Cardinality | Description | C |
---|---|---|---|---|---|
IfcRepresentationItem | |||||
LayerAssignment | IfcPresentationLayerAssignment @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 | |
StyledByItem | IfcStyledItem @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 | |||||
IfcShellBasedSurfaceModel | |||||
1 | SbsmBoundary | IfcShell | S[1:?] | X | |
Dim :=3 | IfcDimensionCount | [1:1] | The space dimensionality of this class, it is always 3. | X |
<xs:element name="IfcShellBasedSurfaceModel" type="ifc:IfcShellBasedSurfaceModel" substitutionGroup="ifc:IfcGeometricRepresentationItem" nillable="true"/>
<xs:complexType name="IfcShellBasedSurfaceModel">
<xs:complexContent>
<xs:extension base="ifc:IfcGeometricRepresentationItem">
<xs:sequence>
<xs:element name="SbsmBoundary">
<xs:complexType>
<xs:group ref="ifc:IfcShell" maxOccurs="unbounded"/>
<xs:attribute ref="ifc:itemType" fixed="ifc:IfcShell"/>
<xs:attribute ref="ifc:cType" fixed="set"/>
<xs:attribute ref="ifc:arraySize" use="optional"/>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
ENTITY IfcShellBasedSurfaceModel
SUBTYPE OF (IfcGeometricRepresentationItem);
SbsmBoundary : SET [1:?] OF IfcShell;
DERIVE
Dim : IfcDimensionCount := 3;
END_ENTITY;