IFC 4.3.x development

8.8.3.42 IfcSweptDiskSolidPolygonal

Change log

IFC4

added

IFC4X1

modificationswhere_rules DirectrixIsPolyline definitionChanged from ('ifc4.ifcpolyline' in typeof(self\IfcSweptDiskSolid.Directrix)) or (('ifc4.ifcindexedpolycurve' in typeof(self\IfcSweptDiskSolid.Directrix)) and not(exists(self\IfcSweptDiskSolid.Directrix.Segments))) to ('ifc4x1.ifcpolyline' in typeof(self\IfcSweptDiskSolid.Directrix)) or (('ifc4x1.ifcindexedpolycurve' in typeof(self\IfcSweptDiskSolid.Directrix)) and not(exists(self\IfcSweptDiskSolid.Directrix.Segments)))

IFC4X2

modificationswhere_rules DirectrixIsPolyline definitionChanged from ('ifc4x1.ifcpolyline' in typeof(self\IfcSweptDiskSolid.Directrix)) or (('ifc4x1.ifcindexedpolycurve' in typeof(self\IfcSweptDiskSolid.Directrix)) and not(exists(self\IfcSweptDiskSolid.Directrix.Segments))) to ('ifc4x2.ifcpolyline' in typeof(self\IfcSweptDiskSolid.Directrix)) or (('ifc4x2.ifcindexedpolycurve' in typeof(self\IfcSweptDiskSolid.Directrix)) and not(exists(self\IfcSweptDiskSolid.Directrix.Segments)))

IFC4X3_RC3

modificationswhere_rules DirectrixIsPolyline definitionChanged from ('ifc4x2.ifcpolyline' in typeof(self\IfcSweptDiskSolid.Directrix)) or (('ifc4x2.ifcindexedpolycurve' in typeof(self\IfcSweptDiskSolid.Directrix)) and not(exists(self\IfcSweptDiskSolid.Directrix.Segments))) to ('ifc4x3_rc3.ifcpolyline' in typeof(self\IfcSweptDiskSolid.Directrix)) or (('ifc4x3_rc3.ifcindexedpolycurve' in typeof(self\IfcSweptDiskSolid.Directrix)) and not(exists(self\IfcSweptDiskSolid.Directrix.Segments)))

8.8.3.42.1 Semantic definitions at the entity

The IfcSweptDiskSolidPolygonal is a IfcSweptDiskSolid where the Directrix is restricted to be provided by an poly line only. An optional FilletRadius attribute can be asserted, it is then applied as a fillet to all transitions between the segments of the poly line.

NOTE  The geometric item IfcIndexedPolyCurve provides a more compact representation compared with IfcPolyline. Therefore it is the prefered curve representation for the Directrix. The IfcIndexedPolyCurve shall not have Segments defined, resticting it to a poly line only.

HISTORY  New entity in IFC4.

Informal Propositions:

  1. The FilletRadius, if provided, has to be smaller then or equal to the length of the start and end segment of the IfcPolyline, and smaller then or equal to one half of the lenght of the shortest inner segment.

8.8.3.42.1 Attributes

# Attribute Type Description
IfcRepresentationItem
LayerAssignmentSET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItemsAssignment 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.

> IFC2x3 CHANGE  The inverse attribute LayerAssignments has been added.

> IFC4 CHANGE  The inverse attribute LayerAssignment has been restricted to max 1. Upward compatibility for file based exchange is guaranteed.
StyledByItem SET [0:1] OF IfcStyledItem FOR Item Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve.



> IFC2x3 CHANGE  The inverse attribute StyledByItem has been added.
IfcGeometricRepresentationItem
IfcSolidModel
Dim INVALID The space dimensionality of this class, it is always 3.
IfcSweptDiskSolid
1 Directrix IfcCurve The curve used to define the sweeping operation. The solid is generated by sweeping a circular disk along the Directrix.
2 Radius IfcPositiveLengthMeasure The Radius of the circular disk to be swept along the directrix. Denotes the outer radius, if an InnerRadius is applied.
3 InnerRadius OPTIONAL IfcPositiveLengthMeasure This attribute is optional, if present it defines the radius of a circular hole in the centre of the disk.
4 StartParam OPTIONAL IfcParameterValue The parameter value on the Directrix at which the sweeping operation commences. If no value is provided the start of the sweeping operation is at the start of the Directrix.

> IFC4 CHANGE  The attribute has been changed to OPTIONAL with upward compatibility for file-based exchange.
5 EndParam OPTIONAL IfcParameterValue The parameter value on the Directrix at which the sweeping operation ends. If no value is provided the end of the sweeping operation is at the end of the Directrix.

> IFC4 CHANGE  The attribute has been changed to OPTIONAL with upward compatibility for file-based exchange.
IfcSweptDiskSolidPolygonal
6 FilletRadius OPTIONAL IfcPositiveLengthMeasure The fillet that is equally applied to all transitions between the segments of the IfcPolyline, providing the geometric representation for _the Directrix_. If omited, no fillet is applied to the segments.

8.8.3.42.2 Entity inheritance

dot_inheritance IfcSweptDiskSolidPolygonal IfcSweptDiskSolidPolygonal IfcSweptDiskSolid IfcSweptDiskSolid IfcSweptDiskSolidPolygonal->IfcSweptDiskSolid IfcSolidModel IfcSolidModel IfcSweptDiskSolid->IfcSolidModel IfcSolidModel_children 4 more... IfcSolidModel_children->IfcSolidModel IfcGeometricRepresentationItem IfcGeometricRepresentationItem IfcSolidModel->IfcGeometricRepresentationItem IfcGeometricRepresentationItem_children 24 more... IfcGeometricRepresentationItem_children->IfcGeometricRepresentationItem IfcRepresentationItem IfcRepresentationItem IfcGeometricRepresentationItem->IfcRepresentationItem IfcRepresentationItem_children 3 more... IfcRepresentationItem_children->IfcRepresentationItem

8.8.3.42.3 Formal representations

ENTITY IfcSweptDiskSolidPolygonal
 SUBTYPE OF (IfcSweptDiskSolid);
	FilletRadius : OPTIONAL IfcPositiveLengthMeasure;
 WHERE
	CorrectRadii : NOT(EXISTS(FilletRadius)) OR (FilletRadius >= SELF\IfcSweptDiskSolid.Radius);
	DirectrixIsPolyline : ('IFC4X3_DEV.IFCPOLYLINE' IN TYPEOF(SELF\IfcSweptDiskSolid.Directrix)) OR
(('IFC4X3_DEV.IFCINDEXEDPOLYCURVE' IN TYPEOF(SELF\IfcSweptDiskSolid.Directrix)) AND NOT(EXISTS(SELF\IfcSweptDiskSolid.Directrix.Segments)));
END_ENTITY;