IfcRevolvedAreaSolidTapered

Item	SPF	XML	Change	Description
IFC2x3 to IFC4
IfcRevolvedAreaSolidTapered			ADDED

Semantic definitions at the entity

Entity definition

IfcRevolvedAreaSolidTapered is defined by revolving a cross section along a circular arc. The cross section may change along the revolving sweep from the shape of the start cross section into the shape of the end cross section. Corresponding vertices of the start and end cross sections are then connected. The bounded surface may have holes which will sweep into holes in the solid.

The rotation axis is defined by:

Start point: SELF\IfcSweptAreaSolid.Position.Location
Direction: SELF\IfcRevolvedAreaSolid.Axis
Rotation axis: SELF\IfcRevolvedAreaSolid.AxisLine, created from start point and direction by appying a 1 unit magnitude.
Orientation: Positive angles are applied clockwise when looking into the positive direction of the rotation axis.

The start cross section is defined by SELF\IfcSweptAreaSolid.SweptArea:

A bounded planar surface lying in the XY plane of the position coordinate system defined by SELF\IfcSweptAreaSolid.Position.P[1] and SELF\IfcSweptAreaSolid.Position.P[2]
The rotation axis lies in the plane of the start cross section but shall not intersect the interior of the start cross section.

The end cross section is defined by EndSweptArea:

A bounded planar surface lying in the XY plane of the position coordinate system defined by rotating the start position coordinates provided by SELF\IfcSweptAreaSolid.Position around the rotation axis by the angle given by SELF\IfcRevolvedAreaSolid.Angle.
- The end cross section is topologically similar to the start cross section (having the same number of vertices and edges).
- The end cross section can either be defined by the same paramteric profile using different parameter values, or by a 2D Cartesian transformation of the start profile within the end cross section plane.

The solid is generated by transforming the start cross section into to end cross section. A start face, an end face (each defined by start and end cross sections), and one or more lateral faces. Each lateral face is a ruled surface defined by a pair of corresponding edges of the start and end section. The ruled surfaces are constructed in the cylindrical coordinate space defined by the supertype IfcRevolvedAreaSolid.

HISTORY New entity in IFC4.

Informal Propositions:

Mirroring within IfcDerivedProfileDef.Operator shall not be used

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
5	EndSweptArea	IfcProfileDef			X

Formal Propositions

Rule	Description
CorrectProfileAssignment	The SweptArea as start profile and the EndSweptArea as end profile shall be compatible.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
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. 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.	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. IFC2x3 CHANGE The inverse attribute StyledByItem has been added.	X
IfcGeometricRepresentationItem
IfcSolidModel
	Dim :=3	IfcDimensionCount		The space dimensionality of this class, it is always 3.	X
IfcSweptAreaSolid
1	SweptArea	IfcProfileDef		The surface defining the area to be swept. It is given as a profile definition within the xy plane of the position coordinate system.	X
2	Position	IfcAxis2Placement3D	?	Position coordinate system for the resulting swept solid of the sweeping operation. The position coordinate system allows for re-positioning of the swept solid. If not provided, the swept solid remains within the position as determined by the cross section or by the directrix used for the sweeping operation. IFC4 CHANGE The attribute has been changed to OPTIONAL with upward compatibility for file-based exchange.	X
IfcRevolvedAreaSolid
3	Axis	IfcAxis1Placement		Axis about which revolution will take place.	X
4	Angle	IfcPlaneAngleMeasure		The angle through which the sweep will be made. This angle is measured from the plane of the swept area provided by the XY plane of the position coordinate system.	X
	AxisLine :=IfcRepresentationItem() \|\| IfcGeometricRepresentationItem () \|\| IfcCurve() \|\| IfcLine(Axis.Location, IfcRepresentationItem() \|\| IfcGeometricRepresentationItem () \|\| IfcVector(Axis.Z,1.0))	IfcLine		The line of the axis of revolution.	X
IfcRevolvedAreaSolidTapered
5	EndSweptArea	IfcProfileDef			X

Formal representations

XML Specification

 <xs:element name="IfcRevolvedAreaSolidTapered" type="ifc:IfcRevolvedAreaSolidTapered" substitutionGroup="ifc:IfcRevolvedAreaSolid" nillable="true"/>

 <xs:complexType name="IfcRevolvedAreaSolidTapered">

  <xs:complexContent>

   <xs:extension base="ifc:IfcRevolvedAreaSolid">

    <xs:sequence>

     <xs:element name="EndSweptArea" type="ifc:IfcProfileDef" nillable="true"/>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcRevolvedAreaSolidTapered

 SUBTYPE OF (IfcRevolvedAreaSolid);

  EndSweptArea : IfcProfileDef;

 WHERE

  CorrectProfileAssignment : IfcTaperedSweptAreaProfiles(SELF\IfcSweptAreaSolid.SweptArea, SELF.EndSweptArea);
END_ENTITY;

 EXPRESS-G diagram

	Sich verjüngender Festkörper - durch Rotation
	Revolved Area Solid Tapered