added |

*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 | Type | Description |
---|---|---|---|

IfcRepresentationItem | |||

LayerAssignment | SET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItems | 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. | |

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. | |

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. |

2 | Position | OPTIONAL 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. |

IfcRevolvedAreaSolid | |||

3 | Axis | IfcAxis1Placement | Axis about which revolution will take place. |

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. |

AxisLine | INVALID | The line of the axis of revolution. | |

IfcRevolvedAreaSolidTapered | |||

5 | EndSweptArea | IfcProfileDef |

ENTITY IfcRevolvedAreaSolidTapered SUBTYPE OF (IfcRevolvedAreaSolid); EndSweptArea : IfcProfileDef; WHERE CorrectProfileAssignment : IfcTaperedSweptAreaProfiles(SELF\IfcSweptAreaSolid.SweptArea, SELF.EndSweptArea); END_ENTITY;