Navigation
Navigate Navigate Navigate Navigate Navigate Navigate Navigate Navigate

IfcRevolvedAreaSolid

Definition from IAI: A revolved area solid (IfcRevolvedAreaSolid) is a solid created by revolving a planar bounded surface about an axis. Both, the axis and planar bounded surface shall be in the same plane and the axis shall not intersect the interior of the swept area. If the swept area has inner boundaries, i.e. holes defined, then those holes shall be swept into holes of the solid. The direction of revolution is clockwise when viewed along the axis in the positive direction.

NOTE: The IfcRevolvedAreaSolid now directly defines the revolution of a cross section (also referred to as profile). It thereby combines the functionality of the previous IfcAttDrivenRevolvedSegment entity. In contrary to the previous IfcAttDrivenRevolvedSegment, the additional start angle attribute has been omited. The axis is required to lie in the xy plane of the position coordinate system.

NOTE: Corresponding STEP entity: revolved_area_solid. Please refer to ISO/IS 10303-42:1994, p. 184 for the final definition of the formal standard. The data type of the inherited SweptArea attribute is different, i.e. of type IfcProfileDef. The position attribute has been added to position the cross section used for the revolution.

HISTORY: New entity in IFC Release 1.5, capabilities of this entity have been enhanced in IFC Release 2x.

Informal propositions:

  1. The AxisLine shall lie in the plane of the SweptArea (as defined at supertype IfcSweptAreaSolid).
  2. The AxisLine shall not intersect the interior of the SweptArea (as defined at supertype IfcSweptAreaSolid).
  3. The Angle shall be between 0° and 360°, or 0 and 2p (depending on the unit type for IfcPlaneAngleMeasure).

Illustration:

revolved area solid

Purpose
The revolved area solid defines the revolution of a 2D area (given by a profile definition) by an axis and angle. The result is a solid.

Parameter
The swept area is given by a profile definition. This profile is defined

  • as a 2D bounded curve within the xy plane of the position coordinate system,
  • as a 2D bounded curve with holes within the xy plane of the position coordinate system,
  • or as a 2D primitive, defined within a 2D position coordinate system, that is placed relative to the xy plane of the position coordinate system

EXPRESS specification:

ENTITY IfcRevolvedAreaSolid
SUBTYPE OF ( IfcSweptAreaSolid);
Axis  :  IfcAxis1Placement;
Angle  :  IfcPlaneAngleMeasure;
DERIVE
AxisLine  :  IfcLine :=  IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcCurve() || IfcLine(Axis.Location, 
  IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector(Axis.Z,1.0));
WHERE
WR31  :  Axis.Location.Coordinates[3] = 0.0;
WR32  :  Axis.Z.DirectionRatios[3] = 0.0;
END_ENTITY;

Attribute definitions:

Axis  :  Axis about which revolution will take place.
Angle  :  Angle through which the sweep will be made. This angle is measured from the plane of the sweep.
AxisLine  :  The line of the axis of revolution.

Inheritance graph

ENTITY IfcRevolvedAreaSolid;
ENTITY IfcRepresentationItem;
INVERSE
LayerAssignments  :  SET OF IfcPresentationLayerAssignment FOR AssignedItems;
StyledByItem  :  SET [0:1] OF IfcStyledItem FOR Item;
ENTITY IfcGeometricRepresentationItem;
ENTITY IfcSolidModel;
DERIVE
Dim  :  IfcDimensionCount :=  3;
ENTITY IfcSweptAreaSolid;
SweptArea  :  IfcProfileDef;
Position  :  IfcAxis2Placement3D;
ENTITY IfcRevolvedAreaSolid;
Axis  :  IfcAxis1Placement;
Angle  :  IfcPlaneAngleMeasure;
DERIVE
AxisLine  :  IfcLine :=  IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcCurve() || IfcLine(Axis.Location, 
  IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector(Axis.Z,1.0));
END_ENTITY;