Kreis | |
Circle | |
Cercle |
An IfcCircle is a curve consisting of a set of points having equal distance from the center.
NOTE A circular arc segment is defined by using the IfcTrimmedCurve with BasisCurve being an IfcCircle.
Figure 340 illustrates the definition of IfcCircle within a three-dimensional position coordinate system placed within the object coordinate system of an element.
Figure 340 — Circle layout |
NOTE Definition according to ISO/CD 10303-42:1992
A circle is defined by a radius and the location and orientation of the circle. Interpretation of data should be as follows:C = SELF\IfcConic.Position.Location
x = SELF\IfcConic.Position.P[1]
y = SELF\IfcConic.Position.P[2]
z = SELF\IfcConic.Position.P[3]
R = Radiusand the circle is parameterized as
The parameterization range is 0 ≤ u ≤ 2π (0 ≤ u ≤ 360 degree).
In the placement coordinate system defined above, the circle is the equation C = 0, whereThe positive sense of the circle at any point is in the tangent direction, T, to the curve at the point, where
NOTE Entity adapted from circle defined in ISO 10303-42
HISTORY New entity in IFC1.0
# | Attribute | Type | Cardinality | Description | C |
---|---|---|---|---|---|
2 | Radius | IfcPositiveLengthMeasure | [1:1] | The radius of the circle, which shall be greater than zero. | 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 | |||||
IfcCurve | |||||
Dim :=IfcCurveDim(SELF) | IfcDimensionCount | [1:1] | The space dimensionality of this abstract class, defined differently for all subtypes, i.e. for IfcLine, IfcConic and IfcBoundedCurve. | X | |
IfcConic | |||||
1 | Position | IfcAxis2Placement | [1:1] | The location and orientation of the conic. Further details of the interpretation of this attribute are given for the individual subtypes." | X |
IfcCircle | |||||
2 | Radius | IfcPositiveLengthMeasure | [1:1] | The radius of the circle, which shall be greater than zero. | X |
<xs:element name="IfcCircle" type="ifc:IfcCircle" substitutionGroup="ifc:IfcConic" nillable="true"/>
<xs:complexType name="IfcCircle">
<xs:complexContent>
<xs:extension base="ifc:IfcConic">
<xs:attribute name="Radius" type="ifc:IfcPositiveLengthMeasure" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
ENTITY IfcCircle
SUBTYPE OF (IfcConic);
Radius : IfcPositiveLengthMeasure;
END_ENTITY;