IFCCIRCLEPROFILEDEF
实体定义
IFCCIRCEPROFILEDEF将圆定义为扫掠曲面几何图形或扫掠区域实体使用的轮廓定义。它由其“半径”属性给出，并放置在由“位置”属性建立的二维位置坐标系中。
IFC1.5中新实体的历史记录。
图385说明了圆轮廓定义的参数。参数化纵断面定义自己的位置坐标系。基础坐标系由使用轮廓定义的扫描曲面或扫描区域实体定义。它是以下任一项的xy平面：
IfcSweptSurface.位置
IfcSweptAreaSolid.位置
或者，对于截面脊椎，它是IfcSectionedSpine.CrossSectionPositions的每个列表成员的xy平面。通过使用位置位置的偏移，可以将参数化轮廓定位在中心位置（使用x，y偏移=0），或相对于轮廓的任何位置。显式坐标偏移用于定义基点（例如，左上界）。“位置”属性定义圆的二维位置坐标系。
“半径”属性定义圆的半径。
Attribute inheritance
| # | Attribute | Type | Cardinality | Description | C |
|---|---|---|---|---|---|
| IfcProfileDef | |||||
| 1 | ProfileType | IfcProfileTypeEnum | [1:1] | Defines the type of geometry into which this profile definition shall be resolved, either a curve or a surface area. In case of curve the profile should be referenced by a swept surface, in case of area the profile should be referenced by a swept area solid. | X |
| 2 | ProfileName | IfcLabel | [0:1] | Human-readable name of the profile, for example according to a standard profile table. As noted above, machine-readable standardized profile designations should be provided in IfcExternalReference.ItemReference. | X |
| HasExternalReference | IfcExternalReferenceRelationship @RelatedResourceObjects |
S[0:?] | Reference to external information, e.g. library, classification, or document information, which is associated with the profile. | X | |
| HasProperties | IfcProfileProperties @ProfileDefinition |
S[0:?] | Additional properties of the profile, for example mechanical properties. | X | |
| IfcParameterizedProfileDef | |||||
| 3 | Position | IfcAxis2Placement2D | [0:1] | Position coordinate system of the parameterized profile definition. If unspecified, no translation and no rotation is applied. | X |
| IfcCircleProfileDef | |||||
| 4 | Radius | IfcPositiveLengthMeasure | [1:1] | The radius of the circle. | X |
EXPRESS Specification
ENTITY IfcCircleProfileDef
SUPERTYPE OF(IfcCircleHollowProfileDef)
SUBTYPE OF (IfcParameterizedProfileDef);
Radius : IfcPositiveLengthMeasure;
END_ENTITY;
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