ifcarbitraryprofiledeffithvoids定义了一个带有孔的任意闭合二维轮廓。它由外边界和内边界给出。ifcarbitraryprofiledeffithvoids的一个常见用法是用作创建扫掠曲面或扫掠实体的横截面。
IFC2x中增加的的新实体。
非正式提议:
1、外曲线和所有内曲线应为闭合曲线。
2、外曲线应包括所有内曲线。
3、内曲线不得与外曲线或任何其他内曲线相交。也就是说,考虑到几何表示上下文的几何精度因素,轮廓定义的两条曲线不得有共同点或段。换句话说,曲线不能交叉,也不能相互接触。
4、没有内曲线可以封闭另一条内曲线。
下图说明了带有空隙的任意闭合轮廓定义。在超类型IfcArbitraryClosedProfileDef中定义的外圆曲线和内曲线在相同的基础坐标系中定义。公共基础坐标系由使用轮廓定义的扫掠区域实体定义。它是xy平面:
IfcSweptAreaSolid.位置
或者,如果是截面脊椎,则为每个列表成员的xy平面IfcSectionedSpine.CrossSectionPositions(IfcSectionedSpine.CrossSectionPositions横截面位置). OuterCurve属性定义一条二维闭合有界曲线,InnerCurves定义一组二维闭合有界曲线。
Formal Propositions
Rule | Description |
---|---|
WR1 | The type of the profile shall be AREA, as it can only be involved in the definition of a swept area. |
WR2 | All inner curves shall have the dimensionality of 2. |
WR3 | None of the inner curves shall by of type IfcLine, as an IfcLine can not be a closed curve. |
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 | |
IfcArbitraryClosedProfileDef | |||||
3 | OuterCurve | IfcCurve | [1:1] | Bounded curve, defining the outer boundaries of the arbitrary profile. | X |
IfcArbitraryProfileDefWithVoids | |||||
4 | InnerCurves | IfcCurve | S[1:?] | Set of bounded curves, defining the inner boundaries of the arbitrary profile. | X |
Concept inheritance
# | Concept | Model View |
---|---|---|
IfcProfileDef | ||
Property Sets for Objects | Common Use Definitions |
EXPRESS Specification
ENTITY IfcArbitraryProfileDefWithVoids SUBTYPE OF (IfcArbitraryClosedProfileDef); InnerCurves : SET [1:?] OF IfcCurve; WHERE WR1 : SELF\IfcProfileDef.ProfileType = AREA; WR2 : SIZEOF(QUERY(temp <* InnerCurves | temp.Dim <> 2)) = 0; WR3 : SIZEOF(QUERY(temp <* InnerCurves | 'IFCGEOMETRYRESOURCE.IFCLINE' IN TYPEOF(temp))) = 0; END_ENTITY;