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8.9.2.4 IfcBSplineSurfaceForm

8.9.2.4.1 Semantic definition

The IfcBSplineSurfaceForm represents a part of a surface of some specific form.

{ .extDef}

8.9.2.4.2 Type values

Type Description
CONICAL_SURF

A bounded portion of the surface of a right circular cone.

CYLINDRICAL_SURF

A bounded portion of a cylindrical surface.

GENERALISED_CONE

A special case of a ruled surface in which the second curve degenerates to a single point; when represented by a B-spline surface all the control points along one edge will be coincident.

PLANE_SURF

A bounded portion of a plane represented by a B-spline surface of degree 1 in each parameter.

QUADRIC_SURF

A bounded portion of one of the class of surfaces of degree 2 in the variables x, y and z.

RULED_SURF

A surface constructed from two parametric curves by joining with straight lines corresponding points with the same parameter value on each of the curves.

SPHERICAL_SURF

A bounded portion of a sphere, or a complete sphere, represented by a B-spline surface.

SURF_OF_LINEAR_EXTRUSION

A bounded portion of a surface of linear extrusion represented by a B-spline surface of degree 1 in one of the parameters.

SURF_OF_REVOLUTION

A bounded portion of a surface of revolution.

TOROIDAL_SURF

A torus, or portion of a torus, represented by a B-spline surface.

UNSPECIFIED

A surface for which no particular form is specified.

Table A

8.9.2.4.3 Formal representation

TYPE IfcBSplineSurfaceForm = ENUMERATION OF
(CONICAL_SURF
,CYLINDRICAL_SURF
,GENERALISED_CONE
,PLANE_SURF
,QUADRIC_SURF
,RULED_SURF
,SPHERICAL_SURF
,SURF_OF_LINEAR_EXTRUSION
,SURF_OF_REVOLUTION
,TOROIDAL_SURF
,UNSPECIFIED);
END_TYPE;

8.9.2.4.4 References

Edit on Github

3 contributor(s): ArturTomczakbSI-BotDion Moult
Last change: Improve definition split (#876) * bring back headers headers were previously removed by mistake, now bringing them back * add new lines and rename the tag add the word 'short' in it * unify newlines make exactly one newline before and two after the tag * resolving typos Because bringing back headers required to go back in time to previous version, I'm now re-resolving the issues: #861, #860, #856 by ArturTomczak on 2024-07-16T16:07:28+02:00

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8.9.2.4.5 Changelog

8.9.2.4.5.1 IFC4

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