IFC 4.3.2.20240904 (IFC4X3_ADD2) under development

Annex E
(informative)

Examples

E.1.5 - Cube Advanced Brep

Example overview

The examples demonstrate the use of various geometric shape representation types to express a simple geometric form of an element. The examples of advanced geometric shape deal with CSG having Boolean operations, advanced swept solid and advanced brep representations. in some cases, the same geometry is also provided as faceted brep or tessellation to compare the results.

The advanced brep representation using NURBS is shown in Figure E.B. It shows a twisted cube resulting in b-spline surfaces at four sides. The cube itself is exported as a proxy element.

advanced_brep_2.png
Figure E.B — Advanced shape represented as advanced Brep

IFC-SPF source 

ISO-10303-21;
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END-ISO-10303-21;

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