IFC (IFC4X3_ADD2) under development


Semantic definition

The Surface Genus of the evaluated representation items before applying product-level geometric features such as openings and projections.

Surface Genus is a topological measure that represents the number of "holes" or "handles" on a surface. For example, a sphere has genus 0, and a torus has genus 1.

Computed using the Euler characteristic:


With the numbers of vertices (V), edges (E) and faces (F)


With surface genus (g) and the number of boundaries (b) the latter zero in case of an enclosed volume.

Referenced in
Table A

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