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.