Struct EulerReport 

pub struct EulerReport {
    pub characteristic: i64,
    pub shells: usize,
    pub genus: Option<i64>,
    pub recorded_genus: i64,
    pub boundary_edges: usize,
    pub non_manifold_edges: usize,
}

Outcome of solid_euler.

Fields

characteristic: i64

V − E + F − H over the reduced complex — the same count BrepSolid::validate makes, with degenerate (collapsed) cells left out of all four terms.

shells: usize

genus: Option<i64>

S − χ/2, and None when characteristic is odd — there is no such surface, so there is no genus to report rather than a halved one.

recorded_genus: i64

What the solid carries in its genus field.

boundary_edges: usize

Non-degenerate edges used by FEWER than two coedges — a boundary edge, or an edge record no loop references at all. A closed surface has neither; a sheet or an in-progress shell legitimately has the first, and its characteristic is then unconstrained. Both are counted here because both mean the same thing for parity: these counts are not those of a closed surface, so decline to judge rather than convict.

non_manifold_edges: usize

Non-degenerate edges used by three or more coedges — not a 2-manifold, so the characteristic means nothing either.

Implementations

impl EulerReport

pub fn is_closed_manifold(&self) -> bool

Whether the counts describe a closed 2-manifold at all. Parity is only an invariant for one of those.

pub fn is_unsound(&self) -> bool

The HARD predicate: a CLOSED manifold whose Euler characteristic is odd.

No closed orientable surface has one — χ = 2(S − G) is even by construction — so this is a statement about the record, not about a tolerance, and it cannot be tuned away. It is the one thing the Euler count can establish on its own: the genus itself has no second derivation from the cell complex to check against.

pub fn summary(&self) -> Option<String>

One line naming what is wrong, or None.

Trait Implementations

impl Clone for EulerReport

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for EulerReport

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Serialize for EulerReport

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.