Designing VORSA-M3 for one hardware pass

The mapper shaped the detector before accuracy charts did.

Local capacity 3

Each grid point can describe up to three objects. Output layout: M·(8+C)+3. Centres may move −0.5…+1.5 across a field boundary to reduce edge artefacts.

Angles

Orientation is sin(2θ)/cos(2θ). The augmentation self-test found a sign error invisible at 90/180/270° and exposed at 45°.

Permutation assignment

For M≤4, try all slot permutations (M!≤24) rather than adding a heavy assignment solver.

Post-processing

Slot-aware Soft-NMS; overflow is reported instead of hidden; focal objectness addresses ~1:500 slot imbalance; p_koinzident generates local overlap cases.

Mapping

V6 = one sequence / one pass / 18 of 32 NPs, measured 2026-08-26, BC.A1.003.009, MetaTF 2.19.3. Negative X variants must fail.