- Hybrid rasterizer: PIL scanline fill for the bulk, with cells in a
~2 px band around each ring edge re-tested exactly against the
polygon - cell-for-cell identical to the old center-in-polygon pass
(equivalence test added) but O(vertices + cells) instead of
O(vertices x cells). Measured 4.5 s -> 0.11 s at 1.45M cells with
8.8k polygon vertices.
- AMG-preconditioned CG (pyamg, new requirement) above 500k unknowns:
measured 7.0 s vs 15.3 s spsolve at 1.4M unknowns at a fraction of
the memory, R identical to 1e-6; the old Jacobi-CG (kept as fallback
when pyamg is missing) needed tens of minutes there. spsolve stays
the default below 500k where it is exact and fastest.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
janik
b62e45a9b4