# Progress: Explorer M2 Fix 1

Last visited: 2026-10-01T20:45:00Z
Status: Completed - Investigation Complete, Reports Written

## Completed Steps
- [x] Received dispatch assignment and appended to DISPATCH.md
- [x] Initialized BRIEFING.md and progress.md
- [x] Reviewed ORIGINAL_REQUEST.md (R2), reviewer_m2_2 handoff, challenger_m2_1 handoff
- [x] Inspected existing client implementation: `client/webapp/js/engine/tile_map_renderer.js`, `tools/perf/stress_test_lru_cache.js`, `tools/perf/map_render_benchmark.js`
- [x] Formulated mathematical modeling for 8x8 vs 16x16 chunks across all aspect ratios (390x844, 844x390, 880x420, 1920x1080)
- [x] Disproved that 12-14 slots for 8x8 chunks eliminates thrashing (showed it thrashes on 33.8%–55.5% of the map)
- [x] Derived O(1) Diamond-Metric Culling algorithm reducing peak visible chunks from 9 to 7-8
- [x] Built working prototypes for 8x8 (16 slots) and 16x16 (8 slots) and verified zero stationary re-bakes
- [x] Produced comprehensive `report.md` with complete mathematical proofs and design recommendation
- [x] Produced 5-component `handoff.md`
- [x] Notified parent agent via `send_message`