PROCITY/docs
m3ultra 47f05ecaa8 Lane D R23 (v5.0-alpha): the GIG_RANGE chunk-neighbour fix — scoped to the gig path (ledger #6)
My carried v4.x finding, fixed post-release as scheduled. Runtime-only: no plan, no
golden, no flag, no fetch. selfcheck ALL GREEN 161300/161300, 0x3fa36874 frozen.

THE FINDING GREW WHILE IT WAITED: filed at 8.7% (measured at katoomba's isolated pub);
A's R21 cluster bias made it WORSE — venues now sit inside the retail cluster where peds
converge from every side, so 42.6% of in-gig-range peds (5094/11971) were chunk-blind.

THE OVERRIDE (measurement wins): the brief asked for "extend to chunk + 8 neighbours"
AND "byte-identical flags-off". I built the literal version and measured that those
cannot both hold: on the synthetic town (what ?classic=1 boots, gig layer absent) a full
3x3 scan sourced 127 of 855 finds (14.9%) from neighbour chunks — finds v2 never made.
The frozen v2 crowd would shop ~15% more. Covenant breach, in a clause of the same brief.

So the fix is scoped to the GIG path — which is what I actually filed:
- ordinary shops: own chunk only (v2 semantics, frozen — noticed from its own block)
- gig venues: the full 34m radius, honest across chunk edges ("follow the sound" is the
  whole reason GIG_RANGE 34 > PATRON_RANGE 18)
- no gig on -> _gigVenues empty -> neighbour loop skipped entirely -> ?classic and every
  flags-off boot take the IDENTICAL code path and cost to v2. Byte-identical BY
  CONSTRUCTION, not by measurement luck.
Both ranges < CHUNK(64) so 3x3 is exact, not approximate; fixed dz/dx order keeps ties
deterministic as the old single-list scan was.

BEFORE -> AFTER: cross-chunk in-range peds seeing the gig 0% (structural: v2 scanned only
the ped's own chunk) -> 100% (katoomba 4/4, fitzroy 11/11). Same-chunk unchanged 100%.
Classic neighbour-sourced finds: 0 (127 under the rejected full scan). Determinism
identical. 0 NaN on katoomba/fitzroy/synthetic. Sim 0.056 -> 0.057 ms/frame (+2%, i.e.
0.006% of a 16.7ms budget); lookup 0.58us unchanged with no gig, 1.3-2.7us with a gig on
(fires per PATRON_STRIDE, not per frame). Fitzroy clean at 376 peds.

CARRIED, documented: PATRON_RANGE keeps v2's own chunk-blindness — fixing it costs the
classic covenant, and the covenant wins. A frozen v2 quirk now, not an oversight.
Known minor: a scheduled-but-closed gig still runs the loop for nothing (0.58->1.3us).

D->F: no blocker for v5.0-alpha; classic untouched by construction.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-16 23:06:07 +10:00
..
LANES Lane D R23 (v5.0-alpha): the GIG_RANGE chunk-neighbour fix — scoped to the gig path (ledger #6) 2026-07-16 23:06:07 +10:00
shots Lane F R22 (v4.0 — THE EPOCH CLOSE): the re-measure, the selector, the release tour, the tag 2026-07-16 22:32:32 +10:00
A-progress.md Lane A round 23 (v5.0-alpha): the spacing warn — D's thin-tail finding as law (ledger #5) 2026-07-16 23:04:43 +10:00
CITY_SPEC.md Lane A round 23 (v5.0-alpha): the spacing warn — D's thin-tail finding as law (ledger #5) 2026-07-16 23:04:43 +10:00
RESEARCH.md PROCITY scaffold: spec, research, 6 Opus lane prompts, core modules, vendored three r175, 69 inherited skins 2026-07-14 10:46:40 +10:00
RETRO_V4.md Fable (integrator): the v4 epoch retro — what worked, what cost us, the v4.x ledger, the v5 recommendation 2026-07-16 22:39:47 +10:00
V2_IDEAS.md Lane F: integration — interiors + keepers + street peds + QA harness 2026-07-14 14:29:03 +10:00
V3_VENUES.md Fable (integrator): v3 epoch charter — venues & gigs (John's pick) 2026-07-15 14:18:26 +10:00
V4_REAL_MAP.md Lane A round 22: CITY_SPEC v4 amendments final + charter risk-list retired-or-carried (ledger #6) 2026-07-16 22:01:31 +10:00
V5_REAL_SHOP.md Fable (integrator): v5 THE REAL SHOP charter + round-23 instructions — v5.0-alpha THE FIRST REAL CRATE 2026-07-16 22:48:59 +10:00