CKey locator format v0.14.0 (draft)

Status: experimental reference profile. Encoder output uses format=14 (0E) and profile=1. Historic locator formats 8 and 11--13 remain decoder-readable.

Corner finders

The field is 29 by 29 units with a continuous 0.65-unit rounded-square border from (0.5,0.5) to (28.5,28.5), radius 3.5. Each finder is one broad, round-capped arc inside that border. Its local top-left centre is (4.0,4.0), radius 2.30, width 0.80; its reflected instances occupy the other corners. The arc follows the upper-left exterior quadrant from (1.70,4.0) to (4.0,1.70), so its open/concave mouth faces down-right toward the polar ring matrix. The other three corner arcs are continuous. The top-left arc is split at 225 degrees with a cap-compensated 0.95-unit visible gap, which is the orientation signature. All 6 by 6 corner envelopes are reserved.

Profile 2 and Profile 3 use this same normalized construction: one inboard arc per rounded corner, a continuous outer border, and the top-left split. Their geometric scale changes with their physical field; it does not change the one-arc semantic or its orientation.

Remaining rules

Grid, Ray, and Ring Keys; 72-slot polar rings and ray band; payload placement; and the 16-byte locator capacity are unchanged. The frame is C7 4B 0E 01 00 10, payload, then CRC-32C; it is systematic shortened RS(77,26) over GF(256), polynomial 0x11D, with 51 parity bytes and a 25-unknown-byte-error bound. An image reader uses structural key/finder evidence to fit geometry but accepts a payload only after RS and CRC checks.

The normative vector is locator-v14.json.