# Building a Newbury Crest (marker ID 0)

A "Newbury Crest" is the physical anchor marker. It has two parts:

1. **Detector core** — a 6×6 grid of flat black & white tiles. This is the part the camera reads.
   It is an ArUco 4×4 marker (1-cell black border + 4×4 data), so it must be **exact**.
2. **Colour-wheel ring** — a decorative 1-tile-wide border of Red / Yellow / Blue around the core.
   Purely cosmetic (Hidden Side theme); the detector ignores it.

See `crest-01_buildplan.svg` for the full picture and `crest-01_buildmap.json` for the raw grid.

## The detector core (6×6) — ID 0

`#` = **black** tile, `.` = **white** tile. Build it in this exact orientation; the single
yellow corner dot in the app shows which corner is the reference (top-left here).

```
# # # # # #
# . # . . #
# # . # . #
# # # . . #
# # # . # #
# # # # # #
```

- Outer ring is **all black** (the ArUco quiet border) — do not substitute colours here.
- Use **flat tiles**, not plates with exposed studs — studs cast shadows that hurt detection.
- Suggested scale: one **2×2 tile per cell** = 16 mm cells → **96 × 96 mm** core.
  (For a crisper read at distance, go 2×2 *studs* per cell using four 1×1 tiles — finer edges.)

## The colour-wheel ring

Wrap one tile-row of Red/Yellow/Blue around the 96 mm core, cycling R→Y→B. Keep it **outside**
the black border (it can touch the black border directly — black separates it from the data).

- Red `#F65151`  ·  Yellow `#FFF35D`  ·  Blue `#529EFF`
- These are the exact Hidden Side ghost-lure gradient tops, so it reads as the colour wheel.

## Mounting

- Mount flat on a black baseplate, flush and rigid (no warping — a curved marker breaks pose).
- Matte tiles beat glossy if you have the choice; glare is the main real-world enemy.
- Place at "street level" where a phone naturally frames it as part of the scene.

## Test before you commit

1. Print `crest-01_aruco0.svg` at ~100 mm and tape it down.
2. Open `ar-test.html` on your phone (over HTTPS), point at it.
3. HUD should show **id: 0** and a blue wisp should hover above it.
4. Try angles, distance, and your real exhibition lighting. If it holds lock well, build the
   LEGO version with confidence; if glare is an issue, matte it down.