# World Clock: reference coverage

The Andrew Clock archive contains 97 HEIC photographs and two MOV videos. All photographs were indexed; individual frames around the city drum and pavement were inspected. Original files and incidental people are not published. Isolated city-panel and column-map crops are used as textures.

## City inscriptions

All 24 photographed positions are transcribed in [clock-plates.json](clock-plates.json), with source filenames. Numbering describes the hour-band alignment in the photographs, not permanent city-to-hour assignments: the band rotates beneath fixed city plates.

The transcription preserves engraved names rather than substituting a modern city/time-zone database. IMG_5062 confirms Jekaterinburg, Aschgabat, Bischkek and Duschanbe on one upper facet; Taschkent belongs to the next. New Delhi and Colombo have +30 minute corrections; Karachi does not. The date-line inscription spans the lower Kamtschatka / Kap Deschnew neighborhood.

All 48 upper/lower panels use manually rectified 512×640 textures sampled from original-resolution photos. Source corners and edge corrections are retained in [clock-texture-manifest.json](clock-texture-manifest.json). Broad illumination normalization reduces exposure differences while preserving photographed lettering and weathering. The crops exclude folded trim, which is modeled separately; fixed panel dividers stop before the rotating hour band. The HTML reader remains available while textures load or if WebGL fails. Perspective residuals and source reflections remain: these are not physically calibrated material scans.

## Pavement

IMG_5111, IMG_5118, IMG_5122, IMG_5125 and IMG_5129 document the 16-point German compass, red-brown bearing ring, pale outer border and alternating inner tiles. O means east. Full-resolution IMG_5122 reads **90**, correcting the earlier published reading of 100. IMG_5111 shows NW at 45 and adjacent 60/30; IMG_5118 shows S at 0 and an adjacent 15.

The reconstruction uses a mirrored 0–90 sequence in 15-degree steps and 48 alternating tile sectors, consistent with those visible quadrants. It is not a claim that every worn or occluded mark has been individually transcribed. Letter outlines, aggregate pattern, joint placement and radial proportions are procedurally approximated. Absolute alignment of the pavement to the city drum is not surveyed.

The current compass is a pre-rendered reference-led texture, with custom thin-outline N/O/S/W glyphs and photo-sampled stone grain. Numeral contrast is slightly enhanced for legibility. A multi-photo stitch was rejected because it retained equipment and inconsistent ring boundaries. [Compass provenance](compass-provenance.json) distinguishes reconstruction from source photography. Texture north maps to world −Z and stays fixed when the drum alignment changes.

## Column engraving

Four isolated photo regions now wrap the cylinder: IMG_5090 (North America), IMG_5093 (South America), IMG_5096 (Europe/Africa) and IMG_5102 (Asia/Australia). This replaces the placeholder grid. [Column provenance](column-map-provenance.json) preserves every source crop. Region joins, latitude registration and longitudinal proportions remain approximate; this is not a surveyed continuous unwrap. The plain upper band leaves room for the separately modeled analogue clocks.

## Remaining differences

- The supplied collection now covers the full circumference; missing source coverage is no longer the reason for blank city faces.
- Column-map seams remain visible at close range, and the precise engraving-to-compass orientation is not established.
- Dimensions, orbit inclinations, planet positions and the exact underside lamp arrangement remain reconstructed, not measured.
- The hour band's changing colors are matched by eye. Numerals, square markers and metal trim remain modeled approximations.
- Ground view hides the structure above the pavement for inspection.
- Hour-band playback is accelerated; the solar assembly rotates once per real minute during playback.

This is an improved photo-led reconstruction, **not yet an exact replica**.

## Performance and access

Three.js is self-hosted. Rendering occurs on interaction, image load or deliberate playback; there is no idle animation loop. Pixel density is capped at 1.5. Touch, keyboard and camera presets remain available, with a full-size HTML reader for small engraved text. The reference archive itself is not downloaded by visitors.

The 3D viewer and geometry lab share one phase, alignment and selected-face state. A 600-case coordinate test compares plan bearings with the modeled 3D rotation. The 336 gold hour markers use one instanced draw; photo loading is limited to six concurrent requests. Preset changes have short camera transitions, disabled for reduced motion.
# English compass display

At Andrew's request, the modeled rose and Geometry Lab use E for east, including NNE/NE/ENE/ESE/SE/SSE. This is an explicit localization of the photographed German O (Ost), not a claim about the monument's lettering. North = −Z, east = +X; bearings increase clockwise. The same texture is used in both views. The original mirrored quadrant scale remains: 0° at north/south and 90° at east/west, distinct from the 0–360° bearing control and hour-ring minute corrections.