The current skybox is a 3200 × 1600 lossless WebP, assembled from four overlapping imagegen strips. Each strip covers 108 degrees horizontally and the full 180-degree vertical range. The centres are 90 degrees apart, giving 18-degree overlaps.
The original unmodified v1 panorama supplied layout-guide crops. Imagegen was asked for its largest native output, with a requested 2304 × 3840 portrait size, but actually returned 971 × 1619 for city, hills and sunward, and 972 × 1619 for woodland. The built-in tool exposes no explicit size parameter. These limits are recorded rather than presenting the requested size as achieved.
The stitch uses the native detail without enlargement: inputs are slightly reduced to 960 × 1600, blended into 3200 × 1600, and saved losslessly. Compared with the original 1774 × 887, this is approximately 1.8 times the linear sampling resolution and 3.25 times the pixel area. This describes sampling density, not a claim that every generated feature is accurate.
Sources, exact prompts, stitch metadata and the PNG master: ../../../output/imagegen/sylir-skybox-strips-v1/.
Reproduction: node scripts/stitch-skybox-strips.mjs from the app folder, with FFmpeg installed. The script refuses to overwrite existing master and runtime assets; use a new version for future experiments. Existing v1 and v2 assets are retained.
The joins use two frequency bands and minimum-error seam paths, including the circular final overlap. Polar caps fade to shared row colors. The scene still uses the city toward the throne end, the same sun direction, and the panorama for reflections. No building geometry or user controls were added.