Recipe: seamless tileset

N unique seamless tiles packed into a sheet, with matching Tiled .tsx (tileset) and .tmj (sample map) files so you can drop it straight into the editor.

What you get

`overworld.png` — 4 tiles (grass, dirt, stone, water), 32×32 each, db32 palette. Preview is 4× nearest-neighbor upscaled.

The same directory contains overworld.tsx (Tiled tileset) and overworld.tmj (10×10 sample map painted in Tiled). Both are generated automatically.

Command

python3 scripts/generate_tileset.py \
  --prompt "grass, dirt, stone, water" \
  --tile-size 32 --count 4 --columns 2 \
  --palette auto --seamless auto \
  --name overworld \
  --output-dir assets/examples/tileset_overworld/ --qa

Flags explained

Flag	Meaning
--prompt "grass, dirt, stone, water"	Comma-separated list of tile subjects. Each becomes one tile.
--tile-size 32	Side length of each tile in pixels.
--count 4	Number of tiles. Can be less than or equal to the comma count.
--columns 2	Sheet layout: 2×2 grid. Rows computed automatically.
--palette auto	Keyword match picks db32 for stone because pico8 has no mid-grey. See Palettes.
--seamless auto	Try crop → torus blend → edge_match blend, keep the variant with the lowest tile_seam_diff. edge_match forces seams to 0 as a last resort.
--qa	Runs seam continuity + palette fidelity gates.

QA gates checked

• tile_seam_diff_mean < 12.0 per tile (hard) — wrap-edges match, so placing adjacent copies in Tiled shows no seam.
• palette_fidelity == 1.0 (hard).
• alpha_crispness >= 0.999 (hard).

Drop into Tiled

tiled assets/examples/tileset_overworld/overworld.tmj

Paint a room at 10×10 tiles; boundaries between tiles should disappear. If a particular tile shows a visible seam, rerun with --seamless edge_match to force continuity.

Tips

• Keep tile count ≤ 8 per sheet for readable prompts. For larger sets, generate multiple sheets and merge in Tiled.
• For terrain variations (corners, transitions), run multiple generations with different prompts and pack manually. 47-tile Wang blob sets are deferred to a future script.
• --bleed N adds 1-px edge extrusion between tiles — useful for Unity/Godot to stop sub-pixel bleed when textures filter at runtime.