README.md

Example artwork

All five examples use a shared forest-adventure art set generated with the built-in image-generation tool in Codex. The original PNGs are in sources/; the full prompts and generation metadata are preserved in generation.json. These are new illustrations, not edits of the previously bundled third-party graphics.

Runtime files live in each example's assets/ directory and are packed into MPX normally. High-resolution source images are not included in game asset packs.

Reproduce runtime assets

From the repository root, with requirements.txt installed:

python tools/prepare_example_art.py
python tests/example_art_tests.py
python tools/build_examples.py
python tools/capture_examples.py --update-docs

Use --target linux-x64 on the last two commands for Linux. Preparing the checked-in sources is deterministic and requires neither image generation nor an API key. New AI generations are not expected to reproduce identical pixels from the prompts.

The preparation script performs only the user-approved cropping, scaling, and sheet assembly. Most graphics use nearest-neighbor sampling; foreground foliage uses area sampling while reducing the detailed originals to retain thin leaves. Animation groups share a scale and baseline, retain transparent backgrounds, and have a one-pixel frame margin. Sprite proportions are preserved; terrain textures fill their tile cells. The native 64px trees have a two-pixel margin and a 62px baseline, preserving their previous world footprint. They render 1:1, not as enlarged 32px thumbnails. Bushes remain native 32px sprites. Backgrounds, terrain, rocks, characters and animations are unchanged by this foliage preparation. Screenshots render 60 actual headless engine frames so characters settle onto platforms before inspection.

The rock cell uses an explicit bottom crop at source y=430 (on the 1024px-tall atlas): the next row's pine tip intrudes into the nominal first-row cell. Keeping that fragment would align the fragment, rather than the rock, with the ground. The art tests check continuous opaque contact above the rock's baseline.

Source	Layout	Runtime use
player.png	4 x 2	Eight 32px frames; 16px derivatives for smaller demos
player_run_balanced.png	4 x 2	Eight run phases, common scale and hood registration; equal contact/support/push/flight half-strides
coin_spin.png	4 x 3	Twelve phases including front, edge, and back; 1.2-second rotation
portal_loop.png	4 x 3	Twelve interior energy phases; 1.8-second loop
enemy.png	4 x 2	Four slime and four bat frames
terrain.png	4 x 3	Mossy top tiles, dirt, and platform textures
decor.png	3 x 2	32px props plus two native 64px trees in tree_sheet.png
objects.png	3 x 2	Two coins, two portals, fern, sign
bg0.png / bg1.png / bg2.png	Single landscapes	Morning, autumn, and moonlit backgrounds
near.png	Three rows	Transparent foreground forest strips

The older player_run.png and player_run_push.png sources are retained for provenance but are no longer used. The separate long-legged push pose caused a visible imbalance. Run sprites are now registered by the hood at a common scale, not centered independently by the changing foot/scarf silhouette. Flight poses retain their raised feet. Coins use an independent smooth, small floating offset; the rotation never changes their vertical position. All runtime sheets are baked during art preparation; gameplay only selects frames from the packed sheets.

tests/example_art_tests.py checks dimensions, alpha, sprite frame bounds, and manifest paths. tools/capture_examples.py checks all five demos plus the three Jump and Run levels, and produces build/example-previews/overview.png for visual inspection. Both are exercised by CI. Geometric tests cannot replace visual review of newly generated characters or animation poses.

Older attribution files in jump-and-run/assets/ remain as historical documentation for earlier releases; they do not describe the replacement graphics. Example audio is unchanged and retains its existing CC0 notice.