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items-sheet-sprites

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Add or regenerate 16×16 item/resource icons on items-sheet.png (Pillow), align with game-shared asset coords, InteractableTexts, and optional interactableDisplayName. Use when adding new pickup sprites, patching the items atlas, or fixing misaligned tiles.

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How to use this skill

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  1. Open your project in Codex.
  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
Prompt to paste
I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/webdevcody/survive-the-night-game/blob/HEAD/.cursor/skills/items-sheet-sprites/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/items-sheet-sprites/. Do not write files or run scripts until I approve.

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Items sheet sprites (16×16)

Context

Grid rules (avoid broken UVs)

  • The sheet width is commonly 160px → 10 columns; valid x positions are 0, 16, …, 144. Do not use x ≥ 160 for a 160px-wide sheet (the rightmost16×16 cell starts at x = 144).
  • If you need a new row, extend the PNG height by 16 (or more) and place the tile at (column * 16, newRowY).
  • After resizing the sheet, ensure no other configs still assume an old height (search for y: values in shared entity configs).

Recommended workflow: patch script

The repo maintains a reproducible painter:

  1. Open scripts/patch-items-sheet-sprites.py.
  2. Add a spr_your_item() function that returns a RGBA Image of size (16, 16) (use Image.new("RGBA", (16, 16), (0,0,0,0)) and ImageDraw / pixel loops). Reuse palette constants at the top of the file for visual consistency.
  3. Append (pixelX, pixelY, spr_your_item) to the PATCHES list.
  4. If the new pixelY (plus16) exceeds the sheet height the script uses, update main() so nh (new height) is at least pixelY + 16 (the script already does max(oh, 224) — raise the floor or compute max(oh, max_y + 16) for all patches).
  5. Run from repo root with Pillow available:
python3 -m venv .venv-sprite
./.venv-sprite/bin/pip install pillow
./.venv-sprite/bin/python3 scripts/patch-items-sheet-sprites.py
  1. Commit the updated PNG and script. Remove .venv-sprite if you do not want a local venv in the tree (add .venv-sprite/ to .gitignore if you keep regenerating).

Alternative: one-off Pillow script that opens the sheet, pastes a 16×16 tile at (x, y), and saves — same rules; prefer extending patch-items-sheet-sprites.py so art stays reproducible.

Wire-up after the pixel lands

  1. Set assets.x / assets.y / assets.assetKey on the item or resource config to match the pasted cell.
  2. Pickup / Interactive encoding: Generic entities use interactableDisplayName (see BehaviorConfigs) or derive id with underscores → spaces. That string must exist in InteractableTexts (append at the end only — wire ids are declaration order).

Related scripts

Example: zombie skin

zombie_skin was placed on a new row at (0, 240) after extending the sheet to 256px tall, with coords updated in RESOURCE_CONFIGS. New icons should follow the same pattern if the sheet runs out of empty cells on existing rows.