# Sprite assets

Art: [Kenney's Robot Pack](https://kenney.nl/assets/robot-pack) (CC0 — no
attribution required, credited here anyway), the green side-view robot.
Source pack lives at `~/Documents/kenney_robot-pack`; only the frames listed
below were copied in.

Convention the loader (`bolt_pet/ui/sprite.py`) expects:

```
assets/sprites/
  idle/        frame_00.png                    robot_greenBody   (standing)
  listening/   frame_00.png, frame_01.png       robot_greenDrive1/2 (tracks rolling — "leaning in")
  thinking/    frame_00.png, frame_01.png       robot_greenDamage1/2 (flicker — "processing")
  talking/     frame_00.png, frame_01.png       robot_greenBody, robot_greenJump (bounce)
  error/       frame_00.png                     robot_greenHurt
```

- One subfolder per pet state (matches `bolt_pet.state.PetState`).
- Any `*.png` filenames work — they're played back in alphabetical-sort
  order, looping, at `IDLE_ANIMATION_FPS` (see `.env`).
- Frames are scaled to fit within `PET_SIZE` (default 160px), keeping aspect
  ratio, and centered in the (square) pet window — the source art here isn't
  square, so don't assume it fills the frame edge-to-edge.
- A state directory with no frames in it falls back to a small
  procedurally-drawn placeholder blob (see `_placeholder_frames` in
  `sprite.py`).

## Swapping in different art

Replace any state's PNGs (same alphabetical-order-loops convention) to
change its look — no code changes needed. If your source is a single grid
spritesheet (rows/cols of frames in one PNG) rather than one-file-per-frame,
use `scripts/slice_spritesheet.py` to cut it into this folder-of-frames
convention:

```bash
python scripts/slice_spritesheet.py path/to/idle_sheet.png assets/sprites/idle \
    --cols 6 --rows 1
```

If your format is something else entirely (a single animated GIF/APNG, a
Spine/DragonBones skeletal export, an Aseprite `.json` atlas, etc.) — tell me
the format and I'll adapt `sprite.py`'s loader rather than making you convert
by hand.