| name | png-to-webp |
| description | Convert a PNG (or other Pillow-readable image) to WebP — the enforced image format for SWUStats assets. Use when adding/replacing any raster asset (board backgrounds, icons, art) that is currently a .png/.jpg, or when asked to "make this a webp". Supports a quality param (1-100, default 70), optional resize, and producing the <base>.webp / <base>-mobile.webp board pair. Orchestrates DevTools/png-to-webp.py. |
PNG → WebP
WebP is the enforced raster format for SWUStats assets going forward. This skill wraps
the one-time tool DevTools/png-to-webp.py (built once; reused for every conversion).
Input: one or more image paths.
Output: <base>.webp beside each input (or --output PATH for a single input).
Dependency (once per machine)
Needs Pillow with WebP support. Verify:
python3 -c "from PIL import Image, features; print('webp:', features.check('webp'))"
If it prints webp: False or Pillow is missing:
python3 -m pip install --quiet pillow
Usage
Basic (quality 70 default), writes foo.webp next to foo.png:
python3 DevTools/png-to-webp.py path/to/foo.png
Common flags:
--quality N — WebP quality 1-100, default 70. Lower = smaller file.--output PATH — explicit output path (single input only).--lossless — lossless WebP (crisp line art / icons; larger).--resize WxH — fit within WxH, preserving aspect (e.g. --resize 1200x2000).--delete-src — remove the source file after a successful convert.
Batch several files at quality 80:
python3 DevTools/png-to-webp.py Assets/Icons/a.png Assets/Icons/b.png --quality 80
The tool prints the size before/after and the % saved, and exits non-zero if any file fails.
Board backgrounds — the <base>.webp / <base>-mobile.webp pair
Board art follows a convention (see SWUSim/Custom/GameLayoutDevice.php →
SWUBoardBackground()): the desktop/tablet layout loads <base>.webp and the phone
layout loads <base>-mobile.webp. When adding or swapping a board, produce both
from the source PNG:
# desktop full-res
python3 DevTools/png-to-webp.py Assets/Boards/SWUSim/<name>.png --quality 70 \
--output Assets/Boards/SWUSim/<name>.webp
# mobile portrait variant (downscaled)
python3 DevTools/png-to-webp.py Assets/Boards/SWUSim/<name>.png --quality 70 \
--resize 1200x2000 --output Assets/Boards/SWUSim/<name>-mobile.webp
Then point SWUBoardBackground()'s $base at ./Assets/Boards/SWUSim/<name>.
Verify
Read the output .webp back (the Read tool renders it) to confirm it looks right and
transparency was preserved before deleting any source.
