- fit.py: centre each glyph and scale it so its furthest ink sits at INK_RADIUS = 340px, compensating the unscaled stroke width - style.py: INK_RADIUS plus INK_RADIUS_DP for vector-drawable consumers - labels.py/_label_widths.py: LABELS registry; names start with a capital, ASCII letters only, <= 10 chars, <= 522 wide in the Pixel launcher font - drop centre_offset, safe_box_overflow and the CLI safe-box warning - add prompt-bubble (sufler) and camera (macro_cam) glyphs and apps Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_012kQ5PCKqBHAkAVkPSvp6dk
3.4 KiB
app_icons — shared launcher icons for the Flutter apps
One icon family across every Flutter/Dart app: a charcoal #211D1B field with
a single glyph in the shared unified-design-system accent (#B8862E),
drawn at one stroke weight and optically centred so a row of them lines up.
Commands
# what is registered
PYTHONPATH=~/src/testsAndMisc python3 -m python_pkg.app_icons list
# contact sheet for visual review: full size / circle-masked / 48dp
PYTHONPATH=~/src/testsAndMisc python3 -m python_pkg.app_icons preview -o /tmp/sheet.png
# write assets into every app repo and rebuild the Android mipmaps
PYTHONPATH=~/src/testsAndMisc python3 -m python_pkg.app_icons generate --android
# one app, plus the hicolor PNGs for a Linux desktop target
PYTHONPATH=~/src/testsAndMisc python3 -m python_pkg.app_icons \
generate --app todo --android --linux-out ~/src/todo/linux/icons
# overwrite web/favicon.png + web/icons/Icon-*.png (apps with a web/ dir);
# the maskable ones are safe because INK_RADIUS (340px) sits inside the 40%
# (410px) maskable circle
PYTHONPATH=~/src/testsAndMisc python3 -m python_pkg.app_icons \
generate --app tutor --android --web
What gets written
Per app, into <repo>/assets/icon/:
| Layer | Purpose |
|---|---|
icon |
Charcoal field + glyph. Legacy square launcher icon and Linux icon. |
icon_foreground |
Glyph only, transparent. Adaptive-icon foreground layer. |
icon_monochrome |
Glyph only, white. Android 13+ themed icons. |
Both an .svg source and a 1024px .png are written for each, so a build
never needs rsvg-convert. flutter_launcher_icons then turns the PNGs into
the density buckets and mipmap-anydpi-v26/ic_launcher.xml.
Design constraints that bite
- Negative space ≥ half the stroke weight. Strokes closer than that merge into a solid blob at launcher size. A fork whose tines sat exactly one stroke width apart rendered as a tulip.
- Every glyph fills the same circle.
fit.placementcentres the ink and scales it so the furthest inked pixel sitsstyle.INK_RADIUS(340px, 24.4dp) from the centre; the stroke width is divided by the scale so strokes stay 72px. Check negative space at that final scale, since big drawings shrink. - Stroked outlines can read wrong. A stroked three-tine fork reads as a trident; a filled fork-and-knife pair reads as cutlery. Prefer a filled silhouette when the outline is ambiguous.
- Glyph position and size inside the fragment are irrelevant. Only the shape matters.
- Launcher names live in
labels.py: a capital first letter, ASCII letters only, ≤ 10 chars and ≤ 522 wide in the launcher font (_label_widths.py), because the Pixel app drawer cuts wider names.
Adding an app
See the app-icon skill (~/.claude/skills/app-icon/SKILL.md) for the full
procedure. In short: add a glyph to glyphs.py, register the app in
apps.py, wire flutter_launcher_icons into its pubspec.yaml, generate,
review the contact sheet, then verify on the phone.
Tests
cd ~/src/testsAndMisc
python3 -m pytest python_pkg/app_icons --cov=python_pkg.app_icons \
--cov-report=term-missing
External tools (rsvg-convert, magick, dart) are mocked; the suite needs
none of them installed.