Fuel icon generation and vectorization

The premium gasoline icon was generated with the built-in image generation tool on 2026-10-09, using the existing additived-gasoline PNG as a style reference. This is original generic pump artwork, not a Petrobras/Podium logo. See the premium category contract.

Repeatable workflow

1. Inventory actual PNG/SVG inks, not only Compose text tints. Current fuel art uses orange (common gasoline/LPG), gold (additive gasoline/CNG), green (ethanol), blue (S500), violet (S10). Do not copy historical duplicate colors into a new category. Ruby/magenta #C2185B is reserved for true premium gasoline; its crown signals quality. Every future category needs one unique, meaningful category ink. White interior details and transparency are neutral.

2. View representative existing assets. Preserve front pump, rounded display, droplet, right hose/nozzle, bottom plinth, visual weight and proportions. Generate a transparent PNG first. Ask for flat solid category ink, white interior details, no text/logos/gradients/shadows. Keep the exact prompts in sources/; retain the selected raw output unchanged. Inspect alpha and shape.

3. The first premium draft was violet. Inspection of all actual icons revealed violet already belongs to S10, so the final image-generation edit changed only the ink to ruby/magenta. Only the selected final raw PNG is shipped in this repository; generation history is documented, not passed off as native vector design. The generator may still produce slight shading; normalize it deterministically before tracing.

4. Run from the repository root:

   python3 scripts/assets/trace-fuel-icon.py --source docs/assets/fuel-icons/sources/GASOLINA_PREMIUM_GENERATED.png --name gasoline_premium_grade --color '#C2185B' --size 128
   

   The script checks dominant existing hues (20-degree minimum separation), keeps original source pixels while centering on a transparent square, removes generated shading to one category ink plus white, traces both masks with VTracer spline curves, and exports the SVG through Inkscape to Android. Input masks use alpha >=128; saturated pixels are category ink, neutral interior pixels white. This is real vectorization, never a PNG embedded in an SVG wrapper. Inspect small isolated details; do not tune thresholds merely to hide a poor generation. The 20-degree guard is an asset-tool policy, not a substitute for visual/color-vision accessibility review.

5. Deliver all four artifacts: raw generated PNG in sources/, normalized PNG in transparent/, SVG master here, Android PNG under drawable-nodpi/. Gasoline icons export to 128 x 128; Compose retains its existing dp sizes. Ethanol is a historical 256px exception, not the new gasoline export target. Do not install large traced path strings directly into Android VectorDrawable: the existing set uses local PNG exports and SVG documentation masters.

6. Inspect PNG and SVG render on light/dark backgrounds at 20/24/48/128px; check crown/display/nozzle holes and padding. The provenance JSON records source SHA256, path count, dimensions, selected ink and silhouette intersection over union against the normalized master at native resolution. Require >=99%. This metric measures silhouette, not perceptual identity of every internal pixel. Compare category/white masks too before claiming complete fidelity.

7. Map the new enum to its own resource and localized label; retain textual category labels for accessibility. Check light/dark text-tint contrast and build/lint the actual APK. Never reuse the legacy additive icon/enum for true premium. Preserve existing assets and hashes.

Tools and provenance

Pillow, NumPy, VTracer and Inkscape are build-time asset tools already available on this workstation, not app/runtime dependencies. Re-run tool/license/security review before introducing new dependencies elsewhere. VTracer's spline trace settings are recorded directly in the script; raw source and prompts permit reproduction without calling the image generator again. Model generation itself is nondeterministic; do not claim a seed or exact regeneration guarantee.

Final measured metadata: provenance. The normalized master is the final one-ink PNG; the untouched generated PNG preserves model output for future investigation.