Frontend: Vanilla ES6 modules, HTML5 Canvas 2D (double-buffered with dynamic overlay).
Coordinate System: Game engine coordinates (meters), origin at bottom-left, mapped via Matrix and View transforms.
Datasets:
- catenary_dv.json: 164 chained polylines (optimized from 3,751 segments), 9 traction substations, 5 neutral sections, 34 interruption clusters, 129 warning signs.
- trackdata_dv.json: Rail tracks (cubic Bézier curves) and junction points.
- poi_dv.json: Stations, offices, service tracks, turntables, landmarks.
- shop_items.json: Shop inventories and prices.

Catenary Layer Features

Wire Suspension Rendering:
- Single (6.0m, 1500V/750V): standard solid vector line.
- Dual (6.0m, 1500V): high-capacity twin catenary stroke.
- Quad (6.0m, 1500V): heavy 4-wire mountain pass stroke with dark border.
- Trolley (6.0m, 750V): fine yard wire.
- Side Rail (4.5m, 1000V): dashed 3rd contact rail at IME and SM mine tracks.
- Neutral Sections (0V): contrasting red-and-white dashed lines with 0V danger badges.
Color Modes:
- Voltage: 1500V DC (#00d2ff), 1000V DC (#ff9f1c), 750V DC (#2ec4b6), 0V Neutral (#e63946).
- Substation: Distinct color per feeding substation (CME/IME1500, CP750, FF1500, HB1500, IME1000, IMW1500, OR750, SM1500, SM1000).
- Wire Type: Color-coded by physical suspension category.
Markers & Tooltips:
- Traction Substations: ⚡ badge with nominal voltage, supply voltage, max load (kW), and regenerative inverter presence.
- Neutral Sections: ⛔ badge with section ID, length, connecting substations, and disconnect traction warning.
- Interruption Signs: ⤓ diamond badge for pantograph drop/raise warnings.
- Contact Wires: Nearest-point hovering displaying voltage, substation feed, category, and segment length.

CommunityMapLocation Mod Integration

Rotation Desync: LocationResponse accepts rotationTransform from locomotive transform or camera heading (fixing player orientation desync).
URL Formatting: Fixed string immutability bug in address.replaceAll inside connectPlayerLocation.

In <GameDirectory>/Mods/CommunityMapLocation/Settings.xml:

<Settings>
  <Port>9090</Port>
  <RequestSourceType>Any</RequestSourceType>
  <RequestSource>http://localhost:8080</RequestSource>
</Settings>

Note: If RequestSourceType is Any, the game mod allows cross-origin requests from any web host (localhost, GitHub Pages, Gitea).

Gitea Actions (.gitea/workflows/deploy.yaml): JSON dataset validation, JS syntax verification, artifact packaging with actions/upload-artifact@v3, releases with akkuman/gitea-release-action@v1.
GitHub Pages (.github/workflows/deploy-pages.yml): Automated GitHub Pages deployment on push to main.