GPX Route Mapper (by Grok)

gpx-route-mapper-grok — a fully client-side OpenStreetMap tool for drawing routes with the mouse and exporting them as GPX.

Features

• OpenStreetMap basemap via Leaflet
• Click-to-add points or freehand drag drawing
• Line smoothing (Catmull-Rom spline + iterative sharp-corner removal) via checkbox
• Google Maps–style search with autocomplete (start + optional destination)
• A / B markers on start and destination when both (or either) are set — geocoded with Nominatim
• Zoom + / − controls
• Export GPX (track) as a downloadable file — no server required

Run locally

Any static file server works. Examples:

# Python
python3 -m http.server 8080

# Node
npx serve .

Then open http://localhost:8080.

You can also open index.html directly in a browser; search may be limited by CORS depending on the environment. Serving over http://localhost is recommended.

Usage

1. Search — type a place in Start (and optionally Destination). Pick a suggestion or press Find. The map pans/zooms and places green A / red B markers.
2. Draw — use Click points to drop vertices, or Freehand to drag a path.
3. Smooth — toggle Line smoothing to remove all sharp corners before export.
4. Export GPX — prompts for a route name (prefilled from Start/Destination when set), then downloads a .gpx track.

Tech notes

Piece	Implementation
Map tiles	OpenStreetMap (tile.openstreetmap.org)
Geocoding	Nominatim public API (rate-limited; fine for personal use)
Drawing	Custom Leaflet mouse/touch handlers
Smoothing	Centripetal Catmull-Rom + iterative corner cuts until turns ≤ ~6°
GPX	Generated as XML and downloaded via Blob

No backend, API keys, or build step required.

Nominatim usage

Please respect Nominatim usage policy: debounce is already applied; do not hammer the service with bulk/automated geocoding.

License

MIT — use freely for personal or commercial projects.