TerraTracer

TerraTracer converts land certificates (BLM mining claims, property deeds, survey descriptions) into precision GIS polygon maps. It takes bearing + distance sequences from legal descriptions and outputs KML (Google Earth) and GeoJSON (GIS tools) files.

Repositories

Location	Type	URL
GitHub	Primary	YourGitHubUsername/TerraTracer
Gitea	Mirror	git.argobox.com/InovinLabs/TerraTracer
ArgoBox	Web App	/playground/terratracer

Architecture

Python CLI (primary)

Core engine: core_geodesic.py — uses geographiclib (Karney/WGS84 ellipsoidal model) for sub-inch accuracy at any distance.

Input: Tie point (lat/lng) + sequence of bearing/distance segments from land certificate descriptions.

Output:

• KML file (Google Earth visualization)
• GeoJSON file (GIS tool import)
• Matplotlib plot (visual verification)
• CSV coordinates

Key libraries: GeoPandas, GDAL, Matplotlib, geographiclib

Test coverage: 43 pytest tests — all passing. Core geodesic accuracy verified: 0.007ft closure on rectangle, 0.076ft on lode claim.

Web App (/playground/terratracer)

Browser-based port of core logic using haversine (spherical) approximation. Sufficient for typical claim sizes (<50km) with <0.1% error.

Layout:

┌────────────────┬──────────────────────────┐
│ Input Form     │ Leaflet.js Map           │
│ (left, 400px)  │ (right, flex-grow)       │
├────────────────┴──────────────────────────┤
│ Export Bar: KML | GeoJSON | Copy Coords    │
└───────────────────────────────────────────┘

Features:

• Tie point input (decimal degrees or DMS)
• Add/remove bearing+distance segments
• Real-time polygon drawing on map as segments are added
• Clickable vertices with coordinate info
• Area and perimeter display
• KML and GeoJSON download
• Pre-populated demo: 4-segment rectangle near Washington DC

CDN dependencies: Leaflet.js 1.9.4 (map), CARTO dark tiles (basemap). No npm dependencies.

Use Cases

1. Mining Claims — Convert BLM land certificates to plottable polygons
2. Property Boundaries — Map deed descriptions for real estate
3. Drone Flight Paths — Define survey boundaries from legal descriptions
4. Survey Verification — Cross-check surveyor reports against legal descriptions
5. Rockhounding — Map mineral rights boundaries
6. Historical Research — Digitize old paper certificates

How It Works

1. Input — Enter starting tie point coordinates + bearing/distance sequence from legal description
2. Calculate — Geodesic forward calculation: each bearing+distance from current point produces next point
3. Export — Download KML (Google Earth), GeoJSON (GIS), or copy coordinates

Known Issues

• Vincenty method broken: Missing geopy_distance import in computation.py — use Karney (default) instead
• KML color format: Has # prefix but should be plain aabbggrr (ABGR format)
• Dead code: Unreachable code after return in order_points()
• Tkinter dependency: GUI mode fails in headless environments
• Web app area calc: Shoelace formula on lat/lng gives square degrees, not meters — needs projection fix

Future: PDF OCR Pipeline

Planned feature to scan PDF land certificates → OCR → parse bearing/distance sequences → auto-populate TerraTracer segments → generate polygon. Not yet built.

Related

• ArgoBox Projects — Public project showcase
• Playground Control — Lab environment management