GeodeticOps.jl

A pure-Julia package for geodetic computations on Earth's ellipsoid. No external dependencies beyond Julia's standard library.

Features

• 7 coordinate types with automatic conversions: LLA, LLARad, ECEF, ENU, NED, AER, UTM
• Geodesic distances: Haversine (great-circle) and Vincenty (ellipsoidal, sub-millimeter accuracy)
• Forward and inverse geodesic problems via Vincenty's formulae
• Geodesic interpolation: intermediate points and midpoints along geodesics
• Polygon area on the ellipsoid using spherical excess
• Bounding boxes: axis-aligned and distance-based
• Multiple datums: WGS84 (default), GRS80, Clarke 1866, WGS72

Quick Start

using GeodeticOps

nyc = LLA(-74.006, 40.7128)
london = LLA(-0.1278, 51.5074)

# Geodesic distance
distance(nyc, london)  # 5.585e6 meters

# Bearing
bearing(nyc, london)  # 51.2 degrees

# Midpoint
midpoint(nyc, london)  # LLA(lon=-38.8°, lat=52.0°, alt=0.0m)

# Forward geodesic: 1000 km due north from the equator
forward_geodesic(LLA(0.0, 0.0), 0.0, 1_000_000.0)

# Polygon area
pts = [LLA(0, 0), LLA(1, 0), LLA(1, 1), LLA(0, 1)]
polygon_area(pts) / 1e6  # ~12,308 km²

# Coordinate conversions
ecef = ECEF(nyc, WGS84)
utm = UTM(nyc, WGS84)

All operations default to WGS84. Override per-call with datum=GRS80 or change the global default:

DEFAULT_DATUM[] = GRS80

Coordinate Types

AbstractCoords{T}
├── AbstractFixedCoords{T}       # convertible to LLA with only a Datum
│   ├── LLA{T}                   # longitude, latitude (degrees), altitude
│   ├── LLARad{T}                # longitude, latitude (radians), altitude
│   ├── ECEF{T}                  # Earth-Centered, Earth-Fixed (x, y, z)
│   └── UTM{T}                   # Universal Transverse Mercator
└── AbstractRelativeCoords{T}    # require a reference point
    ├── ENU{T}                   # East, North, Up
    ├── NED{T}                   # North, East, Down
    └── AER{T}                   # Azimuth, Elevation, Range

All geodetic operations accept any AbstractFixedCoords. Relative coordinate types require a reference LLA point for conversion.