Module geospatial 

Geospatial functionality for working with geographic coordinates

This module provides basic geospatial operations including:

• Coordinate system transformations
• Great circle distance calculations (Haversine formula)
• Bearing and azimuth calculations
• Geodesic operations on the sphere

Coordinate Systems

The module supports common geographic coordinate systems:

• WGS84: World Geodetic System 1984 (GPS standard)
• Geographic: Latitude/Longitude coordinates
• UTM: Universal Transverse Mercator projections
• Web Mercator: Spherical Mercator (EPSG:3857)

Examples

use scirs2_spatial::geospatial::{haversine_distance, initial_bearing, destination_point};

// Calculate distance between two cities
let london = (51.5074, -0.1278);  // Latitude, Longitude
let paris = (48.8566, 2.3522);

let distance = haversine_distance(london, paris);
println!("Distance from London to Paris: {:.1} km", distance / 1000.0);

// Calculate bearing
let bearing = initial_bearing(london, paris);
println!("Initial bearing: {:.1}°", bearing.to_degrees());

// Find destination point
let destination = destination_point(london, 100000.0, bearing); // 100 km
println!("100km from London: ({:.4}, {:.4})", destination.0, destination.1);

Constants

EARTH_ECCENTRICITY_SQ

Earth’s eccentricity squared (WGS84)

EARTH_EQUATORIAL_RADIUS_M

Earth’s equatorial radius in meters (WGS84)

EARTH_FLATTENING

Earth’s flattening (WGS84)

EARTH_POLAR_RADIUS_M

Earth’s polar radius in meters (WGS84)

EARTH_RADIUS_KM

Earth radius in kilometers

EARTH_RADIUS_M

Earth radius in meters (WGS84 mean radius)

Functions

along_track_distance

Calculate the along-track distance (distance along a great circle path to the closest point)

cross_track_distance

Calculate the cross-track distance (distance from a point to a great circle path)

deg_to_rad

Convert degrees to radians

destination_point

Calculate the destination point given a starting point, distance, and bearing

final_bearing

Calculate the final bearing (back azimuth) when arriving at point2 from point1

geographic_to_utm

Convert geographic coordinates to UTM coordinates

geographic_to_web_mercator

Convert geographic coordinates to Web Mercator (EPSG:3857)

haversine_distance

Calculate the great circle distance between two points using the Haversine formula

initial_bearing

Calculate the initial bearing (forward azimuth) from point1 to point2

midpoint

Calculate the midpoint between two geographic points

normalize_angle

Normalize angle to [0, 2π) range

normalize_bearing

Normalize bearing to [0°, 360°) range

point_in_spherical_polygon

Check if a point is inside a spherical polygon using the winding number method

rad_to_deg

Convert radians to degrees

spherical_polygon_area

Calculate the area of a polygon on the sphere using spherical excess

vincenty_distance

Calculate the vincenty distance between two points (more accurate than Haversine)

web_mercator_to_geographic

Convert Web Mercator coordinates to geographic coordinates