geo-intersection-util

A lightweight TypeScript/JavaScript utility for calculating the perpendicular intersection of a point (e.g., a golf shot or geographic location) to a given centerline path. Supports distance and directional analysis (left/right/center) and works in both frontend and backend environments.

✨ Features

• Compute perpendicular intersection from a geographic point to a path
• Get distance (in meters) and side (left/right/center)
• Accepts centerline in "lng lat" string format
• Pure TypeScript with JS compatibility
• Lightweight, no external dependencies

Installation

npm install geo-intersection-util

🚀 Quick Start

TypeScript

import { Intersection } from "geo-intersection-util";

const center =
  "88.426709 22.579435, 88.430032 22.581458, 88.432886 22.582901, 88.437578 22.580801";
const point = "88.433217 22.581856";
const forward = "88.438367 22.580495";

const intersection = new Intersection();
const result = intersection.getInterSection(center, point, forward);

console.log(result);

JavaScript

const { Intersection } = require("geo-intersection-util");

const center =
  "88.426709 22.579435, 88.430032 22.581458, 88.432886 22.582901, 88.437578 22.580801";
const point = "88.433217 22.581856";
const forward = "88.438367 22.580495";

const intersection = new Intersection();
const result = intersection.getInterSection(center, point, forward);

console.log(result);

🧩 API Reference

getInterSection(centerLine: string, point: string, forwardPoint: string): IntersectionResult | undefined

Returns the intersection point on the centerline, the distance from the given point to the centerline (in meters), and the side relative to the centerline.

Parameters

• centerLine (string): A comma-separated string of "lng lat" pairs representing the path.
• point (string): The shot or location point in "lng lat" format.
• forwardPoint (string): A "lng lat" point to help orient the centerline.

Return

{
  intersectionLatLng: { lat: number; lng: number };
  distance: number; // in meters
  side: "left" | "right" | "center" | null;
}

📐 Units

• Distance is returned in meters.
• You can convert it to yards: yards = meters * 1.09361

🧪 Example Use Case

Perfect for:

• Golf shot dispersion analysis
• Road/path mapping
• Navigation systems
• GIS-based tools

📝 License

MIT © 2025 Mayank Anand

📬 Author & Support

Mayank Anand
Email: [email protected]

Contributing

💡 Have suggestions? I'm always open to feedback! Feel free to write to me or submit a request to improve accuracy or add new features.