@math.gl/polygon

What is @math.gl/polygon?

@math.gl/polygon is a JavaScript library for performing geometric operations on polygons. It is part of the math.gl suite, which provides high-precision mathematical operations for geospatial applications. This package is particularly useful for tasks such as polygon clipping, triangulation, and point-in-polygon tests.

What are @math.gl/polygon's main functionalities?

Polygon Clipping

This feature allows you to clip one polygon with another, effectively finding the intersection area between the two polygons.

const {clipPolygon} = require('@math.gl/polygon');
const subjectPolygon = [[0, 0], [10, 0], [10, 10], [0, 10]];
const clipPolygon = [[5, 5], [15, 5], [15, 15], [5, 15]];
const result = clipPolygon(subjectPolygon, clipPolygon);
console.log(result);

Triangulation

This feature breaks down a polygon into a set of triangles, which can be useful for rendering or computational geometry tasks.

const {triangulate} = require('@math.gl/polygon');
const polygon = [[0, 0], [10, 0], [10, 10], [0, 10]];
const triangles = triangulate(polygon);
console.log(triangles);

Point-in-Polygon Test

This feature checks whether a given point lies inside a polygon, which is useful for hit-testing and spatial queries.

const {isPointInPolygon} = require('@math.gl/polygon');
const polygon = [[0, 0], [10, 0], [10, 10], [0, 10]];
const point = [5, 5];
const isInside = isPointInPolygon(point, polygon);
console.log(isInside);

Other packages similar to @math.gl/polygon

turf

Turf is a comprehensive geospatial analysis library for JavaScript. It offers a wide range of functionalities including polygon operations, distance calculations, and spatial analysis. Compared to @math.gl/polygon, Turf provides a broader set of geospatial tools but may be more complex to use for simple polygon operations.

polygon-clipping

Polygon Clipping is a library focused specifically on polygon clipping operations. It is highly optimized for performance and can handle complex polygon intersections. While it offers similar clipping functionalities as @math.gl/polygon, it does not provide other features like triangulation or point-in-polygon tests.

earcut

Earcut is a fast and robust library for polygon triangulation. It is widely used in graphics applications for breaking down complex polygons into triangles. Compared to @math.gl/polygon, Earcut is specialized in triangulation and does not offer other polygon operations.

README

@math.gl/polygon

math.gl is a suite of math modules for 3D applications.

This module contains utilities that work with polylines and polygons.

For documentation please visit the website.

Changelog

v3.2.0-alpha.3 - May 14, 2020

• [web-mercator] Add getBounds utility (#146)
• Fix the bounds type for FitBoundsOptions (#149)
• fix build script (#148)
• Refactor WebMercatorViewport (#145)
• Clean up bounding volume classes and docs (#144)
• Fix web mercator projection far plane at high pitch (#142)
• Restore default export of @math.gl/web-mercator (#141)