greiner-hormann-typescript

Greiner-Hormann polygon clipping (TypeScript port)

This is the TypeScript port of the original package w8r/GreinerHormann

• Does AND, OR, XOR (intersection, union, difference, if you're human)
• Plays nicely with Leaflet, comes with an adaptor for it
• Handles non-convex polygons and multiple clipping areas
• ~5kb compressed, no dependencies

Original demo and documentation

New test and demo

Note: If you are looking for something more powerful, take a look at the Martinez polygon clipping implementation.

Install

$ npm install greiner-hormann-typescript

Browserify

var greinerHormann = require('greiner-hormann-typescript');

Browser

<script src="path/to/greiner-hormann-typescript(.leaflet).min.js"></script>

Use

...
const intersection : Array<Array<IVertex>> = greinerHormann.intersection(source, clip);
const union : Array<Array<IVertex>>        = greinerHormann.union(source, clip);
const diff : Array<Array<IVertex>>         = greinerHormann.diff(source, clip);

...

if(intersection){
    if(typeof intersection[0][0] === 'number'){ // single linear ring
        intersection = [intersection];
    }
    for(var i = 0, len = intersection.length; i < len; i++) {
        L.polygon(intersection[i], {...}).addTo(map);
    }
}

Format

Input and output can be {x:x, y:y} objects or [x,y] pairs. It will output the points in the same format you put in.