point-in-polygon

Kishan J: This is a modified fork of James Halliday's point-in-polygon and includes alternative algorithms beyond ray casting because the original library does not include points on boundaries (see issue#2) by adding a third optional param to the main function (see Usage).

Determine if a point is inside of a polygon.

This module casts a ray from the inquiry point and counts intersections, based on this algorithm.

Install

npm install @kishannareshpal/point-in-polygon

Example

const inside = require('point-in-polygon');
const polygon = [ [ 1, 1 ], [ 1, 2 ], [ 2, 2 ], [ 2, 1 ] ];

console.dir([
    inside([ 1.5, 1.5 ], polygon),
    inside([ 4.9, 1.2 ], polygon),
    inside([ 1.8, 1.1 ], polygon)
]);

output:

[ true, false, true ]

Usage

const inside = require('point-in-polygon')

// inside(point, polygon, includeAllEdges)

Return whether point is contained in polygon. point should be a 2-item array of coordinates. polygon should be an array of 2-item arrays of coordinates. A 2d Array. includeAllEdges should be true if you want to return true for all edges, otherwise false. See issue#2.

Contributing

Bug Reports & Feature Requests

Please use the issue tracker to report any bugs or file feature requests.

Developing

PRs are welcome. To begin developing, do this:

$ git clone [email protected]:kishannareshpal/point-in-polygon.git
$ cd point-in-polygon/
$ npm install

# Run tests
$ npm test

Credit

Thanks James Halliday's for his original work on this package point-in-polygon,

License

The MIT License (MIT)

Copyright (c) 2016 James Halliday

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.