Usage no npm install needed!

<script type="module">
  import gridNeighbors1d from 'https://cdn.skypack.dev/grid-neighbors-1d';
</script>

README

grid-neighbors-1d

Get the 8 closest neighbors of a grid with edge wrapping from a 1d array

Why?

grid-neighbors

Usage

Get the neighbors of cell 12 in a 5x6 grid:

const gn = require('grid-neighbors-1d');
const neighbors = gn(12, 5, 6);
console.log(neighbors); // [7, 8, 13, 18, 17, 16, 11, 6] - clockwise from north

grid-neighbors returns an 0-based array of indexes of the cell immediately to the north of the chosen cell, then clockwise around the remaining cells:

neighbors[0] = north neighbor
neighbors[1] = north east neighbor
neighbors[2] = east neighbor
neighbors[3] = south east neighbor
neighbors[4] = south neighbor
neighbors[5] = south west neighbor
neighbors[6] = west neighbor
neighbors[7] = north west neighbor

License

Shared under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported license.