declare empty 2d array of size m * n in JS code example

Example 1: javscript generate empty 2d array

var grid = [...Array(width)].map(e => Array(height));
// access via grid[y][x]

Example 2: create 2d array in javascript filled with 0

function zeros(dimensions) {
    var array = [];

    for (var i = 0; i < dimensions[0]; ++i) {
        array.push(dimensions.length == 1 ? 0 : zeros(dimensions.slice(1)));
    }

    return array;
}

> zeros([5, 3]);
  [[0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0]]