Number#snap Useful JavaScript Game Extension #25

Well my friends, it’s been quite some time. So without further ado back to the series!

/**
 * Returns the the nearest grid resolution less than or equal to the number.
 *
 *   EX:
 *    (7).snap(8) => 0
 *    (4).snap(8) => 0
 *    (12).snap(8) => 8
 *
 * @param {Number} resolution The grid resolution to snap to.
 * @returns The nearest multiple of resolution lower than the number.
 * @type Number
 */
Number.prototype.snap = function(resolution) {
  return (this / resolution).floor() * resolution;
};

This handy method is useful for when you need to snap input to a grid (like in a tile editor).

I hope you enjoyed this installment of the wonderful 256 part series on JavaScript game extensions.

Author: Daniel X

Heretic priest of the Machine God. I enjoy crawling around in Jeff Bezo's spaceship, bringing technology to the people, and long walks outside of time and space. View all posts by Daniel X