Bin Pack

A packing algorithm for 2D bin packing. Largely based on code and a blog post by Jake Gordon.

This library packs objects that have a width and a height into as small of a square as possible, using a binary tree bin packing algorithm. After packing, each object is given an (x, y) coordinate of where it would be optimally packed.

The algorithm may not find the optimal bin packing, but it should do pretty will for things like sprite maps.

Installation

npm install bin-pack

Use

var pack = require('bin-pack');
var bins = [
	{ width: 10,  height: 20 },
	{ width: 100, height: 100 },
	{ width: 50,  height: 19 },
	...
	];

var result = pack(bins);

// result.width: width of the containing box
// result.height: height of the containing box
// result.items: packed items
// result.items[0].x: x coordinate of the packed box
// result.items[0].y: y coordinate of the packed box
// result.items[0].width: width of the packed box
// result.items[0].height: height of the packed box
// result.items[0].item: original object that was passed in

If your object doesn't have x and y properties, and you don't mind a library writing to your objects, then specify inPlace: true and your objects will have a x and y properties added to them.

var pack = require('bin-pack');
var bins = [
	{ width: 10,  height: 20 },
	{ width: 100, height: 100 },
	{ width: 50,  height: 19 },
	...
	];

var result = pack(bins, { inPlace: true });
// result.width: width of the containing box
// result.height: height of the containing box
// bins[0].x: x coordinate of the packed box
// bins[0].y: y coordinate of the packed box

Contributing

Contributing tests, documentation, or code is all appreciated. All code should be accompanied by valid tests.