A tiny library for packing 2D rectangles (for sprite layouts)

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1.0.210 months ago4 years agoMinified + gzip package size for potpack in KB


A tiny JavaScript library for packing 2D rectangles into a near-square container, which is useful for generating CSS sprites and WebGL textures. Similar to shelf-pack, but static (you can't add items once a layout is generated), and aims for maximal space utilization.
A variation of algorithms used in rectpack2D and bin-pack, which are in turn based on this article by Blackpawn.


Example usage

import potpack from 'potpack';

const boxes = [
    {w: 300, h: 50},
    {w: 100, h: 200},

const {w, h, fill} = potpack(boxes);
// w and h are resulting container's width and height;
// fill is the space utilization value (0 to 1), higher is better

// potpack mutates the boxes array: it's sorted by height,
// and box objects are augmented with x, y coordinates:
boxes[0]; // {w: 300, h: 50,  x: 100, y: 0}
boxes[1]; // {w: 100, h: 200, x: 0,   y: 0}


Install with NPM (npm install potpack) or Yarn (yarn add potpack), then:
// import as an ES module
import potpack from 'potpack';

// or require in Node / Browserify
const potpack = require('potpack');

Or use a browser build directly:
<script src="https://unpkg.com/potpack@1.0.1/index.js"></script>