Simple run length encoding library

npm install voxel-crunch
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This library applies run length encoding to an array of octets, and returns the result. It can be used to compress individual chunks in voxel.js, or more generally any array of ints.

Though this is designed to work with voxel.js, the code in this library is sufficiently generic that it can run length encode any int-like array.


Via npm:

npm install voxel-crunch


var data = chunk.voxels
//First encode data
var rle = require("voxel-crunch").encode(data)
//Then decode
var result = require("voxel-crunch").decode(rle, new Uint32Array(data.length))
//    result == data


Counts the number of bytes required to run length encode chunk

  • chunk is the chunk to be encoded

Returns A number representing the minimal number of bytes necessary to compress chunk

Returns The number of runs required to compress the chunk

require("voxel-crunch").encode(chunk[, result])

Run length encodes an array of int-like objects

  • chunk is either an array-like object
  • result is an optional array argument which stores the result of the encoding. If not specified, a Uint8Array is allocated.

Returns If result is specified, then result is returned. Otherwise a new array is allocated.

Throws An error if the result buffer is too small

require("voxel-crunch").decode(runs, result)

This method decodes a crunched chunk back into a full chunk. It takes 3 arguments:

  • runs is the crunched chunk
  • result is an array which gets the result of unpacking the voxels

If the runs are not valid or if the bounds on the chunk are exceeded, an error will be thrown.

Returns result

Throws An error if either result is too small or runs is invalid.


(c) 2013 Mikola Lysenko. BSD

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