====== Box (add-on format) ======

Sometimes it is necessary to combine multiple addons into a single 'mod' package for distribution. A mod consisting of multiple [[#Components|components]] (perhaps by different authors) can be packaged together into a single folder.

The **.box** format was initially created for the Snowberry launcher app. Recent versions of Doomsday support it, too.

In Doomsday 2, [[packages]] can be set up to contain other packages.


===== Overview =====


The **.box** format is a special [[modding:addon format]], allowing several addons to be collected together. The box itself contains no data, only [[#Metadata|metadata]]. All data within the box is contained in separate [[#Components|components]].

This separation of metadata from addon-data provides several benefits:
  *  Allows components to be combined dynamically
  *  Allows the user (via a GUI) to customize components and to drill down to the information of a specific component (e.g., determining the author of your favorite map)
  *  Keeps everything nice and clean


===== Anatomy =====


The high-level structure of a **.box** is as follows:
  
  collection.box /
  | Info
  | part1.pk3
  | part2.pk3
  | required /
    | part3.pk3
  | extra /
    | part4.wad
  |...


<note>Unlike in [[modding:addon bundle]]s, there is no **Contents/** subfolder. This is intended to highlight the fact that the box itself contains no data: it is merely a group of other addons.</note>


==== Metadata ====

[[modding:Info]] is a plain text file — note the lack of extension in the name — which describes the contents of the box (i.e., metadata). This is analogous to the use of [[modding:Info]] in [[modding:addon bundle]]s.


==== Components ====

A box may contain multiple sub-component addons. For example, a box might comprise two required [[PK3]]s, an optional [[DED]], and one [[WAD]] file. The only restriction is that a box cannot contain other boxes. 


=== Optional ===

Addons in the root are optional. They will be loaded by default along with the box itself.


=== Extra ===

The **extra/** folder should contain addons that that are optional but which are //not// active by default. These components must be activated manually before use, for instance by checking on a checkbox in the GUI.


=== Required ===

The **required/** folder should contain addons that are //always// loaded when the box itself is loaded. These components won't even be visible to the user.

Snowberry automatically categorizes all addons inside the box according to their type and/or contents and all are visible to the user (except those which are under [[#Required|Required]]) in the addon tree.


===== Example =====


First you'll need an [[modding:Info]] file which describes this collection of add-ons. Something like:
  
  name: Amaze-DOOM
  component: game-jdoom
  
  language english (
    version: 6.01
    summary: Amazing TC (trust me)
    contact: http://www.moddingworld.com
    author: Mod-O-tron-2000
  
    copyright: 2015
    license: Do what you will, I don't care
  
    readme = "Amaze-DOOM TC
    Look, just play it, damn it!"
  )


Now create a folder and give it a name of your choosing with a **.box** suffix. Place here the info file and required subcomponents like so:
  
  amazedoom.box /
   | info          - (the 'global' info file)
   | required /
     | episode1.pk3
     | episode2.pk3
   | ...


Congrats! You now have a multi-component add-on bundle.