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Sometimes it is necessary to make a collection of multiple addons. For example, your addon might be composed of two required PK3s, an optional PK3, and a WAD file.
Snowberry supports a special addon format called a Box, where several normal addons (addon bundle, PK3, WAD, etc.) are collected together. Boxes cannot contain other boxes. The Box itself contains nothing but metadata (e.g., name and version number). All the data of a box addon is contained within the "parts" of the box, i.e., the addons inside the box.
The structure of a Box is described below:
collection.box/ Info part1.pk3 part2.pk3 Required/ part3.pk3 Extra/ part4.wad
Note that unlike in bundles, there is no =Contents= subfolder. This is intended to highlight the fact that a box itself contains no data: it is merely a group of other addons.
The Info file is a text file that contains information about the box. This is similar to the Info file in bundles.
Addons in the root of the .box folder are optional, but they will be selected by default, if the box is selected for loading. The Required subfolder contains all the addons that are always loaded when the box is loaded. These addons won't even appear in the addons tree. The Extra subfolder contains addons that are optional and not selected by default. The user must select them manually if he wishes to use them. All the addons inside the box, except the required ones, are visible in the addons tree on the Addons tab.
Addons inside the box are assigned to their own category. See the example box in the SVN repository. An example of a .box can be found in the [[1][Snowberry CVS]].