A sound pack can be installed in the data/sound directory. data/sound/soundset.json contains a list of sound effects in the following format.

{
    "sound_effects" : [
        {
            "id" : "<sfx-id>",
            "variant" : "<sfx-variant>",
            "volume" : <volume>,
            "file" : "<file-name>"
        },
        ...
    ]
}

Each sound effect is identified by an id and a variant. If a sound effect is played with a variant that does not exist in the soundset.json file, but a variant "default" exists, then the "default" variant is played instead. The file name of the sound effect is relative to the data/sound directory, so if the file name is set to "sfx.wav", the file must be placed at `data/sound/sfx.wav`.

A full list of sound effect id's and variants is given in the following. Each line in the list has the following format:

id variant1|variant2

Where id describes the id of the sound effect, and a list of variants separated by | follows. When the variants are omitted, the variant "default" is assumed. Where the variants do not represent literal strings, but variables, they will be enclosed in < >. For instance, <furniture> is a placeholder for any valid furniture ID (as in the furniture definition JSON).

footstep default|light|clumsy|bionic
explosion default|small|huge
open_door <furniture>|<terrain>
close_door <furniture>|<terrain>
bash default
smash wall|door|door_boarded|glass
melee_hit <weapon> # note: use weapon id "null" for unarmed attacks
fire_gun <weapon>
reload <weapon>