Wet System - Custom Decorative Objects

WET System Framework is a modding framework for Subnautica 2 that allows anyone to add custom decorative objects and meshes to the game without writing code.

Using simple .wet.json files placed in the ~mods folder, modders can create new placeable decorations that automatically appear in a dedicated in-game menu (UI is WIP).

Installation

You need UE4SS

Place "WetSystem" inside: Subnautica2\Subnautica2\Content\Paks\LogicMods
Place "WetScript" inside: Subnautica2\Subnautica2\Binaries\Win64\ue4ss\Mods

Be careful to have "WetScript : 1" (if not add it) inside ue4ss\Mods\mods.txt

If, in the menu, you see "Wet System" below the logo, that's good!

In-Game Placement Menu

Press F9 to open the WET Framework object menu.

From there, you can browse and place any registered custom object.

Controls

Current controls:

Left Click – Place object
F – Move selected object
X – Remove selected object
Top/Down Arrow – Change select object to place
Left/Right Arrow – Change Variant of the selected object (if available)

Features

Custom Decorative Objects

Create new decorative items by defining them in a .wet.json file.

Supported features include:

Custom meshes
Custom thumbnails (UI is WIP)
Categories
Placement settings
Custom transforms
Surface snapping
Multiple appearance variants

Multiplayer has not been tested yet.

Planned Features

Short Term

Placeable blueprints
Interactive objects (lights, switches, etc.)
Objects with inventories (storage containers and similar)

Long Term

Integration with the in-game constructor (if technically possible)
No longer use UE4SS
Custom foundations
Custom vehicles

For Mod Authors
Creating Custom Objects

Objects are defined through .wet.json files placed inside the ~mods directory.

A basic object can define:

Name
Description
Category
Mesh
Thumbnail
Transform settings
Placement behavior

bedsideTable.wet.json:

{
  "id": "wet_cozy_bedside_table",
  "version": "1.0.0",

  "category": "Furniture",
  "name": "Bedside Table",
  "description": "A wooden bedside table",

  "staticMesh": "/Game/Mods/WetCozyPack/BedsideTable/SM_Bedside_Table.SM_Bedside_Table",

  "thumbnail": "/Game/Mods/WetCozyPack/BedsideTable/TX_Bedside_Table_Thumb.TX_Bedside_Table_Thumb",

  "transform": {
    "scale":    { "x": 1.0,  "y": 1.0,  "z": 1.0 },
    "offset":   { "x": 0.0,  "y": 0.0,  "z": 0.0 },
    "rotation": { "pitch": 0.0, "yaw": 0.0, "roll": 0.0 }
  },

  "placement": {
    "snapping": "surface",
    "boxExtents": { "x": 35.0, "y": 4.0, "z": 55.0 },
    "allowedSurfaces": 7,
    "interactDistance": 350.0
  },
}

Variant Support

Objects can contain multiple variants.

Variants allow a single object entry to provide multiple appearances, meshes, or material combinations.

While placing an object, use the Left Arrow and Right Arrow keys to cycle through available variants.

Examples:

Multiple poster designs
Different furniture styles
Alternate material presets
Color variations

{
  "id": "wet_poster",
  "name": "Poster Frame",
  "description": "A decorative poster for your base.",
  "category": "Posters",

  "thumbnail": "/Game/Utility/Editor/IconBaker/IconTextures/IconBaker_BasePieces/T_PowerGridCapacitor_Icon.T_PowerGridCapacitor_Icon",

  "transform": {
    "scale": { "x": 1.0, "y": 1.0, "z": 1.0 }
  },

  "placement": {
    "_comment_snapping": "surface = snap to any surface.  Freeform = float in front of camera.",
    "snapping": "surface",
    "_comment_boxExtents": "Half-extents in cm: x=half-width  y=half-depth (into wall)  z=half-height.",
    "boxExtents": { "x": 35.0, "y": 4.0, "z": 55.0 },
    "_comment_allowedSurfaces": "Bitmask: 1=floor  2=wall  4=ceiling  7=all.",
    "allowedSurfaces": 7,
    "interactDistance": 350.0
  },

  "isLocked": false,

  "_comment_variants": "Each entry is a selectable appearance for this item. Switch with Left/Right arrow keys while placing. Only variantName, staticMesh, and materials are variant-specific; everything else (placement, transform, category) is shared.",
  "variants": [
    {
      "variantName": "Empty Frame",
      "staticMesh": "/Game/Art/Items/Posterframe/Mesh/SM_PosterFrame_01_Vertical_A.SM_PosterFrame_01_Vertical_A"
    },
    {
      "variantName": "Keep Calm",
      "staticMesh": "/Game/Art/Items/Posterframe/Mesh/SM_PosterFrame_01_Vertical_A.SM_PosterFrame_01_Vertical_A",
      "materials": [
        null,
        null,
        null,
        "/Game/Art/Environment/Set/Alterra/Props/Posters/Materials/MI_Alterra_PosterKitty_01a.MI_Alterra_PosterKitty_01a"
      ]
    }
  ]
}

Notes

This framework is currently focused on decorative objects.

Interactive gameplay functionality is still under development and will be expanded in future releases.

Feedback, bug reports, and example object packs are always welcome.

There is no danger for save file!

License

This project is proprietary software.

Usage is permitted for personal gameplay and for creating content packs compatible with the framework.

Modification, redistribution, reverse engineering, or reuse of the framework code is prohibited without explicit permission from the author.

Wet System Framework