# Modding

Modding support in Helium Rain is coming ! As of today, it's not officially released. This guide will be applicable when it is.

## Overview

• Helium Rain mods will be distributed through Steamworks.
• Modding will require the Helium Rain Mod Kit, available through the Epic Games Launcher for free. No other software is required. The Helium Rain Mod Kit doesn't provide all game assets, though about half of them are provided for reference.
• Mods in Helium Rain can enable new ships, stations, resources, sectors, or ship upgrades.
• Mods cannot add new quests, story, or new C++ functionality.
• Mods are provided at your own risks - removing a mod will very likely crash your save, etc.
• The modding SDK requires 50GB of available space.

## Creating a mod

To start the modding process, you will need to download the Epic Games Launcher, register, and open the Modding tab. Download the Helium Rain Mod Kit, and you're ready to go ! Make sure you know where the mod kit is installed on your computer, as you will be working from there to set it up. The modding SDK should have two folders - one named "UE_4.20", which is the engine, and one named "HeliumRainModKit" - everything will happen in the second folder.

Modding will work by creating a plugin for the game. We'll create a mod named ExampleMod for reference - make sure to always use the same name everywhere, without spaces or special characters. A copy of this mod exists in the HeliumRainModKit folder.

A plugin has to be created in the /Mods folder of the SDK, and has three mandatory components :

• A plugin file, ExampleMod.uplugin, created manually
• A preview image for Steamworks, Preview.png, created manually
• A content directory, that will be created through the editor

The syntax of the plugin file is quite easy. Here is an example.

   {
"FileVersion" : 3,

"FriendlyName" : "Example Mod",
"Version" : 1,
"VersionName" : "1.0",
"CreatedBy" : "Deimos Games",
"CreatedByURL" : "http://helium-rain.com",
"EngineVersion" : "4.20.0",
"Description" : "Example mod for the Helium Rain Mod Kit",
"Category" : "User Mod",
"EnabledByDefault" : true,
"Modules" :
[
],
"CanContainContent" : true
}


Once this is done, you can launch the Unreal Engine editor right away. You don't need to decide on a great description or a kick-ass preview - you can edit both later and update the mod on Steam.

## Creating content

This part assumes you are familiar with Unreal Engine 4. We won't provide our own guide, or detailed guides on how the game assets are structured.

• All of our gameplay data is created through what we call DataAssets. You can find many of them in the /Gameplay/Catalog folder of the Content Browser as examples - look at how they're built, and learn from that.
• Ships or stations have an additional Templatefile, built with UE4's Blueprint tool. Templates let us actually design the ship and place parts. These are found in /Ships/Templates and /Stations/Templates, and are referenced from the DataAssets.
• A new ship would require both a new data asset and a new template. A modified ship could only use a new data asset, and keep the base template.
• A new weapon or engine would require a data asset and a StaticMesh.
• New sectors only require a data asset, but can also feature an entire new level, if you add a sub-level to the Space map, and provide its name in the data asset.

Talk with other modders on the Steam forums, or our Reddit forum, to get answers ! The source code for the game is also available - see below.

## Building a mod

To build a mod, you will need to open the Project Launcher window in Unreal Engine (view / , and ). Add a new profile using the small "plus" sign on the bottom right, or use the provided "Mod" profile.

We will create a profile that "cooks" a "Shipping" "DLC", using a "PAK file" with compression, based on a previous release of the game. Let's explain all of this.

• Cooking is the process to create a usable mod file for a packaged game. This file will be a .pak file, a compressed archive of your mod.
• Like the following picture, make sure you pick the "HeliumRain" project by browsing for the HeliumRain.uproject file.
• We will cook for WindowsNoEditor, and LinuxNoEditor. Please cook for the "en" culture.
• What is called DLC here is your mod - use the name of your own mod.
• The release is the name of the folder inside /Releases/ - currently "1.3.2".

Once you have filled the details in, run the profile. This will be required for every content update.

   Boiler --game HeliumRain --mod ExampleMod