Modding support in Helium Rain is currently a work in progress. Information written here may change. The following guide is meant for Windows users ; Linux modders might need more efforts.
Creating your modding environment (Windows)
Installing a modding SDK for Helium Rain requires a few steps: getting Unreal Engine 4, installing the required tools, downloading the game sources, and downloading the game content kit.
Getting Unreal Engine 4
Helium Rain uses UE4 as a game engine. You can get it for free at unrealengine.com. You will need to sign up and download the Epic Games launcher.
In the launcher library for Unreal Engine, install version 4.16.3.
Installing the tools
You will need the following tools to build Helium Rain from the sources:
- Visual Studio Community 2017 will be used to build the sources: https://www.visualstudio.com/downloads/ . Don't forget to select the C++ development environment, since this is optional.
- The Windows 8.1 SDK is required for Unreal Engine 4: https://developer.microsoft.com/en-us/windows/downloads/windows-8-1-sdk .
- The DirectX SDK is required for the joystick plugin: https://www.microsoft.com/en-us/download/details.aspx?id=6812 .
- CMake is required for the joystick plugin: https://cmake.org/download . When prompted to add to the system PATH, please do it.
- TortoiseHg is required for the joystick plugin: https://tortoisehg.bitbucket.io/ .
Getting the Helium Rain source code
Go to the Helium Rain repository on GitHub and select the release branch. Use the "clone or download" button to get the sources. If you are familiar with Git, you should probably use it to clone the sources, but downloading a zip archive works too.
You will also need a content archive to install in the game. This will be provided once an official workflow is available.
Building the game from sources
We will now build the Helium Rain editor from the sources. Follow these steps.
- Open a Windows console (Windows + R ; "cmd" ; Enter).
- Navigate to the Plugins\JoystickPlugin\ThirdParty\SDL2 folder in the Helium Rain archive.
- Run setup.bat and wait for it to complete without errors.
- Run build.bat and wait for it to complete without errors.
- In the Windows explorer, right-click HeliumRain.uproject and pick "Generate Visual Studio Project Files".
- A HeliumRain.sln file will appear - double-click it to open Visual Studio.
- You can now build Helium Rain by hitting F7 or using the Build menu. This should take from 5 to 10 minutes.
Once the process is done, you can launch Unreal Engine by double-clicking the HeliumRain.uproject file. The editor should open after a few minutes - around the same time as compiling.
Creating mod content
The modding process is yet to be documented. We will update this guide once an official workflow is available.