Lambda1VR is a port / mod of the Xash3D-FWGS Half-Life Engine for the Oculus Quest adding 6DoF weapon support and OpenGLES2.0 rendering.

Xash3D is a game engine, aimed to provide compatibility with Half-Life Engine, 
as well as to give game developers well known workflow and extend it.
Read more about Xash3D on ModDB: https://www.moddb.com/engines/xash3d-engine

The easiest way to install this on your Quest is using SideQuest, a PC desktop app designed to simplify sideloading apps and games ( even beat saber songs on quest ) on Standalone Android Headsets like Oculus Quest and Oculus Go. It supports drag and drop for installing APK files!

Download the latest version of SideQuest here: https://github.com/the-expanse/SideQuest/releases

Once you have installed Lambda1VR you will need to copy the game assets from a legally owned half-life install. Details below.

This is solely an engine port/mod, no game assets are included whatsoever. YOU MUST LEGALLY OWN HALF-LIFE IF YOU WISH TO PLAY IT IN VR USING LAMBDA1VR.

The original half-life can be purchased on Steam: https://store.steampowered.com/app/70/HalfLife/

PLEASE NOTE: Half-life: Source is not compatible.

Before attempting to start Lambda1VR you need to do the following:

• Create a folder on your Quest called "xash"
• Locate the install of half-life on your PC, if installed from Steam then it will be somewhere like C:/Program Files (x86)/Steam/steamApps/common/HalfLife/
• Copy the entire folder "valve" to the newly created "xash" folder on the Quest (This will take a long time)
• (optional) Copy the contents of the valve_hd folder into the valve folder now on your Quest (this gives you some nicer models). If you are a Mac user please read this post, otherwise you will get a crash: https://www.reddit.com/r/Lambda1VR/comments/cls57m/mac_running_halflife_with_hd_assets_on_quest/

Save game files are stored on the internal memory of your quest in the xash/valve folder. This means that if you uninstall/reinstall Lambda1VR all the saves are retained. If you change headset just make sure you copy {quest}/xash/valve/save to the new Quest.

Before you ask... YES!, the crowbar has to be swung in real life to smash stuff! (except in multi-player, you still have to press the trigger I'm afraid).

add the following cvar to your config.cfg file: hand "1"

* Weapon stabilisation has a deadzone when the two controllers are less than 15cm from each other to prevent screwing up aiming with the Glock etc

• Your screen name (for multi-player) can be set in the config.cfg file
• FPS counter can be enabled in the Video Options menu
• Weapon recoil is disabled by default.. if you want a more authentic experience it can be enabled with the cvar: vr_weapon_recoil 1
• If the player height is messed up. Try reseting the view by holding the home button for 2 seconds. After that go into the main menu and back into the game.
• After changing files in xash/vale folder, often the device needs to be restarted for the game to use the changed files.

Hopefully there will be fixes in time for most of the following, but rather than delay release any longer, none of could be considered show-stoppers:

• After a load or transition the crowbar and some other weapons' position is not located at the right controller, change weapon and then back again to resolve - I am looking into this and hope to fix it in a future update
• Application crashes when you complete the Hazard Course
• RPG (and some other weapons) laser-targetting is based on head orientation
• No way to enter text at the moment
• Positional tracking doesn't really work on multi-player servers (unless you run your own server and set the following cvar: sv_accelerate 10000), it sort of works if you hold down the "run" trigger, but it isn't very good
• Lambda1VR will crash if you haven't copied the half-life game assets to the right location, no warning, just crash
• Complaint when you exit that the app did not shutdown properly (or crashed or something).. since you are quitting this wasn't considered serious enough to hold up the release, but will be fixed in a future update

• Text entry / Virtual Keyboard - Frustratingly the Quest virtual keyboard isn't available through the native SDK :(
• Add a flashlight model for the left hand when not stabilising a weapon
• Better grenade throwing mechanics (pretty janky at the moment)

You need the following:

• Android Developer Studio
• Android SDK API level 24
• Latest Android Native Development Kit
• Oculus Mobile SDK 1.24.0
• The Lambda1VR folder should be below VrSamples in the extracted SDK
• Create a local.properties file in the root of the extracted Oculus Mobile SDK that contains the ndk.dir and sdk.dir properties for where your SDK/NDK are located (see Gradle documentation regarding this)
• To build debug you will need a android.debug.keystore file placed in the following folder: oculus_sdk_dir/VrSamples/Lambda1VR/Projects/Android

Alternatively you can use the docker image created by BrainSlugs83 which can be found here: https://github.com/BrainSlugs83/DockerOvrSdk

I would like to thank the following teams and individual for making this possible:

• Baggyg - My long-time VR friend whose roles in this have been varied and all helpful, also the creator of excellent websites/artwork/assets for this mod
• The Xash3D team
• GLE4ES without which this wouldn't have worked at all: https://github.com/ptitSeb/gl4es
• Max Vollmer for their 2017 Half-Life VR mod, of which I used and modified the 6DoF weapons code for this mod, the original code for which can be seen here: https://github.com/maxvollmer/Half-Life-VR
• The SideQuest team - For making it easy for people to install this
• https://github.com/formicsapien for the weapon models that work much better with 6DoF

Lambda1VR is not affiliated, associated, authorized, endorsed by, or in any way officially connected with Valve Corporation, or any of its subsidiaries or its affiliates. Lambda1VR is an unofficial port of the Xash3D-FWGS engine, which was originally written by Uncle Mike as a fully compatible open-source GoldSrc engine alternative, more details on that extraordinary project can be found here: https://www.moddb.com/engines/xash3d-engine However this port (Lambda1VR) is not affiliated, associated, authorized, endorsed by, or in any way officially connected with the Xash3D team. This port was developed using the now deprecated Xash3D port found here: https://github.com/FWGS/xash3d

Lambda1VR is covered by the GPL 3.0 license which is inherited from the Xash3D-FWGS project. The HLSDK sub-repository and associated works (which include the original 6DoF weapons code by Max Vollmer) are in a separate repository wholly covered with the Valve Corporation Half Life 1 SDK LICENSE (https://github.com/DrBeef/hlsdk-xash3d).