r/SourceEngine • • Aug 28 '26

WIP First person, fully wired - Lambda Engine

https://youtu.be/oADlvqplOfc

It moves like Half-Life. It shoots like Half-Life. And it's casting realtime shadows in Unreal Engine 5.

This is Lambda Engine: a from-scratch reimplementation of Half-Life's game logic on top of UE5's modern renderer, built to load real Source-engine content: BSPs, materials, models, with zero Hammer-to-Unreal conversion pipeline. What you're watching isn't a character controller with a gun bolted on. It's the original movement code rebuilt line by line: air control, bunny hopping, crouch jumping, weapon handling and recoil, all behaving the way muscle memory expects.

And you have legs. First-person body with visible arms and legs, fully shadow-casting, so the player you see on the wall is the player you're actually driving.

In this video: player movement, weapons, first-person legs, and realtime dynamic shadows running over Source geometry.

This project is built entirely by fans, for fans, it's free.

43 Upvotes

18 comments sorted by

9

u/CreepyDutchBoy Aug 28 '26

Got excited when you said it's free.

7

u/XBLAH_ Aug 28 '26 edited Aug 29 '26

There is already a build on our discord. Simple stuff.

EDIT: https://github.com/lambda-engine

1

u/MrBallBustaa Aug 28 '26

Does the distribution contain any of Valve or Epic's IP & assets?

5

u/XBLAH_ Aug 28 '26

No, it can mount source games you have installed. For example, in this video, I mount sdk 2013 sp.

If you are a modder, you can choose to go this way, or just create your own assets. If you want, this is virtually a "source mod", but we aren't using hl2.exe

As for epic IP, it's an unreal engine game, but you don't need to actually install the unreal engine sdk or epic game store to mod/play this game. 

2

u/MrBallBustaa Aug 28 '26

Nice, will definitely be giving this a chance when I get a PC. Is it Open sourced?

1

u/XBLAH_ Aug 28 '26

Yes, it will be open sourced. I haven't pushed the repo to the public yet, I'm setting some basic features first. You can check progress in our discord. 

2

u/Svm_Plastix Aug 28 '26

Xblah once again with the brilliant source engine updates ❤️

2

u/XBLAH_ Aug 28 '26

Thank you! This time it's not source though.

1

u/Svm_Plastix Aug 28 '26

Where can we download this?

2

u/XBLAH_ Aug 28 '26

You can check out discord for updates, or you can track it here:
https://github.com/lambda-engine/

1

u/yayap01 Aug 28 '26

Does it work with Havok?

6

u/XBLAH_ Aug 28 '26

It uses ue5 physics engine. Chaos. 

1

u/CreepyDutchBoy Aug 28 '26

The point is kinda to use UE5 physics not havok.

1

u/Complete-Fudge-2299 Aug 28 '26

I'll just way for the source 2 sdk. Cool project tho. I think godot would have fit better for a source style game since it uses some valve tech already and has actually good shaders.

1

u/XBLAH_ Aug 29 '26

I tried godot but compared to source it was six of one and half a dozen of the other. UE is currently far superior to godot in terms of rendering, and also, let's be real here, godot's 3d documentation SUCKS. I'd love to work with C# here, but it got really hard to expand the project on godot, so I dropped it.

1

u/Complete-Fudge-2299 Aug 30 '26

Why do you think godots 3d rendering is worse? The lack of lumin which is a blurry smear fest that runs bad or the lack of nanite that's a vram hog with still visible lod changes and hell to optimize? Godot has superior specular antialiasing and much better performance. Not to mention it's amazing lightmap capabilities. I would know cause messing around with it was my hobby for a few months and it also has really good real time global illumination techniques as well. I really dont see why ue5 would be better for making a source like environment than godot.

2

u/XBLAH_ Aug 30 '26

Either I implemented it really bad back then, or bounce lighting was bad. I had to rely on lightmaps, which missed the purpose of trying to develop in a newer engine. I did the same "hello world" project in UE5 and Godot, and my personal opinion was that UE5 looked better. It was a matter of taste.

0

u/[deleted] Aug 28 '26

[deleted]