What is Unreal Engine 5’s Lumen?

by Nicolai Baskin

Is Lumen better than Raytracing?

Lumen Global Illumination in UE5 is much better than Raytracing. Unreal Engine 5’s Lumen results in faster framerates, with less resource use, creating a much more beautiful user experience.

Read this article on RTX Raytracing vs Lumen.

You can also get a full on examination of Lumen from the professionals at Epic Games.

What is UE5?

Unreal Engine 5 uses nanite mesh to render triangles scaled dynamically. It also includes the Lumen System for realtime global illumination. It allows UE5 to import film quality assets in game, or film production. It is backwards compatible with Unreal Engine 4, and is the premier and most after game engine on the market.

Is Unreal engine expensive?

No, it is completely free if you earn less than $3000 a quarter, or 5% of gross revenue if you go over that.

Getting started with Lumen:

Lumen is the order of the day. Lumen is the new global illumination system for Unreal Engine 5. It is designed to replace RTX Raytracing over time, and achieves similar results without anywhere near the performance overhead.

So, Lumen is what exactly?

It is a the new lighting system, and it is really nice.

Lumen is realtime global illumination in play or in editor, which means you can move around lights and they will update automatically without having to bake the lighting after every change. It also is set to replace RTX Raytracing, taking away a large advantage for the Nvidia line of cards.

It also handles reflections. You can put these beautiful emissive textures on anything…. Just create a sphere, put the material on, and it will illuminate your entire level, it is now a beautifully functioning light. You can alter it with the sliders. Immediately I want to make a character covered in this emissive material. You could make glowing enemies in an otherwise pitch black level, and when you kill them all the level goes dark.

Just off the top of my head.

New Console Command System:

Lumen works very well with the regular static mesh. Nanite of course works well too.

Unreal 5 has a console command interface built right into the engine, it is always there,

This is a nice feature. It acts as a sort of bridge between a standard editor and writing in code.

You can type in commands and the game will update in real time, you have to study them a bit to get results, but you can get coding level responses out of just typing a few commands into the terminal. You can get more specific and cover a broader range of functions than just working through the editor as normal.

Trying it out:

I am now booting up the Unreal Engine 5 for the first time.

We’ll test it out with procedural city generator and ai daily life.

Then I’ll throw in – Actually I’ll just throw my whole project in there

and see how it performs.


Daz to Unreal Plugin is incompatible with Unreal 5,

All assets created in Daz to Unreal will not function,

Please download this asset pack to continue.

[Imports Procedural City Generator into Blank Project]

[It boots]

Very nice, it’s importing the static meshes, give me a few minutes….

While we wait, check out our website, we can teach you how to develop games:

What is Lumen?

While we’re waiting, let’s discuss lumen. Lumen is enabled by default in new projects and disabled by default in existing projects to ensure it doesn’t crash any existing projects.

You can enable it through the project settings.

You can also enable Generate Mesh Distance Fields, Lumen reflections and general illumination can then be toggled back and forth to compare.

Lumen GI:

Lumen GI has an emphasis on indirect lighting. You can move objects and the shadows will alter dynamically in real time, shadows bounce of the walls almost infinitely and create nuanced and realistic shadows.

In the example video, my jaw hit the floor when I saw, first the detail of the cave, with the Nanite Mesh’s millions of triangles, it looks like noise when enabled in the visualization, that’s not noise, that is detail level. But, when he then, in real time, dragged the rock across the roof of the cave where the light was coming in, and I could see the lights changing as they gradually merged to dark and went out.

Words, simply fail to describe it, you must see it for yourself.


The beautiful new Unreal 5 tech demo:

Check this out at the listed timestamp. There’s no point trying to explain it, you need to see it to understand. And then, you need to have experienced the previous engine, in it’s full glory, dwarfed to nothingness, to understand how beautiful that is programatically and as a designer. It’s like the difference between NES and SNES, or SNES to PS1. It is so good, it is a new generation of gaming.

I’d like to see what Unity has to match this,

Because right now, I am selling my ship to the pirates, tying up my crewmates,

and throwing them off the ship at swordpoint. For a pat on the head and a bag of silver.

I will soon become a pirate.

Unity must now make me an offer I can’t refuse or face total irrelevance.

Testing the Lumen System:

Ah there, it’s done, and it looks beautiful.

It’s still PCG, but it has an undefinable shine to it.

Not sure how to put it, it just looks ‘nicer’.

Let’s enable lumen, eh?

Rendering > Global Illumination. Set Dynamic Global Illumination Method to Lumen.

Yeah, that immediately looks nicer…..

Let’s check out the showcase level.

For our pleasure, I have enabled Support Hardware Raytracing, Generate Mesh Distance Fields, Use Hardware Ray Tracing when available, Reflection Method Lumen, Dynamic Global Illumination Method to Lumen.

Restarting, compiling shaders.

What light sources are supported?:

All standard light sources are supported.

Light functions supported on Directional Light only.

I also like that it does not support static light sources. Basically, Unreal 5 doesn’t like lights that don’t move, they’re called baked lights, ew, Unreal 5 GI does not support or endorse such vileness. Unreal 5 has lights that move, and look beautiful in editor as you move them around. It is not some cheap joke, where lights sit in one place, and then you bake for 4 hours to get a really nice light setup. It just…. It is just better.

This is one of the bad headaches cured by the magic Unreal 5 pill.

Quality of life improvements.

It’s like being told my beautiful high quality FBX’s don’t need to import at massively reduced function, they will upload in full, and beautiful, maximum high quality. It will…. let’s not even get into what Unity does to my FBX’s, or their solution of HDRP, being so bad, it should be illegal. Or how I felt when I learned that polygon count, mesh memory, and draw calls no longer determine framerate.

When you’ve designed in game engines for a while, there is a profound sense of relief, like a large weight being taken off your back, after years of performing some menial unpleasant task eternally, and then finding out the task, is simply absent in the new engine. It is the feeling of massive amounts of work being saved.

Ah we’re done, compiling shaders.

7% complete, 15,963 remaining.

I guess I’ll go walk around.

And then we will import one of my REALLY NICE Fbx’s,

and see how beautiful the rabbit hole goes.

How does it look?

And here we are with the lights fully enabled.

Keep in mind, this is a cartoony, low quality indie pack,

augmented to ridiculousness.

Look at the fine details in the shadows.

And this is how a cheesy cartoon game looks.

Now let’s just quickly import that high quality character model, and see how she looks.

Let’s import my character:

Compiling shaders.

Half my job is compiling shaders.

There we go,

There she is:

As you can see, a very high quality model for an indie game.

I have even nicer ones, but I still need to acquire the digital rights to use them legally.

Evidently, it imports at super high quality.

And here is my retargetted skeletal mesh assigned to my main character.

A few bugs I’ll fix later, but….. Well…..

Soak it in.

Welcome to Unreal 5.

Waiting on the Daz to Unreal Bridge to get it’s update.

So long for now.

Related Articles


Your email address will not be published. Required fields are marked *