Unreal Engine 5, [UE5 Developer Availability 2022-04-05]

That is nice, and is "using HW RT" (and certainly waaaay better than the old UE4 RT reflections destroying performance) but still, I have expected a little more. More performance while looking better at the same time, like Alex said in a DF Direct.
I don't understand where people are coming from on this comparison. These are two very different algorithms... it's not as if it's software tracing the triangle BVH. The "software tracing" is using an entirely different data structure (SDF), which is extremely cheap to trace. That said, the tradeoffs in terms of both performance and quality are very different. I encourage people to go read up in the Lumen documentation as both methods have various pros and cons and lots of tweakable settings.

FWIW there are very similar tradeoffs with virtual shadow maps vs. (triangle) RT shadows.

Fundamentally though there's no reason to expect one to always be faster or higher quality than the other. This is definitely a place where I am starting to get a "we're trying to find ways to make this demo fit our narrative of X GPU is better than Y GPU" vibe to be honest... please don't fall into that silliness. As with anything that uses new techniques, parts of the frame are likely to be faster/slower on different GPUs than we have seen in the past. It's unreasonable to assume that entire frame times can be used to reason about the performance of specific hardware features in the frame - a modern game frame (especially in UE5) is far too complex for that naïve analysis.

Luckily all the source code and profiling tools and such are there for you to go look yourself. I suggest starting with profilegpu as while there are some caveats, it's a pretty reasonable place to get a high level overview of the GPU frame.

In terms of playing with various Lumen settings and some of the associated tradeoffs, there's a few pointed out in this video from a few days ago:
There's obviously far more than just that too, but hopefully that gives people an idea of the depth of the tradeoffs that are available, and why it's certainly more complicated than "benchmark GPU X and Y and draw conclusions based on that". The entire engine and sample are available with full source and ability to play with any of the settings yourselves - please make use of that if you're interested in the technical details! There's no need to speculate on any of this.
 
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We need footage of these reflections on cards without HW RT badly. I've looked up so many videos of Non HW RT cards, and nobody would bother to come close to one of these frickin' windows :)
Just turn off hardware RT in the project? Or change just the lumen reflections setting. There's Lumen visualization modes too in editor that let you look at the Lumen scene, Lumen reflections, etc. directly.
 
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Just turn off hardware RT in the project? Or change just the lumen reflections setting. There's Lumen visualization modes too in editor that let you look at the Lumen scene, Lumen reflections, etc. directly.
For some reason, turning off HW-RT doesn't work. I checked GenerateMeshDistanceField in project settings and restarted the project, but still, as soon as I disable HW-RT in command line, Lumen switches off and a red error message tells me to enable SDF, which I did.

But yeah if I could get that working, then I'd be able to make nice comparisons.
 
In the Lyra project I can switch between SW and HW Lumen after enabling HW-RT.

The differences can range from minor to very noticeable.

Here's a nice comparison I've made. https://imgsli.com/MTAzNzgx

So yeah, that's a big difference, isn't it?

And the performance is the same between these screenshots! I think it's nice UE5 uses HW-RT in a much more efficient way than UE4, the Epic team did a great job there.

I really wonder if there are big differences in the Matrix sample as well, especially in terms of the Global Illumination. Can't wait for Alex' video now!
 
With Matrix Awakens, you can press "~" to open a console. Double-tap that to hold the console open.

Then you can put in a command like:

sg.globalillumination 2

credit to Ray Harrison.

The graphics settings go up to 5! So, super sharp reflections at 5?

Higher settings should stress the ray tracing hardware, I suppose!
 
@Dictator since DF talks to Epic often. Why not ask Nicholas Penwarden (VP of Engineering) a very pointed question: "Why haven't Epic released the lumen in the land of nanite demo. Its a very efficient display of use of Nanite & Lumen. Is there any particular reason why you have chosen not to release it?"
 
@Dictator since DF talks to Epic often. Why not ask Nicholas Penwarden (VP of Engineering) a very pointed question: "Why haven't Epic released the lumen in the land of nanite demo. Its a very efficient display of use of Nanite & Lumen. Is there any particular reason why you have chosen not to release it?"
If I can give my guess... the Matrix demo is more impressive in a marketing and consumer view than the Land demo.
They could of course release both but if they had to choose Matrix is the better option.
It is a demo that looks more like a game while the Land was not.
 
https://tjatomica.itch.io/superman-ue5
Please note that this is an incredibly heavy game and lower end PC's will struggle potentially. Even on a 3090 I have run into streaming issues...
Again, this is based on Epic's Matrix Demo, just for fun, and I haven't done any kind of optimisation myself, it's just plug and play.

Either way this is just for those of us who one day dream of a Superman open world game, I hope this scratches that itch a little bit for now.
 
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