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

I expect the conclusions here are correct, but worth noting gamegpu is somewhat questionable website.

In the past one thing I noticed on gamegpu is for a large table of purported AMD GPU benchmarks, they all scaled 100% perfectly (meaning, EXACTLY) with theoretical. But I believe there have been outside questions about them as well.

Again in this case though I expect the discussion is correct.

 

Thank you for this interesting analysis.

Just from comparing videos, I have been coming to similar conclusions.

Although im somewhat confused. There are definately off screen reflections indicating the usage of HW RT. And in the UE5 Matrix developer video on their YouTube channel, they also say it's using HW RT on consoles, demonstrated by showing the own character reflection in a window.



Now the question is, are these reflections available on non-RT hardware in the PC sample? I wish someone with a non-HW RT GPU could test this.

If not, that means it is using HW-RT in the sample. And if the GameGPU benchmarks are correct, then that atleast means there's no performance impact from having HW-RT.
If yes then that takes the confusion to a whole other level.

Anyway, I am sure these questions will all be answered soon when DF posts their video about UE5.

 

Nice duplication system.
But at least the first few waves are hanging in the air. That was the first thing that struck my eyes.
Also to be a bit nitpicky the car would have squashed these things but they seem to be backed from stone.

 

Those chocolaty buns are the stuff of nightmares!

 

This is Alex's response.



Still, it doesn't explain how the 5700XT is delivering same or faster fps than RTX cards.

 

Yup. These off-screen reflections just scream HW-RT.

Still framerate/visual comparisons between various cards leave a lot question marks unanswered. Not only RDNA1 vs Turing but also Ampere vs RDNA2. If GameGPU is correct, then the CPU limit is neglectable, as these cards scale in GPU performance as they should.

My best guess is the performance between HW-RT and SW-Lumen is just pretty similar. In the editor it is atleast.

That means you get free off-screen reflections and probably some other enhancements on HW-RT capable cards.

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. It is looking better, but not by much and it is performing similar to SW-Lumen. I am aware delivering better performance is not an easy task, as HW-RT requires for the BVH structure to be built while that is not needed on their godlike Software-Lumen solution using SDF.

I guess the reason we are a little disappointed is because SW-Lumen is just way better than it has any right to be. It's just as fast as HW-RT while delivering similar results (if you are not looking for clues like off-screen reflections) That is a great thing for older cards, but it also means newer cards with RT acceleration are not benefitting as much as they could.

 

Offscreen reflections indicate RT, not HW RT. You don't need RT HW or DXR for RT.

 

Lumen is about GI, not réflections, in the first demo shown on ps5 there were SSR in the water, they added HW RT in the Matrix demo, and it uses a mix of RT + SSR + cubemaps.
I don't think there are RT reflections with older cards on PC.

 

Technically yes, but the claims here are that software-based Lumen specifically does not offer offscreen reflections.

Though this could have been changed in the new release? Or perhaps they're doing some other method for this.

 

You seem to be going somewhere with this, makes sense i think, and explains why theres not too much gain in performance when enabling hw RT. There just isnt enough ray traced effects to see these gains. Thats bound to happen in the future though.

Anyway, i truly hope theres someone out there remaking just this little part of Unreal 1 in UE5 on pc.

 

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

On a side note, Lumen also does reflections. It is that clever mix of SSR, RT and cube maps.

 

There are lumen reflections in the release version of UE5:

 

Too bad i dont have a non-HW RT gpu thats in a machine. My main gaming system has a 2080Ti (4 years old this year), the family members pc's either have 3070m-class gpus (laptops) or everything between 2060 and 2070S. Maybe look at the console versions? Though that probably wont give you any like-for-like results anyway.
We will have to wait for Alex he will look at different GPU's and other hardware combinations. He does this for a living and has the expertise and probably the hardware, cant wait for his video on this.
DF also has connections to Epic, as was pointed out in their last DF Direct so thats a good thing aswell.

 

Some more benchmarks:

https://www.pcgameshardware.de/Unre...Matrix-City-Demo-Sample-Benchmarks-1392726/3/

 

Lumen Global Illumination and Reflections in Unreal Engine | Unreal Engine Documentation

so you can have lumen reflections in software on non RT hardware, but must be taxing.

 

A Vega 56 is faster than RTX 2060, there is no way this demo is using any sort of hardware ray tracing.