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

But surely an engine can be made that would directly make use of the hardware that's available? Just as the same engine will make use of the extra 2tflops on the Xbox Seeies X, or the RTRT capabilities of the next Nvidia card.

If Epic have been working with Sony on this engine, which they have stated. The we can only assume that it has the capacity to make use of the significant IO capabilities. Surely that makes logical sense?

It's a bit lile people saying that deveopers will not make use of the extra compute in the Xbox because they can't conceptualise it. Doesn't mean it won't happen.

We don't know the extent of this demo's customisation for the PS5 (we know it runs on everything and runs at least okay on PC, in editor, with overheads). We don't know just how much work Sony have done with Epic on this demo - clearly they're providing devkits and updates on development software. Epic will be working closely with Sony, MS, Nvidia, AMD, Intel and everyone they can / need to.

I'm sure you can use the PS5's bandwidth and IO. I'm not sure this demo demonstrates anything that's only possible on that. We have some comments from Tim Sweeny, who isn't working on either Nanite or Luminous, and lack qualifying details. We also have some comments from an actual engineer working on the demo that are potentially somewhat contradictory, or then again potentially not that contradictory depending on what details you chose to insert into the blanks.

We'll know for sure when the demo lands on PC. If the demo runs okay on PC, even without DirectStorage, we'll have a good starting point to look back in time and see through the fog.
 
Again, another tweet from Tim Sweeney saying hardware decompression is crucial to the demo as we saw it:



I think it's possible you're reading too much into that quote. Tim was asked why the demo was shown on PS5 and not PC, and he responded with a post extolling the advantages of the PS5 IO (which are a given). That's not the same as saying it can't be done on a PC though. Maybe it can't, but until someone from Epic explicitly states that (or we've gone a few months and there's no sign of it on PC) then it's premature to reach that conclusion, especially in light of the previous laptop quotes.

Perhaps you should ask Tim on twitter, he seems quite open to providing feedback.

Fast storage and hardware decompression is what makes it possible, as explained by the engine makers, and that makes two possible candidates for making this possible: the PS5 and the SeriesX.

There are no hardware decompression solutions for the PC.

So we know that 5.5GB/s of Kraken compressed data takes 9 Zen2 cores to decompress in real time. We also know that PC's don't use Kraken compression (at least not for everything), and there seems to be some debate as to whether all data on a PC drive would need to be decompressed in software before use or not (textures in GPU native formats being one specific question mark). So to give this argument more context, are you able to advise roughly what percentage of game data that is loaded from disk on the PC needs to be decompressed in software, and what the decompression hardware requirements for that are?

demo of UE5 != rendering this in real time.

My understanding is that the engineer specifically referenced the PS5 demo when mentioning he had it running on the laptop at 40fps. Specifically he said something like "the scene you've just watched" (the opening scene) is running on the laptop etc..."

That still doesn't prove anything of course as the settings could have been different (although you could argue that would make the comparison meaningless in the first place so why mention it at all), and he may not have meant the final scene at all.

Sweeney wrote that UE5 would run great on PS5, SeriesX and high-end PCs, with features that can scale down the content to present-day hardware (hence the laptop running it).
I don't recall him saying anything about a particular discrete GPU, or a fast SSD on a PC:


You insert a comma which implies that Tims comments about scaling down features referred to present day PC's but I don't believe that was his implication at all. He clearly separated the two points (high end PC's, and features that scale down for present day hardware) as separate bullet points. They are not part of the same sentence. But more importantly he specifically qualifies the statement about present day hardware saying that this is for platforms that will use traditional rendering and lighting techniques. i.e. he's talking about current gen consoles including Switch. It's hardly necessary for a high end Turing based GPU to be limited to "traditional rendering and lighting techniques" rather than full fat Nanite and Lumen. Therefore I don't think it follows to conclude he's talking about the laptop there.
 
Highly doubt anyone has already tapped the ps5 ssd to its fullest yet (if that will ever happen, cause you know, the rest of the system must cope with the ssd also).

You might be right, but if true that means the console is unbalanced and they only used their top tier SSD as a marketing argument.

We have some comments from Tim Sweeny, who isn't working on either Nanite or Luminous, and lack qualifying details.

I think it's a bad argument... he's a programmer and the CEO of EPIC, which means that he can obtain all the details he wants from the guys who worked on both Nanite and Luminous.
 
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I think it's possible you're reading too much into that quote. Tim was asked why the demo was shown on PS5 and not PC, and he responded with a post extolling the advantages of the PS5 IO (which are a given).
He was asked why the demo was shown on PS5 and not PC, and he answered why the demo was shown on PS5 and not PC.
Assuming he didn't provide a direct answer to the direct question is what I'd call reading too much, IMO.



So to give this argument more context, are you able to advise roughly what percentage of game data that is loaded from disk on the PC needs to be decompressed in software, and what the decompression hardware requirements for that are?
What games do you know that don't have the bulk of their assets into packed files?


That's not the same as saying it can't be done on a PC though.
Q: Why did you use a boat and not a car to cross the river?
A: Because the boat floats and there are no bridges.
Aha! You didn't say you couldn't have crossed the river with a car!

¯\_(ツ)_/¯



You insert a comma which implies that Tims comments about scaling down features referred to present day PC's but I don't believe that was his implication at all. He clearly separated the two points (high end PC's, and features that scale down for present day hardware) as separate bullet points.
I'm not sure what you mean with the comma thing, but Tim Sweeney didn't say the rendering run they showed last week could have been done on the SeriesX or high-end PCs. He said Lumens and Nanite would also be running on SeriesX and high-end PCs.
 
He was asked why the demo was shown on PS5 and not PC, and he answered why the demo was shown on PS5 and not PC.
Assuming he didn't provide a direct answer to the direct question is what I'd call reading too much, IMO.

Most of Sweeneys comments about why ps5 and not PC gets fixed when DirectStorage is released. Data will move very nicely after that is available. Of course decompression and wide variety of hw is still issue after that but that's life as usual on PC side. PC will catch up and people with highend hw will keep harping about someone keeping things back be it consoles, laptops, old machines or lack of coffee machines.

I just don't see the need to make this into platform war. Overall streaming, nvme ssd's, decompression,... great things and difficult to see why they wouldn't be future in all platforms. Streaming performance will be another quality setting that scales on per machine/game basis. We will keep peeping at 200% crops to figure out what's what. Short term it is, what it is. Consoles at launch seem to "always" provide a nice boost to lowest common denominator and push boundaries. That's great. Eventually consoles fall behind and then there is new console generation and the same arguments start all over again.
 
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Eventually consoles fall behind and then there is new console generation and the same arguments start all over again.

Definitely true and it's likely that some of the same people that are today stating that 5-9GB/s cannot be used are the same people that a year or two from now will be laughing at the PS5 because their PCs have got 15GB/s of bandwidth and appropriate decompression. Likely that the irony will be long lost by then.

It really shouldn't be about platform wars - you can tell exactly the platform that people prefer by their evident confirmation bias. People don't appear to often "like" valid information, they like wherever information suits their bias.

The truth of the matter is that Epic have created an engine that'll scale to the strengths of the platform it's being used on. SSD speed and decompression is one such priority. Unfortunately it has upset those who choose a platform that doesn't *yet* have that functionality.
 
What games do you know that don't have the bulk of their assets into packed files?

Compression of .pak files is optional rather than mandatory according to this link:

https://docs.unrealengine.com/en-US.../Packaging/index.html#compressingyour.pakfile

But regardless, that doesn't really answer my question. You're using systems which use custom compression formats for everything on disk where we know the software performance cost of that to conclude that PC's cannot properly utilise high speed SSD's because they lack decompression hardware. So I'm assuming that in order to reach that conclusion you already roughly understand the software decompression requirements for a typical PC game. So I'm just enquiring as to what they are. With supporting links if you don't mind.

Q: Why did you use a boat and not a car to cross the river?
A: Because the boat floats and there are no bridges.
Aha! You didn't say you couldn't have crossed the river with a car!

¯\_(ツ)_/¯

Or another analogy could be that a promoter of a boat race arrives in one competitors boat as opposed to anothers and is asked why, is it because the boat you arrived in is faster? And he replies that the boat he arrived in is very fast and it uses a really efficient engine. Not the same as saying "yes it's faster", or "the other boat wouldn't have got me here in time". Tenuous analogies aside, I'm not drawing a conclusion one way or the other, however Tim could very easily have said, "this demo wasn't possible on current PC drives because..." but he didn't say that, he simply talked about what he liked about the PS5 drive. Developers, especially very high profile ones like him tend to avoid direct comparisons between systems but will of course talk about the technical merits of a particular system (in isolation from others) quite freely.


I'm not sure what you mean with the comma thing, but Tim Sweeney didn't say the rendering run they showed last week could have been done on the SeriesX or high-end PCs. He said Lumens and Nanite would also be running on SeriesX and high-end PCs.

Yes but you're drawing a link between Tim saying UE5 will scale down to "current generation platforms using traditional rendering and lighting techniques" and that being what's allowed this specific demo to run on the 2080 powered laptop. But I'm pointing out that a 2080 powered laptop would have no need to use "traditional rendering and lighting techniques". So that link is a spurious one.

Also, I did a little more digging around specifically what has been said with regards to this demo and PC hardware and PC Gamer have this:

https://www.pcgamer.com/fast-ssd-st..._source=twitter&utm_campaign=buffer-pcgamertw

PC Gamer said:
I couldn't get any exact specifications from Epic, but on a conference call earlier this week I asked how an RTX 2070 Super would handle the demo, and Epic Games chief technical officer Kim Libreri said that it should be able to get "pretty good" performance. But aside from a fancy GPU, you'll need some fast storage if you want to see the level of detail shown in the demo video.

To be clear, I don't see this as conclusive either, as PC Gamer may have been adding their own conclusion about storage and detail settings to Liberi's quoted statement, or this may be a paraphrasing of Liberi's actual words. However I'd say that for the time being, until we have further evidence one way or the other, this is sufficient to at least cast doubt over any derived conclusions that this demo is only possible with this level of detail and performance on the PS5 (or XSX for that matter).
 
Just looking to screen grabs from the tech demo, details are ok, but what's about razor edged shadows?
this is a limit of the UE5 itself?


Nothing wrong with the razor edge shadows in that image. The closer the two objects are the sharper the shadow 1) object sun is shining on and 2) the object the shadow lands on These two are real close so the shadow will be sharp.

The further the two objects are the blurrier it will get. Don't believe me, go out side in a cloudless day and have a look at all the shadows the sun casts.
 
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Again, another tweet from Tim Sweeney saying hardware decompression is crucial to the demo as we saw it:







Quotation needed. Where did I ever say only PS5's IO makes it possible?

Fast storage and hardware decompression is what makes it possible, as explained by the engine makers, and that makes two possible candidates for making this possible: the PS5 and the SeriesX.

There are no hardware decompression solutions for the PC.
Willfully ignoring Epic CEO's very clear statements about why the demo was run on a PS5 and not a PC makes me wonder who's trying to secure what narrative.



A demo of UE5 != rendering this in real time.
Of course they can showcase UE5 on a PC. They couldn't have developed the whole engine on PS5 and SeriesX devkits, could they? Why is this even in question?


Sweeney wrote that UE5 would run great on PS5, SeriesX and high-end PCs, with features that can scale down the content to present-day hardware (hence the laptop running it).
I don't recall him saying anything about a particular discrete GPU, or a fast SSD on a PC:


You conveniently left out this tweet where he is asked if it can run on PC with same quality/fidelity. Tim says its too early to know and that you should look forward to bench-marking it. If its impossible as you say, He would just say NO it can't be done, definitely not that its too early or that you should go wild bench-marking it in a-lil over 6 months. He will just say no. Can't be done. As you have repeated.

 
Quotation needed. Where did I ever say only PS5's IO makes it possible?

Fast storage and hardware decompression is what makes it possible
That's part of the IO.

We have some partial quotes from Epic Games chief technical officer Kim Libreri:

I couldn't get any exact specifications from Epic, but on a conference call earlier this week I asked how an RTX 2070 Super would handle the demo, and Epic Games chief technical officer Kim Libreri said that it should be able to get "pretty good" performance. But aside from a fancy GPU, you'll need some fast storage if you want to see the level of detail shown in the demo video.

To that end, Unreal Engine 5 is being "optimized for next-generation storage." The PlayStation 5 storage tech is "god-tier," says Sweeney, while PCs have some catching up to do. That said, "on a high-end PC with an SSD," and especially with an NVMe SSD, we should get "awesome performance" from Unreal Engine 5 games. (With a good GPU and CPU too, of course.)​

Anyway, I can't be bothered to discuss this any more. This thread had settled down to some nice technical considerations before you came in late with size-nines stopping over old ground already covered with some heavy-handed assertions about interpretations and an absolute statement that there's no ambiguity and no-one should be discussing things that go against your interpretation. I expect the following few pages to be back-and-forth between people arguing over sound-bites and tweets and whether an engineer did show the demo or not. The real, interesting discussion isn't going to happen until Epic do a conference, and then we can talk about it in the Graphics Rendering forum without platform-preference agendas skewing discussion.
 
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That's part of the IO.

We have some partial quotes from Epic Games chief technical officer Kim Libreri:

I couldn't get any exact specifications from Epic, but on a conference call earlier this week I asked how an RTX 2070 Super would handle the demo, and Epic Games chief technical officer Kim Libreri said that it should be able to get "pretty good" performance. But aside from a fancy GPU, you'll need some fast storage if you want to see the level of detail shown in the demo video.

And you don't bold what Kim said.
 
David, you are ignoring the fact that he said the assets were not fully "cooked". You're also ignoring every statement from Epic.

I think we can all agree that the sooner that demo is released for public consumption the better.

The fact of the matter is, whether you like it or not, the PS5 currently outperforms all other platforms for IO speed right now. That demo that Epic released apparently showcasing it, may or may not, be evidence depending on your comprehension on the situation.
 
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Hypothetically speaking, if there were an IO bottleneck on a system that needed to constantly stream data (megatexture is a good example with differing quality textures); how would that bottleneck manifest when playing a game?
 
Hypothetically speaking, if there were an IO bottleneck on a system that needed to constantly stream data (megatexture is a good example with differing quality textures); how would that bottleneck manifest when playing a game?
Take any open world or racing game on HDD-less X360?
 
Hypothetically speaking, if there were an IO bottleneck on a system that needed to constantly stream data (megatexture is a good example with differing quality textures); how would that bottleneck manifest when playing a game?

because of the tech, they compute full detail model from disk to reach the pixel-level details, I suppose:

if the system lacks compute power, it would start from a lower resolution model, to do easier and lighter conversion to pixel level (and/or process less pixels, so lower screen resolution)
if the system lacks ssd speed, it would start from a lower resolution model, to take less I/O bandwidh (and/or use some sys memory to cache the asset streaming)
 
So I'm assuming that in order to reach that conclusion you already roughly understand the software decompression requirements for a typical PC game. So I'm just enquiring as to what they are. With supporting links if you don't mind.
I already asked you how many examples you'd need to acknowledge that virtually all videogames have their assets compressed, to which you never responded.
I showed you one example of a very high-profile PC game which you quickly disregarded.
I'm not going to bother with providing X amount of examples just so the goalposts can move indefinitely. Just google for [any game] + compression error and see what you'll find.




You conveniently left out this tweet where he is asked if it can run on PC with same quality/fidelity.
I didn't conveniently left out anything. He wasn't asked if the same demo could run on PC. He was asked what kind of PC would be needed to run the same demo.To which he answered it's too early to know. Perhaps you can't run it at all, or perhaps you need a 24-core Threadripper so you can dedicate 8+ cores just for software decompression. Or perhaps with a significantly slower I/O you'll need a PC with 64GB of RAM to keep most of the level within the RAM, after a loading screen to decompress the data.


This thread had settled down to some nice technical considerations before you came in late with size-nines stopping over old ground already covered with some heavy-handed assertions about interpretations and an absolute statement that there's no ambiguity and no-one should be discussing things that go against your interpretation.
And what is my interpretation?
Last page you were accusing me of securing a narrative that only PS5's IO makes this possible (i.e. throwing a fanboy accusation, how nice), to which I asked for proof of such and you didn't provide.

And now I'm guilty of what, stating that a hardware block for data decompression - that is also present on the SeriesX - is one of the several factors that are instrumental into making last week's demo run possible? And that there's no such thing for the PC, on any publicly known roadmap?
I plead guilty for that.



Take any open world or racing game on HDD-less X360?
Did all X360 games need to be run-able on a HDD-less X360?
Honest question, because I thought after a couple of years a lot of games were demanding the HDD to even run, and by ~2010 at least all AAAs were in that position.
 
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