Biggest weakness in RT games today..

[Deleted member 13]

Hey guys,

I thought about putting this in the Metro thread but this actually extends to all other RT games so I decided to make it's own thread.

There is a very annoying side effect of full on RT games using Global Illumination (although it is also seen in the UE5 demo with Lumen).

Latency.

If you pay attention enough to the objects/camera moving dynamically in a RT game, you will see a blur mimicking motion blur on the object or a delay in the lighting once the camera is still. It is absolutely annoying. I found this in Metro: EE and the Marbles demo. It's also seen in other games that mimic GI like Lumen in the UE5 demo when the ceiling in that cave broke apart and the GI bounces poured in the cavern.

This will more than likely be a thing until graphics cards/consoles get a LOT more powerful to remedy the delay. Right now I believe the RTX3090 is about the fastest in resolving the ray bounces.

FYI folks. RT doesn't come without some caveats.

 

[yewles1]

The tech for RT acceleration is still in its infancy, think 3D geometry on 16-bit consoles...

 

[Dr Bass]

Are you saying actual latency is calculating the bounces the rays take so it affects the image quality? Like you can see the RT effects "catch up"?

The only RT stuff I've done is in an offline "toy renderer" for experimenting, and basically learning that graphics programming is tough enough that I probably don't need it in my life at this point. I have zero knowledge of the realtime implementation of how it works. I mean I've read about BVHs and those things but ... that's a really interesting point about the latency. How can they improve that?

 

[Bo_Hazem]

What's in mind though is how long can the nodes keep shrinking? Should we jump ship from silicon to another new method? I also think PC should go ARM and see the brilliance of M1/M2 chips from apple. Yup, they're massive vs single CPU's/GPU's, but overall they're combining RAM/VRAM/CPU/GPU and then some!

 

[yewles1]

What's in mind though is how long can the nodes keep shrinking? Should we jump ship from silicon to another new method? I also think PC should go ARM and see the brilliance of M1/M2 chips from apple. Yup, they're massive vs single CPU's/GPU's, but overall they're combining RAM/VRAM/CPU/GPU and then some!

If we can find another conductor more capable than silicon, then that may be the way to go, otherwise we'll have to see whether or not energy really does have difficulty passing through transistors once we reach the pm range.

 

[Darth Vader]

Well to be fair, I think RT is overrated, especially in games today. It's more of a marketing ploy than something useful.

Case in point - TLOU Part II. No RT, running on the PS4, absolutely stunning use of baked lighting.
Dying Light 2 - RT looks awful and the game does not look better than a PS4 game with baked lighting, even on next gen hardware.

Suffice to say, intelligent use of RT, even for audio, is cool and betters the overall experience.

 

[ethomaz]

To be fair I think Metro implementation bad.
Places that should have a dark tone in the game become too bright like you not in a closed room with low illumination.

But that can be due the game being designed to non-RT lighting so when dev forced it the result is not actually good.

The old lighting in Metro is better imo… it can be worst technically but the visual and tone is perfect while the RT lighting breaks that.

Maybe that is one of the issue with the new RT… devs needs to change/adapt how they do things.

 

[ethomaz]

Well to be fair, I think RT is overrated, especially in games today. It's more of a marketing ploy than something useful.

Case in point - TLOU Part II. No RT, running on the PS4, absolutely stunning use of baked lighting.
Dying Light 2 - RT looks awful and the game does not look better than a PS4 game with baked lighting, even on next gen hardware.

Suffice to say, intelligent use of RT, even for audio, is cool and betters the overall experience.

I don’t think it is overrated.
What you see in games today are not the real path tracing… it just some minor features made in RT.

The lack of hardware to run games in full path tracing is a issue.

So while we don’t reach a hardware level to run in real-time full games in ray-tracing then we will have that half-ads RT we have today.

We are in a intermediate process yet… it will take perhaps 10 years or more to hardware reaches a point where full path tracing is possible without any rasterization being used.

 

[Darth Vader]

I don’t think it is overrated.

I think it's overrated the same way I think having a virtuoso in your band is overrated. What matters is the vision, stylistic choice, etc. Why does it matter you can path trace your lighting when your art style is garbage?

 

[ethomaz]

I think it's overrated the same way I think having a virtuoso in your band is overrated. What matters is the vision, stylistic choice, etc. Why does it matter you can path trace your lighting when your art style is garbage?

Well path tracing will end giving way better results visually than what we have today.

It just hardware is not there… so mixing some little takes in RT with the actual rasterization ends not that good imo.

 

[Darth Vader]

Well path tracing will end giving way better results visually than what we have today.

It just hardware is not there… so mixing some little takes in RT with the actual rasterization ends not that good imo.

I'm not sure you're getting me

Tech doesn't matter if you don't have a good visual style. You can have a Ferrari engine in a tractor, it won't be a supercar.

 

[yewles1]

I'm not sure you're getting me

Tech doesn't matter if you don't have a good visual style. You can have a Ferrari engine in a tractor, it won't be a supercar.

No, but you can have a tractor shift in a Ferrari and piss off a customer to the point of he making his own competing car company...

 

[Sharinghack]

Hey guys,

I thought about putting this in the Metro thread but this actually extends to all other RT games so I decided to make it's own thread.

There is a very annoying side effect of full on RT games using Global Illumination (although it is also seen in the UE5 demo with Lumen).

Latency.

If you pay attention enough to the objects/camera moving dynamically in a RT game, you will see a blur mimicking motion blur on the object or a delay in the lighting once the camera is still. It is absolutely annoying. I found this in Metro: EE and the Marbles demo. It's also seen in other games that mimic GI like Lumen in the UE5 demo when the ceiling in that cave broke apart and the GI bounces poured in the cavern.

This will more than likely be a thing until graphics cards/consoles get a LOT more powerful to remedy the delay. Right now I believe the RTX3090 is about the fastest in resolving the ray bounces.

FYI folks. RT doesn't come without some caveats.

That effect is called Temporal Ray Tracing Accumulation, derived from the techniques to denoise the ray casting pass. Will not go away until we have hardware powerfull enough to cast billions of rays instantly with no need for denoising pass.

 

[Deleted member 13]

Are you saying actual latency is calculating the bounces the rays take so it affects the image quality? Like you can see the RT effects "catch up"?

The only RT stuff I've done is in an offline "toy renderer" for experimenting, and basically learning that graphics programming is tough enough that I probably don't need it in my life at this point. I have zero knowledge of the realtime implementation of how it works. I mean I've read about BVHs and those things but ... that's a really interesting point about the latency. How can they improve that?

Exactly.

 

[Deleted member 13]

Well to be fair, I think RT is overrated, especially in games today. It's more of a marketing ploy than something useful.

Case in point - TLOU Part II. No RT, running on the PS4, absolutely stunning use of baked lighting.
Dying Light 2 - RT looks awful and the game does not look better than a PS4 game with baked lighting, even on next gen hardware.

Suffice to say, intelligent use of RT, even for audio, is cool and betters the overall experience.

TLOU 2 is going to look leagues better because their team knows how to display the best visuals with very little real estate on the hardware side. Baked lighting is always going to look better than dynamic lighting because it's using offline render to put the lighting result into a framebuffer.

DL2 absolutely looks awful. LOL! Techwise better of course, but their art direction, layout, level design, etc.. all are lacking.

 

[Darth Vader]

TLOU 2 is going to look leagues better because their team knows how to display the best visuals with very little real estate on the hardware side. Baked lighting is always going to look better than dynamic lighting because it's using offline render to put the lighting result into a framebuffer.

And the artstyle and direction is pretty spotless and borderline perfect.

DL2 absolutely looks awful. LOL! Techwise better of course, but their art direction, layout, level design, etc.. all are lacking.

Yep, it looks horrible. Their first "showcase" looked really good, then we got this color vomit of a game.

 

[rofif]

The accumulation is visible.
I am not annoyed by it but it is there.
Actually, it is really similar even in software global illumination games like Uncharted 4 (flashlight levels). You see a light slowly accumulate through grain

 

[Sharinghack]

Related:

NVIDIA’s Ray Tracer: Wow, They Nailed It Again!​

 

[Deleted member 13]

Yeap, very impressive. I would be tempted to take his course just to get a refresher but that'll have to wait till after I retire.

 

[rofif]

RT is pretty amazing but depends what you are using it for.
UC4 does pretty good Gi without RT.... RT came so late, we really catched up with raster