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[VFX_Veteran]

I thought I'd start my own thread to talk about graphics technology discussion in games.

This thread is about technology advancement in graphics engines that produce stunning visuals.. This thread is NOT about subjective opinions (i.e. "this looks more beautiful to me...")

A few examples:

Unreal Engine 4 used a very complex algorithm of global illumination in their latest engine which had really good results but was too complex and impractical for real time gaming so they scratched it.

FarCry3 uses partially baked-GI solution (light probes) for it's lighting instead of pre-baked light mapping.

TLOU has a neat stencil shadow projection method for extracting fake shadows from objects when turning on it's flashlight.

 

[adelante]

TLOU also employs a neat technique, albeit a little rough, to determine imperfect shadows for characters, cast by indirect lighting which, gives a more convincing effect than typical ambient occlusion methods. I'm still interested to learn how they've achieved that.

 

[VFX_Veteran]

TLOU also employs a neat technique, albeit a little rough, to determine imperfect shadows for characters, cast by indirect lighting which, gives a more convincing effect than typical ambient occlusion methods. I'm still interested to learn how they've achieved that.

When you say imperfect shadows? Are you talking when a character walks up to a wall real close? How do we know that's not the typical SSAO technique?

 

[Dictator93]

This thread reminds me of my failures as a GAFer. Cough Cough.

I'll definitely post in here at some point! Good idea for a thread.

 

[benny_a]

The Tomorrow Childen uses Cascaded Voxel Cone Tracing with major use of async compute.

 

[Kinthalis]

I think the first true global illumination game will be whatever uses nvidias solution. Will probably have to wait a while though. I believe it voxel based, right?

 

[Qassim]

NVIDIA's recently announced VXGI is getting implemented into Unreal Engine 4:

http://www.geforce.co.uk/hardware/technology/vxgi/technology

Edit: It might not be actually - they've implemented in it, but I don't know if it'll make it into an official UE4 release and maintained by Epic.

 

[MrCunningham]

The Tomorrow Childen uses Cascaded Voxel Cone Tracing with major use of async compute.

Not so long ago Nvidia was showing off their Voxel Global Illumination Technology using the latest Maxwell cards, which is essentially what this is, but through direct hardware rendering. There's also a plugin for the Unity engine that supports Voxel Cone Tracing as well. I can definitely see this being implemented in more games in the future.

EDIT: oh damn, already beaten.

 

[lazygecko]

The earlier iterations of the Unreal Engine had an interesting dithering feature when running in software mode, which was a sort of crude method to hide the blocky pixellation of stretched out textures without resorting to filtering which GPUs provided.

Before/after example:

Apparently it was a fairly simple algorithm and not very taxing on the CPU. Makes me wonder if perhaps some PS1 games could have utilized it.

 

[adelante]

When you say imperfect shadows? Are you talking when a character walks up to a wall real close? How do we know that's not the typical SSAO technique?

Because unlike typical AO techniques, characters don't emit drop shadows or black "halo" effects when they're near a surface.

Compare that, to these and I'm sure you'll notice the difference:

Notice how parts of the indirect shadow get darker or more defined depending on the part of the body that's closer to the surface? Also notice how the shadows don't fall directly underneath the character model.

 

[xxracerxx]

From your ravings in the Drake thread, I would still love to see your proof that developers have tapped out the power in the current gen consoles.

Quote in question:

Yea.. I agree with this. I'm just saying giving a company enough time doesn't make them capable of squeezing blood out of a turnip. A lot of developers have mentioned recently that they have squeezed all they can out of the next-gen consoles. Most of those games come at 30fps target.

Would you be at least willing to concur that perhaps we are already 70% of the way to maxing the next-gen consoles?

 

[VFX_Veteran]

The Tomorrow Childen uses Cascaded Voxel Cone Tracing with major use of async compute.

That's freaking awesome! I'd love to see that in a game like Alien or Shadow of Mordor or even AC:Unity!

-M

 

[Cuyejo]

I thought I'd start my own thread to talk about graphics technology discussion in games.

This thread is about technology advancement in graphics engines that produce stunning visuals.. This thread is NOT about subjective opinions (i.e. "this looks more beautiful to me...")

A few examples:

Unreal Engine 4 used a very complex algorithm of global illumination in their latest engine which had really good results but was too complex and impractical for real time gaming so they scratched it.

FarCry3 uses partially baked-GI solution (light probes) for it's lighting instead of pre-baked light mapping.

TLOU has a neat stencil shadow projection method for extracting fake shadows from objects when turning on it's flashlight.

KZ SF does the same too.

 

[VFX_Veteran]

The earlier iterations of the Unreal Engine had an interesting dithering feature when running in software mode, which was a sort of crude method to hide the blocky pixellation of stretched out textures without resorting to filtering which GPUs provided.

Before/after example:



Apparently it was a fairly simple algorithm and not very taxing on the CPU. Makes me wonder if perhaps some PS1 games could have utilized it.

Are you talking about detailed texturing? That was one of the best things I loved about UE since it's inception. It essentially extracted out the high frequency detail of a texture and comp'd it on top of the existing texture as the MIP mapping accessed the lower res maps when the viewer was up close. Very useful technique using a simple linear blend between the two maps based on distance.

 

[Kezen]

Alien Isolation is a more impressive game than I gave it credit for.
http://community.amd.com/community/amd-blogs/amd-gaming/blog/2014/10/07/high-tech-fear--alien-isolation

Real-time radiosity :

Lighting an in-game world with direct sources like lamps and sunlight is not enough to achieve believable or realistic lighting. Here in the real world, rays of light bounce off of all kinds of reflective surfaces and scatter light into the surrounding area; those light rays continue to bounce around the room until all the energy from the rays has been absorbed. That bouncing and reflectivity is called “radiosity.”

Radiosity is an insanely difficult problem to solve in real-time graphics, and most games only fake it by using some form of full-scene ambient lighting. “Approximation” was not good enough for The Creative Assembly, who developed a full real-time radiosity engine for Alien: Isolation.

At the highest level, Alien: Isolation’s engine is constantly updating the radiosity model for the entire scene. This is achieved by placing a set of invisible “light probes” throughout the scene. Using Microsoft’s DirectCompute, these probes process how much light they are receiving from the lighting coming out of the deferred renderer. Lighting contributions from emissive surfaces, like computer screens and LED signs, are added to the data processed by the probe and combined with indirect (reflected) lighting coming from the previously-rendered frame. To light fixed or static objects in the scene visible to the player, the light probe data is crunched into lightmaps, applied to the geometry and rendered out.
- See more at: http://community.amd.com/community/...ch-fear--alien-isolation#sthash.FLl5Cudt.dpuf

 

[Randdalf]

Far Cry 3's solution for GI worked very well because a lot of the game takes places outdoors, they had to come up with a sort of hacky solution to stop light bleeding in interior areas. Either way, the presentation on how their light probes work is fascinating.

 

[VFX_Veteran]

Because unlike typical AO techniques, characters don't emit drop shadows or black "halo" effects when they're near a surface.

Compare that, to these and I'm sure you'll notice the difference:

Notice how parts of the indirect shadow get darker or more defined depending on the part of the body that's closer to the surface? Also notice how the shadows don't fall directly underneath the character model.

Yea, that's pretty neat! It goes away when the direct light hits the object (as seen in the 2nd image). I'm not sure where their artificial lights are coming from (as scene with Ellie walking in the hallway) but it looks pretty damn good.

 

[lazygecko]

Are you talking about detailed texturing? That was one of the best things I loved about UE since it's inception. It essentially extracted out the high frequency detail of a texture and comp'd it on top of the existing texture as the MIP mapping accessed the lower res maps when the viewer was up close. Very useful technique using a simple linear blend between the two maps based on distance.

No, detail textures were a different thing (and they don't work in software mode AFAIK). But it was indeed a very cool feature, and I think it's pretty strange that it didn't catch on in the industry. 2-3 generations later and we're still dealing with a blurry mess when looking at most things up close.

 

[KKRT00]

TLOU also employs a neat technique, albeit a little rough, to determine imperfect shadows for characters, cast by indirect lighting which, gives a more convincing effect than typical ambient occlusion methods. I'm still interested to learn how they've achieved that.

http://miciwan.com/SIGGRAPH2013/Lighting Technology of The Last Of Us.pdf

----

Parallax Displacement Mapping tech from Crytek:

 

[VFX_Veteran]

No, detail textures were a different thing (and they don't work in software mode AFAIK). But it was indeed a very cool feature, and I think it's pretty strange that it didn't catch on in the industry. 2-3 generations later and we're still dealing with a blurry mess when looking at most things up close.

LOL! Agreed.

 

[Dictator93]

No, detail textures were a different thing (and they don't work in software mode AFAIK). But it was indeed a very cool feature, and I think it's pretty strange that it didn't catch on in the industry. 2-3 generations later and we're still dealing with a blurry mess when looking at most things up close.

So it is basically a technique to fake texture filtering (and detail I guess) in case hardware rendering wasn't enabled?

Kinda reminds a bit then of the horrible ability to sharpen textures in Rage, where a sharpening filter is applied to the megatexture based upon distance from the camera.

 

[M3d10n]

There's some interesting techniques brewing up in UE4:

1) Distance field ambient occlusion. Only works for non-animated geometry. A volume texture containing a signed distance field is generated offline for the meshes and it's used to calculate the world-space ambient occlusion. Works for large occluders and off-screen occluders. Is quite a bit taxing right now, but they are working on optimizing it.

2) Ray-traced distance field soft shadows, uses the same distance field volumes generated for AO to ray trace shadows with full penumbra support.

 

[Kevyt]

I loved infamous second son proper energy conservation model which allows light to interact with materials in a natural way:

The particle system is also impressive:

Sucker Punch uses a combination of MLAA and temporal anti-aliasing, a modfied version of SMAA T2x that is impressive (most of the time):

Sucker Punch's engine is superb. I can't wait to see their next game.

 

[VFX_Veteran]

http://miciwan.com/SIGGRAPH2013/Lighting Technology of The Last Of Us.pdf

----

Parallax Displacement Mapping tech from Crytek:

Haha! So they used spheres to represent the characters. That's why the soft shadows look spherical instead of representing the actual geometry of the character. The softness is coming from pre-baking the estimate into light maps using MC.

 

[Warm Machine]

All of the physically based shading going on is pretty cool. Unity 5 has it built in along with a faux real time GI solution that looks incredible. Those two things in combination are making games look spectacular.

 

[VFX_Veteran]

Alien Isolation is a more impressive game than I gave it credit for.
http://community.amd.com/community/amd-blogs/amd-gaming/blog/2014/10/07/high-tech-fear--alien-isolation

Real-time radiosity :

THANK YOU THANK YOU THANK YOU!

Alien Isolation is the most visually stunning game I've seen this year and I always wanted them to talk about their engine.

 

[PLASTICA-MAN]

I thought I'd start my own thread to talk about graphics technology discussion in games.

This thread is about technology advancement in graphics engines that produce stunning visuals.. This thread is NOT about subjective opinions (i.e. "this looks more beautiful to me...")

A few examples:

Unreal Engine 4 used a very complex algorithm of global illumination in their latest engine which had really good results but was too complex and impractical for real time gaming so they scratched it.

FarCry3 uses partially baked-GI solution (light probes) for it's lighting instead of pre-baked light mapping.

TLOU has a neat stencil shadow projection method for extracting fake shadows from objects when turning on it's flashlight.

I can't believe you made a thread about this to continue the flamebait you started in Uncharted 4 thread! You are really stubborn!

Epic scrapped SVOGI, bu they replaced it with the limited LPV solution like the one cryengine but it was only enabled through engine hacks at that time, then they updated their engine with the GI solution from Lionhead. A skilled UE4 user is now trying to enable z higher version of GI by trying to simulate the ditched SVOGI without the cones using: Realtime Dynamic GI + Reflections + AO + Emissive plugin + Approximate Hybrid Raytracing : https://forums.unrealengine.com/sho...Dynamic-GI-Reflections-AO-Emissive-plugin-AHR

TLOU uses geomerics enlighten system with real-time radiosity enabled.

Please don't pretend you know shit about video game tech. It will be a great waste of time to try to discuss anything with you cus teh word doens't doens't even exist in your vocabulary! Cheers !

 

[Kevyt]

THANK YOU THANK YOU THANK YOU!

Alien Isolation is the most visually stunning game I've seen this year and I always wanted them to talk about their engine.

It's a shame there's a lot of stuttering here and there, as well as FMV cutscenes that also stutter.

 

[adelante]

http://miciwan.com/SIGGRAPH2013/Lighting Technology of The Last Of Us.pdf

Wow thanks! Plenty of info in that doc on how they've managed to achieve that effect, most of it way over my head. Then again, my line of work deals mainly with photo compositing/editing, which requires me to create effects that reflect real-life physics/properties so I tend to notice visual details in games that does the same.

 

[Spazznid]

Warframe is about to begin re-doing all of their materials with PBR.

 

[PLASTICA-MAN]

Warframe is about to begin re-doing all of their materials with PBR.

Huh, I didin't know know UE3 could handle PBR, unless they are shifting to UE4.

 

[KKRT00]

Realtime Dynamic GI + Reflections + AO + Emissive plugin + Approximate Hybrid Raytracing : https://forums.unrealengine.com/sho...Dynamic-GI-Reflections-AO-Emissive-plugin-AHR

Wow, thats amazing actually.

 

[PLASTICA-MAN]

Wow, thats amazing actually.

UE4.5 has in fact very good additions too: https://www.unrealengine.com/blog/unreal-engine-45-preview-notes

- Another approach of Screen-space Subsurface Scattering like the one provied Jorge Jiminez a year ago with COD tech demos.

- Ray Traced Distance Field Soft Shadows resulting in mathematically accurate glitch-free shadows. Look how crisp shadows are now, very good fro horror and stealth games:

 

[Kinthalis]

It's a shame there's a lot of stuttering here and there, as well as FMV cutscenes that also stutter.

On consoles maybe. Super smooth on PC.

 

[Fafalada]

How do we know that's not the typical SSAO technique?

The paper on it is publicly available: http://miciwan.com/SIGGRAPH2013/Lighting Technology of The Last Of Us.pdf

Huh, I didin't know know UE3 could handle PBR, unless they are shifting to UE4.

PBR is just changes to shader math. The rest is down to asset authoring, nothing intrinsically tied to particular engine or another.

 

[exmachina64]

I can't belive you made a thread about this to continue your flamebait you started in Unchrated 4 thread!

I can.

 

[Lord_Balkan]

Huh, I didin't know know UE3 could handle PBR, unless they are shifting to UE4.

Warframe doesn't use any form of Unreal. Digital Extremes runs their own proprietary technology.

 

[Kezen]

Huh, I didin't know know UE3 could handle PBR, unless they are shifting to UE4.

PBR has nothing do to with the engine actually. Batman Arkham Knight has a lot of physically correct materials in spite of being based on UE3.
UE4 has a native PRB pipeline though, it saves time.

 

[PLASTICA-MAN]

PBR has nothing do to with the engine actually. Batman Arkham Knight has a lot of physically correct materials in spite of being based on UE3.
UE4 has a native PRB pipeline though, it saves time.

Yes, that is what I mean, UE4 has it integrated. UE3 doesn't, so devs have to do extra work to add it.

 

[AmyS]

The thing that bothers me about Unreal Engine 4 (just a little bit and it is *not* EPIC's fault, it is the hardware manufacturer's fault) is that UE4 been in development for more or less, a decade.. Mark Rein was talking about UE4 in 2005, before Xbox 360 was released. The earliest work had started 2 years before that.

There's no doubt UE4 has been scaled back more than once. Epic had to have been surprised how modest of a leap both Xbox One and PS4 were over the previous gen.

Aug 17th 2005

Rein: "We've been working on Unreal Engine 4 for two years"

Not content with ruling the next gen with its all conquering Unreal Engine 3 - which has been licensed by Microsoft for the 360, Sony for the PS3 and just about every serious next gen PC developer worth their salt - Epic Games has already begun the march to global hegemony in the next next generation, with work on the previously unheard of Unreal Engine 4, now revealed to have begun over two years ago.

"Unreal Engine 4 will be totally groundbreaking and the way games will be done in the future," Rein continued. I don't expect it to be staffed up as a full team for several years. But when people come to work at Epic, they can come here with the knowledge that we're always keeping one eye on the future and they're going to be helping to shape the future of the videogame business" continued Rein.

But Unreal Engine 4? Our minds veritably boggle at the prospect. God alone knows what Epic are cooking up there, but if it's the generational leap forward that Unreal Engine 3 is, then world look out. Rein hinted that it's designed for the next next generation of hardware. Epic feels they got a two to three year headstart on this generation when they started Unreal Engine 3 and aimed it for hardware that was only in the planning stages at the time. Their gamble paid off when Microsoft and Sony chose that level of hardware to power their upcoming next-gen consoles. Rein says the focus for Unreal Engine 4 is getting a leg up on the competition for the next major paradigm shift in computing hardware that is likely to see the light in future PCs and console systems that are mere concepts today.

http://www.computerandvideogames.com/123639/rein-weve-been-working-on-unreal-engine-4-for-two-years/

Tim Sweeney, Part 3: Unreal Engine 4.0 aims at next-gen console war
Posted March 12, 2008

TG Daily: Let’s talk about your game visions for the future and the next Unreal Engine? Where is EPIC going with the Unreal Engine 3.5 and 4.0?

Sweeney: The Unreal engine is really tied to a console cycle. We will continue to improve Unreal Engine 3 and add significant new features through the end of this console cycle. So, it is normal to expect that we will add new stuff in 2011 and 2012. We're shipping Gears of War now; we're just showing the next bunch of major tech upgrades such as soft-body physics, destructible environments and crowds. There is a long life ahead for Unreal Engine 3. Version 4 will exclusively target the next console generation, Microsoft's successor for the Xbox 360, Sony's successor for the Playstation 3 - and if Nintendo ships a machine with similar hardware specs, then that also. PCs will follow after that.

TG Daily: What part of the engine will need a completely new development?

Sweeney: Our biggest challenge will be scaling to lots and lots of cores. UE3 uses functional subdivision and paths, so we have the rendering thread that handles all in-game rendering. We have the gameplay thread that handles all game-plays and uses AI. We have some hopper threads for physics. We scale very well from dual-core to quad-core, and actually you can see a significant performance increase when you run UT3 on a quad-core when compared to a dual-core system.

Down the road, we will have tens of processing cores to deal with and we need much, much finer grain task-parallelism in order to avoid being burdened by single-threaded code. That, of course, requires us to rewrite very large portions of the engine. We are replacing our scripting system with something completely new, a highly-threadable system. We're also replacing the rendering engine with something that can scale to much smaller rendering tasks, in- and out-of-order threads. There is a lot of work to do.

TG Daily: You already have started working on Unreal Engine 4.0?

Sweeney: We have a small Research & Development effort dedicated to the Unreal Engine 4. Basically, it is just me, but that team will be ramping up to three to four engineers by the end of this year - and even more one year after that. In some way, we resemble a hardware company with our generational development of technology. We are going to have a team developing Unreal Engine 3 for years to come and a team ramping up on Unreal Engine 4. And then, as the next-gen transition begins, we will be moving everybody to that. We actually are doing parallel development for multiple generations concurrently.

TG Daily: Stepping back, what do you see as the most significant technology trends these days?

Sweeney: When it comes to the PC, Intel will implement lots of extensions into the CPU and Nvidia will integrate many extensions into the GPU by the time next-gen consoles begin to surface. We are going to see some CPU cores that will deal with gameplay logic, some GPU stuff that will run general computing... and two different compilers. One for the GPU and one for the CPU. The result will be a reduction of our dependence on bloated middleware that slows things down, shielding the real functionality of the devices.

It would be great to be able to write code for one massively multi-core device that does both general and graphics computation in the system. One programming language, one set of tools, one development environment - just one paradigm for the whole thing: Large scale multi-core computing. If you extract Moore's Law, you see that with the number of cores that Microsoft put in Xbox 360, it is clear that around 2010 - at the beginning of the next decade - you can put tens of CPU cores on one processor chip and you will have a perfectly usable uniform computing environment. That time will be interesting for graphics as well.

At that time, we will have a physics engine that runs on a computing device, we will have a software renderer that will be able to do far more features that you can do in DirectX as a result of having general computation functionality. I think that will really change the world. That can happen as soon as next console transition begins, and it brings a lot of economic benefits there, especially if you look at the world of consoles or the world of handhelds. You have one non-commodity computing chip; it is hooked up directly to memory. We have an opportunity to economize the system and provide entirely new levels of computing performance and capabilities.

http://www.tgdaily.com/business-and...unreal-engine-40-aims-at-next-gen-console-war

It is simply disappointing that Microsoft and Sony both aimed at very low-end CPU performance and very modest GPUs with X1/PS4. I do understand why though. They simply could not justify near-bleeding edge hardware as they did when 360 and PS3 launched in '05 and '06. PS4 and Xbox One had to make a profit from the start.

 

[UrbanRats]

TLOU also employs a neat technique, albeit a little rough, to determine imperfect shadows for characters, cast by indirect lighting which, gives a more convincing effect than typical ambient occlusion methods. I'm still interested to learn how they've achieved that.

I noticed this the other day while playing, i thought it was some form of reflection at first (cause i saw it on a fridge) but then i saw it again on various walls.. very cool effect.

 

[slapnuts]

On consoles maybe. Super smooth on PC.

That is a vague statement considering what hardware is in the particular PC....saying its super smooth on PC is wrong, saying its super smooth on a high end PC is right....most don't own a high end PC. As a PC gamer myself with high end hardware yes it is smooth but the PS4 version holds up very close to a high end PC to be frank.

 

[potam]

I like this thread. I always love finding out just how ridiculous some of these engines are.

 

[Lord_Balkan]

I really like Horizon Mapping. It is pretty fast but requires some extra memory. It allows bumps on surfaces to cast shadows. You get some really cool effect with it.

https://www.youtube.com/watch?v=87EQQlz9X5w

 

[Kinthalis]

That is a vague statement considering what hardware is in the particular PC....saying its super smooth on PC is wrong, saying its super smooth on a high end PC is right....most don't own a high end PC. As a PC gamer myself with high end hardware yes it is smooth but the PS4 version holds up very close to a high end PC to be frank.

Lol. No. Take a look at the pc performance thread. Pretty low end hardware is mopping the floor with the ps4 performance. Trying to equate a ps4 to a high end pc is...delusional.

 

[Graphics Horse]

The clouds in Driveclub seem to be done with raymarched 3D Perlin noise.

There is a web demo of a very similar system here where you can fly around and mess with the parameters here:
http://www.nuaj.net/WebPlayer/
and you can read more about the attempts at creating it here:
http://wiki.nuaj.net/index.php?title=Clouds

The guy who wrote that said he was porting a version of it for Ubisoft Montreal, and it seems it's what's used in AC: Unity's skies as they have a similar look and flexibility.

 

[Kezen]

That is a vague statement considering what hardware is in the particular PC....saying its super smooth on PC is wrong, saying its super smooth on a high end PC is right....most don't own a high end PC. As a PC gamer myself with high end hardware yes it is smooth but the PS4 version holds up very close to a high end PC to be frank.

Mid-range hardware has no issues running the game at better than console settings at >30fps.
You don't need high-end hardware to get better results than either consoles.

 

[Kinthalis]

The clouds in Driveclub seem to be done with raymarched 3D Perlin noise.

There is a web demo of a very similar system here where you can fly around and mess with the perameters here:
http://www.nuaj.net/WebPlayer/
and you can read more about the attempts at creating it here:
http://wiki.nuaj.net/index.php?title=Clouds

The guy who wrote that said he was porting a version of it for Ubisoft Montreal, and it seems it's what's used in AC: Unity's skies as they have a similar look and flexibility.

This is cool. So many games lack good . Looking volumetric clouds.

 

[PLASTICA-MAN]

The clouds in Driveclub seem to be done with raymarched 3D Perlin noise.

There is a web demo of a very similar system here where you can fly around and mess with the perameters here:
http://www.nuaj.net/WebPlayer/
and you can read more about the attempts at creating it here:
http://wiki.nuaj.net/index.php?title=Clouds

The guy who wrote that said he was porting a version of it for Ubisoft Montreal, and it seems it's what's used in AC: Unity's skies as they have a similar look and flexibility.

This doesn't seem. Clouds in Driveclub use Simul Truesky which is a very advanced sky system that handles clouds very realistically in a way that can affect gameplay. For example, the clouds hide the sun for a fertain time and they move making dynamic shadows, and when they expose the sun suddenly you get blinded or dazzled by its beams and you can't drive very well. It can alter stealth games gameplay too: http://simul.co/

You can see driveclub in their site and now they support UE4 too.

 

[Graphics Horse]

This doesn't seem. Clouds in Driveclub use Simulview Trueksy which is a very advanced sky system that handles clouds very realistically in a way that can affect gameplay. For example, the clouds hide the sun for a fertain time and they move making dynamic shadows, and when they expose the sun suddenly you get blinded or dazzled by its beams and you can't drive very well. It can alter stealth games gameplay too: http://simul.co/

You can see driveclub in their site and now they support UE4 too.

Where does their site mention Driveclub? I can't find it
I know about them also and their skies in Arma.