Scalability of ND's Uncharted engine *spawn

[Rotmm]

Mod: This thread is spawned from the Uncharted 2 game thread. Now it's on the tech forum, standards will be raised!

In Uncharted 2 though, you don't have the open exploration, but on the other hand, you get to visit so many very different places and get a great diversity in the visuals. From snowy locations, cities, temples etc. I don't think you could combine all of this in an open world if you wanted it tied to a realistic setting.

It's also true that the reason some of the vistas are so impressive is precisely because the game isn't open world and you can't actually go into those beautiful locations.

 

[patsu]

Or rather, you can't go from point A to point B on your own. We do get to visit those beautiful locations in Uncharted 2 (indoor, outdoor, underground in snowy locations, cities and temples, etc.). It's not just the vista. Closeup looks good too.

 

[Rotmm]

Closeup looks good too.

Indeed. However, my point is that access to the world is very closely controlled, so the game sometimes gives you the feeling of being in a bigger area with those luscious vistas, while in reality you are still running along that narrow (and still good looking ) path, giving the devs the ability pack detail into those environments.

 

[Phil]

It's also true that the reason some of the vistas are so impressive is precisely because the game isn't open world and you can't actually go into those beautiful locations.

I wouldn't be so sure on that. I think the engine could handle an open-world but that would certainly mean that more effort would have to go into asset creation and it maybe a bit tricky to get the story going (players could get lost more easily).

I was under the impression a lot of the loading is done during the 'pre-rendered' cutscenes. I was very impressed to find out that you can skip every single one of them (well each one I have tried to far on my second play through) and have the game continue immediately without any loading screen at all. A nice example is skipping one of the first cutscenes once you find the phurba and immediately continue in the flash back of Istanbul which is an entirely different setting. When and how did they stream that data? And there isn't any HD install either...

 

[Arwin]

When and how did they stream that data? And there isn't any HD install either...

When you were playing the previous level. Towards the end of the previous level the game will be starting to stream in the next environment (mostly from BD to HDD I believe, and only to RAM as soon as space gets freed up there). You'll get a loading screen only if you boot up the game, go straight to that chapter and then skip the cutscene, because then the game hasn't had a chance to stream the stuff in.

 

[Cornsnake]

Uncharted 2 looks like it's levels are completely designed around it's streaming tech. Your constantly climbing ladders, giving a boost up, dropping down ledges, or going through a linear platforming sections. They always make sure you can't go back or at least not quickly. That should more easily allow them to remove the last section out of memory, and start streaming in the next.

I could be wrong about this of course. Maybe Digital Foundry can take a better look at how their streaming tech works.

 

[Kittonwy]

The levels in the game are actually pretty big, with the player almost always able to control the camera, and there are often places where the game is basically rendering gigantic vistas, not to say the game doesn't do culling but at 1.2 mil triangles per frame, it's not like they rely purely on cheats, if they want to make an open-world game with their tech they probably can, their tech is probably way more mature than the one Sucker Punch worked with, afterall the ICE Team is right there in their studio making the very tools the rest of Sony developers use. One of the things that I was amazed was when I shot at the helicopter, the missile pods would break off, and they were real physical parts that would land on rooftops and can be affected by physical interactions, they weren't super high-res but I was surprised I actually found them, I was more often impressed by how often they don't cheat.

 

[Laa-Yosh]

Those huge vistas are always of such areas that are completely unreachable for the player. Thus the detail levels can be as low as possible to get away with... It's certainly not like the giant cities in Assassin's Creed and GTA 4, or some of the larger areas in the Halo games.
So UC2's vistas can look significantly better then these games, too.

Don't get me wrong, I'm not trying to bash the game here - I think it looks wonderful, and is probably as good as people say. But let's not forget that Naughty Dog has made some compromises too, just as any developer.

 

[Shifty Geezer]

Those huge vistas are always of such areas that are completely unreachable for the player. Thus the detail levels can be as low as possible to get away with...

I don't quite understand this. One would hope LOD would drop down the detail of far-away places. Then when you get there, the game fills in all the details. This seems to me to be a matter of storage and labour rather than technical achievement.

Unless you mean the unreachable places promise a complexity that isn't attained in game. eg. We see some awesome city territories, but not forests (say. I haven't played U2!). So if the distance shows a rich jungle and yet there are no jungle experiences in the game, we can expect the engine can't handle jungles, and the distant vistas are kept away so the developers woudn't need to worry about handling jungles in their engine. If that makes any sense.

 

[Kittonwy]

Those huge vistas are always of such areas that are completely unreachable for the player. Thus the detail levels can be as low as possible to get away with... It's certainly not like the giant cities in Assassin's Creed and GTA 4, or some of the larger areas in the Halo games.
So UC2's vistas can look significantly better then these games, too.

Don't get me wrong, I'm not trying to bash the game here - I think it looks wonderful, and is probably as good as people say. But let's not forget that Naughty Dog has made some compromises too, just as any developer.

Even in Uncharted 1 they have vistas like the german sub that the player CAN reach, the whole open area where Elena's parachute landed the player can literally go anywhere. Uncharted 2 is very similar in that if you can see the area eventually you'll get to it, the only difference is that it's not go-anywhere because it's not an open-world game. The geometry is there, shoot down a missile pod during the helicopter fight and if it lands on a certain piece of geometry, it stays there, it doesn't matter if it's down on the street or if it lands on a rooftop, if you happen to come across it, you can even stand on it and interact with it.

HALO games have never been completely open-world, even ODST loads up a new area everytime you get to a door.

All those games use LOD heavily, and you can't interact with any distant geometry until you're physically there, AI and objects don't get streamed in until you're close enough. Every game makes some form of compromise but for a linear experience, Uncharted 2 surprisingly retains a lot of the persistence and interactivity.

 

[patsu]

Yap, some play areas in U2 are not small. The added vista is just gravy on top.

 

[tha_con]

Those huge vistas are always of such areas that are completely unreachable for the player. Thus the detail levels can be as low as possible to get away with... It's certainly not like the giant cities in Assassin's Creed and GTA 4, or some of the larger areas in the Halo games.
So UC2's vistas can look significantly better then these games, too.

Don't get me wrong, I'm not trying to bash the game here - I think it looks wonderful, and is probably as good as people say. But let's not forget that Naughty Dog has made some compromises too, just as any developer.

What makes you think ND couldn't achieve significantly better? It's pretty clear their LOD is a bit more advanced than the average bear's...

I'm not really following you here, at all.

 

[Neb]

Those huge vistas are always of such areas that are completely unreachable for the player. Thus the detail levels can be as low as possible to get away with... It's certainly not like the giant cities in Assassin's Creed and GTA 4, or some of the larger areas in the Halo games.
So UC2's vistas can look significantly better then these games, too.

Don't get me wrong, I'm not trying to bash the game here - I think it looks wonderful, and is probably as good as people say. But let's not forget that Naughty Dog has made some compromises too, just as any developer.

Clever use of LOD. There was a screenshot posted previous in this thread with fairly large vista over the water, mountain and vegetation. And it looked good however not being accessible and being still shot it was obvious trees where flat sprites very very close up. Yet the image looked quite uniform. I guess prebaking lighting and shadows for non-reachable parts are also something to make thigns prettier.

 

[Laa-Yosh]

What makes you think ND couldn't achieve significantly better? It's pretty clear their LOD is a bit more advanced than the average bear's...

The vistas aren't using any LOD at all, they're made at one level of detail - because you, the player, won't be able to get any closer to them. You're always constrained to a relatively thin path.

Again, this is not bashing, it's just pointing out that there are compromises and UC2 choses one kind over the other, that's used in free-roaming games (which have significantly blander looks, but you can explore almost everywhere).

 

[phat]

The thing is, ND's engine seems perfectly capable of handling the same amount of detail density in the vistas as in the foreground (but obviously with reduced LOD when viewed as a vista). The ability to render a world seamlessly, monolithically, with uniform detail density throughout makes the engine ideal for open-ended gameplay. Other games have done more open-ended with much weaker engines.

Of course, the burden of asset creation will increase if the player is allowed to roam freely...

 

[PhilB]

The ability to render a world seamlessly, monolithically, with uniform detail density throughout makes the engine ideal for open-ended gameplay

The levels are mostly narrow and tightly controlled. Obviously they could make an open ended game but there'd probably be significant changes in visuals (depending on how much thy rework the engine).

 

[Laa-Yosh]

The thing is, ND's engine seems perfectly capable of handling the same amount of detail density in the vistas as in the foreground (but obviously with reduced LOD when viewed as a vista).

I have to disagree here... there are many aspects of the game world that are drastically different this way, it has an effect on streaming level data, rendering shadows, handling visibility and occlusion, and so on. There's a reason we don't get games on the current gen hardware that have this amount of detail and variety in a large and completely open world - it's just not possible to do...

 

[ultragpu]

I have to disagree here... there are many aspects of the game world that are drastically different this way, it has an effect on streaming level data, rendering shadows, handling visibility and occlusion, and so on. There's a reason we don't get games on the current gen hardware that have this amount of detail and variety in a large and completely open world - it's just not possible to do...

I believe the reason why open world games like Assassin's Creed II doesn't look as detailed is due to the significant increase in NPC AI. Last time I heard AI was really processing intensive and so resources must be sacrificed. Whereas in Uncharted 2's case you don't see that many NPC AI roaming around and the setting is perfectly suited for that reason. Perhaps that's why ND has the extra juice on visuals. Besides, take roof top level for example, you see the 360degrees vista and they're obviously rendered all in 3d, you get more interactions with the scripted events and buildings due to the pacing and story. Like Shifty said, if more labour is dedicated to other corners of the level then I don't see any reason why it won't be accessible. Maybe it won't be as seamless as a true open world game but ND hides the loading nicely with cutscenes and that's good enough for me.

 

[Kittonwy]

The levels are mostly narrow and tightly controlled. Obviously they could make an open ended game but there'd probably be significant changes in visuals (depending on how much thy rework the engine).

The player path is tightly controlled but a lot of the playable levels are quite large, especially some of the rooftop sequences the player can actually see a lot of the places he has been or will reach, and because of the free camera, lots of actual geometry must be rendered.

 

[Laa-Yosh]

I believe the reason why open world games like Assassin's Creed II doesn't look as detailed is due to the significant increase in NPC AI. Last time I heard AI was really processing intensive and so resources must be sacrificed.

Oh come on, AI hasn't got much to do with texture memory limitations and storage issues (loading a huge game world and keeping it in memory).

It is a resource issue first and foremost, and performance is secondary here. Granted, raycasting for AI sight gets more computation heavy as you increase the scenery poly count, but it isn't such a bottleneck.
Just look at GTA4 where you can literally go anywhere and have to keep a huge city at some detail level in memory with all its components. Then compare it to UC2's city where there's a limited path you can follow, with only a few buildings in sight that you can ever interact with. The game also knows the direction you're allowed to proceed through that city so it can preload data only when it's needed, when you're just around the corner. Clever construction of the level can hide parts that aren't loaded yet. And so on and so on.

It's smoke and mirrors, but it works perfectly well and looks very nice.