Sunday, 19 December 2010

Tech Analysis: Uncharted 3: Teaser Trailer

So, Uncharted 3 has finally been unveiled. And for those who didn’t think this generation of consoles had much more to offer graphically… well, Naughty Dog’s latest – still just under a year a way from completion – definitely looks to silence the critics. Arguably, given the quality of the real-time and in-engine rendering on offer in Uncharted 3, there’s no need to hurry along to meet that five-year hardware lifecycle.

At the recent VGA awards Naughty Dog finally blew the lid off the next title in the globe-hopping, bandit-shooting Uncharted series, with Drake once again looking rather worse for ware, but this time stranded in the desolate Arabian desert.

The trailer showcases a variety of engine improvements, from shadows and lighting, to texturing and skins shaders. All have seen a noticeable upgrade. Some of these look to be suspiciously from in-engine - but not in-game - footage, whereas others look to have taken the actual in-game tech another leap forward (just look at those water effects). Either way, Uncharted 3 at this early stage looks absolutely incredible.

The trailer can be divided up into three distinct parts; the desert scene in which we see Drake walking slowly across some sand dunes, stranded after being involved in a plane crash; a scene in which him and sully are in a darkened room in what looks like a flashback of sorts; and the ending post title footage, which clearly shows off a few short seconds of actual ganeplay.

All three can be seen below for comparison purposes, and it’s here that we can see exactly which parts of the trailer are being rendered in-engine, in real-time, and actual gameplay.

Starting off with the desert scene, and we can see most obviously some of the changes Naughty Dog have implemented in their engine for Uncharted 3. Drake himself has been remodelled, his facial features adjusted to represent an older, rustier, heavily warn adventurer. He looks almost slightly chubby in appearance. But look at his arms and legs through his clothes, and we can see that it’s just his underlying bone structure that has been updated.

Texture detail has been noticeably upped. Even from the highly compressed video footage we can see additional subtleties in the form of wrinkles, stubble, and pores on the skin. Skin shaders too have also seen similar increases in quality, with all those little facial features reacting far more realistically with the game’s environmental lighting.

You could say that it looks almost too good to be in-game… and indeed it is. This second opening scene looks like it has been created using in-engine assets, though not rendered in real time. A few things other than the shaders hint at this. Most notable the composition of lighting and shadowing in the scene as a whole… they’re largely flawless in their execution.

The shadowing model in particular is completely artefact free whilst maintaining an incredibly level of precision and accuracy. Notice how both the environment and Drake’s own self-shadows lack any kind of jittering or mostly any edge shimmering, both of which are present in later parts of the trailer and in Uncharted 2. All shadows, both up close and far away, are perfectly cast without error, carefully adding a great deal of depth to the final image.

The lighting also complements this, with dynamic shadows reacting and changing according to the environment conditions. Shadows are cast where expected, and the shader model delivers reflections and subtle changes usually too computationally heavy to be replicated with such precision either in-game, or in real-time in-engine cut-scenes.

Although saying that, the art assets used in the trailer are all ones that will be used during gameplay according to Naughty Dog; they’ve simply upgraded some of the effects to complement the offline nature of rendering the scene for the trailer. It’s purely an artistic style choice, great for PR screenshots and posters, but not all that far off from what is present in game as it were.

There are other things that also point to this fact, the detailed nature of Drake’s attire for example. Everything from his belt, the bullets situated upon it, his shirt, and his scarf are beautifully rendered. In particular, Drake’s scarf seems to have a soft-cloth simulation of sorts integrated into its animation system, with no polygon clipping or edge and shadow artefacts. It’s like a CGI rendering but using in-engine artwork.

In terms of the actual trailer resolution, it appears that different scenes are rendered in varying original framebuffer sizes before being either upscaled or downscaled to form the final 720p image. Take the opening desert scene for example. Here we have what looks like a 1980x1080 original FB which has been downsampled in a process known as supersampling to deliver large amounts of full-scene anti-aliasing, resulting in very little in the way of jagged lines.

In fact, the aliasing that is present in this scene – shadows and subtle edge aliasing from certain angles, along with texture aliasing – is perhaps more down to shader aliasing and in particular, the lightsoures being used in combination with the resolution of the shadowmaps themselves. Also, there is barely any evidence of subpixel aliasing issues - we can see that thin lines and small pieces of geometry are highly smoothed over – a key component of using supersampling. But there is nothing more than a few edges with ‘soft jaggies’ standing out from the rest of the scene.

On the whole, this centrepiece scene from the trailer comfortably represents the kind of graphical upgrades to be expected throughout the actual game on a baseline level, although shader effects and texturing has obviously been increases slightly beyond levels possible in-game in real-time no less, with additional precision along with more detailed character modelling.

Moving on to the second key scene, and we can see similar engine upgrades taking place, but without the same level of perfection as in the desert portion we’ve discussed above. Both Drake and Sully feature improvements in texturing, normal mapping and shaders, but not to the extent as seen in the ‘in-engine, pre-rendered’ part of the trailer. This scene appears to be rendered not only with in-game assets but also being done in real-time without any of the ultra precise shadowing and lighting.

Obviously like for like comparisons aren’t completely possible – different lighting conditions and the fact that Drake himself looks to be younger, slimmer than in the earlier part of the trailer – although we can still see evidence of visual tweaks and changes while also spotting a few rendering artefacts that reveal the scene’s real-time presence.

Take a close look at the shadowing on Drake for example. Some of the self-shadows evident around his neck clearly show evidence of jittering and some edge shimmering – something larger absent from the desert part of the trailer. In addition Drake’s character model is slightly less detailed, with reduced shader effects and subtle texture details.

Like with the earlier scene, this part of the trailer also appears to be rendered in 1920x1080 before being supersampled down to 720p, which would explain the lack of any noticeable edge shimmering on the geometry. Although, in dark low contrast environments such things rarely manifest themselves.

Onto the actual gameplay portion of the trailer, and this is where things get difficult. The short and chopped up, cropped, and constantly resizing nature of the clips, along with compression induced motion artefacts make it difficult to assertain how close the game holds up to the graphical quality of the cut-scenes in any meaningful way.

However, we can at least see that the quality looks about on par, or close to the scenes in question. Much like in Uncharted 2, the cut scenes do appear to be higher quality renderings, though using in-game assets and running in real-time (assuming the same system from Uncharted 2 is in place, whereby all cut-scenes are real-time and not video recordings of the renderings). I imagine that gameplay will look basically the same to the untrained eye, featuring similar rendering bugs, but with a touch more detail and precision.

This part of the trailer also looks to be rendered in native 720p (1280x720) like with previous Uncharted titles, while anti-aliasing is yet to be determined. Some have said that MLAA looks to have been implemented, though with compression artefacts masking any potential aliasing issues and the clips so short/poor in quality, this may just be wishful thinking at this point. However, we shall be taking a look at the more recently released direct-feed gameplay video to investigate this further.

One thing that does stand out with the gameplay footage, is the noticeable upgrade in the engine’s ability to render water and fire effects. The water in particular looks incredible. It almost looks like a simulation if you don’t pay attention to how it flows and changes in motion.

The main body of the water appears to be more volume-based than particle-based - modelled with large mesh of animated geometry and normal maps - thus avoiding the PS3’s limited available memory bandwidth for alpha effects, although this is indeed backed up with some particles at the front as the water expands and spreads across the environment.

The fire effects also feature more animation than those found in uncharted 2. From the brief few seconds of footage, we can see an increse in the layers of 2D sprites used to form this effect, with greater levels of blending. Although, again… it’s pretty hard to tell, given the quality and duration of the footage.

Instead, a far better example of how Uncharted 3’s gameplay will hold up against both the in-engine pre-rendered parts of the trailer, and with the real-time in-engine cut-scenes can be found here, in the first direct-feed gameplay trailer.

As you can see, there is a noticeable difference between both the character and environment modelling, shader effects, shadows and lighting compared with the trailer. Against the standard cut-scenes too, we can see a slight downgrading - small, but perhaps greater than the differences in Uncharted 2.



We’ll be taking a look at the gameplay trailer in the next day or two at IQGamer in a shorter tech analysis, mainly focusing on the upgraded fire effects and comparison details between pre-rendered in-engine footage and gameplay. Interestingly, these gameplay shots feature very little in the way of aliasing, shimmering edges etc, which could lead to either an MLAA solution being implemented, or perhaps more supersampling - used in creating print and promotional quality bullshots. But we shall see.

In the meantime we can at least see that regardless of how the footage – and indeed the screens – have been enhanced, modified, or created from an offline render, that Uncharted 3 is already delivering a tangible improvement in rendering quality over and above Uncharted 2 and in some respects Killzone 3, while the game still has just under a year to go before it goes gold.

We also haven’t even mentioned that 3D support is also in the pipeline for day one. How this will be implemented – what method: side by line, top to bottom, half res, full res, etc hasn’t been confirmed – but Naughty Dog have stated that the engine is constantly in a state of flux, with new tech and changes being implemented right up until a month before the final crunch to completion. With that said, we won’t likely find out anything concrete for at least a few months. Although details on the 2D rendering engine will certainly surface long before that.

So… Uncharted 3 then, from what little we’ve seen of it, is looking mightily impressive at this point. It’s very early days in the game yet, with many questions still going unanswered, and a few in which the answers are obviously identifiable. The leap between the second and third Uncharted titles doesn’t appear to be as gigantic as the jump from UC1 to UC2 (SSAO was by far the most noticeable upgrade), although there’s plenty of subtle elements that provide additional flair to the engine, along with increased levels of realism to help engross the player further into Drake’s world.

As we’ve already mentioned, a direct-feed gameplay trailer has since been released to complement the highly directed teaser trailer, showing off two minutes of continuous gameplay in which to present the various in-game engine improvements. You can expect another analysis, albeit much shorter based on this in the next few days.

Thanks go out to Nebula for the framebuffer analysis/pixel counting.

No comments:

Post a Comment