Showing posts with label epic games. Show all posts
Showing posts with label epic games. Show all posts

Saturday, 7 May 2011

Tech Analysis: Gears Of War 3: Multiplayer Beta

Gears Of War 2's multiplayer component, while highly entertaining and incredibly well put together featured some obvious latency issues compared to other high profile online titles. Some matches would go by without issue, while in others you would struggle to maintain aiming accuracy as controller lag impacted on the experience. Since then Epic has listened to these concerns, and for Gears 3 have provided the community with dedicated servers helping to reduce latency to negligible levels.

The gameplay has also been completely overhauled too, now catering for different play-styles via the use of what appears to be a balanced weapon selection (at this stage at least). Close or long ranged weapons part a huge part - often in providing a counterbalance - with players being able to switch between either option at any time. Here, you'll find that someone with a Retro Lancer to be just as deadly as someone with a Sawed Off. It just depends entirely on their own ability and approach in any given situation. The game modes too, have also been reworked and made to be a little more accessible to those unfamiliar with GOW's own brand of multiplayer action.

Of course gameplay and graphics often go hand in hand. The Unreal Engine 3 and Epic's Gears Of War series have been at the very heat of pushing high-end visuals on Microsoft's Xbox 360 console. Not only has the engine been behind some of the most graphically superb releases on the platform, it is also constantly undergoing a range of subtle tweaks and major enhancements.

Gears Of War 2 saw the engine being upgraded to handled bigger environments with longer draw distances - texture and object steaming was refined to prevent noticeable object pop in the campaign mode. Epic also expanded on the lighting component present in the first game and SSAO brought an increased depth to the title's already decent use of shadowing.

Even in it's current stages as a mutiplayer beta, Gears 3 demonstrates similar leaps in visual quality, with upgrades in a variety of different areas. Perhaps the framebuffer is the only thing exempt from this, but in any case image quality was never really an issue to begin with.



For the record, you're looking at a native 720p rendering resolution forgoing the use of anti-aliasing. In past titles, AA was performed pretty early on in the rendering cycle, meaning that it had pratically no impact on the final scene being rendered. Sampling was only done on static objects and lighting, thus additional post processing elements - such as depth of field, bloom etc - and dynamic lighting weren''t covered by the limited use of MSAA at all. So as a result Epic has disabled the use of edge-smoothing completely, perhaps in order to maintain more consistant performance while the game benefits from a range of graphical improvements.

The lack of AA means that we find a variable level of jaggies and shimmering edges. Stages featuring copious amounts of sub-pixel elements suffer the most, whilst areas with mainly large geometric structures fare much better. This is of course in line with most UE3 titles, and in the case of Gears 3 can be considered a worthy trade-off considering number of HQ components in the game's rendering tech. It's also worth pointing out that aliasing is less noticeable overall than it was in Gears 2.


Looking back at past titles, it was the single player campaign that trumped any of the multiplayer modes graphically. And it's very likely that we'll see a similar kind of visual leap again with the campaign in Gears 3. The current beta exceeds past instalments in most areas, which leads us to believe that Epic have even more visual mastery packed away under the hood.

Compared to Gears 2, the various upgrades come in thick and fast. At the base level we see more detailed character and environment modelling, both in texture work and in geometric complexity. Little cracks and other small details that feature on the surrounding environmental stonework are more distinct than before. In particular, the depth of the parallax mapped floors have even more of an impact, even if they do look just a little too OTT as a result.

There a few obvious low resolution, and repeated textures dotted about, along with some rather flat looking surfaces. But these do very little to spoil the over look of the game considering how detailed the environments actually are. The leap in quality is huge compared to Gears 2's multiplayer mode, and even exceeds the single player campaign portion of it with ease.

Additionally, there is little in the way of harsh LOD transitions at the beginning of each match. In Gears 2 there was a tendancy for the engine to still be streaming in final quality assests for at least a minute or two after matches had begun. But thankfully, we see that this issue is pretty much non-existent in Gears 3.


The biggest change however, comes in the form of the game's lighting system. Like with the likes of Crysis 2 and Battlefield 3, Gears 3 features its own implementation of global illumination via Epic's Lightmass solution, which provides a cheap alternative to the few real-time GI systems doing the rounds right now (Geomeric's Enlighten for example). Ambient lighting, along with the main light bounces are rendered off-line before being pre-baked onto the environments, thus providing a similarly realistic look but without the raw processing costs usually associated with doing this.

Dynamic lightmaps ensure that the lighting data actually affects moving objects in real-time, rather than having no impact whatsoever. Given the fact that the sun's position never changes, by far the most important factor is believably lighting up the various dynamic objects present in any given scene - lighting that never moves can be convincingly baked, so long as it still affects environmental objects in real-time. And the implementation found in Gears 3 manages to do a excellent job in this regard.


We also see that sunlight now casts dynamic shadows off select objects, further enhanced when combined with the game's pre-baked shadowing components. Other elements that give off light - such as gunfire and explosions, burning parts of the scenery etc - react with both the environment and the objects contained within. Although they did this in Gears 2 as well, the effect is more refined in this sequel.

Even if the baseline environmental lighting is static, the combination of dynamic lightmaps and additional light sources help breathe life into the way in which scenes are lit and shaded. The difference is dramatic to say the least; there's a whole lot more depth added to the scene over the previous games.



Outside of Lightmass, and there are a few other nice touches that Epic have made with the lighting engine in Gears 3. A probable FP10 buffer, and a controlled use of bloom substitutes true HDR lighting without over-emphasising the top end of the spectrum, while the game now features stronger use of simulated godrays (they are simply a post process-based effect). As you can see above, in some stages sunshafts dynamically react with the environment, while in other areas they are more static in nature.

Additionally, the way that SSAO is handled has also been tweaked slightly. SSAO is done as a post process in both GOW 2&3, with it being reprojected and accumulated over multiple frames. The end result is that it could appear more noticeable in still scenes in GOW 2 than when moving. In Gears 3 however, the temporal side effects have been reduced, and there is now greater consistency in deploying the effect throughout the scene.


In terms of alpha-based effects, smoke in particular features convincing depth being heavily multi-layered, while also appearing volumetric. Particles, fire and smoke look much fuller than they did in Gears 2. The way in which they interact with the surrounding geometry is almost bug free - you can see clearly in the shots below how the smoke collides with the nearby walls, rather than simply clipping through them. Alpha buffers are also rendered in full resolution, taking full advantage of the high bandwidth eDRAM present in the 360's Xenos GPU.



Moving on, and when looking at the online element in any game the importance of having a consistent frame-rate is paramount. It's not so much about ensuring you have a visually smooth experience (though that certainly helps), but instead one with as little controller latency as possible. Essentilaly the two do go hand in hand, but with previous Gears games this was limited by the lack of dedicated servers, thus introducing additional latency outside of the game slowing down.

Although it's likely that we'll see greater variation in performance during the single player campaign, due to the engine pushing much larger environments and more stenous action, in the beta Epic has done well to keep things under control in order to deliver as little input lag as possible. And this is something that has further been addressed by the use of dedicated servers. In the beta not everyone will be on dedicated servers at all times, although performance on these alternate hosts is improved compared to the ones powering GOW2's online component.



Performance-wise, Gears Of War 3 operates at 30fps and employs v-sync in order to maintain image consistency. However, we also see that v-sync is disengaged when the frame-rate drops below 30fps in order to maintain a steady level of performance in scenes which stress the engine. To that effect there is some barely visible tearing that manifests by crawling up and down the screen, which can frequently occur during gunfire, but its impact goes reletively un-noticed for the most part.

While the game manages a stable frame-rate for extended periods of time, there are a few drops in smoothness to speak of when the engine is put under stress; mainly in scenes whereby multiple players are present and lots of gunfire and explosions create additional load. But outside of these scenarios there is little in the way of slowdown to impact on the experience, which also ensures a crisp controller responce is maintained as often as possible.

Also, like with many games this generation (Alan Wake and Vanquish both spring to mind) GOW3's smooth refresh rate is further enhanced by the inclusion of motion blur. Going back to the first game and the Gears series has always used a vector-based motion blur implementation, but this is now handled on a per-object basis. As you can see below, the effect varies in strength - ranging from rather subtle to in your face as it were, producing a nice screen distortion effect in the process - but also serves to seamlessly blend individual frames together to create a more fluid screen refresh.



Overall, even in its unfinished state as a multiplayer beta, Gears Of War 3 is clearly shaping up to be another noteworthy graphical showcase for the 360. Sure enough, the real test of course, will come in the form of the single-player campaign, in which larger environments and distinct set-pieces are likely to push the engine a lot harder than anything we've witnessed thus far. But for now things are looking rather promising, with Epic successfully using its underlying tech to craft a suitably lavish visual experience. Going back to Gears 2 and then to the beta, and there's a real tangible difference to be felt in the overall quality of what we are seeing.

Coming away from the look of the game and there is also a sense that Epic are trying to further hone in Gears Of War 3 as a distinct online experience, separating it from past titles and from other online shooters in order to keep things fresh. Not only is the gameplay faster, but the close/ranged set-up for example, seems balanced enough for players to compete on an even keel regardless of their play-style, while the skillfully deployed weapon placements ensure that mastery of the maps themselves, and the calculated strategy that goes along with them isn't lost to those more inclined to simply run and gun their way to the top.

Tuesday, 7 September 2010

Tech Report: A Look At Epic Citadel

With the impressive specs of the recent iPhone 4, along with the iPad and iPhone 3GS, we always new that Apple’s stylish little handhelds had tantalizing potential that seemed destined to be unlocked at some point. The question was whether or not the system’s slightly limiting development environment, in combination with the high development costs in creating graphically fully featured releases would prevent such a thing from ever happening. With Epic Games’ Epic Citadel Demo a glimpse of that potential has been realised, finally showcasing just what the iPhone range of Power VR SGX GPU’s can do.

This is probably the first time that we have seen anything that pushes Apple’s mobile devices in such a way, as although titles such as Epic’s own Doom Resurrection, and Capcom’s Resident Evil 4 looked good, they were far from demonstrating what was really possible. Despite this, the Epic Citadel demo whilst appearing very impressive is actually not that technologically advanced, featuring very few high-end shader effects and a lack of heavy dynamic lighting – something usually found in UE3 games. It does look very good however, and makes the point that having good art is sometimes more important that having the most advanced tech.




The above screenshots show the game running on an iPhone 3GS (pinched from a friend while on lunch) and are easily above original Xbox quality. The level of texture detail is incredible for a handheld device, looking far better than anything we have seen on either the PSP or even Nintendo’s 3DS, and the subtle but pleasing inclusion of some basic dynamic lighting, plus additional tone mapping brings a sense of depth to the image.

More impressive still is the use of a very cleaver LOD system, which means that pop up is never as intrusive as you’d expect when looking upon far away areas, and that the high levels of detail effectively remain on screen for longer.



The iPhone version of the UE3 only supports the use of OpenGL ES 2.0, thus only working on the latest models of the device. Although it’s not just iPhone 4 users that will benefit from this upgrade in graphical quality with titles that use the engine. The demo even manages to run smoothly on the older iPhone 3GS or iPad whilst either missing, or simply toning down specific visual effects.


iPhone 4


iPad


iPhone 3GS

On the 3GS that I used to sample the demo, the framerate largely hovered around the 30fps mark, only really dropping down in areas where lots of detail is visible in wide open spaces. In these areas the framerate can, and will frequently drop down to around the 20fps mark, whilst also introducing some serious input lag that temporality ruins the otherwise responsive controls.

Available memory, and memory bandwidth for the GPU seems to be the main issue here, as does GPU clock speed – it’s faster in the iPhone 4 compared to the 3GS and iPad. However, even with these small cutbacks in visual fidelity Epic Citadel is firmly above other titles on either device, and represents just the kind of visual step forward we could be seeing in future titles.



Outside of the highly polished nature of the demo’s texture mapping, and filtering providing us with lavish image quality, and the subtle inclusion of dynamic lighting (backed up by a custom lightmass GI baking solution), there isn’t much that is all that technically impressive - Specular reflections are hardly new even if the still look great. Most of what makes Epic Citadel look so good comes down to using high quality art assets, and good overall art in general – both of which are lacking in most current iPhone releases.

This is especially true for games running on lower spec platforms. Some of the most impressive looking PS2 titles used good art to simulate far more advanced effects without the means to do them natively, thus holding up against their Xbox counterparts.


Of course, increasing the quality of the art assets used takes both time and money, and one of the reasons that we haven’t seen such high production values in a iPhone game yet is largely down to the software market that it will be entering into. Most titles sell for less than £7 on the AppStore, even less than £3 in many cases, meaning that it will be harder for developers to claw back the increased costs involved of embarking on higher-end projects. And the risks may not be worth the rewards.

However, at least the option is now wide open for software houses to choose, and it’s likely that getting your game up and running using a decent middleware solution like UE3 is far easier than developing your own advanced, fully custom iPhone engine. The real question is whether or not it circumvents enough of the additional development costs incurred by significantly ramping up your art assets. But that is something that can only be answered by individual publishers themselves, and until then, all we can do is watch, wait, and see what happens.

Thursday, 15 April 2010

Tech Report: Gears Of War 3 Teaser Trailer

With the Gears Of War 3 trailer finally unveiled yesterday, along with a splattering of pre-release information and interesting technical facts, we though it was time yet again to bring about another tech report. This time we’ll be focusing on this week’s teaser trailer and talking about the visual enhancements planned for the title, what they mean and how they could be included when it comes to the final game.

Currently there isn’t all that much to go on. Outside of the trailer - which we’ll be analysing in a moment - only a handful of new graphical features and visual effects were mentioned, and of course the intention to further optimise the title for the 360 architecture. However today’s IQGamer report will be just the first of many, and we shall be updating you every step of the way as new information surfaces. It will be interesting to see how the first in-game shots really stack up to Gears 1 & 2, and how many of the cut visual effects from the second game make it back in, if they in fact do so.


In terms of new graphical effects, Epic Games plan to include a global illumination system in Gears 3, along with indirect lighting, an intentional side effect of GI, and increased amounts of particle effects and specular highlighting. Other undisclosed improvements to the overall game engine are also being coded into the latest version of the Unreal Engine 3, mostly in the way of optimisations with regards to existing features found in the tech.

The first of these, a form of global illumination, is a technique in which a single light source reflects and bounces off every surface it comes in contact to. And whilst something that advanced isn’t going to be possible on the 360 in its entirety, a semi-real-time, pre-calculated approach is certainly on the cards.

The second is that as a result of the inclusion of GI, we can expect there to be a lot more in the way of indirect lighting, a side effect from the light bouncing off one source and providing lighting for another. This in turn will create better ambient lighting relying less on pre-baked shadow and light maps, more dynamic in nature, hopefully being done in real-time, of half real, half pre-baked for an effective but cost saving (resource wise) approach.

Both of these effects should go a long way to increasing the sense of depth and realism into the experience, at the same time complementing the use of baked ambient occlusion and shadow maps nicely.


Looking at the trailer itself it’s pretty clear that a few of the new effects, such as indirect lighting and improved specular highlighting are visible. Although there doesn’t appear to be any sign of the GI solution they mentioned.

The trailer seems to be rendered using in-game assets and the actual in-game engine, though it doesn’t appear to have been done in real time. Much like with the first Gears 2 trailer there appears to have a higher image quality compared to both of the first two games, with better texture filtering and less noticeable aliasing. However the trailer also shows off a few low resolution textures and still doesn’t feature a useable MSAA anti-aliasing solution, meaning that in all likelihood it is a genuine in-engine rendered, which could well be matched in the final game. The trailer looks like it’s being rendered in 1080p and downsampled for AA, rather than having actual MSAA for jaggies reduction.

You can also see much greater texture detail as well compared to before. Characters now have facial hair which has a sense of depth about it rather than being just a flat texture. This is done through the use of shader techniques in combination with normal mapping, which seems to also have been improved over Gears 2. Geometry counts looked to have been upped slightly too, which would explain, along with the shaders, how a lot of that extra detail has been included. I would imagine that whilst some elements have less geometry than in previous games, due to better shader usage, other areas of the game would have benefited from a slight increase in order to give more detail.

The use of shadow maps and baked ambient occlusion appears to be present, with the AO looking to be more prominent than before, and the shadow maps creating contrast to parts of the environment not being directly affected by the game’s lighting system.


The above screenshot shows off clearly most of the new graphical effects that were mentioned earlier on. For example there is an abundance of particle effects on screen being kicked up the giant Locust boss character, and everyone from the Gear’s themselves to the standard Locust enemies have more sheen and a smoother look generally provided by better specular and diffuse maps.

Like with Gears 2 the gunfire lights up the environment surrounding the characters, although this time its reach is greater than before, reacting with increased intensity with environmental specular and diffuse maps. In addition the lighting from above the clouds also creates subtle light and dark areas on the ground, encasing characters in shadows and light as the clouds move and pass over them.

Whilst it isn’t possible however, to see any of the indirect lighting that Epic has stated would go into the game, the overall basic lighting and shadowing model has seen noticeable improvement over the first two games. With GI and indirect lighting it should look even better, even though the implementation is likely to be a simple one in order to maintain engine performance.

So far, whilst it looks better than previous the early trailers and tech demos for Gears 2, this Gears 3 trailer only scratches the surface of the improved lighting, although both the particle effects and shaders have seen significant improvements. The GI solution that Epic are working on for the title should make all the difference, and as long as they keep the image quality increases shown in this trailer we should be expecting another technical showcase for the 360.

Well, that’s all we know for now, and everything we can establish from the very short and hardly revealing teaser trailer for the game. Some of the things we pointed out weren’t exactly new to the series, but simply refinements to an existing graphical base of the Unreal Engine 3. As development progresses we expect to see much more in the way of improvements, mainly in the form of the GI lighting, and hopefully a proper anti-aliasing solution as well.

Either way this short little demo already looks to have better tech than in Gears 2, and all that remains to be seen, is how well Epic will do in keeping all the features introduced in forthcoming trailers in the actual final release build of the game.

IQGamer will be following the progress and development of Gears Of War 3 closely, with more tech news and analysis as it breaks.