Tech Analysis: Assassin's Creed: Brotherhood (PS3 vs 360)

There has always been quite a considerable gap in between the PS3 and 360 versions of previous Assassin’s Creed titles. Whilst most of the core make-up of each game was in fact pretty much identical, sans occasional differences, both performance and image quality lagged behind on the PS3. So much so that Ubisoft themselves ublicly recognised this, with Level Design Content Director, Phillipe Bergeron, acknowledging that more could be done in a recent interview with IGN.

"At the end of ACII we realised that the PS3 was sort of an afterthought – or, not that it was an afterthought, but we hadn't fully debugged it until the very end, and we had a bunch of frame rate issues and quality issues. This time around we knew that, because we went through it once, so we decided to attack it from the beginning and I think the final product is much more on the level, and even on some parts, the frame rate is probably sometimes better on the PS3 than it is on 360."

The question is though. Did Ubisoft Montreal actually follow through, or are we left with another disappointing PS3 port, complete with noticeably worse performance and a smeary Vaseline-styled look? The answer in fact, may just surprise you. As although Assassin’s Creed Brotherhood shares much with its predecessors, it is certainly a more polished affair in which the PS3 version stands up remarkably well with its 360 counterpart. It is for the most part, bar some texture blurring and a contrast/gamma difference, identical.


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PS3

As expected Assassin’s Creed Brotherhood is rendered in 720p (1280x720) on both formats, with 360 getting the standard issue 2x multi-sampling anti-aliasing (MSAA) as usually seen in titles on the platform, and the PS3 once again receiving the alternative quincunx (QAA) solution.

As we’ve mentioned before in previous tech analyses, the very nature of how QAA works in smoothening jagged lines means that the entire image, including textures, gets blurred to some extend. Unlike with MSAA, QAA works on applying the smoothening algorithm to every pixel and not just specific edges.

Essentially edge-based pixels are still sampled in a similar way, however QAA uses a five-point sampling pattern which inconveniently works on all areas of the image regardless of whether an edge is present or not – pixels in both low and high contrast areas are equally affected, which is the main cause of textures becoming blurred as a result.

The choice of using QAA over traditional MSAA then, is rather strange to say the least, considering the technique comes with roughly the same processing and memory cost as 2xMSAA. But the advantage it seems, is with it being able to deliver ample edge smoothing closer to that of 4xMSA, though at the expense of overall scene clarity.

The most obvious reason for its use probably stems from an artistic decision rather than a purely technical one – there’s no reason why MSAA couldn’t have been implemented, so it’s likely that the developers actually wanted to have 4xMSAA type levels of edge smoothing on both platforms, but without any easy way to do so on 360 (you would have to use tiling). The PS3, naturally, has QAA as a standard form of anti-aliasing not included in the 360’s GPU feature-set (it’s an NVIDIA thing), so represents an obvious compromise.

However, compared to some games that use the technique, the QAA in ACB has less of an initial impact in overall image quality than you might expect. Especially seeing as the PS3 build’s 720p output remains fairly sharp and continuously crisp despite additional texture blurring.



Unfortunately, most of our comparison screens for ACB are rather compressed whilst suffering from obvious lack of proper gamma adjustment on the console end, which makes showing the clean appearance of the PS3 build and the extra sharpness of the 360 game rather difficult. As a result we’ve left all the screens untouched - free from additional compression induced labelling, whilst also bringing you two much higher quality PS3 screens in which to demonstrate out findings.

With the two shots above you can clearly see just how sharp the PS3 version really is, with the use of QAA providing a decent level of jaggies reduction without compromising the clarity of polygon edges. Some texture blurring is apparent, which is perhaps the biggest bugbear I have about the technique. But as you can see its affects aren’t especially displeasing - not in every instance - and as a result ACB still looks incredibly good on the PS3.


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PS3

Despite all our images showcasing what looks like reduced quality texturing in the PS3 build ACB, you can see that the main reason for this is a combination of both the additional blur provided by the use of QAA and the drastic difference in gamma curves for both versions.

This gamma difference is half of what makes the PS3 game look less detailed on first impressions, with textures that could be misconstrued as being in a lower resolution to those not aware of how QAA imapcts on the final image. However, the actual assets used in the game are actually like-for-like, and you can see this when both versions closely scrutinised.

Instead, it is the initially higher contrast and washed out nature of the PS3 game, in combination with the QAA which helps in hiding texture details, and making the filtering come across as looking worse, which in fact, is actually identical (same levels of AF present on both). Calibrating both the brightness through the game’s own menu, and gamma on the HDTV itself practically solves the problem, with the PS3 version looking clean and sharp with more visible detail being present after this is done.


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PS3


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PS3

You can clearly see this above: the in-game brightness setting has been adjusted in order to provide a more uniform look across both consoles. HDTV settings haven’t been touched in these two phone captures, instead showing that a similar level of brightness can be obtain by simply changing an option in the game’s menu.

For the most part, like with Need For Speed: Hot Pursuit and indeed past Assassin’s Creed titles, both versions of Brotherhood look pretty much alike in the vast majority of areas, with any differences coming across more as mere quirks and rendering oddities than anything else. Other than the use of QAA and varying gamma curves, only performance really separates them in any meaningful way. And even in this regard, ACB has seen some noticeable improvements on the PS3 side.


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PS3

In terms of performance past Assassin’s Creed titles have always been behind on the PS3, with more instances of slowdown and much greater amounts of screen tearing. Although in Brotherhood the gap has indeed been closed significantly, with less in the way of either taking place. Naturally, it is the 360 build which still commands an advantage, but both at times, feel and look very similar in this regard.

When looking at both 360 and PS3 versions of most games, it is clear that developers usually try to balance out the use of v-sync with trying to maintain a smooth framerate. Normally, PS3 owners are privy to a near solidly v-synced experience at the expense of a large increase in slowdown. Whilst on the 360, developers usually choose the opposite: ditching v-sync in order to allow for a smoother experience, but with noticeable amounts of screen tearing.

For ACB, like with past AC titles, Ubisoft Montreal have favoured the latter, in which case it is apparent that neither version employs v-sync but both can run relatively smoothly on many occasions. ACB targets a 30fps update, and the framerate is capped at that level – it never goes higher than this, but it does drop below.

However, both versions actually maintain a reasonably solid 30fps most of the time when load isn't being pushed – noticeable drops only really occur in situations where long draw distances are visible, or in areas in the city where crowds converse together. In these sections the 360 version does run smoother, featuring less prolonged dips in framerate (sometimes only by a few seconds or so) and less screen tearing. Although, on most occasions the two games operate near identically, with both dropping frames and tearing terribly at similar points. Bar perhaps the odd point in which the PS3 version felt a little smoother for a brief moment in time.

One thing that is apparent, is that the game on both platforms can suffer from regular, and continuous bouts of screen tearing even when the framerate appears to be mostly solid during the experience. In that respect, it is all too obvious that this concern from the first two AC titles hasn’t been fixed at all. The PS3 version tears more often than the 360 one, and both tear regularly in heavy load situations. Though perhaps this is something that we simply have to accept in order to gain better performance via a smoother overall framerate.

In the end ACB does display an improvement in this area on the PS3, although not quite to the extent we expected given Ubisoft publically released statement. Tearing is still an issue – more torn frames on the PS3 – and the framerate at times still struggles in a scenes with high detail and many characters on screen – on both formats no less. In which case it is obvious that despite some upgrades and optimisations, the PS3 version is still a little behind in terms of overall performance.

Saying that, there are often times where both versions are basically close to being like-for-like, and the differences during gameplay can be so subtle that they can regularly go unnoticed (between both formats). Screen tearing aside, both versions are reasonable performers, with the engine obviously struggling in situations where the overall load exceeds the capacity for it to be resolved.


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PS3

Moving on, and we can see that the engine powering ACB on both platforms has seen a few steady improvements in the lighting and shadowing departments, along with other additional effects – the water for example, in some places, now looks to be made up of more than just a few texture changes.

Dynamic lighting and shadowing has been expanded upon, and the game features noticeable cloud coverage providing moving shadows which seem to affect the lighting and shadowing on the ground. All of this is done in real time, and actually accounts for some of the shadowing differences you can see in some of the screens.


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The most obvious improvement comes with the inclusion of screen-space ambient occlusion (SSAO), which adds an extra level of depth to the scene. Use of SSAO clearly expands the shadowing properties used throughout most of the game, and can be found noticeably on characters, and some parts of the environment. Along with the use of both dynamic and static shadowing, the use of SSAO helps to bring a more defining, realistic quality to the entire scene, with ample balance between areas of the environment with and without the effect.

Also in terms of shadowing, one thing we did notice was that certain shadows feature a slightly dithered look to them, much like what we were seeing in Mafia II. The effect stands out a little more on the 360, along with the shadowmaps themselves, which look sharper as a result of no QAA blurring. However, it also appears that the PS3’s use of QAA actually provides better blending with regards to the dithering effect - it becomes less obvious as a result.


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PS3

In motion it is also possible to see some LOD issues with regards to the game’s use of shadowmaps - whereby shadowmaps feature a transitional change from lower to higher quality as you get closer to them - along with LOD issues on both platforms in general. Parts of the environment (textures, geometry, and shadows) in both the far distance and from a few feet away, tend to pop up noticeably on occasion as the engine struggles to load them in time. Though given the large draw distances it has to handle, this is understandable.

There are a few other differences to be found, but nothing major, or even anything that would really account for a clear rendering choice difference. Some shadowing and lighting oddities occasionally pop up – such as missing baked lighting on the PS3, or shadows appearing and popping in and out where they shouldn’t be. But this stuff isn’t noticeable whilst simply playing the game.


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PS3

In the end Assassin’s Creed Brotherhood is pretty solid on both platforms with the 360 version maintaining that technical edge in certain areas. On the other hand, with the exception of more screen tearing and the inclusion of the texture blurring QAA, the PS3 build is almost a good, having the same baseline assets and tech powering the game.

Even the use of QAA is no real blemish on the experience – calibrating both the game’s brightness level and the gamma on the HDTV makes overall image sharpness fairly close to that of the 360 game in this regard. The extra edge smoothing that quincunx provides can also create a more organic look to the overall visual make up of the game as a whole, with only some scenes looking noticeably worse off than others in terms of texture blur. In any case the PS3 version can be almost equally attractive if set up properly, even if the 360 game's additional sharpness is preferable.

Pretty much every aspect of the game in other areas is a like-for-like match, with only the odd rendering bug to separate them, and of course the 360 version’s lead in overall performance. But even that isn’t quite as commanding as with previous instalments – despite the PS3 build suffering from more noticeable bouts of screen tearing, the general framerate is pretty much in the same ballpark for both versions, with the 360 only fairing a little better in most cases from what we’ve played.

As to whether Ubisoft have delivered on their promise to provide a thoroughly more optimised, de-bugged PS3 experience. I think that as a whole they have. While perhaps not eradicating all of the problems found in previous titles, the overall result is far, far closer than before, with the 360 code no longer having a significant advantage. In short, there could be more work done to improve performance, but otherwise what we have here is a clear step forward in the right direction - a solid result in delivering a decent multi-platform outcome.

Ultimately, ACB can be comfortably recommended across both formats with your purchasing decision more likely coming down to which controller you prefer to use, or which format your friends play online with. The added inclusion of exclusive DLC for PS3 owners is yet another thing to consider, if a choice is indeed available to you. Either way, I’m sure most users will be happy whichever version they opt to go for.

As always, many thanks go out to AlStrong for the pixel counting, and to Cynamite.de for most of the screens. The full gallery can be found here.

Tech Analysis: Red Dead Redemption (360 vs PS3)

There’s no doubt that Rockstar are onto another success story with Red Dead Redemption. Piece together the same kind of open worldliness as in Grand Theft Auto IV, along with some traditionally styled old west action, and you have another finely crafted and life-consuming experience. If there were ever a game to make your Clint Eastwood fantasies come true, then RDR would be it.

The underlying engine behind the game is based on the same impressive tech that powered 2008’s GTA IV, expanded upon, tweaked and refined, perhaps pushing the most it can get out of the current consoles. Well, without a complete rewrite that is. And like with the GTA IV conversion, there are many similarities between the two games. Everything from the rendering resolution and the use of anti-aliasing can be plucked right out of Rockstar’s last multiplatform title, so it’s no surprise that some of what you’ll be hearing today is at least vaguely familiar.

Starting off, as always with the rendering resolution. RDR is presented in 720p (1280x720) on the Xbox 360 using 2xMSAA (multi-sampling anti-aliasing), whilst on PS3 is rendered in a slightly lesser 1152x640 and using the alternative QAA (quincunx anti-aliasing).

Straight away you can see that Red Dead is exactly the same as GTAIV in this regard, with the 360 benefiting from decent edge smoothing, and the PS3 having to make do with the blurrier quincunx solution. This choice appears a little odd, as both 2xMSAA and the standard QAA take up roughly the same amount of memory and processing requirements. So why use the poorer QAA option in the first place?



Well, the most obvious explanation is that the QAA in theory delivers more edge smoothing for the same memory cost as the conventional MSAA, so thus there should be less in the way of jagged edges. However the consequence is that QAA not only smoothens polygon edges, but also blurs general pixel details in the entire scene. So textures along with geometry become blurred, creating a softer overall image. Bizarrely the use of this QAA seems to be selective, with some edges getting clear levels of jaggies reduction, and others without.

Unlike in GTAIV, in which the blur effect actually added an ambience and a layer of atmosphere to the proceedings, in Red Dead it does nothing of the sort. The gritty environments of GTA made the QAA look fit in well with the game world, and the 360’s dithered textures made the loss of sharpness a worthy compromise on PS3. However RDR on 360 doesn’t really suffer from any dithering textures. Or rather, that the effect has been greatly reduced, and the bright and dusty open world nature of the game benefits from a sharper image, meaning that the blur effect simply heightens the differences between the two versions.

The 360 build however, isn’t free from criticism either. The high contrasting edges between the buildings with the bright blue sky often leads to noticeable shimmering, sometimes as bad as seen in the PS3 build. Most of the time these jaggies are in fact smoother than the ones seen on its PS3 counterpart but shimmer in the same way.

Essentially MSAA works by taking samples from two adjacent pixels, and then combines those samples with the final image to form an anti-aliased one. With edges in high contrast areas, there isn’t enough information to create decent samples to act as in betweens where the two pixels meet, thus the image receives either no AA altogether, or a significantly reduced amount.



In terms of texture detail and filtering, both versions are identical. Texture resolution seems to be the same on either platform with the lower 640p resolution of the PS3 game resulting in some additional blurring of the visible detail. This is caused by both the upscaled nature of the framebuffer, and the use of QAA, in which we’ve already discussed the technique’s unwanted side effects.

Anisotropic filtering is evident in the screenshots below, as is the blurred nature of the PS3 version’s textures, and general screen composition. The levels of AF don’t appear to be much higher than what is usually available with the older trilinear method of filtering. So we are looking at perhaps 4x AF for Red Read on both platforms.



One area of the game that has been noticeably paired back on the PS3, is the heavy use of alpha-based foliage. This seems to be the main reason for the lower resolution of the PS3 version and it’s use of a more aggressive LOD (level of detail) system in certain scenarios.

As we’ve discussed before at IQGamer, the use of alpha heavy transparency effects for objects like hair and foliage use up a huge amount of bandwidth, a commodity which is particularly limited in home consoles, but especially on the PS3 with its lack of high speed EDRAM. It’s this bandwidth advantage which allows the 360 to not only render more foliage on screen, but also render it at a higher resolution as well.

These two shots show exactly how much of the foliage has been cut back on the PS3 game. Notice how it is mostly only the smaller plants and grasses that have been culled, which actually has less of an impact during play than you might expect. However it’s also pretty clear that the environments in the 360 version look visibly more dense as a result of having loads more minor pieces of foliage.

Some major parts of the foliage have also been cut on PS3 too. When this happens, the Sony version of RDR looks much blander as a result, taking away some of that ‘living world’ look that the game at times possesses.



Whilst both versions use A2C (alpha-to-coverage) for the surrounding foliage - a memory saving technique for rendering half resolution transparencies in an interlaced type manner - the 360 version clearly benefits from better alpha blending through the use of A2C in conjunction with 2xMSAA.

On the other hand, the PS3’s use of QAA and low-resolution foliage makes for a poorer blend overall, and some unsightly shimmering artifacts which don’t look too great with the blurred nature of the framebuffer.

As regular readers of this blog might know, A2C also creates a screen door effect on all transparencies and textures that use it. MSAA is used to blend away this unwanted effect, and the more AA used, and the higher the resolution of the A2C textures, the better the overall result will be. For RDR the PS3 game and its use of low-res foliage and QAA simply makes the screen door effect stand out far more than it does on the 360. By contrast, it’s barely noticeable in motion in the 360 build.



Along with a reduced foliage count, the PS3 game appears to feature a more aggressive LOD system as well. It’s not so much the issue of objects being cut back on the PS3 build, but also of objects popping into view later than in the 360 one. Geometry changes, shadow pop, and object pop in are all more noticeable on the PS3. Although these do occur on 360, but to a far lesser extent.

Below you can see the differences between the two versions. Notice how the water effects and shadowing have been cut back on the PS3, with entire shadows missing altogether. Detail in the distance has been deduced, with buildings featuring simpler levels of geometry, and with some objects being completely omitted from the scene.

The PS3 version also suffers from some other LOD issues as well. In towns and small outposts, as you approach the buildings the shadows pop in a lot later in the PS3 build compared to the 360. They appear more erratically on the PS3, whereas on 360 they appear smoothly on screen from further into the distance, and in a far more succinct manner.

The reason why, on occasion, that so much detail has been reduced in the PS3 build, is due partially to the game’s lower resolution in combination with the blur inducing QAA, and what appears to be a more forceful LOD system.

Either way, the Sony game suffers far more from LOD issues and the overall more aggressive LOD system in place for RDR. Unlike in GTAIV, the whole game has been designed around sprawling vistas, and wondrous views into the far distance. So its no surprise that some large compromises had to be made for the PS3 build, especially where trying to keep a more consistant frame rate is concerned.



Red Dead Redemption aims to keep a steady 30 frames per-second framerate at all times, but both versions deal with doing this a little differently. Like with many multi-platform titles, the PS3 build is focused on eliminating screen tear at the expense of maximum smoothness, being v-synced that is, and the framerate also capped at 30fps maximum to ensure it never goes above this level.

The 360 build on the other hand is more concerned with maintaining as smoothest framerate as possible. And to that end the framerate hasn’t been capped at all, with the game running between 40 to 50fps in certain scenarios. This mainly happens when on foot, and in enclosed locations without much in the way of foliage and environment detail.

Most noticeably is the fact that the 360 game isn’t v-synced, or v-locked at all, meaning that it is prone to screen tearing in stressful situations or fast camera pans. The tearing only ever appears at the top of the screen, and stops halfway across the screen, almost like the game has caught up with the problem.

By contrast the PS3 game never tears any frames at all, remaining completely free of the problem regardless of what is happening on screen. However, it does drop framerate badly in heavy load situations, far more than the 360 game. When this happens, the screen can crawl with jagged edges and shimmering foliage in areas in which the QAA isn’t applied, and where the A2C blend fails to work successfully.

Both versions do massively drop their framerate in heavy load situations, but it’s the PS3 one that seems to be more greatly affected by such dips in performance.

So it is safe to say that performance wise the 360 version has the edge, and that the screen tearing present on that version of the game isn’t much of an issue, being barely noticeable for much of the time. By contrast, the PS3 build features a small drop in IQ over the already worse 640p resolution and use of QAA whenever the framerate drops. That said, neither version maintains the target 30fps for long, with constant dips below all throughout the game.



Moving on, we can see that in terms of lighting and shading there are differences in both versions of the game. For the most part they are both largely identical, but in certain circumstances the PS3 build actually features more light reflections and extra shadows cast in indoor areas, and the 360 build gets self-shadowing on all characters, which are absent for some on PS3.

The lighting differences don’t always seem to be technical achievements, but rather technical anomalies, in which it seems more likely that there is a rendering error on the 360 build compared to the PS3 one. Although we cannot be sure as to why this is happening without knowing the ins and outs of how Rockstar’s engine renders its shadows and lighting in detail.

In the screenshots below you can see how the PS3 version is casting a light source from outside and through the window, into the scene indoors. Whereas on 360 it is clear that the only light source affecting the characters is the one coming from the wall-mounted lamp.

The light source that is cast through the doors and windows on the PS3 game also casts shadows from the characters and onto the grown. Something that is also absent from the 360 build, which again only gets shadows from indoor lighting.

Thankfully these scenes are few and far in between as most of the game is set outside, in which there are only a few minor cloud shadow oddities in the 360 build. However it does mean that in indoor scenes the PS3 clearly demonstrates better use of lighting, whether that be due to an error or otherwise.



The 360 build however, does have the benefit of having both sharper and higher quality shadows for character and environmental objects. All characters on 360 have the benefits of using self-shadowing – shadows that are cast upon characters by themselves - which gives them an extra depth and three-dimensional look.

On PS3 characters generally look flatter than their 360 counterparts, with some lacking self-shadowing altogether, and others simply having the effect paired back over the 360 build.

It’s pretty obvious in the screenshots below how superior the shadowing can be in the 360 game. Notice how much extra in the way of depth the self-shadows can add over environment shadowing and lighting.



In the end, despite the differences we can still see that what Rockstar’s engine has achieved on both platforms is pretty impressive, with it’s ability to render miles of detailed scenery and still keep up a decent framerate outside of strenuous encounters. Red Dead Redemption may not be artistically pleasing to everyone, but is still a mean technical achievement. It is however, one which favours the strengths of Microsoft’s console, with the 360’s superior vertex processing capabilities and greater memory bandwidth.

From what we’ve uncovered today, it’s pretty clear that the 360 demonstrates superior technical prowess when it comes to handling the wide and open-world nature of Red Dead Redemption. Unlike in GTAIV, a far-reaching field of view is absolutely required in order for a game like RDR to accurately represent the time and period in which it’s set. And it’s also exactly the type of engine that is ill suited to PS3’s lack of bandwidth and vertex shader power.

It comes as no surprise then, to see that without large buildings and natural structures hiding far off areas, that Rockstar had little option but to noticeably cut back on the sheer amount of geometry present in the PS3 game. After all, you can’t start culling much in the way of unseen polygons when the game requires most of this detail to visible from far into the distance. Instead the only thing left to do is cut away at the foliage, sap away some of the resolution and try to make the best of what you’ve got left.

However most of these differences aren’t all that visible unless you’ve seen one version, and then moved on to playing the other. Someone whose only ever seen the PS3 game is more than likely not to notice most of the issues we’ve highlighted in our tech analysis, and will still enjoy the many superb experiences Red Dead has to offer. Perhaps the only thing that IS noticeable is the blurred nature of the game owning to the use of QAA. In that respect it is the game’s largest issue, and the one which takes away the most from the experience.

In conclusion, our recommendation rests with the 360 version. There’s simply no doubt that it’s use of a higher resolution, proper MSAA, better LOD detail, better shadowing system, plus more stable overall performance makes it the better of the two. This isn’t a case of GTAIV, in which the slightly blurred look adds to the visual style of the game world, but rather that every part of RDR benefits from having a generally cleaner and clearer look about it, with more detail and a smoother framerate all gelling it together.

However, that said there’s no reason for people with access to only a PS3 not to pick up Rockstar’s latest. As we’ve stated above, that unless you’ve seen the two versions running you’ll unlikely to notice most of the differences, and the game itself is the same on both platforms, being an utterly absorbing experience at times, and one of the best open world games to date.

Thanks to MazingerDUDE for the majority of our comparison screenshots, and as always, to Quaz51 for his exemplary pixel counting skills.