Monday 22 November 2010

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.


360


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.


360


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.


360


PS3


360


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.


360


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.


360


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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PS3

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.


360


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.

6 comments:

  1. I'm an outsider who came across your blog by chance. I was actually looking for some recognition in regards to bad framerate in the PS3 version.

    It has been driving me insane because not everyone seems to be getting bad framerates. I've asked Ubisoft for their opinion but they just ignored me after my reply. I've tried switching TV's, changing settings but ACB runs like shit in largely populated areas. Drops from 30 fps to about 12 and makes it a horrible experience.

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  2. One thing that I dont like about the ps3 version is the difference of color... could you please tell me how to make it look like the xbox version, in terms of contrast/gamma adjusting?
    thanks.

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  3. I'm also looking for some recognition with the frame rate issue on PS3, it's driving me nuts.
    I'm returning this game for the 360 version.
    I was told the graphic looked better on PS3, and they do, but if I'm being cased by a large amount of guards, in a crowded area the frame rate is unbearable. Being an Assassin's Creed, this happens a lot.

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  4. Have you noticed there is a strange lighting in the third picture? Some people say gradient graphical filter that is there intentionally but it somehow doesn't fit to interior lighing a I personally find it quite annoying. Is there any way how to disable it? (on Xbox 360)

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  5. thank you very much for the info. i have played the last two AC on Xbox 360, but decided to play the brotherhood on PS3, and i have to say i made a big mistake, but the Graphic Lagging and Poor fram rate is on my nerve and i do not enjoy playing this game whatsoever.
    im glad i read this article because as it seems many people have come across this issue.

    regards

    sam

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  6. Hello people,
    I thought I was the only person that had this problem, I have the 360 version, Multilpayer runs perfect, but singleplayer, damn, it realy makes me get sad, I wish it were like ACII, The best Framerate from the 3 games.

    ReplyDelete