Face-Off: Batman: Arkham City

Following up the excellent Arkham Asylum was always going to be an awesome challenge for UK developer Rocksteady, but given two years of development time and plenty of inspired design choices, Batman: Arkham City is an outstanding experience all round. In terms of gameplay, the biggest change comes with the introduction of Arkham City as the game's 'hub', where main missions and side-quests are accessed.

The new, open playground of Arkham City also brings about some major changes to the visual look of the game. Unreal Engine 3 has seen its fair share of enhancements over the years, freeing it from the shackles of the smaller, more claustrophobic level layouts originally favoured by the tech and into much bigger spaces. Here we have an expansive landscape, complete with plenty of areas to explore along with a large amount of buildings which contain the bulk of the game's story missions. The mixture of the more constrained environments seen in the last game and new open-area segments works wonderfully, giving the player plenty to do whilst also showcasing the improvements made to the underlying game engine.

A few tweaks and optimisations to UE3 has also allowed for an even closer multi-platform conversion than we saw in Arkham Asylum. As our Batman: Arkham City 720p comparison gallery and head-to-head video demonstrate, many of the differences found in Batman's last outing - ranging from lower resolution textures and pared back effects on the PS3 - have mostly been eliminated. The changes made to UE3 also allow for an upgrade in environmental detail and additional lighting effects.

Starting off, the first thing that visibly sticks out is the quality of the artwork on both formats: it's largely identical with very few differences between them. In comparison there were a fair few examples of lower resolution textures and paired back normal maps on the PS3 version of Arkham Asylum, which have now been taken care of. The alpha buffers are also rendered out in the same way on both formats - there's no drop in resolution on the PS3 - with smoke, fire and other effects looking identical.

With regards to texture detail, most of the peculiarities apparent in our comparison gallery are likely down to the game's LOD system of streaming in higher quality artwork: things appear pretty much interchangeable between both consoles, though there are times when the PS3 appears to be slightly ahead - bar the odd occasion whereby high resolution textures fail to load, or where high resolution assets are briefly swapped out and the swapped back in again.

Given the increase in load when dealing with detailed open world areas, it appears that Rocksteady has carefully chosen to remove certain elements of the game's visual make-up in order to help maintain a steady 30 frames per second update, while also upgrading the visuals significantly in other areas. We presume that the idea here is that those extra GPU cycles can be used for more important duties elsewhere: the lighting model is visibly improved over the previous release and we don't see quite the performance hit you might expect from the graphical boost the new game offers.

In terms of the specifics, the 2x MSAA present in the 360 version of Arkham Asylum has been excised, with both versions of Arkham City recieving no edge smoothing at all while screen-space ambient occlusion (SSAO) has been removed on the Microsoft platform. Again, neither version utilises the effect at all.

The end result doesn't have all that much of an impact: we're still looking at a native 720p framebuffer on both formats, and the application of MSAA in Arkham Asylum added only mild benefits to overall image quality. As with most UE3-based titles that use anti-aliasing, sampling is carried out before various elements of the scenes are rendered - usually lighting and post process effects - and as such the overall impression we got was that the AA was selective: visible on some edges, so its overall impact wasn't especially noticeable and removing it almost certainly frees up some GPU cycles.

For the same reason, the lack of edge smoothing in Arkham City isn't really much of an issue on either platform. It's only in the more open areas of the game that we see some noticeable jaggies, with elements such as fences, railings and other metallic materials causing shimmering, pixel-crawling issues. Curiously, edge shimmering on some sub-pixel elements appears to be less evident on the PS3 in places. The cause of this seems to stem from the brighter gamma set-up on the platform along with use of a less intensive bloom component, than from any additional edge smoothing.

Similarly, the omission of SSAO isn't especially an issue here, either. The effect was subtle and very difficult to pick up in Arkham Asylum within the game's overall aesthetic. Its omission here isn't really a problem considering the amount of depth on offer with the existing shadowing model.