Tech Analysis: Final Fantasy XIII
How the game changed from demo to PS3 retail, and what we can infer for Xbox 360.
Exploration elements (specifically the series towns) are cut down to a minimum: there is talk in the Final Fantasy XIII Scenario Ultimania "mook" (a kind of Japanese reference bible talking about the game's production) that creating convincing HD towns was simply too much work, so the developmental focus was shifted elsewhere.
So while there are three cities within FFXIII, gameplay within them doesn't take the form Final Fantasy veterans will recognise: there's no ability to talk with NPCs, for example. Only Chapter 11 offers the kind of exploration and side-quest elements you would expect from a top-tier JPRG.
However, while it will not be to everyone's taste, it seems that the core of Final Fantasy XIII is to present an incredible journey, with stylishly realised, beautiful characters and a vast range of stunning environments put together with a combination of cool engine technology but, just as importantly, impeccable taste. Whether that is going to be enough for the audience remains to be seen: Final Fantasy and JPRG fans might not be too happy with the direction Square has taken the series.
However, the more linear approach to the gameplay does mean that Final Fantasy XIII will undoubtedly be much easier to convert onto the Xbox 360. While a more freeform approach could have seen you jockeying discs about as you move from one area to another, Square Enix has confirmed that the three-DVD Xbox 360 version will only see two disc-changes throughout the duration of the entire game.
However, porting the game across to the 360 must have been a daunting proposition. Taking a look at the structure of the Blu-ray disc, we see an absolutely colossal 32.6GB of what looks to be pre-rendered movies, while the actual gameplay content itself is a more reasonable 6.8GB. Co-incidentally, 6.8GB is also the maximum usable space developers have on the dual-layer DVD (yes, Xbox 360 games theoretically have less storage available than PS2 and Wii titles).
In one of the first Digital Foundry articles published on Eurogamer, we analysed the original demo code and theorised that a good portion of the movie content could be repurposed into the game engine without too much trouble, saving valuable disc space at the cost of some loading time. However, it may simply be the case that the development team will opt to re-encode the existing videos. Will the majority of the audience notice lower-bandwidth video? Do the assets really need to be 1080p?
In putting together the Face-Offs, we have two examples of developers who have used the storage potential of Blu-ray to massively increase the data budget allocated to their pre-rendered CG sequences. In both cases, the games have increased in size to over 20GB, while the Xbox 360 versions still fit easily into that 6.8GB of DVD space. Darksiders, covered in Face-Off Round 24 just last week, is one such example. Here, we've attempted a quality comparison by slowing the video down significantly, then using insane-level h264 encoding to preserve as much quality as possible.
Going back to the latter end of 2009, Tekken 6 was another game that featured enhanced movie content, utilising 20GB of Blu-ray space for higher-quality video in some places, and 60FPS cut-scenes in others.
Of course, while both of these games demonstrate that you can significantly reduce bandwidth without compromising picture quality that much, the jury is still out on Final Fantasy XIII simply because of the sheer amount of video the game contains.
Assuming the game content in terms of graphics, audio and code stays around the 6.8GB ballpark, the challenge Square faced boiled down to condensing 32.6GB of data down to 13.6GB - whichever way you slice it, that's a big ask. Video compression aside, FFXIII's audio is completely uncompressed on PS3. Adopting the 360's in-built Dolby Digital 5.1 compression will help matters considerably, at the expense of top-end audiophile-quality surround of course.
Square itself remains confident overall in the quality of the conversion. Speaking to the Dutch Official PlayStation Magazine (and translated by FinalFantasy-XIII.net), FFXIII producer Yoshinori Kitase said, "We have made it our top priority to deliver the same quality on both consoles. It was self-evident that it brought some difficulties with it. Both consoles require a different approach. Especially on the graphics section. We had to build a different engine for both versions. We needed a year of tinkering on each engine in order to get the same level of graphics."
Whoa. Up until now we had always believed that the Crystal Tools codebase that powers FFXIII had been designed as a multi-platform engine. Assuming the translation is sound, we're now talking about two entirely separate pieces of code, but presumably handling the same core assets. Final Fantasy XIII is due for release on both PS3 and Xbox 360 in Europe and the US next month; the inevitable Digital Foundry/Eurogamer Face-Off will certainly be interesting...
Many thanks to Alex Goh and MazingerDUDE for their assistance in creating this feature.