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We’ve had the Final Fantasy XIII demo for quite some time now, and our detailed analysis of the code (and by extension our first look at Square-Enix’s Crystal Tools engine) is now complete. First impressions? While the engine itself doesn’t particularly excel from a technical standpoint, it’s still a great-looking game, with much of the credit reserved for the development team's many artists.
First things first. Despite some rumbling from certain quarters of the internet, the game engine is most definitely running at 720p resolution, with clean visuals brought out thanks to the inclusion of 2x multisampling anti-aliasing. The inclusion of MSAA is somewhat rare on PS3, but very common indeed on Xbox 360. What is clear, however, is that Square-Enix is facing key technical challenges, with variable and sometimes disappointing performance in the demo code. Translated interviews suggest these issues have already been overcome, but in the here and now, the apparently outdated demo is all we have to work with.
Square-Enix is clearly targeting 30FPS for the game, but it is falling some way short in certain scenes and that’s generally down to the bewildering range of transparent alpha effects employed in the combat. This generally doesn’t tend to be so much of an issue for 360 (thanks to the daughter module of 10MB eDRAM connected directly to the GPU), but it can hit PS3 hard. The solution is generally to employ a lower resolution buffer for these effects (as seen in Killzone 2 and Red Faction Guerilla to name two examples), but right now, Square-Enix is adopting a zero compromise approach to the visuals in terms of visual effects and that’s what’s causing the lag. Where the company is compromising is with certain effects such as the characters’ hair. You’ll see an almost interlacing-style effect – it’s called ‘alpha to coverage’ and it’s an immense fill-rate saver, albeit at the cost of visual quality.
But any way, onto the technical analysis. We have two videos for you to digest, available in both embedded article format and streaming HD. Let’s get going.
The first video deals with a lot of what we’ve covered, along with further technical notes on how Square-Enix has achieved what they have with the demo.
A second video, with more action from the demo. Towards the tail-end of the vid, we try to put the engine under as much stress as possible to see much the frame rate can be impacted. You’ll also note that some scenes with multiple characters on-screen can also make a real dent in performance. What is interesting about the characters themselves is that while their heads are very highly detailed, the bodies have far fewer polygons in comparison. What is also curious is just how much Square-Enix relies on 2D artwork for the backgrounds, with token 3D objects overlaid to give a greater idea of depth. Again, the fact that it works as well as it does is entirely down to the quality of the art.
This final video is analysis-free and simply collates a range of the game’s pre-rendered video scenes. Final Fantasy XIII actually employs different types of cut-scene. There are the showpiece CGI scenes, which are rendered at full 1080p. Next up, there are what you might call engine replacement scenes. There’s nothing here that the engine itself couldn’t render, but it appears that Square-Enix has decided instead to off-load more complex scenes to pre-rendered video, allowing them to break out more crazy effects, higher detailed models and even 4x multisampling AA.