Final Fantasy 15 is a very different beast to the one we've caught glimpses of over the past ten years.
Final Fantasy 15 has changed a lot in the ten years since its 2006 announce. You could almost say it's an entirely new game - new title, new engine, new platform, new development team - if not for the fact that the "game" we first saw a decade ago was just a collection of CG trailers for a project not yet in full production.
In the video above, Digital Foundry revisits those old trailers and some later gameplay demos from when work had actually started, noting that almost everything you see in Final Fantasy Versus 13 materials was thrown out for Final Fantasy 15. The major characters and some environments persist, and it looks like Noctis's teleport ability was always on the cards, but almost everything else just vanished.
This holds true even after the project was re-revealed as Final Fantasy 15: there are loads of Final Fantasy 15 videos and screenshots that show content and scenarios completely absent from the released game.
This is really interesting, but it's the end of the video where the report is able to get technical. The content found in the 2015 Episode Duscae demo is mostly present in the finished version of Final Fantasy 15, but even there, there are significant changes to the visuals and performance.
The report highlights the differences between Final Fantasy 15 and the Episode Duscae demo's lighting systems, and how the artistic haze seen in the demo was removed for the full version.
There's far less noticeable pop-in in the finished version of Final Fantasy 15, although it is still present, and much more vegetation to give the environments a lusher feel. On the other hand, the demo had better texture filtering. There's also a difference in the water effects; I like the demo version better, personally, but I guess the finished one is more realistic.
The big change is to performance. Episode Duscae had major issues with hitches, skips, slow down and frame pacing, and that's despite being 900p with poor anti aliasing. Although the finished version of Final Fantasy 15 definitely has frame pace issues on PS4, in general the PS4 build "dramatically" improves on the demo - and the Xbox One's improvement is even more marked.
One day I'd like to find out just what Testuya Nomura had planned for Final Fantasy Versus 13, and indeed why Hajime Tabata made such dramatic changes to the content shown in earlier Final Fantasy 15 materials.