Square has repeatedly said that the video was not made up of pre-rendered, but it was video in real time.
At the end of the movie title is revealed: Agni's Philosophy: Final Fantasy Real Time Tech Demo. We do not know if it's a preview on the future installment of the series or if it features material created just for demonstration, what is certain is that Square Enix is keen to point out that this is a demo material in real time.
As further evidence, in fact, during the presentation of Hashimoto spoke changing scenes of the trailer and changing hair colors and characteristics of the protagonists or the lighting. We leave so impressive demo: forbidden to watch it at lower resolution to 1080p!