Digital Foundry always has the craziest tech-heavy breakdowns of in-game graphics and console hardware. Take a gander at some of the technobabble in their latest article that covers the differences between the PS4 Unreal Engine 4 tech demo and the one created for the PC:
While the lack of real-time GI is a bit of a blow, we get the impression that this really heavy tech proved too much for the new console hardware (and bearing in mind the power of the PS4, an array of lower/mid-range PC graphics cards too) because it’s been replaced with an enhanced solution of the “baked”, pre-computed lighting system used in Unreal Engine 3: Lightmass. This works in combination with a form of real-time global illumination on objects – not exactly a new approach, as the same basic principles were in place on Halo 3.
That’s a serious paragraph that means a lot to people that care about these kinds of things. All I know is that my PS4 version of Gears of War 4 is going to look great!