Assassin’s Creed Shadows has finally been revealed. After a short CG trailer debuted a few weeks ago, Ubisoft has finally unveiled a lengthy gameplay demo for the upcoming title. As the first current-gen only effort in the long running series, it seems poised to take advantage of current-gen technologies, like ray tracing. At the same time, early impressions suggest a game that might provide a more iterative uplift over previous titles. So what kinds of technology gains are we finding under-the-hood? Where does AC Shadows improve over prior series entries – and where is there still room for further development?
The most headline-grabbing – and possibly most important – AC Shadows tech innovation is the addition of ray traced global illumination. Ubisoft’s Anvil game engine now supports RTGI, according to key developers and the tech press. Here, I think the visual results are a little ambiguous. On the one hand, the lighting in broad strokes looks appealing and there is proper occlusion around larger elements of static geometry. There’s a similar effect in wooded areas, where dense pockets of underbrush appear to occlude light in a fairly realistic manner.
That said, the effect isn’t quite so pronounced on smaller environmental elements, while shadows often look flat, without much of a gradient. The visual results are still perfectly fine, but there’s less of an impression of per-pixel detail in these areas. Later in the demo, there’s some obvious light leak within an interior space and there are a couple instances where lighting detail appears to pop-in as the camera moves forward. These factors, taken together, may suggest a probe-based, and not per-pixel, RTGI technique. Skull and Bones – another Anvil game engine title – also supported probe based RTGI, so its inclusion here would make a lot of sense. We’ve seen probe-based RTGI in games like Star Wars Jedi: Survivor, and it can produce very effective results depending on implementation.
A giveaway here is how lighting information changes as the player moves through the environment. A probe based system can suffer from more obvious pop-in as the player nears, as chunks of detail from the probes pop into view. A per pixel system should more gently change its lighting characteristics as the player draws close, becoming more granular. Of course, presented with this limited and relatively low-quality YouTube feed, it’s not possible to get the kind of clarity that would make this evaluation easier. I think regardless of the technique used, Assassin’s Creed Shadows has a good-looking lighting presentation, and the switch from a pre-calculated to real-time GI system likely helps to minimise install size. The game also has a variable time of day and multiple in-game seasons, creating additional complications for a ‘baked’ GI system.