Assassin’s Creed Shadows’ New Tech Ramps Up the Environmental Immersion [CNET]

Rain and weather affecting stealth, swords slashing through objects, swathes of generated trees — and few poorly-rendered pop-ups.

Assassin’s Creed Shadows, the next game in the beloved franchise, will stand out from its predecessors for many reasons. But the two things that will distinguish it the most are that, at long last, the new game will be based in Japan — and that it’s the first in the series designed after the PS4 and Xbox One era, so they’re going all out on graphics. Ubisoft says that the tech advancements to its Anvil game engine give AC Shadows the most immersive environments in the series to date.

That doesn’t just mean gorgeous locations and buildings accurate to the late 16th-century Sengoku period of Japan, where and when the game is set. During presentations and interviews I sat in on during and after Gamescom in Cologne, Germany, Ubisoft’s tech directors explained just how much the new tricks in the Anvil engine powering the game make players feel like they’re walking around in a richly realized world layered with dynamic weather and procedurally-generated conditions, from the clouds in the sky to the dust under your character’s feet. 

It even applies to whatever stands in front of the player’s blade — if you slash through bamboo trees, they’ll fall in the path your katana took.

“When we started looking into what we wanted to do with AC Shadows, we often said that we wanted to move from a beautiful postcard to a beautiful movie in the way that we produce super nice images and things like that, said AC Shadows technology director Pierre Fortin. But in this game, he continued, “what we want to show is something that’s a bit more in action and more dynamism on screen.” 

Small details combine into a storm of immersion

Ubisoft believes this will drastically improve immersion, and in the behind-closed-doors tech presentation at Gamescom I saw, I was wowed by the efforts toward replicating the way trees, light, weather and rain look in real life. It got to the point where the voice of the presenter, AC Shadows art director Thierry Dansereau, was drowned out by wind whistling through trees and water splashing through gutters, with visuals showing off light dappling through leaves in a bamboo forest and snow flurries dusting snowflakes around the characters’ feet. 

These are the small details — “what in your day to day life that surrounds us but we don’t pay attention to,” as Dansereau describes it — that in AC Shadows will passively usher players into being more immersed than other games before.

“When you’re able to translate that into a video game experience, now [players] brains perceive it as reality in a way,” Dansereau said. 

This dynamic environment isn’t just for looks — it affects how you’ll play, the directors explained. Weather changes in the open world as time progresses, so maybe you’ll want to wait until a night rainstorm to sneak into a castle town, where the blustery noise and curtains of rainfall will limit how perceptively guards can detect players. That cuts both ways: fog on a humid summer day or a snowstorm might help conceal you, but winter weather might freeze a lake, stopping you from stealthily swimming up to a building. These are some of the many procedurally generated variables that make the world unpredictable — and thus more immersive, Dansereau said.

As AC Shadows won’t launch with last-gen compatibility for the PS4 and Xbox One, the team was able to push what the Anvil engine can deliver in the PS5, Xbox Series X and PC. Shadows has ray tracing to enable light to glimmer off the surface of koi ponds and rivers. But the team also did plenty of research and pushed their lighting technology to add layers of weather particles that gets just the right flavor of light in Japan.

“There’s a lot of light scattering through mist and fog, which makes that Japanese light that everyone refers to, like the people who travel to Japan,” Dansereau said.

Tech advancements in the Anvil engine mean many more objects are rendered far beyond the player’s sightlines, minimizing the number of poorly-rendered pre-made objects popping in the background. Like other under-the-hood improvements, this one’s better if players don’t pick up on it, Dansereau says: “So maybe some people will never notice most of the features that we’re putting in because it blends so seamlessly. So if that’s the case, it’s perfect.”

As previously mentioned, the game has dynamic environmental destruction — while you’re playing as the shinobi Naoe or samurai Yasuke, your sword slashes will carve up bamboo trees, bushes, paper doors and so on in the patterns that your blade makes. This, too, required tech advancements to render objects cut in many ways and orientations — something specifically done to better enliven the setting of feudal Japan.

“We wanted to fulfill that fantasy of having a sword that’s super sharp,” Fortin said. “We did push the tech in that direction to present a Japan that’s more credible.” 

How much AI is in AC Shadows?

Back in 2020, Fortin explained in the official blog for Epic’s Unreal engine that the ballooning amount of data for modern games, including Assassin’s Creed Origins and Odyssey, was challenging developers. At the time, he looked to advances in machine learning and artificial intelligence to synthesize that vast amount of data and help do some of the tedious animation work to free up animators for areas that need human craft and input.

And despite the skyrocketing use of AI in tech and its expansion into gaming, Fortin says not much was used in the development of AC Shadows. As he predicted, one advancement for AC Shadows was using lots of procedural generation to do things like filling the world with everything from big trees and buildings to pebbles at characters’ feet generated on the GPU while players are playing — and change it based on the in-game season. In the past, this wasn’t possible because one set of data was (in simplified terms) pre-recorded into the game’s data.

“Now with that deck of GPU scattering that we’re able to, for example, [propagate] the world dynamically with different types of assets given the fact that you’re either playing in the winter, summer or spring,” Fortin said. 

Back when he was quoted for the 2020 piece, he thought the industry was going to see an increase in AI-assisted human procedural generation, as Fortin described it, but they didn’t end up using any of what’s known as generative AI tech in AC Shadows.

Bigger games, better tricks for ray tracing and more

There are other ways that the Anvil engine’s advancements will impact what players see in AC Shadows. Fortin was right about the increase in game data complicates game development, but it turns out that some new technologies help that out. Ray tracing, for instance, refers to rendering light on reflective surfaces, and the team built a global illumination system that ended up removing steps in the game’s production pipeline. 

The AC Shadows team was able to shift the ray tracing global illumination system that was heavy on processing power while making builds to processing while the game runs, which had the extra boon of freeing up the developers to enable things around the player to change on the fly while the game is running. 

“So, for example, introducing a system like ray traced global illumination allows us to have that capacity in AC Shadows to destroy objects and to see the light being changed around those objects dynamically,” Fortin said. 

In summary: players get nicer lighting and developers can keep up with the advanced complexity of the games they make.

From weather flowing around players to objects destroyed by their blades, AC Shadows has a lot of improvements under the hood that seemingly make it the most advanced Assassin’s Creed game ever made. 

We’ve heard all these claims for dynamic weather and conditions from games in the past, so it’s nice to see presentations demonstrating how this tech works in real-time, along with details from the directors who made them happen. We’ll see if it all works as promised when Assassin’s Creed Shadows launches on November 15th, 2024.