A Plague Tale: Innocence - a fascinating game powered by stunning tech
A bespoke engine from a smaller developer delivers triple-A level visuals.
Asobo Studio deserves kudos for the scale of the achievement delivered in the recently released A Plague Tale: Innocence. Where many smaller studios tap into established engines like Unreal Engine 4 or Unity for their technological needs, this outfit did things the old-fashioned way, developing its own proprietary engine technology. The end result is an absolutely beautiful game and one that scales remarkably well as we climb the console ladder and beyond to the heights of PC's most powerful graphics hardware.
I think what makes A Plague Tale really work from a visual perspective is more than just the core engine technology - though its accomplishments are significant. Combining a linear, story-driven experience with a striking art style and design running on this tech sees all components deliver something greater than the sum of their parts.
A Plague Tale: Innocence is a wonderful-looking game from its environments, to its characters, and its effects work. Just the first scene is an absolute treat, revealing a rich post-process pipeline that's reminiscent of Unreal Engine 4 at its most resplendent. There's an embarrassment of riches here, with a beautifully soft volumetric lighting solution, which looks good on all platforms but absolutely shines on PC at its highest settings. Volumetrics don't just come from the sun: lighting piercing fog, suggesting that colour and shadow are drawn from smaller point lights, such as lanterns or torches. It's also impressive to see volumetrics beam through stained glass windows, with the varying colours of the glass illuminating light shards and - impressively - the ground too. It's just one example of an attention to detail that is much appreciated and sometimes overlooked.
Also impressive is the sheer density of the scenes. No doubt the linear nature of the game makes authoring and rendering these environments easier than some of the open world epics we see from the triple-A studios but even the simplest levels are thick with forest, brush, undergrowth, leaves and twigs. A Plague Tale takes advantage of Quixel Megascans - a library of photogrammetrically-sourced textures and materials. Using this drastically lowers the burden of asset creation, with Asobos able to tap into a pre-existing library of textures and material surfaces, allowing the staff to focus on modelling, placement and lighting instead. The end result is a high level of quality and consistency, with an aesthetic reminiscent of the Dark Souls games or The Vanishing of Ethan Carter.
The characters themselves also possess a high level of quality that stands up against games created with a much higher budget. It starts in the soft glow of the game's direct lighting with an approximation of sub-surface scattering on character skin along with an effective hair shader. It seems to use alpha-to-coverage cards that clean up over time using temporal anti-aliasing. Hair also shows a particularly nice, authentic-looking multi-coloured sheen, with a soft look around its edges. While the game offers very high resolution shadow maps (on PC at least), even these would still suffer under the closer inspection on characters. Asobos instead utilises screen-space self-shadowing that seems to apply from any light source. This keep shadows on faces tight and detailed in close-ups, but do have typical screen-space problems where they disappear when obscured, or when the shadow-casting object falls out of view. Eyes are the only aspect that fall noticeably short, looking rather glassy,
Even with that minor blemish though, the characters are distinct, convincingly animated, and have wonderful voice-acting - keeping the filmic appearance intact - emphasised by a healthy depth of field found in all cutscenes. There is the sense that the post-process pipeline can go too far though, especially in terms of chromatic aberration found across the entire image, not just the edges. It's akin to Bloodborne in terms of its intrusiveness and a toggle would have been welcome. PC owners can disable it via an .ini tweak and to my eyes the image is improved. There's a zoomer screenshot comparison image on this page so you can get a sense of how the look of the game changes with the effect removed from the presentation.
Returning to the positives, A Plague Tale is also lit beautifully. Like many other of the slower-paced games we have seen this generation, such as the Order 1886 or Uncharted 4, this new game relies heavily on baked indirect lighting, mixed in with screen-space ambient occlusion and shadow map cascades for its lighting. Like any static solution though, it has its problems with how dynamic objects look in comparison to static ones, as well as problems of alignment and light leakage. But the solution works well for the vast duration. It is really a core reason why this game looks as good as it does - as physically-based materials need a nice indirect lighting pass to take on a life of their own and look their part.
Another fascinating aspect of the game is the vehicle for the plague itself - the multitude of rats. According to interviews, A Plague Tale renders up to 5000 rats on-screen at any moment for gameplay scene. They are really everywhere, squirming and scurrying away from the light of your torch, while swarming onto hapless characters or even your character if you are not careful. Technically, it is quite interesting as the rats are not just cardboard billboard cut-outs, or simplistic geometry that on an aggregate level looks like a swarm of rats. What we get is individually animated rats with moving tails, legs and different animation states. Their exact technical make-up isn't clear, but the way they act when moving around the environment, repelled from light, reminds me of particle fluid simulations or even something like vector fields driving the rats away from bright light sources. It is particularly curious how the the mass of rats boils away into a corner when you move them with a torch - it's not exactly biological looking, but more like a physics tech demo.
A Plague Tale: Innocence is a wonderful looking game then, with individual notes in the presentation rivalling the best out there in the AAA space, all on its own engine. I spent most of my play sessions on the PC version - which at its ultra preset really pushes your hardware, which raises the question of how the console versions compare. The reality is that the compromises are noticeable, but Xbox and PlayStation version are extremely attractive in their own right.
The enhanced consoles target 4K displays, with Xbox One X seemingly using temporal reprojection to take a native 1440p image up to a 2160p output. Asobos pushes this technique still further on PS4 Pro, and less effectively, using a core 1080p image to temporally accumulate to the same target 2160p. Given the game's heavy use of post-processing, this difference in resolution is not that important between the versions. Those areas best helped by the higher resolution such as foliage, hair or distant material texture details make up much less of the game's content than the opaque geometry, shadows and lighting which hold up rather well from the upscaling. Performance is locked at a solid 30 frames per second in every scene I tested on both machines.
The vanilla consoles present a different story. PlayStation 4 delivers 1080p, while Xbox One settles at 1526x864 instead. There's no doubt that the Microsoft base machine falls short of its counterparts, with the most obviously soft image of the bunch. Both of the standard machines also have some performance issues too - most noticeable in foliage-heavy scenes or those heavy with dynamic lighting. At this point, screen-tearing kicks in with some frame-rate drops to the mid-20s. Despite its resolution deficit, Xbox One runs noticeably worse than its PS4 equivalent, but only the Pro and X deliver an absolutely solid turnout in frame-rate terms. The enhanced machines also deliver improved shadow resolution, while the Xbox One X also pushes out draw distances in a way that none of the other consoles match.
Consoles generally tend to operate on equivalents that most closely match the PC's medium preset, and once you start to push settings higher, the burden on graphics hardware rises significantly. Deploy the RTX 2080 Ti at ultra settings and you're looking at an 80 per cent resolution scale (native 3072x1728) to get anything like a consistent 60 frames per second on a UHD display. I also noted some curious stuttering issues: frame-rate analysis of the video output can catch some alarmingly inconsistent frame refreshes, even though internal frame-rate counters suggest a locked 60ps. It's almost as if rendered frames are being eaten, prevented from reaching the GPU video output. It's a relatively rare occurrence - but frequent enough to prove annoying.
Mid-range GPUs show expected scaling based upon Xbox One X and PlayStation 4 Pro performance. At 1080p ultra settings, AMD's RX 580 and Nvidia's GTX 1060 come nowhere close to 60fps and spend much of the time in the 40s, with drops into the 30s. Lowering visual quality to console-level medium does help pushing those numbers up closer to 60fps. Curiously, this is a game where the GTX 1060 delivers superior performance to the RX 580 in completely GPU-limited scenarios - something that hasn't happened for some time in our PC performance workouts on the latest titles.
Wrapping up, I have to say that I really enjoyed A Plague Tale: Innocence and highly recommend that you check it out, especially on PC and the enhanced consoles. It's a stunning game that manages to hold its own from a technological perspective up against some of the best triple-A fare. I'm hugely impressed at how close Asobo Studio's engine competes to the absolute state-of-the-art tech delivered by some of the biggest names in the business - it's really amazing work, and a genuine dark horse that may well be one of 2019's best surprises. And with that in mind, I'm really looking forward to seeing what this studio does next.