When NVIDIA announced its new line of GeForce RTX cards in 2018, and the new Turing architecture, the hardware company and pioneer took a forward-thinking and cutting edge idea and made it a reality. The ability to render real-time images using ray-tracing for lighting effects like shadows, reflections, and global illumination.

Digital Ray-Tracing: A Primer

When it comes to explaining graphics technology it’s hard not to get a little technical and dive into terms like Tessellation, Bilinear Filtering, Anti-Aliasing, and Vertexicles. A sea of hard to grasp terminology - so much so, that we made that last one up. There’s no such thing as a Vertexicle.

Ray-tracing is a little different than most other technical effects, in that explaining how it works one only needs to ponder how light in the real world behaves. Beams of light or rays spread out in all directions, passing through objects, reflecting, amplifying, and casting shadows. Turn your back to a bright open window, you can see the effect of the light being absorbed and reflected by any number of objects directly in front of you. Close curtains or blinds and the few remaining rays vie for your attention.

In terms of the computational power required to simulate these light rays in a digital scene, the cost is so great that it’s one of the main reasons highly detailed computer animation can take several hours to render even just a few frames. Getting the realistic effect to run in real-time, in the fast-moving ever-changing environment of a game? That’s the game changer.

At the time of the RTX debut later that same year, full integration into the PC platform was still months away - but with dedicated hardware RT cores and AI-based Tensor cores, cards like the NVIDIA GeForce RTX 2080 were ready to usher in a new era for real-time graphics.

Being the first no doubt has its perks, as well as its shortcomings. The most notable perk being the fact that we now sort of associate real-time ray-tracing in games with NVIDIA’s RTX line and the GeForce line-up of graphics cards. The downside being that as relatively new tech, not that many games offer the ability to render real-time ray-tracing effects. Or, to borrow big green’s shorthand - to go ‘RTX On’.

With the next-generation of consoles from Sony and Microsoft on the horizon, that are set to support hardware based ray-tracing effects (via AMD’s new still-to-be-released RDNA 2 architecture), now's the perfect time to rank ray-tracing in games today. And what each game brings to the digital table.

9. Call of Duty: Modern Warframe (Infinity Ward/Activision)



When it was announced that Call of Duty would be taking advantage of cutting ray-tracing tech for the release of Modern Warfare there was genuine cause for excitement. Here, the most realistic and gritty looking entry in the popular and long-running shooter franchise was set to become, well, more of that. Thanks to fancy new ray-tracing. But with RTX or ray-tracing implementation in Modern Warfare limited to how the game renders shadows, the end result errs on the side of subtle to sometimes barely even noticeable. And that’s because shadow effects in modern AAA releases are better than they have ever been. Subtlety aside, Call of Duty: Modern Warfare with RTX On does net you more realism and a more natural look to shadow detail and diffusion in an already visually stunning game. It even goes as far as to remove improperly calculated shadows and shadow maps with the feature turned off. With ray-tracing turned on we get to see shadows that we thought were realistic disappear entirely as actual rays of light do their thing - all in the name of accuracy.

8. Shadow of the Tomb Raider - (Eidos Montreal/Square Enix)



Like Call of Duty and the word that kicks off the title of the latest Lara Croft adventure, the development team at Eidos Montreal has also opted to limit the real-time ray-tracing in Shadow of the Tomb Raider to the realm of shadows. And like Call of Duty: Modern Warfare the end result isn’t so much ‘holy moly’ groundbreaking as it is ‘hmm… I see’ groundbreaking. Something you’ll only really begin to appreciate when you’ve got those handy before and after shots to make a comparison. Even then your reaction won’t be Jenny Craig commercial levels of before and after stunned, instead you’ll notice how the softer and more natural shadows add more depth and realism to each scene. Diffusion, perceived depth, and how it can make certain objects feel more natural just sitting there in the world. Shadows play an important role in interactive digital environments so having them go the ray-traced route is a definite peek into the future. Especially in scenes with multiple light-sources and a shifting perspective.

7. Stay in the Light - (Sunside Games)


Created by one-man studio Sunside Games, Stay in the Light is an ambitious project that gives us a glimpse at the future of indie development. By having things like shadows, reflections, global illumination, and other lighting effects handled and calculated in real-time and ray-traced it alleviates the need to pre-light scenes, rooms, create detailed shadow maps, or otherwise spend huge resources into making a game look as good as it can be. For as high-tech as it sounds, once ray-tracing becomes mainstream it will be indie studios that might benefit the most. As an old-school dungeon adventure crossed with fantasy horror, Stay in the Light uses ray-tracing for all of its lighting, even going so far as to use reflections in a mirror to render environments, objects, and even potential nightmarish creatures that are situated behind you. The only real thing holding the experience back is that outside of ray-tracing the overall mechanics, and general presentation is fairly standard. That said, with ray-tracing effects there’s a cinematic quality to the game that is hard to not be impressed by.

6. Battlefield V - (DICE/EA)



EA and DICE’s Battlefield series, and the Frostbite engine, has always been at the forefront of graphics technology. So it’s fitting that Battlefield V would become the first game to implement ray-tracing effects that took advantage of the RTX line, for reflections. Creating for the first time a situation in a multiplayer and cinematic shooter where you could see an enemy combatant in a reflection as they’re approaching from around a corner that wasn’t already visible. Up until Battlefield V, reflections in games could only reflect objects already on-screen - which is why the technique is called screen-space reflections. Being able to reflect the sky and planes flying overhead as you’re gazing into a puddle is the sort of next-gen effect that immediately sells ray-tracing as something that will push the industry forward.

5. Wolfenstein: Youngblood - (MachineGames/Arkane Studios/Bethesda)



Also sitting in the first-person shooter space, Wolfenstein: Youngblood implements ray-tracing effects to allow for realistic reflections across multiple surfaces. Where Battlefield V’s implementation was the first of its kind, Youngblood takes everything a step further so that enemies, weapon effects, fire, and even transparency are all present. That means you can see flames reflected in the window of a bus whilst also being able to see the seats through the very same window. Of course filthy Nazis sat in those seats but the effect is still breathtaking and a big step over playing the game with ray-tracing turned off. With Youngblood’s RTX implementation arriving in 2020 it also benefits from NVIDIA’s advanced AI-based DLSS rendering to ensure that even on an RTX 2060 the game will run silky smooth at well over 60 frames-per-second at 1080p.

4. Deliver Us The Moon - (KeokeN Interactive/Wired Productions)



This indie sci-fi adventure from indie studio KeokeN Interactive presents nothing short of a stunning use of real-time ray-tracing for various forms of reflection effects and shadows. With opaque reflections being a showcase for reflections that don’t involve seeing crystal clear images of things. What opaque means is that objects like furniture, and rougher surfaces that might not be entirely reflective, will reflect the light of different sources - adding a level of realism. An effect that is perfect for the sci-fi genre by the way. Plus, transparent reflections that add immediate immersion into a tale of isolation, mystery, and awe. In Deliver Us The Moon when you're alone on a deserted base on the lunar surface and gazing out of a window to view the bright but barren landscape made up of dust and rock - with RTX On you also see the faint reflection of your space-suit and the cold clinical environment of the simple module located behind you.

3. Quake II RTX - (NVIDIA/id Software/Bethesda)



Quake II RTX is essentially the same classic id Software shooter we all played back in 1997. Or, that game we’ve heard an old timer talk about when our own memories of the first-person genre goes all the way back to Halo 4. Ahem. The difference here is that Quake II RTX plays like the memories of playing OG Quake II at launch - those rose-tinted recollections of a classic shooter that are now even prettier today with RTX well and truly On. What started as a proof-of-concept pet project has today evolved into a three-quarter-fledged remaster that’s a great way to showcase the illuminating perks of ray-tracing. Best bit: you can take the opening levels for spin without spending a cent (beyond the requisite GPU, of course). Control the time of day to shine a light - pun fully intended - on yesteryear id’s love of brown. But it doesn’t stop there. Take a dip and marvel at the frickin’ god rays in reflections, then appreciate the frackin’ refractions of glass. An even neater touch is the reflected player character, complete with not-so-great reload animation, in the various monitors that litter the alien home world. The January 2020 version 1.3.0 patch introduced a photo mode (with depth of field effects) whose results are particularly impressive for a 23-year-old shooter.

2. Metro Exodus - (4A Games/Deep Silver)



The post-apocalyptic Russia of the Metro series is steeped in Eastern European architecture, desolation, and the feeling that the entire world has all but disappeared. Metro Exodus, the latest entry in the series, presents vast open areas to explore across various landscapes across different seasons. Ray-tracing here is all about using the technology for Global Illumination (which has been updated in the latest expansion), that is how an environment is lit based on things like the position of the sun or whatever the main source of light might be. It’s subtle in what it adds to the scene but slowly becomes a revelation the more you play - the more realistic lighting and shadows adds to a seamless quality that is purely cinematic. So when you go outdoor or indoor you lose the feeling of playing a game, the lighting always feels natural and with that the experience itself becomes that much more immersive.

1. Control - (Remedy Entertainment/505 Games)



It’s tough to go back to other ray-tracing games once you’ve experienced its ambitious implementation in Remedy Entertainment’s latest. Instead of opting for one or two uses for ray-tracing, Remedy’s Control uses it all to make its game world pure next-gen. Control is without a doubt ray-tracing’s killer app. It does shadows, reflections, and surface lighting better than any game currently available to play. The once claustrophobic underground facility that makes up its environment has increased depth with ray-tracing turned-on, upping the immersion factor and the impressiveness of the stunning art direction. Also, reflections do wonders for a game with a heavy dose of cinematic action. To put that into context, the reflections are so good in Control that we used them to scan rooms for threats before we entered them. Naturally, enemies can also destroy the glass, which eliminates the advantage. Being able to quickly scan through the glass for items of interest while also checking a reflection in the same glass for threats is the kind of ray-tracing gameplay implementation we didn’t know we needed. Ultimately, Control’s ray-tracing elevates the tech beyond mere tech demo and weaves it into fabric of a truly brilliant game.

This list will update over time as more titles and ray-tracing updates are released - which means we’ll have to wait and see just where Minecraft’s RTX update and Cyberpunk 2077 fit in.

Feature co-written and maintained by Kosta Andreadis and Nathan Lawrence