WTF is ray tracing?

It’s gone from Hollywood to your front room, but what will ray tracing do for your gaming?

Ray tracing might sound like the name of a renegade cop who gets results, but it’s been one of the big buzz terms of E3 2019.

With a new generation of consoles on the horizon and more details emerging around both the next PlayStation and Microsoft’s Project Scarlett, it’s inevitable that talk would turn to just how much better the graphics would be from the new machines. And while some will focus on their 8K capabilities, it’s a process called ray tracing that’ll arguably have the most noticeable impact.

But what exactly is this eye-catching graphics tech all about? And do you really need to wait until the end of next year to get a taste of it?

What exactly is ray tracing?

Ray tracing is a way for games to recreate lighting that looks much more realistic than ever before because it simulates the way light travels in real life.

The process generates an image by tracing a path of light (hence the name) from an imaginary eye to every surface or object in the scene. An algorithm then works out how visible light would behave when it hits each one, based on what they’re made of and how many light sources there are available. Reflective surfaces will bounce varying amounts of light onto other objects around them, while anything blocking the path of the light will create dynamic shadows.

This process allows for far more realistic-looking scenes, like the one from Cyberpunk 2077 above, but it’s not just for the sake of eye candy. Sure, you’d have to really be paying attention, but think about how reflections and changes in lighting could give away an opponent sneaking up on you in an FPS.

Which games support ray tracing?

Some of E3’s biggest titles will use ray tracing, including Cyberpunk 2077, Watch Dogs: Legion, Call of Duty: Modern Warfare, Wolfenstein: Youngblood, and Control, but only in their PC versions to begin with. The tech will also be found in indie titles such as Stay in the Light (which is already available on Steam in Early Access form), Enlisted, Justice, and Atomic Heart.

But it’s not just for new games either. Battlefield V, Shadow of the Tomb Raider (below), and Metro Exodus already support it, while Assetto Corsa Competizione is on the waiting list to get an update. Even Quake II (above) has been remastered with the ray tracing treatment and it’s quite amazing how big an impact it has on the look of a game that came out in 1997. The character models still look pretty retro but the environments could have come from a game far younger than Quake’s 22 years.

How do I get it?

Ray tracing requires much more computing power than has traditionally been available to mere mortals, which is why it’s previously been the preserve of Hollywood’s CGI and visual effects departments. But that's all about to change.

Right now, you’ll need a PC with an Nvidia GeForce RTX graphics card to get the best ray tracing performance, although there’s also a patch that enables it on GTX cards. Turning it on will have an impact on the frame rate your games can run at, so it’s worth having as much power at your disposal as possible.

If you think a teraflop is something a dinosaur does in a swimming pool, you’ll probably want to wait until consoles are powerful enough to deal with ray tracing. The good news is that shouldn’t be too far away. Both Microsoft’s Project Scarlett (or whatever they end up calling it) and Sony’s PS5 (ditto) will support the tech and both are expected to be released before the end of 2020.