Ray Tracing; What is it, and Should You Care?

Ray tracing is a term that PC gaming enthusiasts, designers, and more will be familiar with, but is very recent ground when we’re talking about video games in general. Today we’ll be tackling what ray tracing is, why it’s important, and should you even care?

Ray Tracing – What Is It?

So, the first thing. What is ray tracing? Put simply, it’s a rendering technique that ‘traces’ the path of a light source as pixels and calculates and then simulates its effect on objects within the same scene. What it results in is an image that is far more realistic to look at, with shadows, lighting, and reflections sitting much closer to what you would see in real life. If you see an artist drawing a glass ball, and he has a representation of a light source somewhere to reference any shadows, refractions, or reflections – that’s effectively ray tracing, only slower. The target for ray tracing is to generate an image or scene that’s as close to photo-realistic as possible. 

The first thing to note is that ray tracing isn’t just one entity that happened to come around in 2020. It’s been around in some form or another for a while now. CAD (computer aided design) suites have used it for decades, and so have the movie business. The primary difference is the method. Software accelerated ray tracing is primarily used for creating photo-realistic images and scenes and has been in active use since the 1980s. I’ve even used it in some software packages when I was studying design at university. It’s an incredibly powerful tool, if intensive. I distinctly remember one single image taking 3 hours to render. This is why it’s referred to as software accelerated ray tracing; the render is driven almost entirely by your chosen application and CPU.

The big thing, and today’s subject, is ‘real time’ ray tracing. This is the same principle as the above, but applied to a moving object or scene – in this case video games. It’s much more complicated, and considerably more demanding, requiring newer GPUs and APIs to provide the horsepower and tools needed. The act of using a GPU to power the process is known as ‘hardware accelerated’ ray tracing.

You keeping up?

Up until the PS5 and Series X, real time ray tracing has been a rendering technique unreachable by consoles; they simply weren’t powerful enough. The Xbox One X was capable of outputting native 4K and 30fps (occasionally even 60fps), yet still couldn’t hope to ever effectively implement real time ray tracing. It’s only been a relatively recent acquisition for gaming PCs if we’re being wholly honest. Up until very recently you needed at the very least a 2060 to power the process on a PC, a graphics card that would’ve cost you around £300 at launch. My PC runs a 1060 6GB, the card before the 2060, and quite frankly wouldn’t have a hope. 

One of the best examples of real time ray tracing on PC is currently Cyberpunk 2077. It may have struggled for performance on consoles, but high tier gaming PCs showcased the game as originally intended, complete with full ‘global illumination’ techniques that are still relatively new. However, to reach this glorious goal, the minimum recommended for full ray tracing in Cyberpunk 2077 is an Nvidia RTX 3070 graphics card; a £500 card

Is Ray Tracing Worth The ‘Trace’ Off?

So ray tracing is expensive, demanding, and no doubt challenging for developers to implement. But is it worth it? In a word – yes. Ray tracing is the current standard for visual fidelity in PC video games, with most modern titles incorporating it in some shape or form. It’s also an incredibly effective rendering method, pushing and enhancing immersion in even its most basic forms. In fact, in its most efficient usage you shouldn’t even really notice it if you’re not looking for it. In games like Cyberpunk 2077 or Control it’s far more obvious, but in other games it’s more subtle. 

Before ray tracing, developers built accurate-ish reflections into their world based on their assets. It takes a lot less horsepower to render, but they also don’t react to the world around them. They also don’t show things like reflections in reflections, or reflections of off screen objects. They’re static, they don’t react to changes in lighting, perspective, or environment. Ray traced reflections do. I’ve got an example below, taken in Control Ultimate Edition on my PS5. With ray tracing on, the plant on the right hand side of the upcoming room is reflected in the glass office windows on the left. With ray tracing turned off, it’s not, and you lose a lot of other detail as well.

Ray Tracing Turned On
Ray Tracing Turned Off

It’s the sort of thing you won’t notice unless you’re looking for it, or comparing the two shots side by side like we are now, but the difference is startling; especially in a graphical powerhouse like Control. 

What’s The Catch?

Well on PC, if you have the hardware, there isn’t one if I’m honest. Good frame rates are still perfectly achievable at 1440p or 1080p. 4K resolutions, on high settings, require slightly more on the side of your 3070s and 3080s; graphics cards that cost over £500. But that’s a small audience. 

The major catch comes with console play. Ray tracing, on single player experiences anyway, basically forces 30fps. The major exception to this rule is Spider-Man: Remastered and Spider-Man: Miles Morales, but we’ll get around to that very shortly.

How much frame rate matters will come down to the person, and down to the monitor or TV you’re using. Extremely high refresh rate panels (the speed at which your screen is able to refresh the image) can and will show major judder when playing at 30fps. This is mostly due to the sheer performance of the TV. So, take me for example. I’m on a 55 inch LG CX OLED; arguably the best gaming orientated TV currently available. At 30fps games look really poor, until I manually play with the settings and turn stuff on to smoothen it out. At 60fps things look absolutely glorious. This isn’t the fault of the TV (don’t worry, prospective CX owners), it’s the simple fact that the TV is so damn fast.

A lot of this comes down to the person for sure. Some people are far more susceptible to motion blur, juddering, tearing, and other such issues. Heavy motion blur makes my eyes hurt, and I can feel slightly ill from looking at it too long – a huge issue at lower frame rates. Some people will be immune to such issues, it’s all potluck. 

For me, I’ve found RT is worth it in some games, but not others. Before Insomniac released their black magic ‘Performance Ray Tracing’ mode, I refused to play that game at 30fps, it just didn’t look good or play well. Enough that I was happy to drop the excellent ray tracing. Of course eventually they released a mode that allowed ray tracing at 60fps, with some other caveats, so all is well.

The inverse of this is Control: Ultimate Edition that I’ve been playing on PS5. Don’t get me wrong, the game plays brilliantly at 60fps, but the amount of detail and immersion that ray tracing adds to Remedy’s game has to be seen to be believed. So I’m playing almost solely on 30fps, only dipping into 60fps every now and again. The sheer amount of detail in the marble, glass, and other environmental bits and pieces makes sacrificing 60fps easy.

It’s all preference. 

So Ray Tracing – Should You Care?

If you’re on PC and have some spare cash, there’s no reason not to upgrade to a RT capable GPU. It’s a win win. Brand new GPUs are cheaper than they’ve ever been (£500 is a lot, but for the sheer power of the 3070 that’s an excellent price). Although granted you’d struggle to buy a new GPU right now. At the higher frame rates that these graphics cards can drive, ray tracing is very achievable at 60fps or higher. It’s worth the investment now, and it’s only getting better as more and more developers implement it and optimise it.

On console? That’s a harder sell. The fact that, on most games anyway, it forces you down to 30fps in order to achieve the advanced rendering of ray tracing is a tradeoff that many simply won’t care for. 60fps is inarguably the superior frame rate, all the time, so why would you drop down?

For me it’s situational. I’m a tinkerer, I like playing with the quality options, seeing what looks best in each game. I actually get annoyed when games don’t include quality options. More casual consumers might not be like this. 

The other issue is that the RT on Xbox Series X and PS5 is inferior to that on high end PCs. There’s no way of skirting around it. Most console examples of RT don’t process reflections ‘infinitely’, for example. After a certain distance Spider-Man will replace reflected buildings with lower res and differently shaped alternatives to ease up its load. Many games won’t render reflections within reflections. While both new consoles from Sony and Microsoft are incredibly powerful for their price point, they still have their drawbacks. 

If you’re a console gamer asking “is ray tracing a worthy enough reason alone to upgrade my console?”, the answer is no. It’s an excellent commodity, and it’s honestly impressive that the consoles can power hardware accelerated ray tracing at all, but no. Don’t fork over £450 for a brand new console for ray tracing alone. Instead, upgrade for the native 4K and 60fps, for the rapid loading times, and for the reduced noise signature.

Ray Tracing Turned On

 

Turned Off

Ray tracing is excellent on the new consoles and especially PC, and is stunning at times. Games like Control: Ultimate Edition look absolutely draw dropping. But I’m a bit of a geek for this kind of thing, so it’s all down to preference. 

Hopefully I’ve helped out here today. I could’ve touched on the differences between ray tracing and ‘screen space reflections’ and more besides, but didn’t want to drag on too much. If you did find this helpful, please let us know! Alternatively, check us out on Twitter and Facebook, and don’t forget to read our other pieces! Until next time, have a fantastic week!

Leave a Reply

Your email address will not be published. Required fields are marked *