What Is Ray Tracing? 

What is ray tracing

Simple Answer: Ray Tracing creates images by tracing simulated light in a logical path.

Although modern day video games look amazing, the truth is that we have hardly begun to scratch the surface in terms of what they could look like, and in how responsive they are.

The technology which is going to take gaming to the next level visually is called Ray Tracing. It’s become a reality thanks to the new range of Nvidia RTX cards.

So, what exactly is Ray Tracing, and how does it work? Well, let’s try and break down the complexity to give it to you straight.

We will take a look at what is, how it’s rendered on the screen, plus whether it’s worth the money upgrading to one of the new Nvidia RTX cards now.

Polygon Mesh

How Games Are Displayed

Video games use rasterization to render images on the screen. It’s a great way to convert 3-D images into two-dimensional animations, based on pixels.

The problem with rasterizing images is that it then has to employ shaders to produce even half decent lighting effects, shadows, things like that.

In even the most advanced games you’ll notice that shadows and reflections just aren’t always up to the standard you’d want. They just aren’t always convincing.

Early rasterization used hundreds of polygons to create the images. However, we are now in a world where graphics cards are capable of generating literally millions of polygons. Then rasterization is used to build the 2-D image.

So, it’s effective, manageable, and even modest computers can process the polygons efficiently. But the problem still remains: shadows and reflections just do not render well to create a convincing 3-D world.

Reflections

Ray Tracing Explained

The strange thing is that Ray Tracing has actually been around as a concept for about 50 years.

A guy called Turner Whitted actually wrote a paper back in 1979, titled “An improved illumination model for shaded display”.

You probably won’t be shocked to learn that Turner Whitted now works for Nvidia.

The simplest description of Ray Tracing is that it creates the images by tracing simulated light in a logical path.

Actually, it’s doing it for millions of different simulated lights, all at same time.

In the real world, light particles are bouncing around all over the place, billions of them. Ray Tracing attempts to recreate that by bouncing and interacting with the properties in the graphics.

Because of its similarity to the way that light works in real life, Ray Tracing is a very realistic rendering method. But the problem is it’s complexity has meant it simply hasn’t been to utilize it in your average home gamer PC, until now.

Related: How to build a gaming PC

Ray Tracing has actually been around as a standard technology in the movie industry for quite some time.

It’s what they use to create the amazing CGI work, where real life is blended into the generated graphics.

However, as you’ve probably already guessed, it’s incredibly intensive work. It requires very powerful machines, and server farms, to create that level of image complexity.

Ray tracing Explained

Which is where the new Nvidia RTX 2000 series of graphics cards come in. They’ve changed the game when it comes to Ray Tracing being a viable home computing technology.

They include hardware and software specially designed to cope with using Ray Tracing.

Using the company’s new Tensor cores, it’s now possible to handle something approaching the complexity of film generated shadows and reflections on a desktop PC.

The result is beautiful reflections, and highly defined, realistic shadows. Effects that change depending on where they are bouncing to, or moving away from.

Two current games where you can see Ray Tracing in action, are Shadow of the Tomb Raider, and Battlefield V.

Shadow of the Tomb Raider has some amazing shadows within it, that are brilliantly refined, accurate, and effortless.

Battlefield V, to continue the example, is more about reflections. You can see the reflections of terrain on the aircraft, reflections in windows, and even the reflection of explosions that render perfectly.

Ray tracing on vs off

Hybrid Rendering

Where Ray Tracing technology is being focused right now is in something called hybrid rendering.

For years, hardware and software in the gaming industry has focused on producing faster rasterisation.

But it’s always been the issue that shadows and reflections, plus some types of light, just don’t look good when they are being recreated purely using rasterization.

Various techniques have been used to try and get around this, including things like shadow maps, which are used in a lot of games right now.

But the problem is these are very memory intensive.

What hybrid rendering does is to blend today’s rasterization methods with Ray Tracing.

Rasterisation is what renders the polygons, and it’s then combined with shadows and reflections created using Ray Tracing.

So it’s a hybrid method, where the trade-off is between performance and quality. The more Ray Tracing that is done, the better it looks, but you need higher frame rates and better hardware.

Read also: How to improve your FPS in games

Remember we mentioned Nvidia’s new Tensor cores within its RTX range?

Well, what these do is to accelerate machine learning calculations.

This allows a much faster rendering on the screen, and a much deeper representation. It allows high rasterization, but still leaves enough processing power to allow each pixel to have 80+  rays.

Cards That Can Accelerate Ray Tracing

The only graphics cards currently available that can use Ray Tracing are the Nvidia RTX 2000 series ones. These are very expensive graphics cards with the RTX 2080 Ti as the top of the line model costing well over $1000. But the RTX 2080 can be picked up for about $400 less.

You can find the top models in each of the following guides:

Top rated 2080 Ti graphics cards
Best RTX 2080 buyer’s guide
Best RTX 2070 buyer’s guide
Best RTX 2060 buyer’s guide

Furthermore, the RTX 2070 and RTX 2060 are far more affordable but still come with ray tracing.

Even worse than that, right now, there are only about 30 games that actually have, or plan to have support for Ray Tracing.

However, look 12 months down the line, and as with most technological jumps, prices will come down.

It will become a universally embraced technology, and a huge leap forward for gaming graphics.

You can be assured that Ray Tracing will become an industry standard pretty soon.

Disney Pixar have already produced several films using a deep learning tool on generator graphics. When one of the kings of graphics is using this technology, the domestic market will not be far behind.

On top of that, the big boys out there, AMD, Microsoft, and Intel are all looking at Ray Tracing technology.

AMD for example, have announced “real-time Ray Tracing” through a new rendering engine called ProRender.

So, the future is here, but if you’ve got the money for an RTX card and you don’t mind the limited game support.

But you could certainly bet your house on Ray Tracing becoming an industry standard game rendering technology pretty soon.