“Ray Tracing is the future, and the industry is ready to implement it” – 4A Games while talking about the recent Metro Exodus update

metro exodus ray tracing is the future

On May 6, the PC version of Metro Exodus received a re-release in which the developers removed the baked light and added RTGI. This update will be available soon for the next generation of consoles. In honor of the launch, Metro Exodus developers gave Digital Foundry a long technical interview. In the interview, Jon Bloch mentioned the importance of Ray Tracing in games and that the industry is ready to adopt it.

Technically Metro Exodus is still not a fully patched game. This is a hybrid in which global illumination, lights and shadows are ray traced and everything else uses traditional rasterization techniques.

Metro Exodus: Enhanced Edition is the first step towards the future of Studio 4A, which in the future will probably no longer release games without support for ray tracing.

Ray Tracing is the future, and the industry is ready to implement it" - 4A Games while talking about the recent Metro Exodus update

The team wanted to update Exodus when it was announced that next-gen consoles would receive Ray-Traced Global Illumination (RTGI) support. At the same time, they decided to refresh the PC version in order to use the capabilities of more powerful video cards.

Almost all of our departments were involved in this update, but it was the programming that required the most. The artists had to go back, remove the fake lights, and then polish and rebalance the scenes. The designers needed to make sure that light-based systems like stealth still work. It was not a quick and by no means an easy undertaking, but we knew that such an opportunity was too good.

Jon Bloch
Executive Producer – Metro Exodus

According to Jon Bloch, ray tracing, like other fully dynamic technologies, will positively affect the artistic side of games. When a developer sees the result of his actions with a long delay, he begins to be cautious.

If you need to bake a light or start some very heavy update process, it will take time for you to see even a small change. It’s iteration time. It can break the entire development process.

A second or a few seconds is fine, developers can live with it. When it comes to 5-10 seconds, people start to take fewer risks and miss out on interesting changes that can make the game better.

When you have time to go for coffee, the whole process falls apart. Ideally, you should see the result immediately. That is why we are so focused on making all our graphical features work in real-time.

Jon Bloch
Executive Producer – Metro Exodus

But the main feature of the Enhanced Edition for the team is the ability to simply remove all fake lighting.

Very often, as a stylistic solution, the artist needs to put a soft light that has no real source, or to highlight an entire area. This is usually done to achieve a natural light effect.

Now, this is all done automatically. Light “bends around corners” thanks to DDGI (Dynamic Diffuse Global Illumination) and gradually penetrates into dark areas, which are not hit by direct rays. All this big work can now be done with basic lights – and more realistically.

Jon Bloch
Executive Producer – Metro Exodus
Ray Tracing is the future, and the industry is ready to implement it

As Bloch notes, the developers barely had to touch the art itself. Somewhere they improved the quality of the textures, and somewhere they applied spark effects, which were previously only used for a flamethrower. The work on the Enhanced Edition was to apply ray tracing to the finished art, and then tweak it in such a way that the game looks aesthetically close to the original.

The developers also confirmed that the next game in the series will better balance open and linear levels.

The open-ended levels that appeared in Exodus were a big success, but the classic linear locations in the game have diminished. This was noticed by both fans and the developers themselves.

We guarantee that in the future we will keep both, but we will strike a balance, while simultaneously expanding the richness and complexity of our levels.

Jon Bloch
Executive Producer – Metro Exodus

Bloch believes projects like the Enhanced Edition are still a risk, but more games will rely on ray tracing in the future.

As far as DXR was concerned we went all-in with unfettered enthusiasm as soon as we realized we could. It really is the future, and with the introduction of support to Gen 9 consoles, it has proven that the industry is ready to commit.

It takes people to give life to new technology like this, and we have already realized that we are far from alone. We took some risks by making the first game that doesn’t work without ray tracing (right?), But we think the obvious benefits outweigh it – both for the development process and for gamers.

Jon Bloch
Executive Producer – Metro Exodus

As for the implementation of DLSS 2.1, the team decided to wait for a full-fledged re-release for a reason. The process of incorporating this technology into the game itself is simple, but 4A still needed to change some features of its pipeline in order for the neural network upscale to work correctly.

Ray Tracing is the future

Implementation of VRS, Shader Model 6.5, 16-bit FPP turned out to be quite simple for developers. For example, the first one in the game is used for transparency effects, which only slightly simplified the pipeline.

It took months to implement dynamic diffuse global illumination (DDGI), but it was our only option for secondary global illumination. In addition, the effect is visible throughout the game, so we have raised the priority of this task.

Reflections are the only thing that we had to be flexible in terms of graphs. This is one of the most voracious features, and in order to get it right, we had to completely rework a lot of the engine’s features – not just lighting. They were second only to global coverage in terms of importance in our game.

Jon Bloch
Executive Producer – Metro Exodus

According to Bloch, in terms of gameplay, all versions of 4A games are equal, but the team still uses the PC as a testing ground for new technologies – because computer hardware is developing faster.

The 9th generation consoles are an incredible achievement, and there hasn’t been better timing for us than now to show our fans the ray tracing technology and pave the way for future studio projects.

We were worried for a long time that the new consoles would not have ray tracing at all – due to the economy. We were afraid that we would have to support two different classes of technology at the same time. But this feature has appeared, and it is invaluable for us – now we know that we can continue the road to the ray tracing future.

Nevertheless, the stability of the consoles cannot override the flexibility and possibilities for experimentation on the PC for us. Especially when it comes to iterative development. It’s easier to do it on a PC first because you’re working on a PC.

Jon Bloch
Executive Producer – Metro Exodus

Bloch noted that the Enhanced Edition first came out to PC because it was a free update – it was published at the time it was ready. In addition, certification is still required on consoles. With a full release, the studio would have acted differently.

In the case of a regular release, we did it differently. Focus on the consoles and get them ready and then finish with the PC while the certification process goes on. But this time the order turned out to be different, and we decided to find our advantages in it.

Large global multi-platform releases usually need to be ready on all platforms at the same time – you want everyone to be able to purchase on the same day. This is a free patch, so we didn’t have the usual restrictions.

John Block
Executive Producer – Metro Exodus

The Enhanced Edition will be released on consoles on June 18th. Earlier, Digital Foundry took a detailed look at its PC version.