Global Illumination in Metro Exodus: An Artist’s Point of View

Why is real-time raytracing the future of lighting in game development? Because it allows artists to create more realistic visuals while simplifying the content preparation process.


Color bleeding is a byproduct of global illumination that makes scenes look more life-like.

Global illumination is a technique made possible with real-time ray tracing. It simulates the way light scatters and bounces in real life.

Earlier this year, 4A Games released Metro Exodus on PC. It’s one of the first titles on the market to feature global illumination. The results are stunning; sunlight looks photorealistic, further immersing players in Metro’s richly textured world.   

At GDC 2019, 4A Games walked attendees through the process of adding global illumination to Metro Exodus on PC. “Ray lengths are fifty-times larger. We are getting an unbelievable amount of rays per-second,” explained Sergei Karmalsky, Art Director at 4A Games. “What’s also important is that we are getting the pixel-perfect details. We are not limited by the scale of scenes.”

4A’s comprehensive hour-long talk covers stochastic effects, DXR integration, deferred lighting for hit positions, and denoising. The full presentation can be found here.

Below, we have provided a 12-minute excerpt, which covers global illumination from an artist’s point of view.

Learn more about 4A’s experiences with ray-tracing by viewing the full talk, Exploring the Ray-traced Future in Metro Exodus”. An NVIDIA Developer Zone membership is required to access this content; registration is free, and it takes less than one minute to complete.

Learn more about 4a Games and Metro Exodus here.