4A Games har for vane at skubbe lidt til grænserne hvad angår grafisk realisme i spil, og de har da også tidligere afsløret, at de ønsker at komme tilbage til at "sprænge grafikkort i luften" med udgivelsen af det kommende Metro Exodus. Derfor dukkede repræsentanter fra udvikleren op ved GDC for at vise en særlig teknisk demonstration frem.
Demonstrationen skete i samarbejde med Nvidia og deres nye RTX-teknologi. Du kan se demoen herunder, og under denne finder du 4A Games' tekniske chef, Oleksandr Shyshkovtsovs forklaring på præcis hvordan de bruger teknologien.
"For many years, proper global illumination has been the holy grail of real-time rendering. There have been various solutions in the past, but all have had to compromise in some critical area.
Offline pre-rendered GI offers a great visual target, but sacrifices flexibility in production, in-game dynamics, and uses a lot of memory. Prior realtime solutions were always limited by distance of light propagation, lack of data behind objects or screen edges and produced visual issues like leaks or unnatural lighting.
But this is the point where hardware steps in bringing truly scale-independent ambient occlusion by allowing brute force tracing of multiple rays from each pixel several hundreds of meters each frame.
Dynamic lighting has always been a priority for the Metro series. We intentionally avoided pre-baked data and were relying on real-time methods to build our visuals to support more flexible, dynamic gameplay. Global Illumination is highly important for the proper "grounding" of objects and readability of shapes, which in turn create improved ease of navigation and enhanced visual impact for the player.
Previously, we had utilized a mix of several custom-made systems to satisfy our hungry demand for dynamic content of varying scale. Now we are able to replace it with one single system that covers all our needs and outputs the quality of offline renderers."