There’s no doubt that Cyberpunk 2077 is currently the most technologically advanced game available. The first-person open world RPG/shooter was already packed with ray tracing when it launched in late 2020, but CD Projekt RED kicked it all up a notch with last month’s release of the path tracing technology preview, also known as RT Overdrive Mode.
Arguably the main addition was RTX Direct Illumination. Originally unveiled by NVIDIA at GTC 2021, RTXDI enables a much greater number of dynamic lights casting rays at the same time. Here’s how it affects the Cyberpunk 2077 path tracing technology preview, as CDPR’s Jakub Knapik explained in an exclusive interview with Wccftech.
RTXDI is responsible for Direct Illumination, which means it’s responsible for giving information about the light that comes from a source and hits a surface. Previously, shadowing used to be a very painful part of the process. In games, we use a shadow budget, meaning that we can only cast shadows from carefully selected lights in our game. In many cases, we also use very inaccurate shadow maps. So imagine a busy street, with only a few lights capable of casting a shadow, while most of them just light through objects, making them look very unrealistic and disconnected from the surroundings. With RTXDI, we get up to a thousand or even more lights casting super realistic soft shadows on the screen. Practically every light you see casts shadows. That is a fundamental change in realism, depth of the scene, and dimensionality. But it is also a critical element if we assume that every light source, be it a lamp, neon, or screen, is emitting an Indirect Illumination, meaning light that bounces off of surfaces in the world. Without proper shadows in the Direct Illumination part, the Indirect Illumination part would feel totally off and unrealistic. Connecting both parts allowed us to push Path Tracing as realistically as possible.
In the same interview, Knapik revealed the studio’s goal to continue improving the already impressive Cyberpunk 2077 path tracing technology preview. One example he made was introducing support for Opacity Micro-Maps, a hardware feature available on RTX 40 GPUs that can further boost ray tracing performance.
However, in a rumor shared by CapFrameX (creator of the eponymous benchmarking software), CD Projekt RED may be working on adding support for Neural Radiance Cache. This would be very surprising since NVIDIA only recently presented NRC at GTC 2023.
Still, it would be great news if it were true. NRC can speed up path tracing by using Tensor Cores to predict radiance in the scenes, thus allowing most of the rays to be terminated early and saving performance.
While Cyberpunk 2077 already runs great on RTX 40 GPUs thanks to DLSS 3, Neural Radiance Cache should work on any GeForce RTX graphics card since it relies on Tensor Cores. Previous generations could definitely use a performance boost under path tracing.
Cyberpunk 2077 will get its first and only expansion, Phantom Liberty, later this year. CD Projekt RED already said it would be showcased at the upcoming Summer Game Fest, streaming live on June 8th from Los Angeles.
