PCGH: Since we last saw a live build of Cyberpunk 2077 at Gamescom 2019 you've added quite a lot of new ray tracing effects, for example reflections and indirect illumination. And since this is your own engine and you presumably also work on your own tools for it: How hard is it to implement ray tracing into a game-engine? "The implementation of ray tracing (...) proved to be quite a challenge."Lead Graphics Programmer Marcin Gollent also reveals that the game requires DirectX 12 support due to the decision to go with DXR (DirectX Raytracing).
Jakub Knapik: Overall, the implementation of ray tracing into the game engine on a practical level, with all the needed parity and care for our in-engine systems, proved to be quite a challenge. That said, I think the difficulty is something that's very case-dependent. Every engine is molded to serve specific needs. Our own was set up to enable us to depict the incredible complexity of Night City, with its vast verticality and enormous amounts of assets across the city. All that with dynamic global illumination working in real-time with all local lights, a dynamic day and night cycle, as well as changing weather states.
This means Cyberpunk 2077 will only work on DX12 operating systems, which is basically Windows 10 but also Windows 7 as the latter received DX12 support last year. Windows 8.x users are left in the cold, but that shouldn't be a major problem as few gamers use that version of Windows. CD Projekt RED aims to release Cyberpunk 2077 on November 19, 2020.