: Download the setup from Reshade.me and run it. Select your game's executable (.exe) and choose the appropriate API (DirectX 9/11/12 or Vulkan). Add RTGI Files : Download the ReShade GI Beta 0.17.0.2.zip from Patreon.

Because it works via ReShade, it can be applied to hundreds of DirectX 9, 10, 11, and 12 titles, regardless of the user's GPU brand (NVIDIA or AMD). To help you further, RTGI 0.17.0.2 Release! - Patreon

In simpler terms, it simulates how light naturally bounces off surfaces to illuminate a scene. It calculates diffuse global illumination, meaning light from one surface softly illuminating another, and also handles more direct specular reflections.