A shader is a piece of code that tells your GPU how to render light, shadows, and color. The "ReShade Ray Tracing Shader" is technically a screen-space ray tracing effect, often abbreviated as (Ray Traced Global Illumination). RTGI Explained: Why 0.33 is a Legend Developed by the brilliant Pascal "Marty McFly" Gilcher, the RTGI shader simulates how light bounces off surfaces in real-time. Unlike traditional ambient occlusion (which only adds shadows in corners), RTGI calculates the intensity of incoming light and its color bleed. For example, a red brick wall will cast a faint red tint onto a white floor nearby.
For a free tool that runs on almost any GPU from the last 8 years, RTGI 0.33 is a miracle. In static screenshots, it is often indistinguishable from RTX 20-series ray tracing. Final Verdict: Is RTGI 0.33 Still Worth It in 2025? Absolutely. While Marty McFly has moved on to paid "True Illumination" shaders costing $5/month, RTGI 0.33 Free remains the best entry-point into realistic lighting for budget PC gamers and modders. reshade ray tracing shader rtgi 033 free
Navigate to the "Home" tab. In the search bar, type "RTGI". You will see the shader appear. Click the checkbox next to it. If done correctly, your screen will suddenly look darker, with rich bounce lighting. A shader is a piece of code that
The effect flickers or looks like "soup." Solution: Screen-space ray tracing requires a depth buffer. Go to the ReShade "Add-ons" tab and ensure "Copy depth buffer before clear" is checked. Also, disable anti-aliasing in-game (use ReShade's SMAA instead). In static screenshots, it is often indistinguishable from