Reshade Ray Tracing Shader Rtgi 0.33 May 2026

Ray Traced Global Illumination (RTGI) shader, developed by Pascal Gilcher (Marty McFly), is a sophisticated post-processing effect for ReShade that simulates real-time global illumination and ambient occlusion in almost any game. Unlike native ray tracing, it operates in screen space by tracing rays against the game's depth buffer, making it compatible with non-RTX GPUs. Key Features of RTGI 0.33

Released around August 2022, version 0.33 introduced several significant technical improvements: Motion Vectors Integration

: This was the standout feature for 0.33, allowing the shader to track movement between frames. This drastically improves temporal stability, reducing the flickering and "ghosting" artifacts common in earlier screen-space solutions. Enhanced Denoising

: Utilizing motion data enables more effective denoising, resulting in smoother lighting transitions and cleaner shadows. Hardware Independence

: It continues to work across a wide range of hardware, though it is demanding on performance due to the complexity of the calculations. Visual and Performance Impact Realistic Lighting

: RTGI physically simulates light bounces, adding depth to scenes that otherwise look "flat". It adds subtle glow beneath light sources (like portals in ) and accurate shadows at material edges. Performance Cost

: While more efficient than early versions (which could drop FPS from 60 to 15), RTGI is still resource-intensive and can significantly impact frame rates depending on the game and settings. Depth Buffer Requirement

: The shader requires a properly configured depth buffer to work. Users must often manually adjust settings like RESHADE_DEPTH_INPUT_IS_INVERTED RESHADE_DEPTH_INPUT_IS_LOGARITHMIC to ensure the shader "sees" the game world correctly. How to Access and Install The RTGI shader is distributed through the Marty's Mods Patreon

, typically requiring a "Breakfast" tier membership ($5) or higher for beta access. Portal Reshade RTGI - The Working Class' RTX Portal Reshade Ray Tracing shader RTGI 0.33

The RTGI (Ray Traced Global Illumination) shader by Pascal Gilcher (Marty McFly) is a post-processing tool for ReShade that simulates path-traced lighting, shadows, and ambient occlusion in almost any DX9, DX11, DX12, or Vulkan game.

As of version 0.33, the shader has been optimized for better performance and includes specialized features like infinite bounces and advanced denoising. 1. Requirements & Prerequisites

Before installing, ensure your system and game meet these criteria:

Access to the Shader: RTGI is a paid shader available through Marty McFly’s Patreon. Download the latest version (0.33 or newer).

Depth Buffer Access: The shader requires access to the game's "Depth Buffer" to know where objects are in 3D space.

Note: Depth access is usually disabled in online multiplayer games to prevent cheating.

ReShade: Download the latest version from the official ReShade website. 2. Installation Steps

Install ReShade: Run the ReShade installer, select your game's .exe, and choose the correct API (usually DirectX 11 or 12). When asked to select effect packages, ensure "Addon" support is enabled if you are playing a single-player game (this helps with depth buffer detection). Add RTGI Files: Open your game's installation folder (where the .exe is). Find the reshade-shaders folder. Copy the RTGI.fx file into the Shaders subfolder. Ray Traced Global Illumination (RTGI) shader, developed by

Copy the RTGI folder (containing textures/headers) into the Textures subfolder. Launch the Game: Press Home to open the ReShade overlay. 3. Configuring the Depth Buffer

If the lighting looks "broken" or follows your camera, you must fix the depth buffer: Go to the Add-ons tab in ReShade. Check the box that matches your game's resolution.

In the Edit Global Processor Definitions (Home tab), ensure:

RESHADE_DEPTH_INPUT_IS_REVERSED is set to 1 or 0 (try both until it looks right). RESHADE_DEPTH_INPUT_IS_UPSIDE_DOWN is usually 0. 4. Tuning RTGI 0.33 Settings

Once active, adjust these key parameters in the ReShade menu:

Ray Length: Controls how far the light travels. High values create large, soft shadows; low values create tight ambient occlusion.

Ray Amount: Higher values reduce "noise" but significantly impact FPS.

Infinite Bounces: A feature in newer versions that allows light to bounce multiple times, creating much more realistic interior lighting. Reshade 5

Denoising: Ensure the denoiser is active to smooth out the graininess inherent in real-time ray tracing. 5. Common Troubleshooting

Flickering Lighting: Usually caused by a "temporal" setting in the game (like TAA). Try disabling the game's native Anti-Aliasing.

Shader is Invisible: Ensure the depth buffer is working. Use the DisplayDepth.fx shader to check; if the screen is solid black or white, RTGI cannot "see" the 3D world.

Performance Hits: RTGI is very demanding. If your FPS drops too low, reduce the Resolution Scale within the RTGI settings to 0.5 or 0.67.

3. Better Depth Buffer Handling

One of the biggest headaches with ReShade is getting the mod to understand what is a wall versus what is the sky. Version 0.33 includes smarter automatic depth buffer detection for DirectX 9, 10, 11, and 12 titles. Fewer crashes, fewer pink screens.

Prerequisites

1. Reshade 5.0 or higher installed on your target game (e.g., Skyrim, GTA V, Fallout 4).
2. RTGI 0.33 Shader files (Look for the .fxh and .fx files specifically named "RTGI").

Best-case games:

• Dark / moody games (Dishonored, Thief, Resident Evil remakes) — the bounce light fills shadows with color from nearby surfaces.
• Static camera or slow-paced games (Disco Elysium, XCOM, Civ) — temporal accumulation works perfectly.
• Older games with baked lighting (Mass Effect Legendary, BioShock) — RTGI adds dynamic bounce light where none existed.

Part 2: Is it Real Ray Tracing?

This is the million-dollar question. No, RTGI 0.33 is not hardware-accelerated BVH ray tracing like you get in Cyberpunk 2077: Overdrive.

However, it is ray tracing—just mathematical rather than hardware-based.

• How it works: The shader traces rays only from the visible pixels on your screen (Screen Space).
• The Limitation: Because it cannot see around corners or behind the camera, you will get light "leaks" or inaccurate reflections at the very edges of the monitor.
• The Magic: Despite this limitation, in 90% of gameplay, RTGI 0.33 convincingly creates bounce lighting, ambient occlusion, and indirect shadows that transform flat, matte textures into realistic surfaces.

Verdict: It is ray tracing for the masses. If your GPU can run a game from 2015, it can likely run RTGI 0.33 at 60 FPS.