Minecraft RTX Mod for Fabric 1.20.4

A comprehensive ray tracing mod for Minecraft that provides hardware-accelerated RTX features using modern OpenGL and compute shaders.

Features

✨ Ray Tracing

• Hardware-accelerated ray tracing with support for NVIDIA RTX, AMD RDNA2+, and Intel Arc GPUs
• Real-time global illumination with configurable bounce lighting
• Ray-traced reflections with multiple quality settings
• Ray-traced shadows with soft shadow sampling
• Ambient occlusion with screen-space and ray-traced methods

🎮 Performance

• Temporal upsampling for improved performance
• AI-based denoising to reduce ray tracing noise
• Dynamic render scaling (50%-200%)
• DLSS-like upscaling using compute shaders
• Adaptive quality based on GPU capabilities

🎨 Visual Enhancements

• HDR rendering with tone mapping
• PBR material system (roughness, metallic, emission)
• Motion vectors for temporal effects
• G-buffer rendering with multiple render targets

⚙️ Configuration

• In-game settings via ModMenu integration
• Real-time shader reloading for development
• Debug visualization modes
• Hardware capability detection

Controls

• R: Toggle RTX on/off
• F5: Reload RTX shaders (for development)

System Requirements

Minimum (Software Ray Tracing)

• Java 17+
• OpenGL 4.6 compatible GPU
• 8GB RAM
• Fabric 1.20.4

Recommended (Hardware Ray Tracing)

• NVIDIA: RTX 20/30/40 series, GTX 1660/1070/1080
• AMD: RX 6000/7000 series (RDNA2/RDNA3)
• Intel: Arc A-series (DG2)
• 16GB RAM
• Fabric 1.20.4

Installation

1. Install Fabric Loader for Minecraft 1.20.4
2. Download and install Fabric API
3. Optional: Install ModMenu for in-game configuration
4. Place the RTX Mod JAR file in your .minecraft/mods folder

Technical Implementation

Architecture

RTXRenderer
├── RTXCapabilities - GPU detection & feature checking
├── RTXShaderManager - Shader compilation & management  
├── RayTracingPipeline - Main ray tracing compute shaders
├── PostProcessingPipeline - Denoising, temporal accumulation, tone mapping
├── SceneManager - World data organization for ray tracing
└── RTXFrameBuffer - Multi-target HDR framebuffers

Rendering Pipeline

1. G-Buffer Generation: Traditional rasterization for primary visibility
2. Ray Tracing Pass: Compute shader for lighting, reflections, and GI
3. Temporal Accumulation: Progressive refinement across frames
4. Denoising: AI-based noise reduction using G-buffer data
5. Tone Mapping: HDR to LDR conversion with exposure control
6. Upscaling: Optional AI upscaling for performance

Shaders

• G-Buffer: gbuffer.vert, gbuffer.frag - Primary visibility
• Ray Tracing: raytracing.comp - Main ray tracing compute shader
• Temporal: temporal_accumulation.comp - Frame accumulation
• Denoising: denoising.comp - AI-based denoising
• Tone Mapping: tonemap.vert, tonemap.frag - HDR processing
• Upscaling: upscaling.comp - AI upscaling

Building from Source

# Clone the repository
git clone <repository-url>
cd minecraft-rtx-fabric-mod

# Build the mod
gradlew build

# The compiled JAR will be in build/libs/

Configuration

The mod creates a configuration file at .minecraft/config/rtx-mod.json with these options:

{
  "rayTracing": {
    "enabled": false,
    "maxBounces": 3,
    "samplesPerPixel": 4,
    "distance": 128.0
  },
  "globalIllumination": {
    "enabled": true,
    "strength": 1.0,
    "samples": 16
  },
  "reflections": {
    "enabled": true,
    "strength": 1.0,
    "quality": 1
  },
  "performance": {
    "renderScale": 100,
    "temporalUpsampling": true,
    "denoising": true
  }
}

Development

This mod uses:

• Fabric API for Minecraft integration
• Mixin for hooking into the render pipeline
• LWJGL 3.3.3 for OpenGL access
• JOML for math operations
• ModMenu for configuration GUI

Key Classes

• RTXRenderer: Main rendering coordinator
• RTXCapabilities: Hardware detection
• RTXShaderManager: Shader compilation and management
• RayTracingPipeline: Core ray tracing implementation
• PostProcessingPipeline: Post-processing effects

Mixins

• GameRendererMixin: Key binding handling
• WorldRendererMixin: Main render loop integration
• RenderSystemMixin: Window resize handling

License

This project is licensed under the MIT License. See LICENSE file for details.

Contributing

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

Troubleshooting

Common Issues

"RTX not supported": Your GPU doesn't support hardware ray tracing. The mod will fall back to software ray tracing with limited functionality.

Low FPS: Try reducing render scale, samples per pixel, or max ray bounces in the configuration.

Shader compilation errors: Make sure you have updated GPU drivers and OpenGL 4.6 support.

Debug Mode

Enable debug mode in the configuration to see:

• RTX capability detection results
• Shader compilation logs
• Performance metrics
• Hardware information

Acknowledgments

• Minecraft Fabric development team
• LWJGL for OpenGL bindings
• JOML for math utilities
• Ray tracing algorithm research and implementations