🌌 miniRT 🌌

A stunning real-time raytracer built from scratch!

Simple vaporwave scene rendered using miniRT

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🖼️ Gallery

Some of the cool stuff you can do in miniRT

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🌍 Create Your World

Write your own .rt scene files to populate your world with:

• Custom shapes, textures, and bump maps.
• Dynamic lighting and shadows.
• Ambient Global Colour

Example .rt file:

C 0,0,-10 0,1,0 90
sp 0,0,0 1.0 255,0,0
L 5,10,-5 1.0 255,255,255
A 0 0,0,0

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✅ Prerequisites:

• Make
• X11, OpenGL (Linux)
• OpenGL, Appkit (MacOS)
• WSL (To run on Windows as a Linux container. Linux prerequisites apply).

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🚀 Getting Started

1. Clone the repository:

   git clone https://github.com/Pastifier/miniRT.git
   cd miniRT

2. Build the project:

   make

3. Run the raytracer:

   ./miniRT <scene_name.rt>

   Replace <scene_name.rt> with the name of your .rt scene file. Explore pre-made scenes or create your own for limitless creativity!

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✨ Features

🖼️ Ray Tracing

• Handles intersections with multiple shapes:
  • Spheres, planes, cylinders, cones, and cubes.
• Full support for:
  • Ambient, diffuse, and specular lighting.
  • Reflections/Refractions
  • Shadows and customizable spotlights with light falloff.

🎥 Interactive Camera and Translatable-Objects

• Camera Mode:
  • Real-time camera movement with smooth rotations and translations.
  • Camera-controls:
    • WASD: move around.
    • Space/Shift: Elevate/Descend (respectively).
    • Arrow-keys: Rotate
    • ESC in Camera-Mode exits the program.
• Select Mode:
  • Left-click objects to select them.
  • Object-controls:
    • R: toggle reflections/refractions.
    • WASD: move around.
    • Space/Shift: Elevate/Descend.
    • ESC in Select-Mode goes back to Camera-Mode.

🎨 Textures and Bump Mapping

• Bump mapping for intricate surface detail using normal maps on spheres and planes.
• Support for XPM textures to bring your scenes to life.

💡 Spotlights

• Customizable cone angles based on the spotlight's spot angle for realistic light falloff.

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📈 Performance Optimizations

• Multithreading: Efficient thread distribution for high-speed rendering.
• LERP'ing:
  • Skip pixels and compare the colours of the surrounding pixels.
  • If the difference is below a certain threshold, interpolate the colours, otherwise, shoot the rays.
• Our Very Own SIMD Linear Algebra Library:
  • Optimized 4x4 matrix operations for raytracing.
  • Features the lag_mat4s_get_transform_inverse() function for lightning-fast decomposed matrix inversions.
  • Innovative yet highly efficient mathematical design.

🔍 Benchmarks

• Simple scenes: ~(12-36)ms per frame (~25-83 Frames Per Second).
• Complex scenes with multiple normal map textures: Under 200ms per frame (~5-10 Frames Per Second).

Benchmarked on typical scenes including multiple objects and light sources.

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🔧 Technical Details

• Rotations:
  • Quaternion extraction for seamless orientation.
  • Axis rotation using Rodrigues' formula.
• Deltatime integration for fluid motion.
• Custom Parsing:
  • Read .rt scene files to define objects, lights, and camera configurations.
• Thread Pool:
  • Reuses threads for every frame to minimize initialization overhead.
• Math Library: LagAMat
  • Used efficient memory manipulations and mathematical tricks, made available by the use of unions.
  • Broke down matrices into scale and translation vectors, and rotational component, to cut the cost of calculating a general matrix inverse as it's not needed.

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🎯 What Makes our miniRT Unique?

• Advanced yet approachable real-time rendering capabilities.
• A dedicated linear algebra library optimized for simplicity and performance.
• Innovative, efficient mathematical solutions built exclusively for this project.
• A perfect blend of creativity and technical rigor to make ray tracing interactive.

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📜 Acknowledgments

• This project is part of the 42 School curriculum, using the homebrewed MiniLibX Graphics Library to blend mathematical elegance and computational performance to bring scenes to life.
• A huge thanks to our fellow 42-students for their support and encouragements, and especially . Which was a huge inspiration, and showed us what this project is capable of!
• The Ray Tracer Challenge book for its simple, yet highly effective test-driven approach to raytracing.
• Our good friend Emad Aldeen Hammoude, for his cool suggestions on the README file!

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🛠️ How to Contribute

1. Fork the repo.
2. Create a feature branch: git checkout -b my-feature.
3. Commit your changes: git commit -m 'Add cool feature'.
4. Push to the branch: git push origin my-feature.
5. Open a Pull Request!

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💻 Made with ❤️ for ray tracing enthusiasts everywhere.