Ray Tracing Renderer

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A physically based ray tracing renderer implemented in C++. This project implements core concepts of ray tracing including reflection, refraction, and global illumination.

Features

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Materials

• Dielectric - Simulates transparent materials like glass with:
  • Fresnel reflectance (Schlick approximation)
  • Total internal reflection
  • Variable refractive indices
• Metal - Reflective materials with:
  • Configurable fuzziness for roughness
  • Energy conservation
• Lambertian - Diffuse materials with:
  • Perfect diffuse reflection
  • Matte surface simulation
• Light - Emissive materials that:
  • Act as light sources
  • Support different colors

Geometry

• Sphere - Perfect spherical objects with:
  • Accurate normal calculation
  • Ray-sphere intersection
• Cube - Box-shaped objects supporting:
  • Six-sided geometry
  • Ray-box intersection

Core Features

• Camera System
  • Configurable field of view
  • Adjustable aspect ratio
  • Look-at functionality
• Global Illumination
  • Monte Carlo path tracing
  • Soft shadows
  • Color bleeding
• Anti-aliasing
  • Multi-sample anti-aliasing
  • Configurable sample count
• Sky System
  • Pluggable sky backgrounds
  • Basic sky gradient
  • Black sky for indoor scenes

Example

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A scene featuring glass sphere, metal cube, and various light sources

A scene featuring metal sphere, glass cube, and various light sources

A scene in basic sky, with depth of fields effect

Technical Details

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Rendering Pipeline

1. Ray Generation
2. Scene Intersection
3. Material Evaluation
4. Light Transport
5. Tone Mapping

Performance Features

• Early ray termination
• Russian roulette path termination
• Progress monitoring
• Exposure control

Usage

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// Create materials
material *glass = new dielectric(1.5);
material *metal = new metal(vec3(0.8, 0.8, 0.8), 0.5);

// Set up scene
object *list[2];
list[0] = new sphere(vec3(0, 0, 0), 0.5, glass);
list[1] = new cube(vec3(-1, -1, -1), vec3(1, 1, 1), metal);

// Configure camera
vec3 lookfrom(-2, 2, 1);
vec3 lookat(0, 0, 0);
camera cam(lookfrom, lookat, 60, 16.0/9.0);

// Render
renderer.render(cam, &world, output, height, width, depth, samples, exposure);

Build Instructions

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Prerequisites

• C++ compiler with C++11 support
• Basic math library
• Image processing tools for output conversion

Compilation

g++ render.cpp -o raytracer -O3 -std=c++11

Running

./raytracer
convert out.ppm out.png  # Convert to PNG format

Implementation Details

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Ray-Object Intersection

• Analytical solution for spheres
• AABB intersection for cubes
• Surface normal computation

Material System

• BRDF implementation
• Fresnel equations
• Microfacet theory basics

Monte Carlo Integration

• Importance sampling
• Path tracing
• Random number generation

Future Improvements

• Texture mapping support
• More primitive shapes
• Parallel rendering
• Motion blur
• Depth of field
• Volumetric rendering

Contributing

Feel free to open issues or submit pull requests for:

• Bug fixes
• Performance improvements
• New features
• Documentation improvements

License

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