# 🚀 Raytracer Project Roadmap

This roadmap breaks down the essential steps to build your CPU-based raytracer from scratch in C++.

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## Phase 1: Foundations & Core Engine
- [ ] Set up vector math utilities (`vec3`): add, subtract, dot, cross, normalize  
- [ ] Implement Ray class — origin, direction, basic functions  
- [ ] Basic Sphere object — position, radius, material properties  
- [ ] Ray-Sphere intersection logic — the core of your renderer  
- [ ] Camera setup — generate rays through the viewport  
- [ ] Scene structure — manage objects and lights  

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## Phase 2: Lighting & Shading Basics
- [ ] Diffuse shading (Lambertian reflection) — basic light bounce for realism  
- [ ] Implement simple light sources: directional, point lights  
- [ ] Shadow rays — cast rays toward lights to check occlusion  
- [ ] Basic materials — color, albedo, reflectivity factor  

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## Phase 3: Reflection & Recursion
- [ ] Reflection rays — mirror-like reflections with recursion depth limit  
- [ ] (Optional) Refraction — transparent materials like glass  
- [ ] Recursive ray tracing — combine reflections & lighting  

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## Phase 4: Image Output & Performance
- [ ] Render to PPM file (or PNG with `stb_image_write`)  
- [ ] Anti-aliasing — supersampling for smooth edges  
- [ ] Multi-threading (OpenMP or `std::thread`) for parallel speedup  
- [ ] Optimize math operations — use inline functions, `constexpr` where possible  

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## Phase 5: Scene & Object Expansion
- [ ] Add more shapes: planes, triangles (for meshes)  
- [ ] OBJ file loader — import 3D models  
- [ ] Material system — metals, dielectrics, diffuse, emissive lights  
- [ ] Texture mapping (UV mapping) — add realistic surface detail  
- [ ] Multiple light sources with falloff  

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## Phase 6: Advanced Features (Flex Mode ON)
- [ ] Global Illumination / Path Tracing (big brain mode)  
- [ ] Depth of field camera effect  
- [ ] Motion blur  
- [ ] HDR environment maps for reflections and lighting  
- [ ] GUI or real-time preview (super ambitious)  

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