CPP-Renderer/ROADMAP.md

🚀 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

Objectives:

• Render a single sphere with basic color
• Output to a simple PPM file format

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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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