A Monte Carlo path tracer written in C23 with physically-based rendering.

make                    # release: -O3 -flto -march=native
make debug              # debug: -g3 -O0 -fsanitize
./rt scenes/figuras_pov.rt

• Path tracing — 5 bounce Monte Carlo integration
• 4 base geometries — sphere, plane, cylinder, cone
• Cube — decomposed into 6 bounded faces
• Materials — diffuse, metallic (GGX), mirror, glass (Fresnel), emissive, checkerboard
• Textures — PNG texture mapping with UV coordinates
• Bump mapping — normal perturbation from height maps
• Depth of field — thin-lens camera with configurable aperture & focus distance
• Lighting — ambient + multiple point lights + emissive area lights
• Shadows — shadow rays with occlusion testing
• Specular highlights — Phong model per material
• BVH — bounding volume hierarchy acceleration
• Multi-threading — 6-thread pthread pool
• Progressive rendering — sample accumulation over time
• Interactive console — live edit camera, lights, objects, materials
• Scene files — .rt format with material suffixes

./rt scenes/subject_1.rt      # 4 base objects + 2 lights
./rt scenes/subject_2.rt      # Same scene, rotated camera
./rt scenes/subject_3.rt      # Shadow mixing demo
./rt scenes/03_glass_galore.rt # Glass + Fresnel
./rt scenes/11_depth_of_field.rt # DOF demo