CSG ray tracer

A C++17 ray tracer that renders JSON scenes built with constructive solid geometry. University team project, graded 20/20 with maximum bonus points.

Team of three, TU Hamburg, Object Oriented Programming course

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  Framed mirror with second-order reflections

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  Glass tori, metal and a puddle with an uneven edge

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  Glass of different thickness refracting a striped floor

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  Neon tunnel animation built from CSG frames

What I built

• Everything is a Solid with two methods, intersect(ray) and contains(point). Primitives, boolean operations and transforms all implement it (Composite pattern), so CSG nests without limit and a new primitive only needs those two methods.
• Spheres, half-spaces and tori, including a custom quartic solver for the torus. Union, intersection, difference, exclusion and negation reduce to an algebra of sorted ray intervals.
• Recursive shading: reflection, refraction by Snell’s law with total internal reflection, shadows, Phong lighting, jittered anti-aliasing. Multithreaded rendering cut the showcase scene from 5.3 s to 1.1 s on 12 cores.
• Unit tests for every module check properties rather than magic numbers, e.g. a glass sphere must flip the background upside down. Every JSON scene runs as a regression test in CTest, with AddressSanitizer and UBSan builds.
• Multi-stage Docker build pinned by digest that runs the tests with GCC and -Werror during the build, about 360 MB final image running as a non-root user.
• Python bindings via pybind11 and ffmpeg scripts for animations, Doxygen API docs and UML class diagrams.

Tech stack