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🔮 Raytracer — Rust + WASM

    A real-time ray tracer rendering a 640×480 scene with 5 spheres,
    reflections, shadows, and an orbiting camera —
    all computed per-pixel in Rust, compiled to WASM.
  

How Ray Tracing Works

For each pixel, a ray is cast from the camera through the image plane into the scene. The ray tests intersection against every sphere. At the hit point, we compute lighting (diffuse + specular) from two point lights, check shadows, and recursively trace reflected rays up to 3 bounces deep.

Scene

Object	Color	Specular	Reflective
Ground plane	Gray	10	15%
Azure sphere	Blue	80	40%
Green sphere	Green	200	60%
Red sphere	Red	50	20%
Gold sphere	Yellow	120	50%

Performance

At 640×480 = 307,200 pixels per frame, each requiring sphere intersections, shadow rays, and reflection bounces, this is a lot of math. Rust compiles to tight WASM that typically achieves 3-8 fps depending on device — impressive for a brute-force per-pixel raytracer running in a browser tab.

Implementation Details

Vec3 — minimal vector math (dot, normalize, reflect, scale)
ImageData — pixel buffer written directly to canvas via put_image_data
Clamped<&[u8]> — zero-copy buffer transfer from Rust to Canvas API
Camera orbits the scene using sin/cos of elapsed time

Build

wasm-pack build rust/raytracer --target web --out-dir ../../resources/public/wasm/raytracer