WASM RaytracerRust → WebAssembly

Three reflective spheres on a checkerboard, ray-traced per pixel — shadows, reflections and all — by a raytracer written in Rust and compiled to wasm32-unknown-unknown. There's no wasm-bindgen here: Rust exposes two functions over a raw linear-memory ABI, JS blits the framebuffer straight out of WebAssembly memory onto the canvas. The whole renderer is 22 KB of wasm.

booting…

Loading WebAssembly…

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Every frame, Rust shoots one ray per pixel from an orbiting camera into the scene, finds the nearest sphere or the ground plane, then adds a diffuse term, a hard shadow ray toward the light, a specular highlight, and up to two reflection bounces. Gamma-corrected colours are packed as RGBA into a Vec<u8> that lives in WebAssembly's linear memory. JavaScript never touches the pixels — it just wraps that memory in a Uint8ClampedArray and calls putImageData. Bump the resolution to feel the cost scale, and watch the FPS.

Rust source (src/lib.rs)

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