Bend light through gravity wells and turn it into art.
Geodesic lets you drop masses onto a canvas and watch thousands of light rays warp around them in real time. The patterns that emerge — caustics, interference, lensing arcs — look like something out of a telescope, but you made them by clicking.
It's a toy, an art tool, and a physics playground rolled into one. Every frame is exportable as a PNG.
- Real-time ray tracing — 1000+ rays bent through curved spacetime, computed in Rust/WASM
- 3D spacetime mesh — Optional wireframe showing how mass curves the fabric of space
- 5 color schemes — Infrared, Ocean, Aurora, Mono, Plasma
- Smart shuffle — Generates aesthetically composed scenes with one click
- Particle trajectories — Launch test particles and watch them orbit, spiral, or get captured
- Time dilation overlay — See where time slows down near massive objects
- Art Shot export — One-click export from the optimal camera angle
- Gallery presets — Curated starting points: black holes, binary systems, gravitational lenses
- Auto-rotation — Scene slowly orbits when idle, screensaver style
- Undo — Ctrl+Z works like you'd expect
| Action | What it does |
|---|---|
| Click | Drop a new mass |
| Drag | Move a mass around |
| Scroll on a mass | Make it heavier / lighter |
| Right-click a mass | Delete it |
| Long press (mobile) | Delete |
| R | Shuffle — new random scene |
| Ctrl+Z | Undo |
| E | Export PNG |
| F | Fullscreen |
| M | Toggle spacetime mesh |
| T | Toggle time dilation |
| G | Open gallery |
| P | Switch mass/particle mode |
| Space | Pause/resume |
| Physics | Rust → WASM via wasm-bindgen. RK4 integrator with GR correction: a = -M/r² · (1 + 3Mv²/r²) |
| Rendering | React Three Fiber + Three.js. Single draw call, additive blending, per-vertex curvature coloring |
| Post-processing | Bloom + vignette + chromatic aberration |
| Mesh deformation | GPU-side vertex shader, 40k vertices displaced in real time |
| Frontend | Next.js 16, TypeScript, Tailwind CSS |
The WASM binary is ~16KB gzipped. It traces 1000 rays × 2000 steps in about 5ms on a modern machine.
git clone https://github.com/omerarslan0/geodesic.git
cd geodesic
npm install
npm run devWASM is pre-built in public/wasm/. If you want to recompile the Rust physics engine:
# needs rust + wasm-pack
npm run build:wasmEach ray is a null geodesic traced through a Schwarzschild-like field. Multiple masses are superimposed — not physically rigorous for multi-body GR, but it produces gorgeous caustic patterns, which is the whole point.
The particle sim uses velocity Verlet integration with the same GR-corrected acceleration. ISCO (innermost stable circular orbit) is shown at r = 3M for each mass.
MIT