A small physics toy that runs in the browser. Balls bounce around inside a spinning shape while you mess with gravity, rotation, colors and sound.
| Default view | Everything Random |
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The panel on the right controls everything. The random button rerolls the shape, cross, colors and background in one click.
- 32 outer shapes (polygons, stars, plus things like a heart, ghost, rocket and skull) and 24 inner cross shapes that spin independently.
- Adjustable gravity strength and direction — you can flip it sideways or upside down.
- An optional gap in the cross that balls can fall through. It can step to the next arm manually or cycle on a timer.
- 14 color themes, 14 ball palettes and 14 background styles, mixed and matched however you like.
- A generative ambient soundtrack plus a short tone on each ball hit, panned by where the ball is.
- Trails, a fog effect, and per-ball spin that you can actually see on the highlight.
- Runs at 60 FPS with a few hundred balls; scales down cleanly on phones.
- UI translated into 8 languages (EN, DE, ES, FR, IT, PT, JA, ZH).
Balls spawn on their own. From there:
- Drag the Gravity and Spin sliders and watch the motion change.
- Pick a shape or cross from the grids, or hit the dice button next to each to randomize just that one.
- Everything Random rerolls the whole scene. ↺ Cycle keeps changing it on its own every few seconds.
- Sliders for ball count, size, speed and randomness are under "Ball Colors".
Your shape, physics and sound settings are saved in localStorage. The color themes reroll on each visit, so it looks a little different every time you open it.
Everything runs in your browser. Settings stay on your device in localStorage — no accounts, no cookies, no personal data collected. The hosted version uses Vercel's cookieless, anonymized page analytics.
- Plain JavaScript, no frameworks.
- HTML5 Canvas 2D for rendering, with cached ball sprites and an offscreen background layer.
- The Web Audio API for the synth and hit sounds.
- Hosted on Vercel.