Torus

Splashery stretches a drumhead over this Splash's outline, twelve inches across, and finds the ways it can ring. Its lowest is 526.9 Hz, 12 cents sharp of C5. The next fifteen are its overtones, and each one draws its own figure: sand gathers on the lines that stay still.

Tap it to spin it on its edge. Dress it as a donut, bagel or swim ring in the Splash tab.

A torus is the shape of a ring: a circle swept around a line beside it, like a hoop made of tube. Donuts, bagels, swim rings and bicycle inner tubes are all tori. In topology, the math of shapes that can stretch but not tear, a torus has exactly one hole, so a coffee mug with its handle counts as one too.

Tap it and it pops up onto its edge and wobbles around like a coin spun on a table, leaning lower and circling faster until it drops flat. Real rings and coins do this: as one leans lower, its low point runs around faster, so a settling coin whirs quicker just before it stops. Under Dress it as in the Splash tab, pick a plain torus, a donut, a bagel or a swim ring.

Made in Splashery. Its code is MIT.

This link opens it in the Playground. To put it on your own page, add the element and one script tag. Every option.