How to move

Drag
Orbit the camera around the hole. Touch works too.
← → ↑ ↓
Steer the camera without a pointer.
Wheel · pinch · + −
Move nearer to or farther from the hole.
Hold Space or the ring
A ring fills as star trails accelerate outward. Release, or let it fill, to cross into the next world.
Tap the ring
On a phone a single tap crosses at once.
P
Pause or resume the moving parts. Your camera stays under control.
Esc
Cancel a charge, or close this panel.

Switching tabs, losing focus or a cancelled touch never triggers a crossing. If your system asks for reduced motion, the scene starts paused and crossings are a plain cross-fade.