Dots Wave

How this effect works

Every loader with dots is secretly the same machine: one wave, sampled at N points. Dot i reads the wave at sin(t × speed − i × offset) — the offset between neighbours is what makes the wave appear to travel from left to right rather than all dots hopping together. We clamp the sine's negative half to zero so each dot rests on the floor between hops; a dot that also dips below the line reads as bouncing on a trampoline, not waiting.

The other two layers re-read the same wave: swell maps it to scale, so a dot is biggest exactly at the top of its hop (things closer to you look bigger — cheap depth), and shade maps it to brightness, so attention follows the crest. This is the same "one wave, several readings" idea as Wavy Text — loaders are just the smallest possible stage for it.