Halftone Waves

How this effect works

Under the hood there's an invisible wave field — a number for every point that rises and falls with sin(x, y, time). On its own you'd draw it as a smooth gradient (flip the dots layer off to see exactly that). The halftone trick is to sample that field on a grid and, at each grid point, draw a dot whose radius is the field's value there. Where the wave is high the dots are fat; where it's low they shrink to nothing — the same way a printed newspaper fakes shades of gray with nothing but black dots of different sizes.

The cell size is the grid spacing (smaller = finer, more dots), dot scale caps how big a dot can get relative to its cell, and speed scales time. The ripple layer adds a second wave that rings out from the center, and where it meets the first they add up — so the dots pulse in interference patterns nobody drew by hand.