Murmuration

Watch Murmuration live in the browser

A dusk sky runs from amber at the horizon through rose to indigo, with a sun just below the horizon, thin lit clouds and two ridges of dark hills. Across it a flock of starlings twists and folds, leaving faint motion trails and darkening the sky where it bunches up.

The flock follows Craig Reynolds' boids model from 1987: each of 192 simulated birds steers by three local rules, keeping its distance from close neighbours, matching their heading and drifting toward their centre, while a slowly wandering roost point holds the flock together. Each simulated bird is drawn with a few followers, so several hundred silhouettes cross the sky. When the music stops, the birds hang still in the air.

What it reacts to

• Loudness: sets the flock's speed; silence freezes it
• Mids: tighten the alignment, so the flock rolls in waves
• Treble: stirs gusts of turbulence into the flock
• Kick drum: a falcon dives through at a fresh spot and the birds burst away from it before regrouping
• Bass: the low sun glows larger and kicks scatter the flock harder

Tune

Flock speed scales how fast the birds fly, Startle sets how violently they scatter from the falcon, Trails sets how long their motion trails last, and Sky tints the rose band of the dusk.

Music that suits it

Music with clear kicks and lively mids, such as melodic house or breakbeat, keeps the flock rolling and regularly broken apart by the falcon.

How to play it

Install Deus, play music on Spotify, YouTube Music, Yandex Music or any other tab and click the Deus icon on that tab. Then pick Murmuration in the WebGL presets, or press ← → on the page until it comes up.