A fluid music visualizer: ferrofluid, water, lava, honey, jelly and slime.

Fluid is a style of liquids, new in LIQUIDWAVE 1.1: black ferrofluid on white paper, a body of blue water, a lava lamp, honey running off a ledge, a jelly on a table and a lump of neon slime. The music moves each one: the low end swells it, the beat pushes it, and the drums throw, drip or flick pieces of it.

How the liquids are made

All but Water share one engine. A liquid is a set of balls joined by a smooth union, and the width of that union is how far apart two parts still hold on to each other. Push a piece far enough and it pinches off as a drop. Bring it back and it runs into the rest again. The surface is found by tracing a ray through the balls for every pixel, then lit as a material: black gloss, glowing wax, honey gold where it is thin and amber where it is thick.

Nothing in Fluid steps. Every piece eases out and home, the beat is a smooth swell rather than a snap, and the clocks behind the motion only go forward. As in the Metal style, the sound moves the liquid and never the light. Colors turn over on slow clocks of their own, and only Water's blue follows the music, slowly, with the upper mids.

Every Fluid scene

Ferrofluid. Black magnetic liquid on white paper, moving the way the fluid moves in a dish over a speaker. A heart at the middle swells with the low end and the beat, lobes heave around it, and every drum hit throws an arm with a bulb on its end that reaches out and comes home over about a second and a half. A hard hit lets the bulb go as a drop that hangs and runs back in.

Water. A blue liquid surface filling the frame, seen flat-on. Broad, soft folds roll through a body the light passes into, and only the grazing flanks mirror the bright room. Bass deepens the folds and raises a long traveling swell, each kick and snare sends a small dent and swell through the surface, and the upper mids turn it from blue toward teal.

Lava. A lava lamp seen close through its glass: glossy wax in a colored liquid, lit by a bulb below. Blobs swell out of the pool, rise, stretch, run together and cling to the cooled wax at the top before sinking back. The low end swells the wax, and every drum hit pushes a lump of wax up out of the pool on a neck. Its colors turn over: orange wax in violet, red in amber, pink in blue, blue in violet, lime in teal.

Honey. Honey runs off a ledge at the top of the frame, lit from behind against warm cream. A bead gathers at the lip and sinks on a thread that thins as it lengthens. The thread lets go, the drop falls away, and the thread springs back up. The beat bobs the hanging beads, and every drum hit drips a bead of its own.

Jelly. A mound of clear jelly on a pale table. It squats on the beat and springs back. Every drum hit rings through it, its sides wobbling at pitches of their own, and flicks a bead into the air that falls back in. Its flavor turns over slowly: raspberry, orange, lime, soda, grape.

Slime. A heavy lump of glowing neon slime in a dark room. Goo slides down both sides and wells back up through the middle, so it sags, and a drop gathers under it, hangs on a thread and falls. Every drum hit pulls a glob up out of its top on a sticky string and lets it fall back in, and the slime squats where it lands. Air bubbles ride inside it, and it turns slowly between green and aqua.

Click the picture, and Ferrofluid reaches for the spot like a magnet, Lava raises a bud of wax to it, Honey draws a thread down to it, Jelly leans toward it and rings, Slime pulls a glob out to it on a string, and Water sends a wave from it.

How Fluid plays with different music

Drum hits show most: each kick and snare gets its own arm, bud, drip, bead or glob, timed from the hit, so a steady four-on-the-floor keeps the ferrofluid reaching and the honey dripping in time. Bass-heavy music swells the bodies, and a louder passage runs the lamp, the honey and the slime faster.

What to expect

Drops follow drums. Music without kicks or snares, a piano or an ambient pad, swells the liquids but throws little. In silence each keeps an idle of its own: the lamp rises and sinks, the honey drips, the slime flows, the jelly breathes. Water calms to a crawl.

They take more drawing. A ray per pixel costs more than a flat pattern. On a large display, Render quality in Settings → Visual caps the pixels LIQUIDWAVE draws.

Where to go next

Spectral, the other new style in 1.1, draws the music pitch by pitch. LIQUIDWAVE for Mac is a free download with two scenes, Wave and one you pick, and one purchase inside the app unlocks the rest of the 60+ scenes, every liquid included.