Undertone hides the notch and the screen's borders in black, and fills the rest with beautiful generated backgrounds: gradients and shapes that follow your light or dark theme and change on a schedule.
A black strip as tall as the menu bar swallows the notch, so the menu bar reads as bezel and the screen starts below it. Rounded corners put black behind every window tiled into a corner, so the picture never peeks out round an app's own rounded corner.
While the Mac is locked, your picture drifts: the curtains sway, the waves roll, the glows wander. Unlock, and it slows to a stop on your desktop.
Glows, marbling, layered waves, lit spheres, rings, dunes, topographic lines, silk, aurora, a bauhaus grid and a lava lamp. Every picture is generated: each tile below is shuffling, its style kept, its tonality and layout new every time. Lock a style, or let every shuffle pick.
Each tonality has a dark half and a light half. Switch appearance and the picture switches with it: the same shapes, the other colours. Keep a tonality, shuffle them, or let the season choose: cold blues in winter, greens in spring, warm colours in summer, ambers in autumn.
Dither, halftone, reeded glass, bloom, a light leak, paper and posterize, over any style in any tonality. Turn on as many as you like, each with its own settings, or let every shuffle add one at random.
Shuffle by hand, from a hotkey, or let Undertone pick a new picture every hour, every three hours or every day, and on login and wake. Style and tonality are separate choices: keep either, and only the other one changes, and either can leave some out.
undertone shuffleFor a hotkey, a Shortcut or a script.Every space gets its own picture from its own seed, in the same style and colours, so spaces are siblings and you can tell them apart. Or show the same one everywhere.
A fine grain takes the plastic sheen off a gradient and hides banding. A centred title, off until
you want it, tells machines apart in a screen share: {computer}, {user},
{os} and {host} are filled in.
Every style and tonality is drawn in the settings, in the colours you have now: click to keep one or to leave it out of shuffles. Each effect shows itself over your picture, with its own sliders, and a preview of the whole thing sits on top. A few quick toggles live in the menu bar.
undertone shuffle for a hotkey.undertone render draws any picture to a file, without the app.
No. Setting the desktop picture needs none, and Undertone asks for nothing else.
Yes. When the system switches between light and dark, including on a schedule, Undertone redraws the same picture from the other half of its tonality.
A picture is drawn once, in about half a second, when you shuffle or change a setting, and reused after that. The checks compare a file name. With lock screen motion on, each new picture is also drawn as a movie, a few minutes in the background on two cores; playing it is the Mac's video hardware.
Yes: they are a plain ~/.config/undertone/config.toml, read again whenever it changes and
written when you change something in Settings. The file.
Apple Silicon Macs on macOS 15 or later.
Yes, and open source under the MIT licence.