For the complete documentation index, see llms.txt. Markdown variants are available by appending .md to any URL or sending an Accept: text/markdown header. The asciicn agent skill, for building any ASCII effect on the engine, is at /.well-known/agent-skills/asciicn/SKILL.md.

Satin

Deep magenta satin: a few wide folds that turn slowly and catch the light along their edges, in ANSI shade blocks.

Controls
Seed
Charset
Colour mode
Intensity1
Cell12px
Animate

Installation

pnpm dlx shadcn@latest add https://asciicn.dev/r/satin.json

Usage

import { Satin } from "@/components/asciicn/satin";
 
export function Hero() {
  return (
    <section className="relative isolate min-h-[480px]">
      <Satin seed="orchid" className="absolute inset-0 -z-10" />
      <h1>Your headline</h1>
    </section>
  );
}

Each seed rolls a set of ribbons: how many, how they swing, how much slow noise bends them, how wide they are and how often they twist. A ribbon's width follows its twist, so where it turns edge-on it narrows to a bright line, like a strip of film turning in the light. Its rims are the brightest part, a soft halo surrounds it, and the ribbons further back sit a little dimmer. In truecolor each ribbon takes its own hue along the palette.

Satin stays in deep magenta and leans slightly towards purple. It rolls three or four wide ribbons with gentle folds and slow twists. It draws in blocks by default ( â–‘â–’â–“â–ˆ), which gives the folds a woven, soft finish.

Each seed gets its own palette, built in OKLCH: a first hue, then a turn of up to 120 degrees that never runs through the olive and khaki hues that turn muddy at glyph sizes. The palette comes in two versions, deep to bright on dark paper and pale to deep on light paper, and switches with the theme, so the densest glyphs always have the most contrast.

The parts are in lib/ascii/seed.ts (shipped with the ascii-shader item) if you want your own preset: seedParams(seed, kind, options) rolls the parameters, seedField(seed, kind) returns { field, colorField, uniforms } for AsciiShader, and the SeedField component wraps both.

Examples

Behind a call to action

A lower intensity behind a heading and a button.

Three seeds

Three seed strings, three drapes of the same satin.

Props

PropTypeDefault
seed

Any string. The same seed always draws the same field; each new one rolls a different shape, palette and motion in the same family.

Type: stringDefault "satin"
intensity

Scales the exposure the seed settled on, from 0 to 1.5. Lower it to put text on top.

Type: numberDefault 1
ink

The glyph colour in mono mode.

Type: AsciiColorDefault "--ascii-ink"
paper

The surface behind the glyphs.

Type: AsciiColorDefault "--ascii-paper"
palette

Colours for palette mode, paper first.

Type: [AsciiColor, AsciiColor, ...AsciiColor[]]Default Paper, then the seed's four colours
charset

Which glyphs draw the tones. See Charsets.

Type: CharsetNameDefault "blocks"
chars

A custom ramp from empty to dense, such as " .oO@". Wins over charset.

Type: stringDefault –
colorMode

How glyphs are coloured. truecolor uses the seed's own OKLCH palette; palette maps tone to it; mono, duotone and ansi16 work as everywhere else.

Type: "mono" | "truecolor" | "ansi16" | "duotone" | "palette"Default "truecolor"
phosphor

In mono mode, a CRT ink and glass that replace ink and paper.

Type: "p1" | "p3" | "ibm" | "blueprint"Default –
ramp

In duotone mode, the colour ramp from dark to light.

Type: RampName | string[]Default –
ansi

In ansi16 mode, which 16-colour table.

Type: "vga" | "xterm"Default "vga"
grade

Brightness, contrast, gamma and saturation applied to tones before glyphs are picked.

Type: GradeDefault –
invert

Dense glyphs for dark tones instead of bright ones.

Type: booleanDefault false
threshold

Braille and quadrants: the tone that lights a dot.

Type: numberDefault 0.5
edgeThreshold

Edge charset: how strong a change in tone must be to draw - / | or \.

Type: numberDefault 0.22
dither

Ordered dithering between neighbouring glyph levels.

Type: "none" | "bayer2" | "bayer4" | "bayer8" | "blue-noise"Default "none"
background

"transparent" draws the glyphs only, over your own surface.

Type: "paper" | "transparent"Default "paper"
fx

CRT finish: scanlines, bloom, curvature, glitch, flicker and vignette, each 0 to 1.

Type: PostFxDefault –
interaction

What the pointer does to the glyphs. Off by default, so the field ignores hover; opt in only where a pointer effect suits the page.

Type: "none" | "repel" | "ripple" | "trail"Default "none"
interactive

false turns pointer interaction off whatever interaction says.

Type: booleanDefault true
cell

Height of one glyph cell in CSS pixels.

Type: numberDefault 12
speed

How fast it moves.

Type: numberDefault 1
animate

false stops the motion: a still frame if it starts off, the current frame if it was moving.

Type: booleanDefault true
fps

Frame rate cap.

Type: numberDefault 30
stillTime

The moment drawn when motion is off or reduced, in seconds.

Type: numberDefault 8
handle

Filled with a handle that reads back the current frame, for export to text, ANSI, SVG or PNG.

Type: RefObject<AsciiHandle | null>Default –
className

Size and position. The background fills this box.

Type: stringDefault –

Notes

  • It is decorative and hidden from assistive technology. Put real text on top of it, not inside it.
  • With reduced motion turned on, it draws one still frame at stillTime and stops.
  • By default it does not react to the pointer: moving the mouse over it changes nothing.
  • It pauses when scrolled out of view or when the tab is hidden, and releases its WebGL context when far offscreen. Without WebGL it shows soft CSS glows in the seed's colours.
  • A seed is rolled once, on the CPU, in a few milliseconds: a small exposure check samples the field at 40×22 at three moments and re-rolls (up to eight times) until between a quarter and three fifths of the box carries a glyph, then sets the gain so the brightest glyphs reach the top of the ramp. Changing seed re-rolls; changing the look props does not. See Performance.