gentoo

[github]

the lavender g, scanned now and then

distros 54×28 30 fps in colour or one ink 6.7 kB

use it

html

<script type="module" src="https://ascii.rest/ascii.js"></script>

<ascii-art piece="gentoo" options='{"scan":5}'></ascii-art>

No install and no build step. ascii.js defines the <ascii-art> tag, loads the piece from ascii.rest, plays it while it is on screen, and holds the first frame for anyone who prefers reduced motion. Add mono, <ascii-art piece="gentoo" mono>, for one ink.

react

// npm install github:bas3line/ascii
import { Ascii } from "ascii.rest/react";
import { gentoo } from "ascii.rest/pieces";

<Ascii piece={gentoo} options={{"scan":5}} />

A client component, so it works in the Next.js app router as it is. Pass the name instead, piece="gentoo", to fetch the piece only when it mounts. Add mono for one ink.

astro

---
// npm install github:bas3line/ascii
import Ascii from "ascii.rest/astro";
---

<Ascii piece="gentoo" options={{"scan":5}} />

Renders the first frame on the server, so the page is whole before any script runs, then plays the piece once it loads. Add mono for one ink.

typescript

// npm install github:bas3line/ascii
import { mount } from "ascii.rest";
import { gentoo } from "ascii.rest/pieces";

const el = document.querySelector<HTMLCanvasElement>("canvas")!;
const stop = mount(el, gentoo, {"scan":5});

mount plays a piece in a <pre>, or on a <canvas> for the coloured ones, and returns a function that stops it. Every piece, option and frame is typed. Mount it in a <pre> for one ink.

gentoo.ts

[js] [github] 
/*
 * gentoo: the Gentoo logo, a lavender g like a bent stone, with a scan line
 * running down it every few seconds that scrambles what it passes.
 *
 * Drawn from devicon's gentoo-plain.svg (MIT): each cell holds the character
 * whose shape best matches the logo's edge through it, and 8 where the logo is
 * solid. On a canvas it takes the logo's colours, lifted on a dark page where
 * they would sink into it; in a <pre> it is one ink, from the same drawing.
 * The logo is a trademark of its owner, shown here to name the distribution.
 */
import type { Frame, Meta } from "../types.ts";

export interface GentooOptions {
  [key: string]: unknown;
  /** Seconds between scans; 0 keeps the logo still. */
  scan: number;
}

export const meta = {
  name: "gentoo",
  category: "distros",
  note: "the lavender g, scanned now and then",
  cols: 54,
  rows: 28,
  fps: 30,
  options: { scan: 5 },
  // The logo's colour for a light page, then for a dark one; each as drawn, then twice lighter for the scan.
  palette: [
    "#9d95de", "#bfbaea", "#e2dff5", "#9d95de", "#bfbaea", "#e2dff5",
  ],
} satisfies Meta<GentooOptions>;

// In a <pre>, in the page's own colour.
const MONO = String.raw`

               ..'________''-.,
            .__p88888888888qq_,'~_
         .'_p888888888888888888qq_'\_
       ,_p8888888888888888888888888q_"~_
     .'q888888888888888PYY88888888888q_'"(,
    ,'q88888888888888"       "8888888888q,"\,
   _"q88888888888888P  q888qq, '8888888888q,'\,
   d )88888888888888p  8888888, '88888888888q,'\,
   8q,"88888888888888q_ "'""YP _p8888888888888_ "(
   "88q_ "Y8888888888888qq___pp8888888888888888p '\
    'O88qq_ '"Y888888888888888888888888888888888| 'p
      '"8888qq_  "Y8888888888888888888888888888P' |8
         '"Y8888"_p888888888888888888888888888"  _8P
             '"_p888888888888888888888888888"  _p88"
          .:.p8888888888888888888888888888"  .p88P'
        .'_p888888888888888888888888888P"  .p888"
      .'_p888888888888888888888888888P'  _p888"
    .:.p88888888888888888888888888P"   _p88P"
   .'_8888888888888888888888888P"   _p888P"
  \| 88888888888888888888888P"'  _p8888"
  d. 88888888888888888888P"  ._p8888P"
  8p "888888888888888P"'  _pp8888P"
  )8_  "888888PP""'  __pp88888P"
   Y8q__      .___pp888888P"'
    "88888888888888888P""
      '"888888888P""'

`;

// On a canvas, and the colour of each cell: an index into the logo's colours.
const ART = String.raw`

               ..'________''-.,
            .__p88888888888qq_,'~_
         .'_p888888888888888888qq_'\_
       ,_p8888888888888888888888888q_"~_
     .'q888888888888888PYY88888888888q_'"(,
    ,'q88888888888888"       "8888888888q,"\,
   _"q88888888888888P  q888qq, '8888888888q,'\,
   d )88888888888888p  8888888, '88888888888q,'\,
   8q,"88888888888888q_ "'""YP _p8888888888888_ "(
   "88q_ "Y8888888888888qq___pp8888888888888888p '\
    'O88qq_ '"Y888888888888888888888888888888888| 'p
      '"8888qq_  "Y8888888888888888888888888888P' |8
         '"Y8888"_p888888888888888888888888888"  _8P
             '"_p888888888888888888888888888"  _p88"
          .:.p8888888888888888888888888888"  .p88P'
        .'_p888888888888888888888888888P"  .p888"
      .'_p888888888888888888888888888P'  _p888"
    .:.p88888888888888888888888888P"   _p88P"
   .'_8888888888888888888888888P"   _p888P"
  \| 88888888888888888888888P"'  _p8888"
  d. 88888888888888888888P"  ._p8888P"
  8p "888888888888888P"'  _pp8888P"
  )8_  "888888PP""'  __pp88888P"
   Y8q__      .___pp888888P"'
    "88888888888888888P""
      '"888888888P""'

`;
const INK = String.raw`

               0000000000000000
            0000000000000000000000
         0000000000000000000000000000
       000000000000000000000000000000000
     00000000000000000000000000000000000000
    000000000000000000       0000000000000000
   000000000000000000  0000000 0000000000000000
   0 0000000000000000  00000000 00000000000000000
   00000000000000000000 000000 0000000000000000 00
   00000 000000000000000000000000000000000000000 00
    0000000 0000000000000000000000000000000000000 00
      000000000  00000000000000000000000000000000 00
         00000000000000000000000000000000000000  000
             00000000000000000000000000000000  00000
          000000000000000000000000000000000  000000
        000000000000000000000000000000000  000000
      000000000000000000000000000000000  000000
    00000000000000000000000000000000   000000
   000000000000000000000000000000   0000000
  00 00000000000000000000000000  0000000
  00 0000000000000000000000  000000000
  00 0000000000000000000  000000000
  000  000000000000  00000000000
   00000      000000000000000
    000000000000000000000
      000000000000000

`;

const START = 0.5; // seconds before the first scan
const PASS = 2; // seconds a scan takes, top to bottom
const HEAD = 2; // rows the line scrambles
const TRAIL = 5; // rows of afterglow behind it
const NOISE = "#$%&*+<=>?@[]{}"; // what the line scrambles the logo into

const lines = (art: string) => art.slice(1, -1).split("\n").map((line) => line.padEnd(meta.cols));

function hash(x: number, y: number, k: number) {
  let h = Math.imul(x, 73856093) ^ Math.imul(y, 19349663) ^ Math.imul(k, 83492791);
  h = Math.imul(h ^ (h >>> 13), 1274126177);
  return (h ^ (h >>> 16)) >>> 0;
}

export default function gentoo({ scan = meta.options.scan }: Partial<GentooOptions> = {}): Frame {
  const { cols, rows, fps } = meta;
  const mono = lines(MONO), art = lines(ART), ink = lines(INK);
  const n = meta.palette.length / 6;
  const every = scan > 0 ? Math.max(scan, PASS + 0.5) : 0;
  // The line runs from the logo's first row to past its last, rather than the whole frame.
  let first = rows, last = -1;
  for (const pic of [mono, art])
    pic.forEach((line, y) => {
      if (line.trim()) (first = Math.min(first, y)), (last = Math.max(last, y));
    });
  const span = last - first + 1 + HEAD + TRAIL;

  return (t, { paper = false, color } = {}) => {
    const pic = color ? art : mono;
    const since = t - START;
    const at = every && since >= 0 ? first + (span * (since % every)) / PASS : -Infinity;
    const tick = Math.floor((t * fps) / 2); // the noise changes every other frame
    const out: string[] = [];
    for (let y = 0; y < rows; y++) {
      const d = at - y; // rows since the line reached this one
      const level = d >= 0 && d < HEAD ? 2 : d >= HEAD && d < HEAD + TRAIL ? 1 : 0;
      let line = "";
      for (let x = 0; x < cols; x++) {
        let ch = pic[y][x];
        if (ch !== " ") {
          if (level === 2) {
            const h = hash(x, y, tick);
            if (h % 4) ch = NOISE[(h >>> 2) % NOISE.length];
          }
          if (color) color[y * cols + x] = (paper ? 0 : 3 * n) + level * n + parseInt(ink[y][x], 36);
        }
        line += ch;
      }
      out.push(line);
    }
    return out.join("\n");
  };
}