opensuse

[github]

the green chameleon, scanned now and then

distros 69×18 30 fps in colour or one ink 6.1 kB

use it

html

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

<ascii-art piece="opensuse" 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="opensuse" mono>, for one ink.

react

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

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

A client component, so it works in the Next.js app router as it is. Pass the name instead, piece="opensuse", 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="opensuse" 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 { opensuse } from "ascii.rest/pieces";

const el = document.querySelector<HTMLCanvasElement>("canvas")!;
const stop = mount(el, opensuse, {"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.

opensuse.ts

[js] [github] 
/*
 * opensuse: the openSUSE logo, the green chameleon, with a scan line running
 * down it every few seconds that scrambles what it passes.
 *
 * Drawn from devicon's opensuse-original.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 OpensuseOptions {
  [key: string]: unknown;
  /** Seconds between scans; 0 keeps the logo still. */
  scan: number;
}

export const meta = {
  name: "opensuse",
  category: "distros",
  note: "the green chameleon, scanned now and then",
  cols: 69,
  rows: 18,
  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: [
    "#76be26", "#a6d572", "#d6ecbe", "#76be26", "#a6d572", "#d6ecbe",
  ],
} satisfies Meta<OpensuseOptions>;

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

                    .__pppq888888888888qqqqq___   qqq___,
                _pp888888888888888888888888888888q88888888qqq__
            __p888888888888888888888888888888888888888888P"__"Y8_
         ._p88888888888888888888888888888888888888888888P\8P"Yp"8p
       _p88888888888888888888888888888888888888888888888p/88q8P.88,
     .p888888888888888888888888888888888888888888888("888q_"""_8888
    _888888888888888888888888888888888888888888888888qq_,"Y8888PP"_
   q888888P""""""Y8888888888888888888888888888888888888888qqqpppq8"
  \88888"  __pq__, '"88888888888888888888888888888888888888888P""
  d888P  _88888888q_  "88888888P"""""Y888888888"    '''''''
  8888| |888"''"Y888p   888888'        "888888P
  8888p "888q_q_ "888,   8888P           "88888
  "8888_ "88888P .888|   '"88p             "888q  ,
   "8888q_, ''  _p888'       '                '"Y'|'
    'Y8888888q88888P'
       "Y8888888P"'

`;

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

                    .__pppq888888888888qqqqq___   qqq___,
                _pp888888888888888888888888888888q88888888qqq__
            __p888888888888888888888888888888888888888888P"__"Y8_
         ._p88888888888888888888888888888888888888888888P\8P"Yp"8p
       _p88888888888888888888888888888888888888888888888p/88q8P.88,
     .p888888888888888888888888888888888888888888888("888q_"""_8888
    _888888888888888888888888888888888888888888888888qq_,"Y8888PP"_
   q888888P""""""Y8888888888888888888888888888888888888888qqqpppq8"
  \88888"  __pq__, '"88888888888888888888888888888888888888888P""
  d888P  _88888888q_  "88888888P"""""Y888888888"    '''''''
  8888| |888"''"Y888p   888888'        "888888P
  8888p "888q_q_ "888,   8888P           "88888
  "8888_ "88888P .888|   '"88p             "888q  ,
   "8888q_, ''  _p888'       '                '"Y'|'
    'Y8888888q88888P'
       "Y8888888P"'

`;
const INK = String.raw`

                    000000000000000000000000000   0000000
                00000000000000000000000000000000000000000000000
            00000000000000000000000000000000000000000000000000000
         000000000000000000000000000000000000000000000000000000000
       000000000000000000000000000000000000000000000000000000000000
     00000000000000000000000000000000000000000000000000000000000000
    000000000000000000000000000000000000000000000000000000000000000
   0000000000000000000000000000000000000000000000000000000000000000
  0000000  0000000 0000000000000000000000000000000000000000000000
  00000  00000000000  00000000000000000000000000    0000000
  00000 0000000000000   0000000        00000000
  00000 00000000 00000   00000           000000
  000000 0000000 00000   00000             00000  0
   00000000 00  000000       0                000000
    00000000000000000
       000000000000

`;

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 opensuse({ scan = meta.options.scan }: Partial<OpensuseOptions> = {}): 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");
  };
}