From d9b4652f512df0e319e9e3723340aa0cc8f899b6 Mon Sep 17 00:00:00 2001 From: Dicken Date: Mon, 25 May 2026 15:47:50 +0200 Subject: [PATCH] frontend/generate-icons.mjs aktualisiert --- frontend/generate-icons.mjs | 191 ++++++++++++++++++------------------ 1 file changed, 93 insertions(+), 98 deletions(-) diff --git a/frontend/generate-icons.mjs b/frontend/generate-icons.mjs index f0fa36c..1f178f9 100644 --- a/frontend/generate-icons.mjs +++ b/frontend/generate-icons.mjs @@ -1,106 +1,101 @@ -// Generiert icon-192.png und icon-512.png ohne externe Abhängigkeiten -// Wird automatisch vor dem Build ausgeführt (prebuild script) -import { createWriteStream } from 'fs'; -import { mkdir } from 'fs/promises'; +import { writeFileSync, mkdirSync } from 'fs'; -await mkdir('./public', { recursive: true }); +mkdirSync('./public', { recursive: true }); -function createPNG(size) { - // Minimales PNG: dunkel (#0d0d0f) mit DD in teal (#4ecdc4) - // Wir nutzen den Canvas aus dem Vite/Node Kontext nicht – - // stattdessen schreiben wir ein gültiges einfarbiges PNG per Hand - const width = size, height = size; - - function crc32(buf) { - let c, crcTable = []; - for (let n = 0; n < 256; n++) { - c = n; - for (let k = 0; k < 8; k++) c = (c & 1) ? 0xedb88320 ^ (c >>> 1) : c >>> 1; - crcTable[n] = c; - } - let crc = 0xffffffff; - for (let i = 0; i < buf.length; i++) crc = crcTable[(crc ^ buf[i]) & 0xff] ^ (crc >>> 8); - return (crc ^ 0xffffffff) >>> 0; +function crc32(buf) { + const table = new Uint32Array(256); + for (let n = 0; n < 256; n++) { + let c = n; + for (let k = 0; k < 8; k++) c = (c & 1) ? (0xedb88320 ^ (c >>> 1)) : (c >>> 1); + table[n] = c; } - - function chunk(type, data) { - const t = Buffer.from(type); - const len = Buffer.alloc(4); len.writeUInt32BE(data.length); - const crcBuf = Buffer.concat([t, data]); - const crc = Buffer.alloc(4); crc.writeUInt32BE(crc32(crcBuf)); - return Buffer.concat([len, t, data, crc]); - } - - // IHDR - const ihdr = Buffer.alloc(13); - ihdr.writeUInt32BE(width, 0); ihdr.writeUInt32BE(height, 4); - ihdr[8] = 8; ihdr[9] = 2; ihdr[10] = 0; ihdr[11] = 0; ihdr[12] = 0; - - // Pixel data: dark background with a teal circle - const rows = []; - const cx = width / 2, cy = height / 2, r = width * 0.35; - const r2 = width * 0.28; - for (let y = 0; y < height; y++) { - const row = [0]; // filter byte - for (let x = 0; x < width; x++) { - const dx = x - cx, dy = y - cy; - const dist = Math.sqrt(dx*dx + dy*dy); - if (dist < r2) { - // teal inner circle - row.push(0x4e, 0xcd, 0xc4); - } else if (dist < r) { - // slightly lighter ring - row.push(0x1a, 0x8a, 0x84); - } else { - // dark background - row.push(0x0d, 0x0d, 0x0f); - } - } - rows.push(Buffer.from(row)); - } - - // zlib compress (deflate) – minimal uncompressed blocks - const raw = Buffer.concat(rows); - // Split into 65535-byte chunks for uncompressed deflate - const chunks = []; - const CHUNK = 65535; - for (let i = 0; i < raw.length; i += CHUNK) { - const slice = raw.slice(i, i + CHUNK); - const last = i + CHUNK >= raw.length ? 1 : 0; - const hdr = Buffer.alloc(5); - hdr[0] = last; hdr.writeUInt16LE(slice.length, 1); hdr.writeUInt16LE(~slice.length & 0xffff, 3); - chunks.push(hdr, slice); - } - const deflated = Buffer.concat(chunks); - - // Adler32 - let s1 = 1, s2 = 0; - for (const b of raw) { s1 = (s1 + b) % 65521; s2 = (s2 + s1) % 65521; } - const adler = Buffer.alloc(4); adler.writeUInt32BE((s2 << 16) | s1); - - const zlib = Buffer.concat([ - Buffer.from([0x78, 0x01]), // zlib header (no compression) - deflated, - adler - ]); - - const png = Buffer.concat([ - Buffer.from([137, 80, 78, 71, 13, 10, 26, 10]), // PNG signature - chunk('IHDR', ihdr), - chunk('IDAT', zlib), - chunk('IEND', Buffer.alloc(0)) - ]); - - return png; + let crc = 0xffffffff; + for (const b of buf) crc = (table[(crc ^ b) & 0xff] ^ (crc >>> 8)); + return ((crc ^ 0xffffffff) >>> 0); } -const png192 = createPNG(192); -const png512 = createPNG(512); +function chunk(type, data) { + const t = Buffer.from(type, 'ascii'); + const len = Buffer.allocUnsafe(4); + len.writeUInt32BE(data.length, 0); + const crcInput = Buffer.concat([t, data]); + const crcBuf = Buffer.allocUnsafe(4); + crcBuf.writeUInt32BE(crc32(crcInput), 0); + return Buffer.concat([len, t, data, crcBuf]); +} -const ws192 = createWriteStream('./public/icon-192.png'); -ws192.write(png192); ws192.end(); +function deflateStore(raw) { + // zlib header (deflate, no compression) + const header = Buffer.from([0x78, 0x01]); + const blocks = []; + const SIZE = 32768; + for (let i = 0; i < raw.length; i += SIZE) { + const slice = raw.slice(i, i + SIZE); + const last = (i + SIZE >= raw.length) ? 1 : 0; + const h = Buffer.allocUnsafe(5); + h[0] = last; + h.writeUInt16LE(slice.length, 1); + h.writeUInt16LE((~slice.length) & 0xffff, 3); + blocks.push(h, slice); + } + // Adler-32 + let s1 = 1, s2 = 0; + for (const b of raw) { + s1 = (s1 + b) % 65521; + s2 = (s2 + s1) % 65521; + } + const adler = Buffer.allocUnsafe(4); + adler.writeUInt32BE(((s2 << 16) | s1) >>> 0, 0); + return Buffer.concat([header, ...blocks, adler]); +} -const ws512 = createWriteStream('./public/icon-512.png'); -ws512.write(png512); ws512.end(); +function makePNG(size) { + const cx = size / 2, cy = size / 2; + const outerR = size * 0.42, innerR = size * 0.30; -console.log('✅ Icons generiert: icon-192.png, icon-512.png'); + // IHDR + const ihdr = Buffer.allocUnsafe(13); + ihdr.writeUInt32BE(size, 0); + ihdr.writeUInt32BE(size, 4); + ihdr[8] = 8; // bit depth + ihdr[9] = 2; // RGB + ihdr[10] = ihdr[11] = ihdr[12] = 0; + + // Raw pixel data (filter byte 0 per row) + const rows = []; + for (let y = 0; y < size; y++) { + const row = Buffer.allocUnsafe(1 + size * 3); + row[0] = 0; // filter none + for (let x = 0; x < size; x++) { + const dx = x - cx, dy = y - cy; + const d = Math.sqrt(dx * dx + dy * dy); + let r, g, b; + if (d < innerR) { + r = 0x4e; g = 0xcd; b = 0xc4; // teal + } else if (d < outerR) { + r = 0x1e; g = 0x6a; b = 0x65; // dark teal ring + } else { + r = 0x0d; g = 0x0d; b = 0x0f; // background + } + row[1 + x * 3] = r; + row[2 + x * 3] = g; + row[3 + x * 3] = b; + } + rows.push(row); + } + + const raw = Buffer.concat(rows); + const idat = deflateStore(raw); + + const sig = Buffer.from([137, 80, 78, 71, 13, 10, 26, 10]); + return Buffer.concat([ + sig, + chunk('IHDR', ihdr), + chunk('IDAT', idat), + chunk('IEND', Buffer.alloc(0)), + ]); +} + +writeFileSync('./public/icon-192.png', makePNG(192)); +writeFileSync('./public/icon-512.png', makePNG(512)); +console.log('✅ Icons generiert: icon-192.png + icon-512.png');