PDF

Install

PDF support is a small add-on package. It depends on pdf.js ( pdfjs-dist).

pnpm add @zinejs/core @zinejs/pdf

PdfSource

Pass a URL, raw bytes ( ArrayBuffer / Uint8Array), or a pre-created pdf.js document. Under most bundlers the worker is auto-resolved.

import { Zine } from '@zinejs/core'
import { PdfSource } from '@zinejs/pdf'

new Zine(document.getElementById('book'), {
  source: new PdfSource('/catalog.pdf', { progressive: true }),
})

Options

workerSrcoptional · default auto

URL to the pdf.js worker. Auto-resolved under bundlers; pass it for CDN, UMD, or custom paths.

renderScaledefault 1

Base raster scale. Each page paints at renderScale × devicePixelRatio.

preloaddefault 1

How many adjacent pages to prefetch around a requested page.

maxCacheBytesdefault ~256 MB

Soft cap on cached page bytes. Least-recently-used pages are evicted beyond this limit.

progressivedefault false

Paint a low-res page first, then swap to crisp for a faster first paint.

disableAutoFetchdefault false

Fetch only the byte ranges visible pages need. Requires a range-capable server.

legacydefault true

Load pdf.js's transpiled legacy build (polyfills, broader reach) and the matching worker. Pass false for the smaller modern build on recent engines only. Ignored when you pass a pre-created document or set globalThis.pdfjsLib (CDN).

// Optional: pass workerSrc for CDN / UMD / custom paths
// Under Vite / webpack the worker is usually auto-resolved.
import pdfWorker from 'pdfjs-dist/legacy/build/pdf.worker.min.mjs?url'

new PdfSource('/catalog.pdf', {
  workerSrc: pdfWorker,
  renderScale: 1,
  preload: 1,
  progressive: true,
})

Browser support

Image books need ordinary DOM, canvas, and fetch / createImageBitmap. PDF books go through pdf.js. The default legacy: true path is aimed at a wide range of engines. Mozilla documents the legacy build as Chrome 125+, Firefox ESR, Safari 18+, and Chromium Edge. In our tests, PDF text rasterizes correctly back to Chrome 114.

Where WebGL2 is unavailable, zinejs falls back to the CSS renderer on its own.

See the PDF example.