leafer-x-metafile

Zero-dependency WMF / EMF+ metafile player: replays placeable-WMF record streams and EMF+ (GDI+) record streams into neutral, box-local drawing members — pictures, shapes, paths, and text boxes — that any renderer can consume.

Browsers cannot rasterize GDI metafiles, so Office documents carrying .wmf/.emf vector art render as empty frames. This package reassembles those byte streams (including dual-mode files whose real art hides in META_ESCAPE "WMFC" chunks as an embedded EMF+ stream) and replays them record-by-record into structured members, ready to be painted on canvas or instantiated as LeaferJS elements. Consumed by @docen/docx's layout projection, which adapts the members into its LayoutDoc drawings.

Features

• 🎞️ WMF replay — wmfMembers walks a placeable-WMF stream (pens, brushes, fonts, DC state, polygons, polylines, rectangles, ellipses, ExtTextOut with per-byte Dx tracking, StretchDIBits blts)
• 🖼️ EMF+ replay — emfPlusMembers reassembles the WMFC-carried EMF and replays its GDI+ records (fill/draw paths, draw-image points, world transforms, DrawString), layered with the GDI-side text the exporters keep there
• 🧱 DIB fallback — wmfDibFallback / bmpDataUrl re-frame the largest blt-record DIB as a BMP data URL when no vector replay applies
• 📦 Neutral output — members are plain data (MetafileMember), geometry in box-local px, text as runs; no Leafer, no DOM, no dependencies

Installation

# Install with pnpm
$ pnpm add leafer-x-metafile

# Install with npm
$ npm install leafer-x-metafile

Quick Start

import { emfPlusMembers, wmfMembers } from "leafer-x-metafile";

const bytes = new Uint8Array(/* the .wmf/.emf file */);
const members = emfPlusMembers(bytes, 400, 300) ?? wmfMembers(bytes, 400, 300);

for (const member of members ?? []) {
  if (member.kind === "path") drawPath(member.d, member.fill, member.line);
}

License

• MIT © Demo Macro