@boundsvg/worker

Web Worker adapter for boundsvg — offloads WASM rendering to a background thread.

Installation

npm install @boundsvg/worker

Usage

import { WorkerEngine } from "@boundsvg/worker";

const engine = await WorkerEngine.create({
  worker: new URL("@boundsvg/worker/worker", import.meta.url),
  fonts: [{ alias: "Inter", weight: 400, style: "normal", data: fontBuffer }],
});

const svg = await engine.renderToSvg(scene);
engine.dispose();

Scene inputs are recursively decoded and detached before queueing, then decoded again inside the Worker because receipt is a separate trust boundary. Core SCENE_DECODE_* fatal codes, messages, stages, and contexts are preserved. WorkerPool prepares a declarative Scene once before fan-out, while materialized Scenes stay lazy until their frame is pulled.

The worker entry point is available at @boundsvg/worker/worker for bundler configuration.

WorkerEngine also exposes async text measurement methods matching the core engine:

Warning-bearing Worker responses use one top-level recoverable diagnostic list. SVG-plus-IR results retain that list as public IR.warnings, while callback values are detached so callback mutation cannot affect the returned IR. Malformed correlated responses reject the matching request; malformed uncorrelatable responses dispose the engine and reject all pending work. layoutTextFlow, layoutTextFlowWithExclusions, measureTextBlock, shrinkwrapText, shrinkwrapFlow, and measureIntrinsicInlineSize.

Documentation

Full documentation: https://github.com/zakideee/boundsvg

License

MIT OR Apache-2.0