Table JSTF — OpenType Justification.

Module extraJstf | Source packages/front/office/fonts/src/extra/jstf.js | Deps fontErrors, fontReader, fontTag | Worker-safe yes

Decodes the JSTF header + script records. Each JstfScript sub-table (extender glyphs + JstfLangSys priority lists) is exposed by offset/bytes.

Exports

Symbol Type Description
parseJstf function (bytes) => { majorVersion, minorVersion, scriptCount, scriptRecords, scripts }. Each scripts[i] is { tag, tagStr, offset, extenderGlyphOffset, defaultLangSysOffset, langSysCount, langSysRecords } — not { jstfScriptTag, jstfScriptOffset } (jstf.js lines 56–67, readJstfScript lines 70–105).
extraJstf factory Factory.

Usage

import fw from '@awacloud/fw';
import { fw_require, modules, extras } from '@awacloud/fonts';

for (const m of [...fw_require, ...modules, ...extras]) fw.runtime.register(m);
const { parseJstf } = fw.runtime.resolve('extraJstf');
const jstf = parseJstf(sfnt.tables.JSTF.bytes);

Notes

  • JstfScript / JstfLangSys / JstfPriority bodies are left as Uint8Array for deferred decoding.
  • Included in fonts-large.

See also