awaforge

tableCff

AGPL-3.0-onlyRelease 2L4

Table CFF — Compact Font Format Type 2 (OT §10).

Module tableCff | Source packages/front/office/fonts/src/table/cff.js | Deps fontErrors, fontReader, tableCffIndexRecord, tableCffDict, tableCffCharstring | Worker-safe yes

Parses the CFF container: 5-byte header + INDEX (Name / Top DICT / String / Global Subr), then per font the Charset / CharStrings / Private DICT / Local Subr INDEX. Type 2 charstrings are decoded glyph-by-glyph via decodeCharstring.

Exports

Symbol Type Description
parseIndex function (r: BinaryReader) => { count, offSize, offsets, data, items, end }
parseDict function Decodes an alternating stream of CFF DICT operands / operators into a Map<operator, operand[]>.
TOP_DICT_OPS const Frozen map of Top DICT operators (version, FamilyName, CharStrings, …).
parseCff function (bytes: Uint8Array) => { major, minor, hdrSize, offSize, nameIndex, topDictIndex, stringIndex, globalSubrIndex, fonts }. fonts[i] is { name, topDict, charStringsIndex, privateDict, localSubrIndex, charset }.
subrBias function Computes the Type 2 subroutine index bias (107 / 1131 / 32768).
decodeCharstring function Interprets a Type 2 charstring and returns its operations (path-like).
tableCff factory Factory { name, dependencies, factory }.

Usage

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

for (const m of [...fw_require, ...modules]) fw.runtime.register(m);
const { parseCff } = fw.runtime.resolve('tableCff');
const cff = parseCff(sfnt.tables['CFF '].bytes);
const font = cff.fonts[0];
console.log(font.topDict, font.charStringsIndex.count);

Notes

  • Header offSize ∈ {1..4} drives the offset width of every INDEX.
  • Operand 30 = real number encoded as nibbles terminated by 0xF.
  • CFF2 (uint32 count) is not supported at this level.
  • Per-font data (topDict, charStringsIndex, privateDict, localSubrIndex, charset) lives under cff.fonts[i], not at the top level.

See also

  • sfnt — host container
  • glyph/path — typical output of a decoded charstring