oconvPdfMetrics · @awacloud/oconv

Style-class face resolution and advance measurement for the md → pdf typesetter.

Module oconvPdfMetrics | Source packages/front/office/oconv/src/write/pdf/metrics.js | Deps standard14Lookup, fonts | Worker-safe yes

Resolve

import { ModuleRuntime } from '@awacloud/fw/core/runtime.js';
import { fw_require, modules } from '@awacloud/oconv';

const runtime = new ModuleRuntime();
runtime.registerAll(fw_require);
runtime.registerAll(modules);
const oconvPdfMetrics = runtime.resolve('oconvPdfMetrics');

Composed internally by ir-to-pdf; resolving it directly is for measuring text or probing font routes in isolation.

API

Member	Signature	Returns	Throws
`STYLE_CLASSES`	`string[]`	`['regular', 'bold', 'italic', 'boldItalic', 'code']`	—
`S14_FACES`	`object`	style class → Standard 14 base font name	—
`styleOfRun`	`(run: {bold?, italic?, code?}) => string`	one of `STYLE_CLASSES`	—
`winAnsiByte`	`(cp: number) => number \| null`	CP1252 byte, or `null` when unrepresentable	—
`createMeasurer`	`(opts?: {fonts?: Object<string, Uint8Array>, defaultFonts?: Object<string, Uint8Array>}) => Measurer`	frozen `Measurer`	`Error` `oconv: bad pdf font <key>` / `oconv: bad default font <key>`

Measurer members: route ('standard14' | 'embedded' | 'mixed'), face(style) (frozen face record), widthOf(text, style, sizePt) (advance sum, points), fallbacks (style classes that fell back to Standard 14 — empty on the pure Standard 14 route), s14VariantApprox (defensive flag, see Notes).

Examples

Measure text on the default (pure Standard 14) route

const measurer = oconvPdfMetrics.createMeasurer();
oconvPdfMetrics.STYLE_CLASSES;               // ['regular','bold','italic','boldItalic','code']
oconvPdfMetrics.styleOfRun({ bold: true, italic: true });  // 'boldItalic'
oconvPdfMetrics.winAnsiByte(0x20AC);         // 128 (€)
oconvPdfMetrics.winAnsiByte(0x4E2D);         // null (中, not WinAnsi-representable)
measurer.widthOf('Hi', 'regular', 12);       // 11.328 (points, Helvetica 12pt)
measurer.route;                              // 'standard14'
measurer.fallbacks;                          // []
measurer.s14VariantApprox;                   // false

Executed against the live package (2026-10-06): values exactly as shown above.

Notes

Three tiers, resolved PER STYLE CLASS, as the source implements it today: explicit opts.fonts[<class>] (caller-supplied bytes, fonts.read()) > default opts.defaultFonts[<class>] (same parse path, from the registered/posted default-face tier) > Standard 14 (standard14Lookup.lookupStandard14(name), a 256-slot 1000-units-per-em table indexed by the WinAnsi byte). No font program is vendored, embedded or downloaded by @awacloud/oconv itself.
On the pure Standard 14 route nothing "fell back": fallbacks is reported EMPTY when embeddedCount === 0 — a document that never asked for an embedded face gets no layout/font-fallback loss for it (that loss is recorded by the caller, ir-to-pdf, not by this module — this module stays pure and records no loss itself).
s14VariantApprox is a defensive probe, not a live degrade. Adobe's own Core 14 metrics give an oblique cut the same advances as its upright counterpart (slant does not change advance widths), so only a WEIGHT change (bold/boldItalic) needs a distinct width table. The flag fires only if @awacloud/fonts regresses to sharing ONE width table across Standard 14 variants (@awacloud/fonts ships real per-variant tables today) — measured false against the real package, as shown above.
opts.fonts/opts.defaultFonts keys are spelled mono for the code style class (FONT_OPT_KEY) — the option block names a FACE, the style class names a run flag; the other four keys match their style class name 1:1. An unknown key in EITHER map throws before any font is parsed (opts.fonts checked first).
WinAnsi coverage on the Standard 14 route is the full CP1252 map: the 95 printable-ASCII slots plus the 123 filled high slots (0x80-0xFF — every Latin-1 letter, every CP1252 punctuation slot winAnsiByte maps); only a genuinely unrepresentable code point degrades to the '?' width.
v1 measures plain advance sums only — no kerning, no shaping (the typesetter refuses shaping at this tier).
winAnsiByte is published here — not duplicated — so pdf/render/text encodes with the SAME CP1252 table the widths were measured with.
Worker-safe: plain data plus closures over the resolved standard14Lookup/fonts APIs; font bytes travel by structured clone. Capture-free (fw/no-factory-capture).

Resolve

API

Examples

Measure text on the default (pure Standard 14) route

Notes

See also