# Un atlas scolaire étiqueté depuis le Markdown

> Des cartes peintes sans une lettre, nommées par des lignes ::label aux ancres de chaque ressource, en pages composées et sur double page, en trois langues.

- Version HTML: https://postext.dev/fr/cookbook/school-atlas-labelled-maps
- Recette Nº 157 · Figures et images · Niveau 3 (Avancé) · Sorties: Canvas
- Genres: Manuels scolaires
- Nécessite postext ≥ 1.39.0 · testée avec 1.39.0 le 2026-10-17
- Pages: [1](https://postext.dev/cookbook/school-atlas-labelled-maps/en/p01.webp?v=d082d69c), [2](https://postext.dev/cookbook/school-atlas-labelled-maps/en/p02.webp?v=d082d69c), [3](https://postext.dev/cookbook/school-atlas-labelled-maps/en/p03.webp?v=d082d69c), [4](https://postext.dev/cookbook/school-atlas-labelled-maps/en/p04.webp?v=d082d69c)
- Ouvrir dans le Sandbox: https://postext.dev/fr/sandbox#recipe=school-atlas-labelled-maps&lang=en (.postext: https://postext.dev/cookbook/school-atlas-labelled-maps/en/school-atlas-labelled-maps.postext)
- Dernière mise à jour: 2026-10-17
- Autres langues: [en](https://postext.dev/en/cookbook/school-atlas-labelled-maps.md), [es](https://postext.dev/es/cookbook/school-atlas-labelled-maps.md), [ca](https://postext.dev/ca/cookbook/school-atlas-labelled-maps.md), [de](https://postext.dev/de/cookbook/school-atlas-labelled-maps.md), [it](https://postext.dev/it/cookbook/school-atlas-labelled-maps.md), [pt](https://postext.dev/pt/cookbook/school-atlas-labelled-maps.md), [zh](https://postext.dev/zh/cookbook/school-atlas-labelled-maps.md), [ja](https://postext.dev/ja/cookbook/school-atlas-labelled-maps.md), [ar](https://postext.dev/ar/cookbook/school-atlas-labelled-maps.md)

## En bref

Trois pages d’un atlas scolaire d’un pays inventé. Les cartes sont des peintures sans texte ; tous leurs noms s’écrivent dans le texte, si bien qu’une traduction change les mots et laisse les cartes telles quelles.

## Ce que vous allez composer

Trois planches d’un atlas scolaire de Varenia, un pays inventé pour cette recette. La planche 1 le situe sur son continent. La planche 2 étend la carte du relief sur les deux pages, de la mer de Lira à la frontière avec Brunavia, en teintes hypsométriques, avec trois fleuves et le tracé d’une coupe. La planche 3 dessine cette coupe à travers la chaîne d’Albar. Chaque planche s’ouvre sur un bandeau bleu et se ferme sur une légende ou un lexique et quelques activités pour la classe. Les trois cartes sont des peintures faites avec un modèle d’image et ne portent aucune lettre ; les frontières, les villes, la ligne de coupe, l’échelle et la flèche du nord sont des symboles vectoriels posés dessus. Les 43 noms, altitudes et chiffres de l’échelle sont des lignes `::label` du Markdown, posées sur des ancres que chaque carte garde avec elle. Les éditions espagnole, anglaise et arabe partagent donc les trois peintures, et l’arabe se lit et se relie par la droite.

**Cette recette répond à:**

- Comment poser les noms d’une carte depuis le texte, pour que chaque traduction garde le même dessin ?
- Comment étendre une carte sur une double page et garder ses noms lisibles dans une édition de droite à gauche ?

## La réponse courte

```js
// script.js, lignes 43–68
// A label takes the style its anchor names: seas and rivers in italic blue, ranges in spaced
// brown capitals, towns on a white halo. Arabic is neither slanted nor letter-spaced, and
// Naskh and Kufi set small, so the Arabic edition gets the same styles upright, unspaced and
// 15 % larger.
const [SLANT, TRACK, SIZE] = AR ? ['normal', 0, 1.15] : ['italic', 1, 1];
const halo = { color: col('paper'), width: pt(1.4) };
const style = (id, size, color, more) => ({ id, fontFamily: LABEL, fontSize: pt(size * SIZE),
  fontWeight: AR ? 500 : 400, color: col(color), ...more });
const water = (id, size, spacing, more) => style(id, size, 'water', { fontStyle: SLANT,
  textTransform: spacing ? 'uppercase' : 'none', letterSpacing: spacing * TRACK, ...more });
const caps = (id, size, color, spacing, more) => style(id, size, color, {
  fontWeight: AR ? 700 : 600, textTransform: 'uppercase', letterSpacing: spacing * TRACK,
  ...more });
const labelStyles = [
  water('ocean', 9.5, 0.3), water('sea', 7.5, 0.16), water('river', 6.8, 0, { halo }),
  caps('range', 7, 'relief', 0.32, { halo }), caps('region', 6.5, 'muted', 0.24, { halo }),
  caps('country', 8.5, 'muted', 0.36, { halo }), caps('nation', 12, 'ink', 0.42, { halo }),
  style('capital', 7.6, 'ink', { fontWeight: 700, halo }), style('town', 7, 'ink', { halo }),
  style('peak', 6.5, 'ink', { fontWeight: AR ? 700 : 600, halo }),
  style('island', 6.5, 'ink', { halo }),
  style('point', 8.5, 'band', { fontWeight: 700, halo }), style('tick', 6, 'muted'),
];
// An anchor is a point of the picture in fractions of its width and height, with the side of
// the label that stands there, its turn and its style. km(win) reads a point in km off a map.
const km = (win) => (id, x, y, labelStyle, more) => ({ id, x: (x - win.x0) / (win.x1 - win.x0),
  y: (y - win.y0) / (win.y1 - win.y0), style: labelStyle, ...more });
```

## Ingrédients

**Enseigne**

- [Étiquettes sur l’image](https://postext.dev/fr/docs/composed-pages.md#figures-avec-étiquettes): :::figure{resource} avec une ligne ::label[TEXTE]{at} par nom : chaque étiquette se place sur une ancre de la ressource (un point avec son côté, sa rotation, sa mesure et son style) ou en x% y%, dans un style de labelStyles, et le dessin ne porte aucune lettre.
- [Modèles en double page](https://postext.dev/fr/docs/composed-pages.md#doubles-pages): Un modèle avec spread: true met en page deux pages en vis-à-vis comme une seule feuille à partir d’une page paire ; un bloc avec crossGutter traverse le dos, les autres s’écartent de la bande du petit fond.
- [Pages composées](https://postext.dev/fr/docs/composed-pages.md#pages-composées): Une page tirée d’un gabarit de blocs nommés dans la configuration, remplie par un bloc ::::page dont le contenu désigne chaque bloc par son slot.

**Utilise aussi**

- [Blocs qui s’agrandissent dans un groupe](https://postext.dev/fr/docs/composed-pages.md#quand-le-texte-sallonge)
- [Pastilles de couleur](https://postext.dev/fr/docs/document-format-inline.md#mise-en-forme-en-ligne)
- [Texte de droite à gauche](https://postext.dev/fr/docs/arabic-layout.md#sens-décriture-et-algorithme-bidirectionnel)
- [Livres reliés à droite](https://postext.dev/fr/docs/configuration-page-layout.md#reliure)
- [Polices arabes](https://postext.dev/fr/docs/arabic-layout.md#polices)
- [Figures et tableaux comme ressources](https://postext.dev/fr/docs/document-format-resources.md#ressources)
- [Types de ressource personnalisés](https://postext.dev/fr/docs/configuration-resources.md#types-de-ressources)
- [Encadrés](https://postext.dev/fr/docs/configuration-callouts.md#styles-dencadré)
- [Listes numérotées](https://postext.dev/fr/docs/configuration-lists-math.md#listes-numérotées)
- [Styles de paragraphe](https://postext.dev/fr/docs/configuration-styles.md#styles-de-paragraphe)
- [Texte, filets et boîtes dans les maquettes de page](https://postext.dev/fr/docs/configuration-headers-footers.md#en-têtes-et-pieds-de-page)
- [Marges en miroir](https://postext.dev/fr/docs/configuration-page-layout.md#marges-en-miroir)
- [Palette de couleurs sémantique](https://postext.dev/fr/docs/configuration-fonts-colors-viewers.md#palette-de-couleurs)
- [Pages sur un canvas](https://postext.dev/fr/docs/configuration-programmatic-usage.md#rendre-une-page-en-bitmap)
- [Décor ancré aux blocs](https://postext.dev/fr/docs/composed-pages.md#décor-titres-courants-et-calques)

**La configuration en un coup d’œil**

- [`bodyText`](https://postext.dev/fr/docs/configuration-text.md#texte-courant), [`calloutStyles`](https://postext.dev/fr/docs/configuration-callouts.md#styles-dencadré), [`colorPalette`](https://postext.dev/fr/docs/configuration-fonts-colors-viewers.md#palette-de-couleurs), [`footer`](https://postext.dev/fr/docs/configuration-headers-footers.md#en-têtes-et-pieds-de-page), [`header`](https://postext.dev/fr/docs/configuration-headers-footers.md#en-têtes-et-pieds-de-page), [`headings`](https://postext.dev/fr/docs/configuration-headings.md#titres), [`labelStyles`](https://postext.dev/fr/docs/configuration-composed-pages.md#styles-détiquette), [`layout`](https://postext.dev/fr/docs/configuration-page-layout.md#mise-en-page), [`locale`](https://postext.dev/fr/docs/configuration-language.md#césure), [`orderedLists`](https://postext.dev/fr/docs/configuration-lists-math.md#listes-numérotées), [`page`](https://postext.dev/fr/docs/configuration-page-layout.md#page), [`pageTemplates`](https://postext.dev/fr/docs/configuration-composed-pages.md#gabarits-de-page), [`paragraphStyles`](https://postext.dev/fr/docs/configuration-styles.md#styles-de-paragraphe), [`resourceTypes`](https://postext.dev/fr/docs/configuration-resources.md#types-de-ressources)

**API**

- [`buildDocument`](https://postext.dev/fr/docs/configuration-programmatic-usage.md#construire-un-document), [`registerResourceImage`](https://postext.dev/fr/docs/architecture.md#surface-de-lapi), [`renderPageToCanvas`](https://postext.dev/fr/docs/configuration-programmatic-usage.md#rendre-une-page-en-bitmap), [`withLoadedFonts`](https://postext.dev/fr/docs/configuration-programmatic-usage.md#charger-les-polices-avant-la-mise-en-page)

**Caractères**

- Source Sans 3 (OFL-1.1), Source Serif 4 (OFL-1.1), Noto Naskh Arabic (OFL-1.1), Noto Kufi Arabic (OFL-1.1)

## Préparation

### 1 · Un lieu est un point du dessin

```js
// script.js, lignes 421–463
const above = { verticalAlign: 'bottom' }, below = { verticalAlign: 'top' };
const r = km(WIN.relief), l = km(WIN.locator);
const ANCHORS = {
  relief: [
    r('ocean', 172, 157, 'ocean'), r('lira', 20, 52, 'sea', { rotate: -84 }),
    r('gulf', 318, 154, 'sea', { width: 0.07 }), r('nema', 22, 100, 'island', above),
    r('albar-range', 98, 108, 'range', { rotate: -33 }),
    r('gris-range', 308, 96, 'range', { rotate: -86 }),
    r('plateau', 236, 78, 'region'), r('plain', 70, 98, 'region', { width: 0.08 }),
    r('sela', 108, 62, 'river', { rotate: -4 }), r('duna', 121, 136, 'river', { rotate: -62 }),
    r('merel', 281, 92, 'river', { rotate: -47 }), r('ormo', 254, 104, 'river', above),
    // Calvera's name goes below its dot: the River Sela runs in just above it.
    ...TOWNS.map(([id, x, y]) => (id === 'calvera' ? r(id, x, y + 2.6, 'town', below)
      : r(id, x, y - 2.6, id === 'almaren' ? 'capital' : 'town', above))),
    ...PEAKS.map(([id, x, y]) => r(`${id}-peak`, x, y + 2.4, 'peak', below)),
    r('ostelia', 300, 9, 'country'), r('brunavia', 390, 112, 'country', { rotate: -90 }),
    r('varenia', 250, 46, 'nation'),
    r('a', PROFILE[0][0], PROFILE[0][1] - 2, 'point', above),
    r('b', PROFILE[1][0], PROFILE[1][1] + 2, 'point', below),
    r('scale-0', SCALE.x, SCALE.y + 3, 'tick', below),
    r('scale-25', SCALE.x + 25, SCALE.y + 3, 'tick', below),
    r('scale-50', SCALE.x + 50, SCALE.y + 3, 'tick', below),
    r('north', NORTH.x, NORTH.y - 8, 'point', above),
  ],
  locator: [
    l('varenia', 205, 80, 'nation'), l('ostelia', 150, -100, 'country'),
    l('brunavia', 560, -120, 'country'), l('lira', 210, -250, 'sea', { rotate: 20 }),
    l('ocean', -180, -40, 'ocean', { width: 0.2 }), l('almaren', 259, 127 + 22, 'capital', below),
  ],
  // The section: fractions of the drawing, whose plot starts 14 mm in and runs 3 to 51 mm down.
  section: (() => {
    const [w, h] = MAP.section, x = (u) => (14 + u * (w - 14)) / w;
    const y = (m) => (h - 7 - m * (h - 10) / PROFILE_TOP) / h;
    return [
      { id: 'a', x: x(0), y: (h - 5.5) / h, style: 'point', ...below },
      { id: 'b', x: x(0.98), y: (h - 5.5) / h, style: 'point', ...below },
      ...[500, 1000, 1500, 2000].map((m) => ({ id: `m${m}`, x: 7 / w, y: y(m), style: 'tick' })),
      { id: 'sela', x: x(0.3), y: y(380), style: 'region' },
      { id: 'crest', x: x(0.47), y: y(2260), style: 'range', ...above },
      { id: 'plain', x: x(0.82), y: y(430), style: 'region' },
    ];
  })(),
};
```

Une ancre est un point exprimé en fractions de la largeur et de la hauteur de l’image : elle tient à toutes les tailles où le bloc pose la carte, et quand la cascade de recomposition réduit une carte, ses noms la suivent. `km()` convertit en fractions les kilomètres lus sur une grille posée sur la peinture : le point d’une ville et son nom viennent tous deux de `TOWNS` et ne peuvent pas se séparer. L’ancre porte ce qui appartient au lieu et non à la langue : son style, la rotation du nom d’un fleuve ou d’une chaîne le long de son cours, le côté de l’étiquette qui s’appuie sur le point. Les noms de ville sont centrés au-dessus de leur point, car `align: 'start'` désignerait la gauche d’un nom anglais et la droite d’un nom arabe.

Les peintures ont été faites dans l’ordre. La planche du relief d’abord, peinte par un modèle d’image à partir d’une carte des altitudes du pays aux reliefs ombrés ; la carte de situation a été peinte à partir de la planche du relief, et la coupe avec les mêmes altitudes, si bien que côtes et altitudes s’accordent sur les trois. Une grille tracée sur chaque image a donné les kilomètres de chaque ancre, et les frontières ont été coupées là où elles atteignent la côte peinte.

### 2 · Trois fichiers Markdown, une seule ressource

```js
// script.js, lignes 467–477
// A resource has no alt text, caption or note here: each edition's `:::figure` says its own.
const PAINTINGS = { // each plate's painting, a file in assets/, named by its width in pixels
  locator: asset('locator-1776.jpg'), relief: asset('relief-1984.jpg'),
  section: asset('section-1760.jpg') };
const drawings = { locator: locatorMap, relief: reliefMap, section: profile };
const resources = Object.entries(MAP).map(([id, [w, h]]) => ({ id, typeId: 'map', kind: 'svg',
  createdAt: 0, updatedAt: 0, svg: { fileId: `${id}.svg`, width: w * 10, height: h * 10 },
  anchors: ANCHORS[id] }));
for (const [id, draw] of Object.entries(drawings)) {
  await loadSvg(`${id}.svg`, draw(MAP[id], await dataUrl(PAINTINGS[id])));
}
```

La ressource a une seule image (un SVG qui porte la peinture et, dessus, les symboles vectoriels) et une seule liste d’ancres pour toutes les éditions. Chaque édition écrit une ligne `::label[…]{at="…"}` par ancre dans `:::figure{resource="relief" slot="map"}` : `::label[Calvera Plain]{at="plain"}` et `::label[Llanura de Calvera]{at="plain"}` se posent au même endroit, coupés sur deux lignes par le `width` de l’ancre quand il le faut. Le texte alternatif change aussi d’une édition à l’autre : chaque `:::figure` porte le sien dans une ligne `::alt[…]`, et une légende ou une note iraient de même avec `::caption[…]` et `::note[…]`. Une ancre dotée d’un style qu’une édition laisse sans étiquette produit l’avertissement `anchorUnlabelled`, et une étiquette dont le `at` ne nomme aucune ancre n’est pas dessinée et produit `labelAnchorUnknown`.

### 3 · Une planche simple et une planche double

```js
// script.js, lignes 72–105
const at = (to, edge, x = 0, y = 0) => ({ anchor: { to, edge }, offset: { x: mm(x), y: mm(y) } });
const kicker = { kind: 'text', id: 'unit', content: '{attr.unit}', fontFamily: LABEL,
  fontSize: pt(AR ? 10 : 8.5), fontWeight: AR ? 500 : 600, letterSpacing: pt(1.3 * TRACK),
  textTransform: 'uppercase', color: col('sky'), align: AR ? 'right' : 'left',
  // Decoration stands on the sheet: the kicker goes to the side the page starts reading from.
  placement: at('container', AR ? 'top-right' : 'top-left', 0, -11) };
const band = { kind: 'box', id: 'band', style: { backgroundColor: col('band') },
  placement: { ...at('bleed', 'top-left'), size: { width: 'fill', height: mm(BAND + 3) } } };
const sheet = {
  id: 'sheet', header: false, decoration: { elements: [band, kicker] },
  frames: [
    { name: 'title', takes: 'h1', placement: at('container', 'top-left', 0, -3) },
    { name: 'text', flow: true, columns: 2, columnGap: mm(7),
      placement: at('container', 'top-left', 0, BAND - PAGE.top + 7) },
    { name: 'map' },
    { name: 'key', style: 'key', width: mm(66) },
    { name: 'tasks', style: 'tasks', placement: at('#key', 'right-of', 6) },
  ],
  // A longer text pushes the map and the key down; the map is set smaller before the text is.
  groups: [{ name: 'column', kind: 'stack', frames: ['text', 'map', 'key'], gap: mm(6) }],
};
// The double sheet: one band and one map across both pages, the boxes under the map.
const spread = {
  id: 'spread', spread: true, header: false, decoration: { elements: [band, kicker] },
  frames: [
    { name: 'title', takes: 'h1', width: mm(177), placement: at('container', 'top-left', 0, -3) },
    { name: 'map', crossGutter: true, // the one frame that runs across the spine
      placement: at('container', 'top-left', 0, BAND - PAGE.top + 5) },
    { name: 'text', flow: true, columns: 2, columnGap: mm(7), width: mm(177) },
    { name: 'key', style: 'key', width: mm(72), placement: at('#map', 'below', 213, 6) },
    { name: 'tasks', style: 'tasks', placement: at('#key', 'right-of', 6) },
  ],
  groups: [{ name: 'column', kind: 'stack', frames: ['map', 'text'], gap: mm(6) }],
};
```

Les deux modèles ont les mêmes cinq blocs, si bien que le Markdown d’une planche a la même forme sur une page ou sur deux : le titre, le texte qui ne nomme aucun emplacement, la carte, la légende et les activités. Sur la planche double, `spread: true` met en page les deux pages comme une seule feuille de 390 mm, et seul le bloc de la carte porte `crossGutter` : il passe par-dessus le dos tandis que le texte et les encadrés restent sur leur page. Le texte, la carte et la légende forment un groupe `stack` ; dans le test de charge du banc d’essai, avec tous les textes allongés de 30 %, l’édition arabe pose la carte de situation à 87,5 % et les encadrés remontent sous elle, sans aucun avertissement.

### 4 · Une palette pour la page, les teintes et la légende

```js
// script.js, lignes 19–33
const palette = {
  ink: '#1f2a2e', paper: '#ffffff', muted: '#55646a',
  band: '#1d5f73', // the accent: the head of each sheet, box stripes, list numbers
  sky: '#d4e9f2', // the kicker on the band
  tint: '#eef2ef', // the key's box
  water: '#0b2a47', sea: '#8ec5e9', // the names of water, and the sea of the key
  // The key's tints are the median colours of the painted relief at each height band.
  low: '#aec67f', hill: '#ced285', upland: '#efce80', mount: '#d79c61', peak: '#b5734b',
  relief: '#5a3519', // the names of ranges
  land: '#e1dfbe', country: '#ebcb73', border: '#8a3b52', // the locator map's washes and border
};
// col(id) links a colour to its palette entry; the vector symbols read the same hex from `palette`.
const col = (id) => ({ hex: palette[id], model: 'hex', paletteId: id });
const colorPalette = Object.entries({ ...palette, 'main-color': palette.band }) // the defaults' id
  .map(([id, hex]) => ({ id, name: id, value: { hex, model: 'hex' } }));
```

Les cinq teintes d’altitude sont des entrées de la palette (`palette.low` à `palette.peak`), réglées sur la couleur médiane du relief peint dans chaque bande, et la légende de la planche 2 écrit `:swatch{color="low"}` avec les mêmes identifiants. La peinture ne lit pas la palette : une nouvelle valeur hexadécimale change la légende et les symboles vectoriels et laisse l’image telle quelle ; pour changer les couleurs de la carte, il faut la repeindre. Les noms d’eau, en `water`, ont un contraste d’au moins 6:1 sur la mer peinte, et le titre blanc de 7,2:1 sur `band`.

### 5 · L’édition arabe

Le code est dans [la réponse courte](https://postext.dev/fr/cookbook/school-atlas-labelled-maps.md#la-réponse-courte) ci-dessus. `locale: 'ar'` compose le texte de droite à gauche et relie le livre à droite : la double page s’ouvre sur la page de droite, et les blocs suivent la zone de contenu en miroir, le titre et le texte à droite, la légende à droite des activités. Les cartes ne sont pas inversées, et chaque nom arabe se pose là où son lieu est dessiné. En arabe, les styles d’étiquette perdent l’italique et l’interlettrage et grandissent de 15 %, car le coufique compose petit. Le décor et les folios restent sur la feuille : le surtitre passe en haut à droite et les folios changent de côté.

## La recette complète

Un seul fichier, composé à partir du dossier de la recette avec le texte d’exemple et le kit commun des Recettes déjà inclus ; il construit sa propre page. Pour l’exécuter, placez-le dans un `<script type="module">` d’une page vide ou collez-le dans le panneau JS d’un nouveau pen CodePen (en tant que module). Il importe postext depuis esm.sh : il n’y a rien à installer ni à compiler.

- Dossier de la recette: https://github.com/drnachio/postext/tree/main/cookbook/school-atlas-labelled-maps

### script.js

```js
// ═══ Postext Cookbook · Nº 157 · A school atlas labelled from the Markdown ═══════
// https://postext.dev/en/cookbook/school-atlas-labelled-maps
// Code: MIT · Text: original (CC BY 4.0) · Maps: painted with diffusion models, symbols set in code
// Fonts: Source Sans 3, Source Serif 4, Noto Naskh and Kufi Arabic (OFL) · Needs postext ≥ 1.39.0
//
// Three pages of a school atlas of Varenia, an invented country: a locator map, the relief map
// across a double page and a section through the mountains. The maps are painted without a letter.
// Every name on them is a ::label in content.<lang>.md, standing at an anchor of the resource,
// so the Spanish, English and Arabic editions share the same paintings and the same anchors.
import {
  buildDocument, withLoadedFonts, renderPageToCanvas, registerResourceImage,
} from 'https://esm.sh/postext';

const LANG = 'en'; // @lang: the language of the sample document ('es' | 'en' | 'ar')
const RECIPE = 'school-atlas-labelled-maps';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: the page's colours and the key's tints, one object for both
const palette = {
  ink: '#1f2a2e', paper: '#ffffff', muted: '#55646a',
  band: '#1d5f73', // the accent: the head of each sheet, box stripes, list numbers
  sky: '#d4e9f2', // the kicker on the band
  tint: '#eef2ef', // the key's box
  water: '#0b2a47', sea: '#8ec5e9', // the names of water, and the sea of the key
  // The key's tints are the median colours of the painted relief at each height band.
  low: '#aec67f', hill: '#ced285', upland: '#efce80', mount: '#d79c61', peak: '#b5734b',
  relief: '#5a3519', // the names of ranges
  land: '#e1dfbe', country: '#ebcb73', border: '#8a3b52', // the locator map's washes and border
};
// col(id) links a colour to its palette entry; the vector symbols read the same hex from `palette`.
const col = (id) => ({ hex: palette[id], model: 'hex', paletteId: id });
const colorPalette = Object.entries({ ...palette, 'main-color': palette.band }) // the defaults' id
  .map(([id, hex]) => ({ id, name: id, value: { hex, model: 'hex' } }));
// #endregion
const AR = LANG === 'ar';
// Three voices per script: a text face, a display face and the face of the map labels.
const [TEXT, DISPLAY, LABEL] = AR ? ['Noto Naskh Arabic', 'Noto Kufi Arabic', 'Noto Kufi Arabic']
  : ['Source Sans 3', 'Source Serif 4', 'Source Sans 3'];
const PAGE = { w: 210, h: 280, top: 22, bottom: 20, inner: 18, outer: 15 }; // mm, mirrored
const BAND = 44; // mm from the trim to the foot of the band at the head of a sheet

// #region answer: label styles in the config, label fields on the anchors of a resource
// A label takes the style its anchor names: seas and rivers in italic blue, ranges in spaced
// brown capitals, towns on a white halo. Arabic is neither slanted nor letter-spaced, and
// Naskh and Kufi set small, so the Arabic edition gets the same styles upright, unspaced and
// 15 % larger.
const [SLANT, TRACK, SIZE] = AR ? ['normal', 0, 1.15] : ['italic', 1, 1];
const halo = { color: col('paper'), width: pt(1.4) };
const style = (id, size, color, more) => ({ id, fontFamily: LABEL, fontSize: pt(size * SIZE),
  fontWeight: AR ? 500 : 400, color: col(color), ...more });
const water = (id, size, spacing, more) => style(id, size, 'water', { fontStyle: SLANT,
  textTransform: spacing ? 'uppercase' : 'none', letterSpacing: spacing * TRACK, ...more });
const caps = (id, size, color, spacing, more) => style(id, size, color, {
  fontWeight: AR ? 700 : 600, textTransform: 'uppercase', letterSpacing: spacing * TRACK,
  ...more });
const labelStyles = [
  water('ocean', 9.5, 0.3), water('sea', 7.5, 0.16), water('river', 6.8, 0, { halo }),
  caps('range', 7, 'relief', 0.32, { halo }), caps('region', 6.5, 'muted', 0.24, { halo }),
  caps('country', 8.5, 'muted', 0.36, { halo }), caps('nation', 12, 'ink', 0.42, { halo }),
  style('capital', 7.6, 'ink', { fontWeight: 700, halo }), style('town', 7, 'ink', { halo }),
  style('peak', 6.5, 'ink', { fontWeight: AR ? 700 : 600, halo }),
  style('island', 6.5, 'ink', { halo }),
  style('point', 8.5, 'band', { fontWeight: 700, halo }), style('tick', 6, 'muted'),
];
// An anchor is a point of the picture in fractions of its width and height, with the side of
// the label that stands there, its turn and its style. km(win) reads a point in km off a map.
const km = (win) => (id, x, y, labelStyle, more) => ({ id, x: (x - win.x0) / (win.x1 - win.x0),
  y: (y - win.y0) / (win.y1 - win.y0), style: labelStyle, ...more });
// #endregion

// #region templates: a sheet and a double sheet, each a band, a text, a map and two boxes
const at = (to, edge, x = 0, y = 0) => ({ anchor: { to, edge }, offset: { x: mm(x), y: mm(y) } });
const kicker = { kind: 'text', id: 'unit', content: '{attr.unit}', fontFamily: LABEL,
  fontSize: pt(AR ? 10 : 8.5), fontWeight: AR ? 500 : 600, letterSpacing: pt(1.3 * TRACK),
  textTransform: 'uppercase', color: col('sky'), align: AR ? 'right' : 'left',
  // Decoration stands on the sheet: the kicker goes to the side the page starts reading from.
  placement: at('container', AR ? 'top-right' : 'top-left', 0, -11) };
const band = { kind: 'box', id: 'band', style: { backgroundColor: col('band') },
  placement: { ...at('bleed', 'top-left'), size: { width: 'fill', height: mm(BAND + 3) } } };
const sheet = {
  id: 'sheet', header: false, decoration: { elements: [band, kicker] },
  frames: [
    { name: 'title', takes: 'h1', placement: at('container', 'top-left', 0, -3) },
    { name: 'text', flow: true, columns: 2, columnGap: mm(7),
      placement: at('container', 'top-left', 0, BAND - PAGE.top + 7) },
    { name: 'map' },
    { name: 'key', style: 'key', width: mm(66) },
    { name: 'tasks', style: 'tasks', placement: at('#key', 'right-of', 6) },
  ],
  // A longer text pushes the map and the key down; the map is set smaller before the text is.
  groups: [{ name: 'column', kind: 'stack', frames: ['text', 'map', 'key'], gap: mm(6) }],
};
// The double sheet: one band and one map across both pages, the boxes under the map.
const spread = {
  id: 'spread', spread: true, header: false, decoration: { elements: [band, kicker] },
  frames: [
    { name: 'title', takes: 'h1', width: mm(177), placement: at('container', 'top-left', 0, -3) },
    { name: 'map', crossGutter: true, // the one frame that runs across the spine
      placement: at('container', 'top-left', 0, BAND - PAGE.top + 5) },
    { name: 'text', flow: true, columns: 2, columnGap: mm(7), width: mm(177) },
    { name: 'key', style: 'key', width: mm(72), placement: at('#map', 'below', 213, 6) },
    { name: 'tasks', style: 'tasks', placement: at('#key', 'right-of', 6) },
  ],
  groups: [{ name: 'column', kind: 'stack', frames: ['map', 'text'], gap: mm(6) }],
};
// #endregion

// Boxes: the key on a pale blue tint, the tasks behind a stripe in the band's blue.
const boxText = { fontFamily: TEXT, fontSize: pt(AR ? 10.5 : 8.6), lineHeight: pt(AR ? 17 : 12),
  color: col('ink'), boldColor: col('ink'), italicColor: col('ink'), firstLineIndent: pt(0),
  textAlign: 'start' }; // ragged in every script: a box's short lines are never stretched
const boxTitle = { fontFamily: LABEL, fontSize: pt(AR ? 9.5 : 8), fontWeight: 700,
  letterSpacing: pt(1.2 * TRACK), textTransform: 'uppercase', color: col('band') };
const calloutStyles = [
  { id: 'key', backgroundEnabled: true, background: col('tint'), border: { enabled: false },
    padding: { top: mm(3), right: mm(3.5), bottom: mm(3), left: mm(3.5) },
    titleStyle: boxTitle, body: boxText },
  { id: 'tasks', backgroundEnabled: false, border: { enabled: false },
    stripe: { enabled: true, side: 'top', width: pt(2.5), color: col('band') },
    padding: { top: mm(2.5), right: mm(0), bottom: mm(0), left: mm(0) },
    titleStyle: boxTitle, body: boxText },
];

// The folio and the atlas's name at the foot, on the outer side. An Arabic book is bound on the
// right, so its rectos (odd pages) stand left of the spine and their outer edge is the left.
const foot = (parity) => {
  const left = (parity === 'even') !== AR;
  const text = (id, content, x, extra) => ({ kind: 'text', id: `${id}-${parity}`, content, parity,
    fontFamily: LABEL, fontSize: pt(AR ? 9 : 8), fontWeight: AR ? 500 : 400, color: col('muted'),
    align: left ? 'left' : 'right', ...extra,
    placement: at('page', left ? 'bottom-left' : 'bottom-right', left ? x : -x, -11) });
  return [text('folio', '{pageNumber}', PAGE.outer, { fontWeight: 700, color: col('band') }),
    text('title', '{title}', PAGE.outer + 8)];
};
const footer = { elements: [...foot('even'), ...foot('odd')] };

const config = {
  locale: t({ es: 'es', en: 'en-gb', ar: 'ar' }), // written out: Arabic sets the page right to left
  colorPalette, labelStyles, calloutStyles, footer,
  header: { elements: [] },
  pageTemplates: [sheet, spread],
  // The maps are a type of their own with no caption: their titles are the pages' headings.
  resourceTypes: [{ id: 'map', name: t({ es: 'Mapa', en: 'Map', ar: 'خريطة' }), shortLabel: '',
    numberingTemplate: '', resetOn: 'never', counterFormat: 'decimal', captionPrefix: '',
    defaultPlacement: { position: 'here' } }],
  page: { sizePreset: 'custom', width: mm(PAGE.w), height: mm(PAGE.h), dpi: 150,
    margins: { top: mm(PAGE.top), bottom: mm(PAGE.bottom), left: mm(PAGE.inner),
      right: mm(PAGE.outer), mirror: true } },
  layout: { layoutType: 'single' },
  bodyText: AR
    ? { fontFamily: TEXT, fontSize: pt(12), lineHeight: pt(20), color: col('ink'),
      boldColor: col('ink'), italicColor: col('ink'), referenceColor: col('ink'),
      textAlign: 'justify', firstLineIndent: em(1), hyphenation: { enabled: false } }
    : { fontFamily: TEXT, fontSize: pt(10), lineHeight: pt(14), color: col('ink'),
      boldColor: col('ink'), italicColor: col('ink'), referenceColor: col('ink'),
      textAlign: 'left', firstLineIndent: mm(0), paragraphSpacing: true,
      hyphenation: { enabled: true }, optimalLineBreaking: true, avoidWidows: true,
      avoidOrphans: true, avoidRunts: true },
  headings: { fontFamily: DISPLAY, fontWeight: 700, color: col('paper'), levels: [
    { level: 1, fontSize: pt(AR ? 24 : 26), lineHeight: pt(AR ? 34 : 30),
      marginTop: pt(0), marginBottom: pt(0), breakBefore: { enabled: false } },
  ] },
  orderedLists: { numberFormat: 'arabic', color: col('band'), fontWeight: 700,
    marginTop: pt(0), marginBottom: pt(0) },
  paragraphStyles: [{ id: 'colophon', fontFamily: TEXT, fontSize: pt(AR ? 8.5 : 7.5),
    lineHeight: pt(AR ? 14 : 10), color: col('muted'), textAlign: 'start',
    firstLineIndent: pt(0) }],
};

// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = String.raw`---
title: "A School Atlas of Varenia"
---

::::page{template="sheet" unit="Plate 1 · Location"}
# Varenia on the map

Varenia is a country in the south of the continent, with Ostelia to the north and Brunavia to the east. The Lira Sea washes its west coast and the Misty Ocean its south coast, which the Gulf of Sora cuts into. It covers about 40,000 km² and has nearly four million people.

The capital, Almaren, stands on the River Merel a few kilometres from Lake Ormo. Almost half the people live on the coast, in port towns such as Calvera, Tessa and Port Sora. This map shows where Varenia is; the next two pages show its relief and its rivers.

:::figure{resource="locator" slot="map"}
::alt[Locator map painted as a physical map: Varenia, washed in gold, on the south coast of a continent between Ostelia to the north, Brunavia to the east, the Lira Sea to the west and the Misty Ocean to the south.]
::label[Varenia]{at="varenia"}
::label[Ostelia]{at="ostelia"}
::label[Brunavia]{at="brunavia"}
::label[Lira Sea]{at="lira"}
::label[Misty Ocean]{at="ocean"}
::label[Almaren]{at="almaren"}
:::

:::frame{slot="key" title="Key"}
:swatch{color="country"} Varenia \\
:swatch{color="land"} Other countries \\
:swatch{color="sea"} Sea and ocean \\
:swatch{color="border"} Border \\
:swatch{color="ink"} Capital
:::

:::frame{slot="tasks" title="Activities"}
1. Which countries share a border with Varenia? On which side is each one?
2. Which sea washes the west coast? Which ocean washes the south coast?
3. Find the capital. Is it on the coast or inland?
:::
::::

::::page{template="spread" spread unit="Plate 2 · Relief and rivers"}
# The relief and rivers of Varenia

The Albar Range crosses the west of the country from south-west to north-east. It is the highest range in Varenia: Albar Peak reaches 2,565 m. In the east rise the Grey Hills, lower and more rounded. Between the two lies the Ormo Plateau, about 600 m above the sea.

The rivers rise in the mountains and run down to the sea. The Sela flows west and reaches the sea at Calvera. The Duna, short and fast, runs south. The Merel, the longest, passes through Lake Ormo and flows into the Gulf of Sora. The line A–B marks the section on Plate 3.

:::figure{resource="relief" slot="map"}
::alt[Physical map of Varenia painted in height tints from green lowlands to brown peaks, with the Albar Range, the Grey Hills, the Ormo Plateau, the rivers Sela, Duna and Merel, Lake Ormo and the line of section A–B.]
::label[Misty Ocean]{at="ocean"}
::label[Lira Sea]{at="lira"}
::label[Gulf of Sora]{at="gulf"}
::label[Nema Island]{at="nema"}
::label[Albar Range]{at="albar-range"}
::label[Grey Hills]{at="gris-range"}
::label[Ormo Plateau]{at="plateau"}
::label[Calvera Plain]{at="plain"}
::label[River Sela]{at="sela"}
::label[River Duna]{at="duna"}
::label[River Merel]{at="merel"}
::label[Lake Ormo]{at="ormo"}
::label[Almaren]{at="almaren"}
::label[Calvera]{at="calvera"}
::label[Tessa]{at="tessa"}
::label[Port Sora]{at="sora"}
::label[Brena]{at="brena"}
::label[Albar Peak \\ 2,565 m]{at="albar-peak"}
::label[Grey Peak \\ 1,274 m]{at="gris-peak"}
::label[Ostelia]{at="ostelia"}
::label[Brunavia]{at="brunavia"}
::label[Varenia]{at="varenia"}
::label[A]{at="a"}
::label[B]{at="b"}
::label[0]{at="scale-0"}
::label[25]{at="scale-25"}
::label[50 km]{at="scale-50"}
::label[N]{at="north"}
:::

:::frame{slot="key" title="Height"}
:swatch{color="peak"} Over 1,800 m \\
:swatch{color="mount"} 1,000 to 1,800 m \\
:swatch{color="upland"} 500 to 1,000 m \\
:swatch{color="hill"} 200 to 500 m \\
:swatch{color="low"} 0 to 200 m \\
:swatch{color="sea"} Sea
:::

:::frame{slot="tasks" title="Activities"}
1. Which range is higher, the Albar Range or the Grey Hills? How can you tell from the colours?
2. Follow the River Merel from its source. Which lake does it pass through? Where does it reach the sea?
3. Use the scale to measure how far Calvera is from Almaren in a straight line.
:::
::::

::::page{template="sheet" unit="Plate 3 · A section"}
# A section through the Albar Range

A section shows the shape of the land as if it were cut along a line. This one follows the line A–B on the relief map: it starts in the hills of the north, drops into the Sela valley, climbs the Albar Range to more than 2,100 m and ends on the plain of the south coast.

The line A–B is 126 km long. To make the mountains easy to see, the vertical scale is stretched about fourteen times, so the slopes in the drawing look much steeper than they are.

:::paragraphs{style="colophon"}
Varenia was invented for this atlas. Text and maps: CC BY 4.0. The maps are paintings generated with diffusion models; borders, symbols and names are set by Postext. Set in Source Sans 3 and Source Serif 4 (SIL OFL).
:::

:::figure{resource="section" slot="map"}
::alt[Section from A to B painted as a slice of land: low hills, the Sela valley, the steep Albar Range with its brown crest above 2,100 m and the coastal plain, in the height bands of the map.]
::label[A]{at="a"}
::label[B]{at="b"}
::label[500 m]{at="m500"}
::label[1,000 m]{at="m1000"}
::label[1,500 m]{at="m1500"}
::label[2,000 m]{at="m2000"}
::label[Sela valley]{at="sela"}
::label[Albar Range]{at="crest"}
::label[Coastal plain]{at="plain"}
:::

:::frame{slot="key" title="Words to know"}
**Range:** a line of mountains whose peaks stand in a row.

**Plateau:** a high, flat stretch of land, more than 400 m above the sea.

**Valley:** low land between hills or mountains, often with a river along it.

**Plain:** low, nearly flat land, like the land along the south coast.
:::

:::frame{slot="tasks" title="Activities"}
1. About how high is the crest of the Albar Range on this section?
2. Why is the Sela valley lower than the land around it?
3. In your exercise book, draw the section of a line from Calvera to Almaren.
4. On the relief map, what colour is the land at A and at B? Does it match the section?
:::
::::
`; // content.<lang>.md: every word of the pages, maps included


// #region art: three paintings (JPEGs in assets/) under the vector furniture of a map
// Varenia is invented: its coast, ranges, rivers and lake are painted, without a letter, in the
// manner of a printed school atlas, and the two other plates are painted from the relief plate
// so their coasts agree. What a map must keep exact stays vector over the painting: borders,
// the line of section, towns, peaks, the scale and the north arrow. Every name, number and the
// N of the arrow is a ::label of the Markdown, standing at an anchor of ANCHORS. Positions are
// kilometres (x east, y south) of the country the painting shows, read off its grid.
const MAP = { locator: [177, 118], relief: [390, 160], section: [177, 100] }; // plates, in mm
const WIN = { // the km each map shows: x east, y south
  relief: { x0: 0, x1: 400, y0: 0, y1: 400 * MAP.relief[1] / MAP.relief[0] },
  locator: { x0: -330, x1: 770, y0: -520, y1: -520 + 1100 * MAP.locator[1] / MAP.locator[0] },
};
const TOWNS = [['almaren', 259, 127, 'capital'], ['calvera', 53, 66], ['tessa', 108, 142],
  ['sora', 296, 132], ['brena', 346, 92]];
const PEAKS = [['albar', 181, 54], ['gris', 325, 55]];
const PROFILE = [[92, 32], [166, 134]]; // A and B, the ends of the section
const PROFILE_TOP = 2600; // m at the head of the section
const SCALE = { x: 8, y: 157 }, NORTH = { x: 22, y: 140 }; // the scale bar and the arrow
// Borders in km, cut where they reach the painted coast: Varenia with Ostelia and with
// Brunavia on the relief map, and those two with the border of Ostelia and Brunavia.
const BORDERS = {
  relief: [[[59, 9], [80, 6], [128, 10], [172, 18], [214, 12], [256, 24], [298, 22], [376, 44]],
    [[376, 44], [372, 76], [380, 104], [368, 132], [371, 144]]],
  locator: [[[59, 9], [80, 6], [128, 10], [172, 18], [214, 12], [256, 24], [298, 22], [376, 44]],
    [[376, 44], [372, 76], [380, 104], [368, 132], [371, 144]],
    [[376, 44], [392, -40], [386, -132]], [[396, -222], [420, -330], [404, -520]]],
};
const r1 = (n) => Math.round(n * 10) / 10;
const svg = (w, h, body) => `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 ${w} ${h}" `
  + `width="${w * 10}" height="${h * 10}">${body}</svg>`;
const line = (d, id, width, more = '') => `<path d="${d}" fill="none" stroke="${palette[id]}" `
  + `stroke-width="${width}" stroke-linecap="round" stroke-linejoin="round"${more}/>`;
// A painting as a data URL: an SVG drawn as an image cannot fetch anything itself.
async function dataUrl(url) {
  const res = await fetch(url);
  if (!res.ok) throw new Error(`Painting not found (${res.status}): ${url}`);
  const bytes = new Uint8Array(await res.arrayBuffer());
  let bin = '';
  for (let i = 0; i < bytes.length; i += 8192) {
    bin += String.fromCharCode(...bytes.subarray(i, i + 8192));
  }
  return `data:image/jpeg;base64,${btoa(bin)}`;
}
const picture = (art, w, h, x = 0) => `<image href="${art}" x="${x}" width="${w}" height="${h}" `
  + `preserveAspectRatio="none"/>`;
// A line over a painting is cased in paper so it reads on green, ochre and blue alike.
const cased = (d, id, width, dash) => line(d, 'paper', width + 0.9, ' stroke-opacity="0.55"')
  + line(d, id, width, ` stroke-dasharray="${dash}"`);
const mapPath = (s, pts) => `M${pts.map(([x, y]) => `${s.X(x)} ${s.Y(y)}`).join('L')}`;
// The window win = { x0, x1, y0, y1 } in km laid out w mm wide: X and Y turn km into mm.
const frame = (win, w) => {
  const k = w / (win.x1 - win.x0);
  return { k, X: (x) => r1((x - win.x0) * k), Y: (y) => r1((y - win.y0) * k) };
};
const plate = (x, y, w, h) => `<rect x="${x}" y="${y}" width="${w}" height="${h}" rx="1" `
  + `fill="${palette.paper}" fill-opacity="0.72"/>`;
function reliefMap([w, h], art) { // the spread: the painted relief, borders, towns, a scale
  const s = frame(WIN.relief, w);
  let out = picture(art, w, h);
  for (const run of BORDERS.relief) out += cased(mapPath(s, run), 'border', 0.7, '2.4 1.2');
  out += cased(mapPath(s, PROFILE), 'ink', 0.5, '1 1');
  const dot = (x, y, r, more = '') => `<circle cx="${s.X(x)}" cy="${s.Y(y)}" r="${r}" `
    + `fill="${palette.ink}"${more}/>`;
  const ring = ` stroke="${palette.paper}" stroke-width="0.5"`;
  for (const [x, y] of PROFILE) out += dot(x, y, 1, ring);
  for (const [, x, y, kind] of TOWNS) {
    out += kind === 'capital'
      ? `<rect x="${s.X(x) - 1.4}" y="${s.Y(y) - 1.4}" width="2.8" height="2.8" `
        + `fill="${palette.ink}"${ring}/>`
      : dot(x, y, 1.2, ring);
  }
  for (const [, x, y] of PEAKS) {
    const [px, py] = [s.X(x), s.Y(y)];
    out += `<path d="M${px - 1.5} ${py + 1.1}L${px} ${py - 1.5}L${px + 1.5} ${py + 1.1}Z" `
      + `fill="${palette.ink}"${ring}/>`;
  }
  // A scale of 50 km in the south-west sea, and the north arrow above it, each on a pale plate.
  const [sx, sy] = [s.X(SCALE.x), s.Y(SCALE.y)], step = 25 * s.k;
  out += plate(sx - 4, sy - 2.5, 2 * step + 8, 11.5);
  out += `<rect x="${sx}" y="${sy}" width="${step}" height="1.4" fill="${palette.ink}"/>`
    + `<rect x="${sx + step}" y="${sy}" width="${step}" height="1.4" fill="${palette.paper}" `
    + `stroke="${palette.ink}" stroke-width="0.3"/>`;
  const [ax, ay] = [s.X(NORTH.x), s.Y(NORTH.y)];
  out += plate(ax - 5, ay - 17, 10, 21)
    + `<path d="M${ax} ${ay - 7}L${ax + 2.6} ${ay + 1}L${ax} ${ay - 1}L${ax - 2.6} ${ay + 1}Z" `
    + `fill="${palette.ink}"/>`;
  return svg(w, h, out + `<rect x="0.15" y="0.15" width="${w - 0.3}" height="${h - 0.3}" `
    + `fill="none" stroke="${palette.ink}" stroke-width="0.3"/>`); // the neat line
}
function locatorMap([w, h], art) { // Varenia among its neighbours, its borders and its capital
  const s = frame(WIN.locator, w);
  let out = picture(art, w, h);
  for (const run of BORDERS.locator) out += cased(mapPath(s, run), 'border', 0.5, '1.6 0.8');
  const [, x, y] = TOWNS[0];
  out += `<rect x="${s.X(x) - 1.2}" y="${s.Y(y) - 1.2}" width="2.4" height="2.4" `
    + `fill="${palette.ink}" stroke="${palette.paper}" stroke-width="0.4"/>`;
  return svg(w, h, out + `<rect x="0.15" y="0.15" width="${w - 0.3}" height="${h - 0.3}" `
    + `fill="none" stroke="${palette.ink}" stroke-width="0.3"/>`);
}
// The section A–B: the painted ground cut along the line, a rule each 500 m, the two axes.
// The painting fills the plot (14 mm in, 93 mm down); its heights are read off the rules.
function profile([w, h], art) {
  const [x0, y0, y1] = [14, 3, h - 7];
  const Y = (m) => r1(y1 - m * (y1 - y0) / PROFILE_TOP);
  let out = picture(art, w - x0, y1, x0);
  for (let m = 500; m < PROFILE_TOP; m += 500) {
    out += line(`M${x0} ${Y(m)}H${w}`, 'paper', 0.3, ' stroke-opacity="0.7"')
      + line(`M${x0 - 1.4} ${Y(m)}H${x0}`, 'ink', 0.4);
  }
  return svg(w, h, out + line(`M${x0} ${y1}H${w}`, 'ink', 0.5) + line(`M${x0} ${y0 - 3}V${y1}`,
    'ink', 0.4));
}
// #endregion

// #region anchors: the points of each map where a name stands, the same in every edition
const above = { verticalAlign: 'bottom' }, below = { verticalAlign: 'top' };
const r = km(WIN.relief), l = km(WIN.locator);
const ANCHORS = {
  relief: [
    r('ocean', 172, 157, 'ocean'), r('lira', 20, 52, 'sea', { rotate: -84 }),
    r('gulf', 318, 154, 'sea', { width: 0.07 }), r('nema', 22, 100, 'island', above),
    r('albar-range', 98, 108, 'range', { rotate: -33 }),
    r('gris-range', 308, 96, 'range', { rotate: -86 }),
    r('plateau', 236, 78, 'region'), r('plain', 70, 98, 'region', { width: 0.08 }),
    r('sela', 108, 62, 'river', { rotate: -4 }), r('duna', 121, 136, 'river', { rotate: -62 }),
    r('merel', 281, 92, 'river', { rotate: -47 }), r('ormo', 254, 104, 'river', above),
    // Calvera's name goes below its dot: the River Sela runs in just above it.
    ...TOWNS.map(([id, x, y]) => (id === 'calvera' ? r(id, x, y + 2.6, 'town', below)
      : r(id, x, y - 2.6, id === 'almaren' ? 'capital' : 'town', above))),
    ...PEAKS.map(([id, x, y]) => r(`${id}-peak`, x, y + 2.4, 'peak', below)),
    r('ostelia', 300, 9, 'country'), r('brunavia', 390, 112, 'country', { rotate: -90 }),
    r('varenia', 250, 46, 'nation'),
    r('a', PROFILE[0][0], PROFILE[0][1] - 2, 'point', above),
    r('b', PROFILE[1][0], PROFILE[1][1] + 2, 'point', below),
    r('scale-0', SCALE.x, SCALE.y + 3, 'tick', below),
    r('scale-25', SCALE.x + 25, SCALE.y + 3, 'tick', below),
    r('scale-50', SCALE.x + 50, SCALE.y + 3, 'tick', below),
    r('north', NORTH.x, NORTH.y - 8, 'point', above),
  ],
  locator: [
    l('varenia', 205, 80, 'nation'), l('ostelia', 150, -100, 'country'),
    l('brunavia', 560, -120, 'country'), l('lira', 210, -250, 'sea', { rotate: 20 }),
    l('ocean', -180, -40, 'ocean', { width: 0.2 }), l('almaren', 259, 127 + 22, 'capital', below),
  ],
  // The section: fractions of the drawing, whose plot starts 14 mm in and runs 3 to 51 mm down.
  section: (() => {
    const [w, h] = MAP.section, x = (u) => (14 + u * (w - 14)) / w;
    const y = (m) => (h - 7 - m * (h - 10) / PROFILE_TOP) / h;
    return [
      { id: 'a', x: x(0), y: (h - 5.5) / h, style: 'point', ...below },
      { id: 'b', x: x(0.98), y: (h - 5.5) / h, style: 'point', ...below },
      ...[500, 1000, 1500, 2000].map((m) => ({ id: `m${m}`, x: 7 / w, y: y(m), style: 'tick' })),
      { id: 'sela', x: x(0.3), y: y(380), style: 'region' },
      { id: 'crest', x: x(0.47), y: y(2260), style: 'range', ...above },
      { id: 'plain', x: x(0.82), y: y(430), style: 'region' },
    ];
  })(),
};
// #endregion

// #region resources: three paintings under vector furniture and their anchors; no words
// A resource has no alt text, caption or note here: each edition's `:::figure` says its own.
const PAINTINGS = { // each plate's painting, a file in assets/, named by its width in pixels
  locator: asset('locator-1776.jpg'), relief: asset('relief-1984.jpg'),
  section: asset('section-1760.jpg') };
const drawings = { locator: locatorMap, relief: reliefMap, section: profile };
const resources = Object.entries(MAP).map(([id, [w, h]]) => ({ id, typeId: 'map', kind: 'svg',
  createdAt: 0, updatedAt: 0, svg: { fileId: `${id}.svg`, width: w * 10, height: h * 10 },
  anchors: ANCHORS[id] }));
for (const [id, draw] of Object.entries(drawings)) {
  await loadSvg(`${id}.svg`, draw(MAP[id], await dataUrl(PAINTINGS[id])));
}
// #endregion

// ─── 3 · Fonts ──────────────────────────────────────────────────────────────
const FONTS = { // every face the pages use, loaded before the build
  'Source Sans 3': ['400', '400i', '600', '700'], // text, boxes and map labels
  'Source Serif 4': ['700'], // the sheets' titles
  'Noto Naskh Arabic': ['400', '700'], // the Arabic text and boxes
  'Noto Kufi Arabic': ['500', '700'], // the Arabic titles and map labels
};

// ─── 4 · Build & show ───────────────────────────────────────────────────────
await loadFonts(FONTS, markdown);
await loadArabicFonts(FONTS, markdown + JSON.stringify(resources));
const doc = await withLoadedFonts(() => buildDocument({ markdown, resources }, config),
  { ...kitFonts(FONTS), text: markdown });
showBook(doc, { title: t({ es: 'Atlas escolar de Varenia', en: 'A school atlas of Varenia',
  ar: 'أطلس فارينيا المدرسي' }) });

// ─── Kit ── helpers shared by every Cookbook recipe · postext.dev/cookbook ─────

// ─── Kit · core v1 ── the same in every recipe · postext.dev/cookbook
function mm(value) { return { value, unit: 'mm' }; }
function pt(value) { return { value, unit: 'pt' }; }
function em(value) { return { value, unit: 'em' }; }
/** The sample language's string: t({ en: 'Figure', es: 'Figura' }). */
function t(strings) { return strings[LANG] ?? Object.values(strings)[0]; }
/** A file in this recipe's assets folder, served from the Postext repo by jsDelivr. */
function asset(file) { return `https://cdn.jsdelivr.net/gh/drnachio/postext@main/cookbook/${RECIPE}/assets/${file}`; }

// ─── Kit · fonts v3 ── the same in every recipe · postext.dev/cookbook
// Postext loads the faces a config asks for before layout (prepareFonts,
// buildDocumentWithFonts) and asks the kit for the files: Fontsource's, the
// files the PDF embeds too.

/** The options of buildDocumentWithFonts / prepareFonts / withLoadedFonts:
 *  the Fontsource resolver, and the faces of FONTS loaded with the ones the
 *  config names. FONTS = { 'Family Name': ['400', '400i', '700'] }. */
function kitFonts(FONTS = {}) {
  const faces = Object.entries(FONTS).flatMap(([family, specs]) => specs.map((spec) =>
    ({ family, weight: parseInt(spec, 10), style: spec.endsWith('i') ? 'italic' : 'normal' })));
  return { resolve: fontsourceResolver, faces };
}

/** A face's Fontsource files, in a fixed order: latin, then latin-ext and greek
 *  when `text` needs them and the family ships them (kitSubsetsFor), each with
 *  its unicode-range. Null for a weight or slant Fontsource does not ship. */
async function fontsourceResolver(family, weight, style, { text = '' } = {}) {
  const id = fontsourceId(family);
  const meta = await fontsourceMeta(family);
  if (meta && !(meta.weights.includes(weight) && meta.styles.includes(style))) return null;
  kitStatus('Loading fonts…');
  const at = await fontsourceAt(id);
  return ['latin', ...kitSubsetsFor(text, meta)].map((subset) => ({
    source: `${at}files/${id}-${subset}-${weight}-${style}.woff2`,
    unicodeRange: kitRanges()[subset],
  }));
}

/** The unicode-range of each Fontsource file the kit loads (a function: the
 *  kit is inlined after the pen's code, which runs before a const would be set). */
function kitRanges() {
  return {
    latin: 'U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,'
      + 'U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD',
    'latin-ext': 'U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,'
      + 'U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF',
    greek: 'U+0370-03FF',
  };
}

/** For the cjk, arabic and comics blocks, which add their own files: the
 *  faces of `faces` = { 'Family Name': ['400', '400i', '700'] }. `text` is the sample:
 *  č ł † α χ also load latin-ext and greek files (kitSubsetsFor). With
 *  `optional`, a face Fontsource does not ship is skipped instead of failing.
 *  The files are added once all have loaded, in the order asked (latin, then
 *  latin-ext, then greek), whatever order they arrive in: the last one added
 *  wins a character two files hold. Resolves to the number of faces added. */
async function loadFonts(faces, text = '', { optional = false } = {}) {
  kitStatus('Loading fonts…');
  const ranges = kitRanges();
  const jobs = [];
  for (const [family, specs] of Object.entries(faces)) {
    const id = fontsourceId(family);
    const todo = [...new Set(specs)].map((spec) => [parseInt(spec, 10), spec.endsWith('i') ? 'italic' : 'normal'])
      .filter(([weight, style]) => !hasFace(family, weight, style)); // before any await
    const at = fontsourceAt(id);
    const meta = optional || /[^\0-ÿ]/u.test(text) ? await fontsourceMeta(family) : null;
    const subsets = ['latin', ...kitSubsetsFor(text, meta)];
    for (const [weight, style] of todo) {
      if (optional && !(meta?.weights.includes(weight) && meta.styles.includes(style))) continue;
      for (const subset of subsets) {
        const url = `${await at}files/${id}-${subset}-${weight}-${style}.woff2`;
        const face = new FontFace(family, `url(${url}) format('woff2')`,
          { weight: String(weight), style, unicodeRange: ranges[subset] });
        jobs.push(face.load().catch(() => {
          if (subset === 'latin' && !optional) throw new Error(`Fontsource has no ${family} ${weight} ${style}`);
        }));
      }
    }
  }
  const ready = await Promise.all(jobs).catch((error) => { kitFail(error); throw error; });
  return ready.filter((face) => face && document.fonts.add(face)).length;
}

/** A loaded FontFace covers this family, weight and style (fonts.check() would
 *  also say yes for families nobody declared). */
function hasFace(family, weight, style) {
  for (const face of document.fonts) {
    if (face.status !== 'loaded' || face.style !== style) continue;
    if (face.family.replace(/^["']|["']$/g, '') !== family) continue;
    const [low, high = low] = face.weight.split(' ').map(Number);
    if (weight >= low && weight <= high) return true;
  }
  return false;
}

/** The files beyond latin `text` needs that `meta`'s family ships. */
function kitSubsetsFor(text, meta) {
  return [[/[Ā-˿ᴀ-ᶿḀ-ỿ†ℓⱠ-Ɀ꜠-ꟿ]/u, 'latin-ext'], [/[Ͱ-Ͽ]/u, 'greek']]
    .filter(([re, x]) => re.test(text) && meta?.subsets?.includes(x)).map(([, x]) => x);
}

/** Fontsource's id for a family: 'Source Serif 4' → 'source-serif-4'. */
function fontsourceId(family) { return family.toLowerCase().replace(/\s+/g, '-'); }

/** A package's folder at the one version @5 names now (#766). */
function fontsourceAt(id, u = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@`) {
  return (fontsourceAt.c ??= {})[id] ??= fetch(u + '5/package.json').then((r) => r.json())
    .then((p) => p.version || 5, () => 5).then((v) => `${u}${v}/`);
}

/** The family's Fontsource metadata (weights, styles, subsets), or null. */
function fontsourceMeta(family) {
  fontsourceMeta.cache ??= new Map();
  const id = fontsourceId(family);
  if (!fontsourceMeta.cache.has(id)) {
    fontsourceMeta.cache.set(id, fetch(`https://api.fontsource.org/v1/fonts/${id}`)
      .then((res) => (res.ok ? res.json() : null), () => null));
  }
  return fontsourceMeta.cache.get(id);
}

// ─── Kit · viewer v2 ── the same in every recipe · postext.dev/cookbook
/** The pages as spreads on a dark desk, page 1 alone, then verso | recto,
 *  each painted when it scrolls near. Other options go to renderPageToCanvas. */
function showPages(docs, { title, width = 460, ...render } = {}) {
  const root = viewer(title);
  const pages = [docs].flat().flatMap((doc) =>
    doc.pages.map((page) => ({ doc, page, n: (doc.pageIndexOffset ?? 0) + page.index })));
  const spreads = [];
  let verso = null;
  for (const p of pages) {
    if (p.n % 2 === 1) { if (verso) spreads.push([verso, null]); verso = p; }
    else { spreads.push([verso, p]); verso = null; }
  }
  if (verso) spreads.push([verso, null]);
  const density = Math.min(window.devicePixelRatio || 1, 2);
  showPages.painter?.disconnect();
  const painter = new IntersectionObserver((entries) => {
    for (const { isIntersecting, target } of entries) {
      if (!isIntersecting) continue;
      painter.unobserve(target);
      const { doc, page } = target.postext;
      renderPageToCanvas(page, doc, target, { ...render, scale: (width * density) / page.width });
    }
  }, { rootMargin: '800px' });
  showPages.painter = painter;
  root.replaceChildren(...spreads.map((pair) => {
    const spread = document.createElement('div');
    spread.className = 'pt-spread';
    for (const p of pair) {
      const figure = document.createElement('figure');
      if (p) {
        const label = p.page.pageLabel || String(p.n + 1);
        const canvas = document.createElement('canvas');
        canvas.postext = p;
        canvas.style.aspectRatio = `${p.page.width} / ${p.page.height}`;
        canvas.setAttribute('role', 'img');
        canvas.setAttribute('aria-label', `Page ${label}`);
        const folio = document.createElement('figcaption');
        folio.textContent = label;
        figure.append(canvas, folio);
        painter.observe(canvas);
      } else figure.className = 'pt-blank';
      spread.append(figure);
    }
    return spread;
  }));
  kitStatus(`${pages.length} ${pages.length === 1 ? 'page' : 'pages'}`);
  document.documentElement.dataset.postext = 'ready';
  return pages.length;
}

/** The desk, the bar and the error reporting, created once. */
function viewer(title) {
  if (!document.getElementById('pt-kit')) {
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit">
      :root { color-scheme: dark; }
      body { margin: 0; background: #0e1014; color: #b9bcc4; font: 13px/1.45 system-ui, sans-serif; }
      #pt-bar { position: sticky; top: 0; z-index: 1; display: flex; flex-wrap: wrap; align-items: center;
        gap: 6px 16px; padding: 10px 16px; background: rgb(14 16 20 / .92); backdrop-filter: blur(6px);
        border-bottom: 1px solid #23262d; }
      #pt-bar strong { color: #f4f1ea; font-weight: 600; }
      #pt-actions { display: flex; gap: 12px; margin-left: auto; }
      #pt-actions a, #pt-actions button { color: #d8a21a; font: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
      #pages { display: grid; justify-items: center; gap: 48px; padding: 32px 16px 72px; }
      .pt-spread { display: flex; }
      .pt-spread figure { margin: 0; width: min(460px, 44vw); }
      .pt-spread canvas { display: block; width: 100%; background: #fff;
        box-shadow: 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figure:first-child canvas { box-shadow: inset -14px 0 14px -14px rgb(0 0 0 / .18), 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figcaption { margin-top: 10px; text-align: center; font: 600 10px/1 system-ui, sans-serif;
        letter-spacing: .18em; text-transform: uppercase; color: #6c7079; }
      .pt-blank { visibility: hidden; }
      @media (max-width: 760px) {
        .pt-spread { flex-direction: column; gap: 32px; }
        .pt-spread figure { width: min(460px, 92vw); }
        .pt-blank { display: none; }
      }
    </style>`);
    document.body.insertAdjacentHTML('afterbegin',
      '<header id="pt-bar"><strong id="pt-title"></strong><span id="pt-status" role="status"></span><span id="pt-actions"></span></header>');
    document.getElementById('pt-title').textContent = document.title || 'Postext';
    addEventListener('error', (event) => kitFail(event.error ?? event.message));
    addEventListener('unhandledrejection', (event) => kitFail(event.reason));
  }
  if (title) document.getElementById('pt-title').textContent = title;
  return document.getElementById('pages')
    ?? document.body.appendChild(Object.assign(document.createElement('main'), { id: 'pages' }));
}

function kitStatus(text) {
  viewer();
  document.getElementById('pt-status').textContent = text;
}

function kitFail(error) {
  document.documentElement.dataset.postext = 'error';
  kitStatus(`Error: ${error?.message ?? error}`);
}

// ─── Kit · images v3 ── recipes with pictures · postext.dev/cookbook
/** Registers a photo or PNG for the canvas and keeps its bytes for the PDF.
 *  fetch → ImageBitmap never taints the canvas (a plain cross-origin <img> would). */
async function loadImage(fileId, url) {
  const res = await fetch(url);
  if (!res.ok) throw new Error(`Image not found (${res.status}): ${url}`);
  const bytes = new Uint8Array(await res.arrayBuffer());
  registerResourceImage(fileId, await createImageBitmap(new Blob([bytes])));
  (loadImage.bytes ??= new Map()).set(fileId, bytes);
}

/** Registers SVG markup as a vector image, its fonts inside (inlineSvgFonts, ≥ 1.25).
 *  `options` go to registerResourceImage: { singleInk: true } tints it on the canvas. */
async function loadSvg(fileId, svg, options) {
  if (typeof inlineSvgFonts === 'function') svg = await inlineSvgFonts(svg, svgFaces);
  const img = new Image();
  img.src = `data:image/svg+xml;charset=utf-8,${encodeURIComponent(svg)}`;
  await img.decode();
  registerResourceImage(fileId, img, options);
  (loadImage.bytes ??= new Map()).set(fileId, new TextEncoder().encode(svg));
}

/** A face's Fontsource files: nearest weight; latin + what the SVG sets. */
async function svgFaces(family, weight, style, { codePoints = [] } = {}) {
  const [id, m] = [fontsourceId(family), await fontsourceMeta(family)];
  const w = m?.weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a)) ?? weight;
  const s = m?.styles.includes(style) === false ? 'normal' : style;
  return Promise.all(['latin', ...kitSubsetsFor(String.fromCodePoint(...codePoints), m)].map(async (x) => new Uint8Array(
    await (await fetch(`${await fontsourceAt(id)}files/${id}-${x}-${w}-${s}.woff2`)).arrayBuffer())));
}

/** renderToPdf({ resourceBytes: imageBytes }) */
function imageBytes(fileId) { return loadImage.bytes?.get(fileId); }

/** renderToHtml({ resourceImageUrl: imageUrl }) */
function imageUrl(fileId) {
  const bytes = imageBytes(fileId);
  if (!bytes) return undefined;
  imageUrl.urls ??= new Map();
  if (!imageUrl.urls.has(fileId)) {
    const type = /\.svg$/i.test(fileId) ? 'image/svg+xml' : /\.png$/i.test(fileId) ? 'image/png' : 'image/jpeg';
    imageUrl.urls.set(fileId, URL.createObjectURL(new Blob([bytes], { type })));
  }
  return imageUrl.urls.get(fileId);
}

// ─── Kit · arabic v2 ── Arabic-script faces · postext.dev/cookbook
// Fontsource ships an Arabic family as one file per subset and weight: the
// `arabic` file holds the letters, the harakat, the Arabic-Indic digits, the
// Arabic punctuation and the presentation forms; `latin` and `latin-ext`
// hold the rest. loadFonts loads the latin files; this block adds the arabic
// file of every Arabic family, for the canvas and for the PDF, which shapes
// the letters with HarfBuzz from the same bytes.

/** The code points of Fontsource's `arabic` subset, as its stylesheets
 *  declare them (the same unicode-range the browser picks the file by). A
 *  function, not a const: the kit is inlined after the recipe's top-level
 *  awaits, and a const read before its line throws, where a function
 *  declaration is hoisted. */
function arabicRange() {
  return 'U+0600-06FF,U+0750-077F,U+0870-088E,U+0890-0891,U+0897-08E1,U+08E3-08FF,'
    + 'U+200C-200E,U+2010-2011,U+204F,U+2E41,U+FB50-FDFF,U+FE70-FE74,U+FE76-FEFC,U+102E0-102FB,'
    + 'U+10E60-10E7E,U+10EC2-10EC4,U+10EFC-10EFF,U+1EE00-1EEFF';
}

/** Whether code point `cp` is in the arabic file. */
function inArabicRange(cp) {
  inArabicRange.ranges ??= arabicRange().split(',').map((part) => {
    const [lo, hi = lo] = part.slice(2).split('-');
    return [parseInt(lo, 16), parseInt(hi, 16)];
  });
  return inArabicRange.ranges.some(([lo, hi]) => cp >= lo && cp <= hi);
}

/** Whether Fontsource serves `family` with an `arabic` subset. Fails when
 *  the API does not answer: an Arabic face taken for a Latin one would set
 *  its letters in a system face. */
async function isArabicFamily(family) {
  const meta = await fontsourceMeta(family);
  if (!meta) throw new Error(`api.fontsource.org did not describe ${family}: reload to try again`);
  return !!meta.subsets?.includes('arabic');
}

/** The arabic file of a face. */
async function arabicFileUrl(family, weight, style) {
  const id = fontsourceId(family);
  return `${await fontsourceAt(id)}files/${id}-arabic-${weight}-${style}.woff2`;
}

/** faces = { Amiri: ['400', '700'] }, as for loadFonts, after it: the whole
 *  FONTS object may be passed, its families without an arabic subset are
 *  left alone. Adds the arabic file of every listed weight of each Arabic
 *  family (the latin files come from loadFonts) and loads it. `text` is
 *  the sample: fails when it holds an Arabic-script character the arabic
 *  file does not cover. List every weight the pages set in Arabic: a weight
 *  left to the engine's later round gets the latin file only, and its Arabic letters
 *  fall back to a system face. Resolves to the number of files loaded. */
async function loadArabicFonts(faces, text = '') {
  kitStatus('Loading fonts…');
  let loaded = 0;
  try {
    const outside = [...new Set(text)].filter((ch) => /\p{Script=Arabic}/u.test(ch) && !inArabicRange(ch.codePointAt(0)));
    if (outside.length) throw new Error(`Fontsource's arabic files have no ${outside.slice(0, 12).join(' ')}`);
    for (const [family, specs] of Object.entries(faces)) {
      if (!(await isArabicFamily(family))) continue;
      for (const spec of new Set(specs)) {
        const weight = parseInt(spec, 10);
        const style = spec.endsWith('i') ? 'italic' : 'normal';
        const face = new FontFace(family, `url(${await arabicFileUrl(family, weight, style)}) format('woff2')`,
          { weight: String(weight), style, unicodeRange: arabicRange() });
        document.fonts.add(await face.load().catch(() => {
          throw new Error(`Fontsource has no arabic file for ${family} ${weight} ${style}`);
        }));
        loaded++;
      }
    }
  } catch (error) {
    kitFail(error);
    throw error;
  }
  return loaded;
}

/** The PDF font provider for recipes with Arabic faces: a family with an
 *  arabic subset gets its arabic file when its pages set Arabic letters
 *  (`request.codePoints`), then its latin file, and its latin-ext file for
 *  the letters beyond latin (transliteration: ā ḥ ʿ), each marked with its
 *  unicode-range and its place in the order the screen added them (latin
 *  and latin-ext by loadFonts, then arabic): the arabic file also has a
 *  space and brackets, which the browser takes from latin, the file whose
 *  range holds them, and postext-pdf follows it. Any other family goes to
 *  fontsourceProvider (the "pdf" block). */
async function arabicPdfProvider(family, weight, style, request) {
  if (!(await isArabicFamily(family))) return fontsourceProvider(family, weight, style, request);
  const meta = await fontsourceMeta(family);
  const weights = meta.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && !meta.styles.includes('italic') ? 'normal' : style;
  const wanted = [...(request?.codePoints ?? [])];
  const id = fontsourceId(family);
  const subsets = !wanted.length || wanted.some(inArabicRange) ? ['arabic', 'latin'] : ['latin'];
  if (meta.subsets.includes('latin-ext') && wanted.some((cp) => /[Ā-˿Ḁ-ỿ]/u.test(String.fromCodePoint(cp)))) {
    subsets.push('latin-ext');
  }
  const at = await fontsourceAt(id);
  return Promise.all(subsets.map(async (subset) => {
    const url = `${at}files/${id}-${subset}-${w}-${s}.woff2`;
    const res = await fetch(url);
    if (!res.ok) throw new Error(`Fontsource file ${url} (${res.status})`);
    const bytes = await decompressWoff2(new Uint8Array(await res.arrayBuffer()));
    return Object.assign(bytes, { unicodeRange: subset === 'arabic' ? arabicRange() : kitRanges()[subset],
      order: ['latin', 'latin-ext', 'greek', 'arabic'].indexOf(subset) });
  }));
}

// ─── Kit · book v1 ── books bound on either edge · postext.dev/cookbook
// A book bound on the right (Arabic, Hebrew or Persian text, vertical
// Chinese, or page.binding 'right') opens from what a Latin reader calls
// the back: page 1 lies alone on the left of the spine, then [3 | 2].

/** showPages for a book bound on either edge. A right-bound book (the
 *  document says so: doc.binding is 'right' for page.binding 'right', for
 *  text that runs right to left and for vertical text, when the binding is
 *  left to 'auto') lies on the desk as it opens: page 1 alone on the left
 *  of the spine, then [3 | 2], the spine shade on each page's inner edge.
 *  `binding` ('left' | 'right') overrides the document's. */
function showBook(docs, { binding, ...options } = {}) {
  const count = showPages(docs, options);
  const right = (binding ?? [docs].flat()[0]?.binding) === 'right';
  if (!document.getElementById('pt-kit-book')) {
    // The pages keep direction ltr, as in a left-bound book: a canvas takes
    // the direction its element inherits, and under the spread's rtl a run
    // painted for an ltr canvas would end where the engine starts it.
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit-book">
      .pt-spread[dir="rtl"] canvas { direction: ltr; }
      .pt-spread[dir="rtl"] figure:first-child canvas { box-shadow: inset 14px 0 14px -14px rgb(0 0 0 / .18),
        0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
    </style>`);
  }
  // Each pair stays [verso, recto] in the page; right to left, the verso
  // sits on the right. Phones stack the pages in reading order either way.
  for (const spread of document.querySelectorAll('#pages > .pt-spread')) spread.dir = right ? 'rtl' : 'ltr';
  document.getElementById('pages').dataset.binding = right ? 'right' : 'left';
  return count;
}

// ─── /Kit ───────────────────────────────────────────────────────────────────────
```

## Variantes

### Nommez un lieu sans ancre

Une étiquette peut se poser sur un point donné en pourcentages de l’image, avec son propre style.

```diff
 :::figure{resource="relief" slot="map"}
+::label[Nema Light]{at="7% 68%" style="town"}
 ::label[Misty Ocean]{at="ocean"}
```

### Numérotez les cartes et légendez-les

Donnez au type de carte un compteur et un préfixe, et à chaque ressource une légende : voyez [la planche d’atlas aux cartes numérotées](https://postext.dev/fr/cookbook/atlas-map-sheet.md), qui pose les légendes de ses cartes sur une barre bleue.

## Erreurs fréquentes

- **Avertissement de mise en page: Étiquette sur une ancre inconnue** (`labelAnchorUnknown`). Une ::label d'une :::figure désigne avec at= une ancre que la ressource de la figure n'a pas. L'étiquette n'est pas dessinée sur l'image ; l'EPUB recomposable la liste toujours et le texte alternatif de l'image la cite. Solution: Corrigez l'id de l'ancre dans at= (l'avertissement liste les ancres de la ressource), ajoutez l'ancre à la ressource ou placez l'étiquette avec at="x% y%". ([Documentation](https://postext.dev/fr/docs/composed-pages.md#labelanchorunknown))
- **Avertissement de mise en page: Ancre sans étiquette** (`anchorUnlabelled`). Une ancre de la ressource d'une figure porte un style d'étiquette et aucune ::label de la figure ne s'y trouve dans cette langue : il manque à cette édition le mot pour lequel la carte a de la place. C'est une note, pas une erreur ; les ancres sans style (celles des personnages d'une BD) ne sont pas signalées. Solution: Écrivez l'étiquette dans le Markdown de cette langue (::label[…]{at="ancre"}), ou retirez le style de l'ancre si cette édition se passe du mot. ([Documentation](https://postext.dev/fr/docs/composed-pages.md#anchorunlabelled))

- Le texte alternatif de chaque carte se trouve dans le Markdown, dans une ligne `::alt[…]` à l’intérieur de son `:::figure`, une par édition. Une figure qui n’en donne pas garde l’`altText` de la ressource ; `script.js` ne contient aucun mot de la page.
- Les ancres et les symboles vectoriels (frontières, villes, sommets, ligne de coupe) sont placés à des kilomètres lus sur la peinture. Si l’on repeint une carte, ses côtes, ses fleuves et ses crêtes bougent : posez la grille sur la nouvelle image et relisez-les, sinon un nom tombera dans la mer.
- Sur une page de droite à gauche, les blocs suivent la zone de contenu en miroir, mais le décor du modèle reste en place : placez le surtitre selon l’édition, comme le fait `kicker`.
- Un bloc sur deux colonnes peut couper un paragraphe une ligne avant sa fin et laisser cette ligne en tête de la seconde colonne. Relisez les colonnes de chaque édition et faites passer une phrase d’un paragraphe au suivant quand cela arrive.

## Crédits

- Recette: Ignacio Ferro ([@drnachio](https://github.com/drnachio))
- Images: The locator map of Varenia and its neighbours, painted as a physical map with a golden wash over Varenia.: Generated With Diffusion Models, original
- Images: The relief map of Varenia across a double page: hypsometric tints, hill shading, coastal shelf, rivers and a lake.: Generated With Diffusion Models, original
- Images: The section from A to B painted as a slice of land cut along the line, in the height bands of the map.: Generated With Diffusion Models, original
- Caractères: Source Sans 3 (OFL-1.1), Source Serif 4 (OFL-1.1), Noto Naskh Arabic (OFL-1.1), Noto Kufi Arabic (OFL-1.1)
- Code: MIT · Contenu d’exemple: CC-BY-4.0

## Recettes liées

- [Nº 067 · Planche d’atlas : cartes numérotées et vue générale tournée](https://postext.dev/fr/cookbook/atlas-map-sheet.md): Des cartes à numérotation propre et légende sur une barre bleue, une clé de pastilles aux couleurs des cartes, et une carte marine tournée en page 3. · Niveau 3 (Avancé) · Manuels, guides et ouvrages de référence
- [Nº 106 · Un rapport bilingue arabe–anglais](https://postext.dev/fr/cookbook/bilingual-arabic-english-report.md): Un rapport annuel en arabe avec l’anglais en regard : {dir=ltr} sur chaque bloc anglais, :ltr[…] pour les noms latins, un tableau de gauche à droite. · Niveau 2 (Intermédiaire) · Rapports
- [Nº 009 · Des figures qui flottent là où vous les citez](https://postext.dev/fr/cookbook/figures-float-where-cited.md): Chapitre en deux colonnes, sept figures numérotées : six flottent du premier :ref à la première place permise ; une reste où ::resource la pose. · Niveau 3 (Avancé) · Manuels scolaires