Function buildFont

packages/core/src/processor.ts:70–355

(
	ctx: FontContext,
	fontBuffers: Uint8Array[],
	config: FontBuildConfig,
)

 * Build packaged font assets and matching CSS from raw font buffers.
 */
export const buildFont = async (
	ctx: FontContext,
	fontBuffers: Uint8Array[],
	config: FontBuildConfig,
): Promise<FontBuildResult> => {
	const { glyphtContext, compressionContext } = ctx;

	const fontRefs = await glyphtContext.loadFonts(fontBuffers);
	const familyId = config.id ?? normalizeKebabCase(config.family);
	const subsets = generateSubsetData(config);
	const isVariableFont = config.type === 'variable';

	const families = sortFontsIntoFamilies(fontRefs);
	const defaultSubset = config.subsets[0];
	const requestedFormats = new Set(config.formats ?? ['woff2']);
	const exportFormats = {
		woff: requestedFormats.has('woff'),
		woff2: requestedFormats.has('woff2'),
	};

	// Determine which formats to export based on config and availability.
	const assetFormats: WebFontFormat[] = [];
	if (exportFormats.woff2) {
		assetFormats.push('woff2');
	}
	if (exportFormats.woff) {
		assetFormats.push('woff');
	}

	// Build `unicode-range` character sets.
	const includeCharacters = config.subsets.flatMap((subsetName) => {
		const def = subsets.get(subsetName);
		if (!def) return [];

		if (def.type === 'range') {
			return [{ name: subsetName, includeUnicodeRanges: def.codepoints }];
		}

		return def.slices.map((slice) => ({
			name: `${subsetName}-${slice.index}`,
			includeUnicodeRanges: slice.codepoints,
		}));
	});
	const subsetUnicodeRanges = new Map<string, string>();

	for (const [subsetName, subsetDef] of subsets) {
		if (subsetDef.type === 'range') {
			subsetUnicodeRanges.set(subsetName, subsetDef.unicodeRange);
			continue;
		}

		for (const slice of subsetDef.slices) {
			subsetUnicodeRanges.set(
				`${subsetName}-${slice.index}`,
				codepointsToRangeString(slice.codepoints),
			);
		}
	}