@cantoo/pdf-lib
Version:
Create and modify PDF files with JavaScript
100 lines • 4.19 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
const tslib_1 = require("tslib");
const standard_fonts_1 = require("@pdf-lib/standard-fonts");
const PDFHexString_1 = tslib_1.__importDefault(require("../objects/PDFHexString"));
const utils_1 = require("../../utils");
/**
* A note of thanks to the developers of https://github.com/foliojs/pdfkit, as
* this class borrows from:
* https://github.com/foliojs/pdfkit/blob/f91bdd61c164a72ea06be1a43dc0a412afc3925f/lib/font/afm.coffee
*/
class StandardFontEmbedder {
constructor(fontName, customName) {
// prettier-ignore
this.encoding = (fontName === standard_fonts_1.FontNames.ZapfDingbats ? standard_fonts_1.Encodings.ZapfDingbats
: fontName === standard_fonts_1.FontNames.Symbol ? standard_fonts_1.Encodings.Symbol
: standard_fonts_1.Encodings.WinAnsi);
this.font = standard_fonts_1.Font.load(fontName);
this.fontName = this.font.FontName;
this.customName = customName;
}
/**
* Encode the JavaScript string into this font. (JavaScript encodes strings in
* Unicode, but standard fonts use either WinAnsi, ZapfDingbats, or Symbol
* encodings)
*/
encodeText(text) {
const glyphs = this.encodeTextAsGlyphs(text);
const hexCodes = new Array(glyphs.length);
for (let idx = 0, len = glyphs.length; idx < len; idx++) {
hexCodes[idx] = (0, utils_1.toHexString)(glyphs[idx].code);
}
return PDFHexString_1.default.of(hexCodes.join(''));
}
widthOfTextAtSize(text, size) {
const glyphs = this.encodeTextAsGlyphs(text);
let totalWidth = 0;
for (let idx = 0, len = glyphs.length; idx < len; idx++) {
const left = glyphs[idx].name;
const right = (glyphs[idx + 1] || {}).name;
const kernAmount = this.font.getXAxisKerningForPair(left, right) || 0;
totalWidth += this.widthOfGlyph(left) + kernAmount;
}
const scale = size / 1000;
return totalWidth * scale;
}
heightOfFontAtSize(size, options = {}) {
const { descender = true } = options;
const { Ascender, Descender, FontBBox } = this.font;
const yTop = Ascender || FontBBox[3];
const yBottom = Descender || FontBBox[1];
let height = yTop - yBottom;
if (!descender)
height += Descender || 0;
return (height / 1000) * size;
}
sizeOfFontAtHeight(height) {
const { Ascender, Descender, FontBBox } = this.font;
const yTop = Ascender || FontBBox[3];
const yBottom = Descender || FontBBox[1];
return (1000 * height) / (yTop - yBottom);
}
embedIntoContext(context, ref) {
const fontDict = context.obj({
Type: 'Font',
Subtype: 'Type1',
BaseFont: this.customName || this.fontName,
Encoding: this.encoding === standard_fonts_1.Encodings.WinAnsi ? 'WinAnsiEncoding' : undefined,
});
if (ref) {
context.assign(ref, fontDict);
return ref;
}
else {
return context.register(fontDict);
}
}
widthOfGlyph(glyphName) {
// Default to 250 if font doesn't specify a width
return this.font.getWidthOfGlyph(glyphName) || 250;
}
encodeTextAsGlyphs(text) {
const codePoints = Array.from(text);
const glyphs = new Array(codePoints.length);
for (let idx = 0, len = codePoints.length; idx < len; idx++) {
const codePoint = (0, utils_1.toCodePoint)(codePoints[idx]);
try {
glyphs[idx] = this.encoding.encodeUnicodeCodePoint(codePoint);
}
catch (error) {
// Replace non-WinAnsi characters with a placeholder
glyphs[idx] = this.encoding.encodeUnicodeCodePoint((0, utils_1.toCodePoint)('?'));
}
}
return glyphs;
}
}
StandardFontEmbedder.for = (fontName, customName) => new StandardFontEmbedder(fontName, customName);
exports.default = StandardFontEmbedder;
//# sourceMappingURL=StandardFontEmbedder.js.map