Create Documents

The library supports creating new PDF documents programmatically. This guide explains how to build PDFs from scratch.

Overview

Document creation workflow:

1. Get a PDFiumDocumentBuilder from pdfium.createDocument()
2. Load fonts with builder.loadStandardFont()
3. Add pages with builder.addPage()
4. Add content to each page
5. Call page.finalize() for each page
6. Save with builder.save()

Basic Example

import { PDFium } from '@scaryterry/pdfium';
import { promises as fs } from 'fs';

async function createSimplePDF() {
  using pdfium = await PDFium.init();
  using builder = pdfium.createDocument();

  const font = builder.loadStandardFont('Helvetica');

  {
    using page = builder.addPage(); // US Letter size (default)
    page.addText('Hello, World!', 72, 720, font, 24);
    page.finalize();
  }

  const pdfBytes = builder.save();
  await fs.writeFile('hello.pdf', pdfBytes);
}

Page Sizes

Standard Sizes

// US Letter (default)
using page = builder.addPage(); // 612 x 792 pt

// US Letter explicit
using page = builder.addPage({ width: 612, height: 792 });

// A4
using page = builder.addPage({ width: 595, height: 842 });

// A3
using page = builder.addPage({ width: 842, height: 1191 });

// US Legal
using page = builder.addPage({ width: 612, height: 1008 });

Size Reference

Format	Width (pt)	Height (pt)	Inches
US Letter	612	792	8.5 × 11
US Legal	612	1008	8.5 × 14
A4	595	842	8.27 × 11.69
A3	842	1191	11.69 × 16.54
A5	420	595	5.83 × 8.27

Custom Sizes

// 5" x 7" (inches × 72 = points)
using page = builder.addPage({ width: 360, height: 504 });

// 100mm x 150mm (mm × 2.835 = points)
using page = builder.addPage({ width: 283.5, height: 425.25 });

Landscape Orientation

// Landscape A4
using page = builder.addPage({ width: 842, height: 595 });

Standard Fonts

The 14 standard PDF fonts are available without embedding:

Sans-Serif (Helvetica)

const helvetica = builder.loadStandardFont('Helvetica');
const helveticaBold = builder.loadStandardFont('Helvetica-Bold');
const helveticaOblique = builder.loadStandardFont('Helvetica-Oblique');
const helveticaBoldOblique = builder.loadStandardFont('Helvetica-BoldOblique');

Serif (Times)

const times = builder.loadStandardFont('Times-Roman');
const timesBold = builder.loadStandardFont('Times-Bold');
const timesItalic = builder.loadStandardFont('Times-Italic');
const timesBoldItalic = builder.loadStandardFont('Times-BoldItalic');

Monospace (Courier)

const courier = builder.loadStandardFont('Courier');
const courierBold = builder.loadStandardFont('Courier-Bold');
const courierOblique = builder.loadStandardFont('Courier-Oblique');
const courierBoldOblique = builder.loadStandardFont('Courier-BoldOblique');

Symbols

const symbol = builder.loadStandardFont('Symbol');
const zapf = builder.loadStandardFont('ZapfDingbats');

Adding Text

Basic Text

const font = builder.loadStandardFont('Helvetica');

// Position is (x, y) from bottom-left, y is baseline
page.addText('Hello, World!', 72, 720, font, 24);

Coordinate System

• Origin (0, 0) is at the bottom-left of the page
• X increases to the right
• Y increases upward
• Text is positioned at its baseline

// One inch from left edge, one inch from top on US Letter
page.addText('Top-left area', 72, 792 - 72, font, 12);

// Centred horizontally (approximate)
const text = 'Centred Text';
const approxWidth = text.length * 7; // ~7pt per char for 12pt font
page.addText(text, (612 - approxWidth) / 2, 400, font, 12);

Multiple Text Blocks

const titleFont = builder.loadStandardFont('Helvetica-Bold');
const bodyFont = builder.loadStandardFont('Helvetica');

page.addText('Document Title', 72, 720, titleFont, 24);
page.addText('Subtitle here', 72, 690, bodyFont, 14);
page.addText('Body text content...', 72, 650, bodyFont, 12);

Adding Shapes

Rectangles

// Filled rectangle
page.addRect(72, 700, 200, 50, {
  fill: { r: 200, g: 220, b: 255, a: 255 },
});

// Border only
page.addRect(72, 600, 200, 50, {
  stroke: { r: 0, g: 0, b: 0, a: 255 },
  strokeWidth: 1,
});

// Fill and border
page.addRect(72, 500, 200, 50, {
  fill: { r: 255, g: 255, b: 200, a: 255 },
  stroke: { r: 0, g: 0, b: 0, a: 255 },
  strokeWidth: 2,
});

Lines

// Horizontal line (thin rectangle)
page.addRect(72, 650, 468, 1, {
  fill: { r: 0, g: 0, b: 0, a: 255 },
});

// Thicker line
page.addRect(72, 600, 468, 3, {
  fill: { r: 100, g: 100, b: 100, a: 255 },
});

Paths (Polygons)

// Triangle
page.addPath([
  { x: 200, y: 400 },
  { x: 300, y: 500 },
  { x: 100, y: 500 },
  { x: 200, y: 400 }, // Close path
], {
  fill: { r: 255, g: 200, b: 100, a: 255 },
  stroke: { r: 0, g: 0, b: 0, a: 255 },
  strokeWidth: 1,
});

// Diamond
page.addPath([
  { x: 400, y: 350 },
  { x: 450, y: 400 },
  { x: 400, y: 450 },
  { x: 350, y: 400 },
  { x: 400, y: 350 },
], {
  fill: { r: 100, g: 200, b: 255, a: 255 },
});

Multi-Page Documents

const font = builder.loadStandardFont('Helvetica');
const boldFont = builder.loadStandardFont('Helvetica-Bold');

for (let i = 0; i < 5; i++) {
  using page = builder.addPage();

  page.addText(`Page ${i + 1}`, 72, 720, boldFont, 18);
  page.addText(`Content for page ${i + 1}...`, 72, 680, font, 12);

  // Page number at bottom
  page.addText(
    `${i + 1} of 5`,
    306, // Centred on US Letter
    36,
    font,
    10
  );

  page.finalize();
}

Saving Options

Basic Save

const bytes = builder.save();

Specify PDF Version

// PDF 1.7
const bytes = builder.save({ version: 17 });

// PDF 2.0
const bytes = builder.save({ version: 20 });

Complete Example: Invoice

import { PDFium } from '@scaryterry/pdfium';
import { promises as fs } from 'fs';

async function createInvoice() {
  using pdfium = await PDFium.init();
  using builder = pdfium.createDocument();

  const regular = builder.loadStandardFont('Helvetica');
  const bold = builder.loadStandardFont('Helvetica-Bold');

  {
    using page = builder.addPage();

    // Header background
    page.addRect(0, 742, 612, 50, {
      fill: { r: 50, g: 100, b: 150, a: 255 },
    });

    // Header text
    page.addText('INVOICE', 72, 760, bold, 28);

    // Company info (right side)
    page.addText('Acme Corporation', 400, 720, bold, 12);
    page.addText('123 Business Street', 400, 705, regular, 10);
    page.addText('London, UK EC1A 1BB', 400, 690, regular, 10);

    // Invoice details
    page.addText('Invoice #: INV-2024-001', 72, 680, regular, 10);
    page.addText('Date: 15 January 2024', 72, 665, regular, 10);
    page.addText('Due: 15 February 2024', 72, 650, regular, 10);

    // Bill to
    page.addText('Bill To:', 72, 610, bold, 11);
    page.addText('Customer Name', 72, 595, regular, 10);
    page.addText('456 Customer Ave', 72, 580, regular, 10);
    page.addText('Manchester, UK M1 1AA', 72, 565, regular, 10);

    // Table header
    const tableTop = 520;
    page.addRect(72, tableTop - 20, 468, 25, {
      fill: { r: 240, g: 240, b: 240, a: 255 },
    });
    page.addText('Description', 80, tableTop - 10, bold, 10);
    page.addText('Qty', 350, tableTop - 10, bold, 10);
    page.addText('Price', 400, tableTop - 10, bold, 10);
    page.addText('Total', 480, tableTop - 10, bold, 10);

    // Table rows
    const items = [
      { desc: 'Professional Services', qty: 10, price: 150 },
      { desc: 'Software Licence', qty: 1, price: 500 },
      { desc: 'Support Package', qty: 1, price: 200 },
    ];

    let y = tableTop - 45;
    let subtotal = 0;

    for (const item of items) {
      const total = item.qty * item.price;
      subtotal += total;

      page.addText(item.desc, 80, y, regular, 10);
      page.addText(String(item.qty), 355, y, regular, 10);
      page.addText(`$${item.price.toFixed(2)}`, 395, y, regular, 10);
      page.addText(`$${total.toFixed(2)}`, 475, y, regular, 10);

      y -= 20;
    }

    // Separator line
    page.addRect(72, y - 10, 468, 1, {
      fill: { r: 0, g: 0, b: 0, a: 255 },
    });

    // Totals
    y -= 30;
    const tax = subtotal * 0.2;
    const grandTotal = subtotal + tax;

    page.addText('Subtotal:', 380, y, regular, 10);
    page.addText(`$${subtotal.toFixed(2)}`, 475, y, regular, 10);

    y -= 18;
    page.addText('VAT (20%):', 380, y, regular, 10);
    page.addText(`$${tax.toFixed(2)}`, 475, y, regular, 10);

    y -= 18;
    page.addRect(370, y - 5, 170, 25, {
      fill: { r: 50, g: 100, b: 150, a: 255 },
    });
    page.addText('TOTAL:', 380, y + 5, bold, 11);
    page.addText(`$${grandTotal.toFixed(2)}`, 470, y + 5, bold, 11);

    // Footer
    page.addText('Payment terms: Net 30', 72, 100, regular, 9);
    page.addText('Thank you for your business!', 72, 85, regular, 9);

    page.finalize();
  }

  const bytes = builder.save({ version: 17 });
  await fs.writeFile('invoice.pdf', bytes);
  console.log('Invoice created successfully');
}

createInvoice();

See Also

• PDFiumDocumentBuilder — API reference
• PDFiumPageBuilder — Page content API
• Add Text Guide — Text positioning details
• Add Shapes Guide — Shape styling guide