Wrapping and Alignment

Wrapping

Pass maxWidth and text wraps to fit:

page.drawText(paragraph, {
  font,
  x: 40,
  y: 700,
  size: 11,
  maxWidth: 360,
  lineHeight: 15,
});

Without maxWidth, only hard line breaks (\n, \r, \f, \v) split lines.

Alignment

align controls how wrapped lines sit within maxWidth:

page.drawText(paragraph, {
  font,
  x: 40,
  y: 700,
  maxWidth: 360,
  align: 'justify',
});

Value	Behaviour
left	Default. Lines start at x.
center	Centred within maxWidth.
right	Flush to x + maxWidth.
justify	Stretched to fill maxWidth.

justify stretches every line except the last of each paragraph, matching CSS text-align: justify. See the live demo.

Without maxWidth, center and right align against the widest line, and justify falls back to left.

Word boundaries

Break points come from Intl.Segmenter, so text in scripts that do not separate words with spaces — Khmer, Thai, Lao, Japanese — wraps and justifies at real word boundaries rather than only at spaces:

page.drawText('សួស្តីពិភពលោក សូមស្វាគមន៍មកកាន់ប្រទេសកម្ពុជា', {
  font: khmer,
  maxWidth: 360,
  align: 'justify',
});

Set locale to choose a specific segmentation locale; it defaults to the runtime's.

Long words

A word wider than maxWidth is broken between graphemes, so combining marks stay attached to their base character. To let it overflow instead:

page.drawText(text, { maxWidth: 200, wordBreak: 'keep-all' });

Soft hyphens (­) act as optional break points and are never rendered.

Laying out text yourself

wrapText returns the line boxes without drawing anything — useful for measuring a block, paginating, or rendering elsewhere:

import { wrapText } from 'happypdf';

const lines = wrapText(paragraph, (t) => font.widthOfTextAtSize(t, 11), {
  maxWidth: 360,
  align: 'justify',
});

Each line is:

interface WrappedLine {
  text: string; // the line, whitespace trimmed
  runs: { text: string; x: number }[]; // pieces to draw, offset from the line start
  width: number; // natural width, before justification
  isParagraphEnd: boolean; // ends at a hard break or end of text
}

Justified lines carry one run per stretched piece; every other alignment carries a single run.

Measuring a block's height

const lines = wrapText(text, (t) => font.widthOfTextAtSize(t, size), {
  maxWidth,
});
const height = lines.length * lineHeight;