generatePdfWatermarkStream static method

String generatePdfWatermarkStream(
  1. String text, {
  2. double opacity = 0.3,
  3. double fontSize = 42,
})

Generates a PDF watermark content stream for embedding in PDF pages.

Returns a PDF content stream string that renders a diagonal watermark.

Implementation

static String generatePdfWatermarkStream(
  String text, {
  double opacity = 0.3,
  double fontSize = 42,
}) {
  final gray = (0.85).toStringAsFixed(2);
  return '''
q
/F1 ${fontSize.toStringAsFixed(0)} Tf
$gray $gray $gray rg
0.7071 -0.7071 0.7071 0.7071 150 400 cm
BT
0 0 Td
(${_escapePdfText(text.toUpperCase())}) Tj
ET
Q''';
}