Form XObjects

A form XObject stores drawing commands once and can be placed repeatedly. This reduces repeated content in a PDF and is also used when embedding images or PDF pages.

var form = pdfWriter.createFormXObject(0, 0, 200, 100);
form.getContentContext().drawRectangle(0, 0, 200, 100, { type: "fill" });
pdfWriter.endFormXObject(form);

pdfWriter
  .startPageContentContext(page)
  .q()
  .cm(1, 0, 0, 1, 72, 600)
  .doXObject(form)
  .Q();

Finish a form with endFormXObject before placing it. The id property is its PDF object ID.