Advanced > Overprint: Preserve (the default; document.exportPdf
advanced.overprint) writes each overprinting fill and stroke (an object's
own, a character's, a type object's) with a graphics state of /OP true
/op true /OPM 1 (/OPM 0 in PDF/A); Discard writes none. White ones knock out
when Document Setup's Discard White Overprint is on, as in print. Mask art
never overprints. File > Print's composite PDF honours Print > Advanced >
Overprints: Preserve the same way (separations keep multiplying plates).
Each overprinting fill or stroke is drawn as a form marked to overprint
(crates/pdf/src/forms.rs); after writing, its content starts by setting the
overprinting graphics state, and the PDF/X self-check runs on the result.
The engine's "overprint is not written to PDF yet" warning and print's
"overprints print as knockouts in composite output" warning are gone.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The pdf crate's PrintSettings gains advanced {printAsBitmap,
overprints: preserve|discard|simulate, flattenerPreset} and
color.profile, all defaulting so saved print_setup values still load.
Composite output discards overprints (no /OP) or simulates them as
Overprint Preview draws them; separations keep them. A printer profile
converts composite colours with the chosen intent (a CMYK one writes
device CMYK) and separations separate with a CMYK one. The engine
flattens transparency with the preset, or renders each printed region
as one image for Print as Bitmap, before PDF or PostScript layout.
The Print dialog's Advanced and Color Management sections show them.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
