Turns a Tincture.PDF document into PDF bytes.

export/1 assembles the object graph — catalog, page tree, content streams, resources, annotations, outlines — then writes the cross-reference table and trailer.

Font embedding is a large enough concern to live on its own in Tincture.PDF.FontEmbed, which this module calls once and then treats as a set of object references. Image XObjects, the object table and the page structure are handled here.

Text is encoded according to the font it is drawn with: literal or UTF-16BE for simple fonts, glyph indices for composite ones. See Tincture.PDF.Object for the string encoding rules.

Content streams are written uncompressed. Image data carries its own filter, but page content does not, which costs file size on text-heavy documents — see the object and cross-reference stream item on the roadmap.