...the requirement is to be able to print the final document onto paper, with precise control over the placement of elements. The document will be printed double sided, and elements on opposite sides of the sheet need to line up to within a millimetre or so. I know that PDF will meet that requirement, but I don't know of any other format that will

Yes, that strict print requirement precludes using HTML.

You looked into Cairo and SVG as intermediate formats but not any of the venerable print document formats? I guess it's an indication of how much the web has eclipsed print that its document formats are being lost to obscurity:

FormatModules
PostScriptCPAN (287 found)
TeXCPAN (156 found)
ODF (Open Document Format)CPAN (28 found)
DVI (Device independent)CPAN (14 found)

PostScript and TeX go way back, while ODF is new.

In reply to Re^3: Generating multi page PDF with bitmap images, vector graphics and text. by tod222
in thread Generating multi page PDF with bitmap images, vector graphics and text. by chrestomanci

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