[NTG-pdftex] missing pages (was: pdfannot in xform)

[Martin Schröder]

On 2004-07-02 15:13:37 +0200, Heiko Oberdiek wrote:
> DEFAULT  := -1 or 0 (see below)
> Continue := Continue with empty xform object with dimension 1pt x 1pt.

I dislike the 1pt (although it's difficult to generate pdfs with
1pt² (distiller will not produce it), it's still possible).
Better: 1sp². _Nobody_ will do this intentional. :-)

> if PDFFileExists
>     if PageNumber < 1
>         \pdflastximagepages = DEFAULT
>         Warning "Invalid page number"
>         Continue
>     elsif PageNumber > \pdflastximagepages
>         \pdflastximagepages is set
>         Warning "Page number to large (out of range)
>         Continue
>     else
>         \pdflastximagepages is set
>         image is included
>     fi
> else
>     Warning "PDF file does not exist"
>     \pdflastximagepages = DEFAULT
>     Continue
> fi
> 
> Thus \pdflastximagepages = DEFAULT means:
> "pdf file is not read" because of:
> * No \pdfximage command, program start
> * Invalid page number in previous call of \pdfximage
> * Call with valid page number, but pdf file does not exist.
> 
> The value DEFAULT can be discussed. I have not found in the
> pdf specification that pdf files with zero pages are forbidden.

Well, the catalog must have a page entry which must have kids.
But arrays can be empty, so it's possible. But I doubt that AR
will handle this. :-)

> Therefore I would prefer "-1", but the current default at
> program start is "0".

Agreed.

Overall this looks quite good. After 1.20a

Best regards
        Martin
-- 
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