[dvipdfmx] \special{pdf:pageresources and named objects

[Shunsaku Hirata]

Hi Ulrike,

To address this issue, I tried several workaround which does not
require extending existing specials or introducing new one, however,
I found no satisfactory solution.

So, I may need to consider extending pdf:pageresource.
For example,

  \special{pdf:pageresource /ExtGState @testextgs}

With the above syntax, the content of @testextgs, which is reference
to a dictionary object, is to be merged to page's ExtGState resource
dictionary. (processed at the end of page)

Any suggestions on this?

> xdvipdfmx:fatal: typecheck: Invalid object type: 9 6 (line 1595)

I will fix it later.


Thanks,
Shunsaku Hirata


2019年8月7日(水) 20:39 Ulrike Fischer <news3 at nililand.de>:
>
> Hello Shunsaku,
>
> > However, if, like your examples, resource dictionary is provided as
> > an indirect reference (@testextgs is replaced by an indirect reference
> > when it is parsed), dvipdfmx can't handle it nicely.
> > Dvipdfmx need to protect page resources from being overwritten.
>
> Yes, I understand the problem.
>
> But while not using an named object but a direct value does work on
> its own, it doesn't work if the document also use
> \special{pdf:put @resources ..} with a named object:
>
>
> \documentclass{article}
>
> \usepackage{l3pdf}
> \ExplSyntaxOn
> \pdf_uncompress:
> \ExplSyntaxOff
>
> \begin{document}
> \special{pdf:obj @testextgs <<>>}
> \special{pdf:pageresources   << /ExtGState << /bearopacity <</ca 1/CA 1>>>> >>}
> \special{pdf:put @resources  << /ExtGState @testextgs >>} %as with tikz ...
> %\special{pdf:put @resources << /ExtGState << /duckopacity <</ca 0.7/CA 0.7>>>> >>}
> bbcc
> \end{document}
>
> gives
>
> xdvipdfmx:fatal: typecheck: Invalid object type: 9 6 (line 1595)
>
> (You get a similar error if you mix the syntax of two pdf:put
> @resources)
>
>
> As pgf/tikz uses
>  \special{pdf:put @resources <</ExtGState @pgfextgs >>}
> this means that \special{pdf:pageresources ..} is not really
> usable currently in a real latex document.
>
>
> --
> Mit freundlichen Grüßen
> Ulrike Fischer
>
>
>
>
>
>
>
> am Mittwoch, 7. August 2019 um 00:21 schrieben Sie:
>
> > Hi Ulrike,
>
> > For pdf:pageresources, dvipdfmx tries to merge provided resource
> > dicrionary to an existing one instead of replacing it, since dvipdfmx
> > may use its own definitions of resources internally maintained and
> > wants to preserve it (otherwise output is corrupted).
>
> > However, if, like your examples, resource dictionary is provided as
> > an indirect reference (@testextgs is replaced by an indirect reference
> > when it is parsed), dvipdfmx can't handle it nicely.
> > Dvipdfmx need to protect page resources from being overwritten.
>
> > I need to consider how to lift this restriction but I guess there must
> > be some other specials than pdf:pageresources.
>
> > Thanks,
> > Shunsaku Hirata
>
>
>
> > 2019年8月6日(火) 22:39 Ulrike Fischer <news3 at nililand.de>:
> >>
> >> Hello,
> >>
> >> with \special{pdf:put @resources ...}
> >> I can without problems use a named object:
> >>
> >> \documentclass{article}
> >>
> >> \usepackage{l3pdf}
> >> \ExplSyntaxOn
> >> \pdf_uncompress:
> >>
> >> \ExplSyntaxOff
> >>
> >> \begin{document}
> >> \special{pdf:obj @testextgs <<>>}
> >> \special{pdf:put @resources << /ExtGState @testextgs >>}
> >> \special{pdf:put @testextgs << /bearopacity <</ca 1/CA 1>>>>}
> >> \special{pdf:put @testextgs << /duckopacity <</ca 0.7/CA 0.7>>>>}
> >> abc
> >> \end{document}
> >>
> >> The resource is filled and added to the page resource:
> >>
> >> 8 0 obj
> >> <</ExtGState 4 0 R/Font<</F1 6 0 R>>/ProcSet[/PDF/Text/ImageC/ImageB/ImageI]>>
> >> endobj
> >>
> >> But when I try the same with the new pdf:pageresources
> >> the /ExtGState entrie is missing in the resource dictionary:
> >>
> >> \documentclass{article}
> >>
> >> \usepackage{l3pdf}
> >> \ExplSyntaxOn
> >> \pdf_uncompress:
> >> \ExplSyntaxOff
> >>
> >> \begin{document}
> >> \special{pdf:obj @testextgs <<>>}
> >> \special{pdf:pageresources <</ExtGState @testextgs>>}
> >> \special{pdf:put @testextgs << /bearopacity <</ca 1/CA 1>>>>}
> >> \special{pdf:put @testextgs << /duckopacity <</ca 0.7/CA 0.7>>>>}
> >> abc
> >> \end{document}
> >>
> >> 8 0 obj
> >> <</Font<</F1 6 0 R>>/ProcSet[/PDF/Text/ImageC/ImageB/ImageI]>>
> >> endobj
> >>
> >>
> >> Is this a bug or do I'm using it wrong?
> >>
> >> --
> >> Mit freundlichen Grüßen
> >> Ulrike Fischer
> >> mailto:news3 at nililand.de
> >>
> >>
>
>
>