Bug#1003255: (no subject)

[Peter Mueller]

Package: texlive-pstricks

Version: 2021.20211217-1

Let's construct mwe.tex containing

\documentclass{article}
\usepackage{pstricks}
\begin{document}
test
\end{document}

and run

latex mwe && dvipdf mwe

or

latex mwe && dvips mwe && ps2pdf mwe.ps

This prints

%%%% WARNING: Transparency operations ignored - need to use -dALLOWPSTRANSPARENCY

on a tty. Of course, one can do as the message says and add the corresponding command-line option. Still, I feel that the transparency stuff shouldn't even be in the Postscript file unless it is really used. So could pstricks be a bit more economical and not issue the transparency-related commands by default (or, equivalently, issue them only if opacity and the like is really used in the user's LaTeX input)? Alternatively or in addition, could ghostscript be a little less fussy about transparency and make ALLOWPSTRANSPARENCY default?

Bug report: https://tex.stackexchange.com/questions/629314 . The PStricks maintainers have been informed, too, just in case they don't have an update for this issue yet.




Thank you in advance,

Peter

[Hilmar Preuße]

Control: severity -1 minor

Am 07.01.2022 um 02:40 teilte Peter Mueller mit:

HI Peter,

> Package: texlive-pstricks
> Version: 2021.20211217-1

> Bug report: https://tex.stackexchange.com/questions/629314
> https://tex.stackexchange.com/questions/629314. The PStricks

> maintainers have been informed, too, just in case they don't have an
> update for this issue yet.
>

If you forwarded the issue to pstricks, could you leave a link here?

Hilnar
--
sigfault

[Peter Mueller]

Thanks, Hilmar!

I sent the report by e-mail to PSTricks maintainers and already got an answer from them. It seems to me they see it as a warning rather than a bug. Hoewever, in my view, compiling a LaTeX document without transparency and getting a warning about transparency down the toolchain with default settings is strange. You could have been (perhaps, legitimately) warned if there is real transparency in your LaTeX document, but if you don't have transparency or don't know whether you have transparency (e.g., because your document is huge or written by someone else), an excessful warning is, well, more bothering than helpful. I'd prefer that the transparency code doesn't even get into the Postscript file if transparency isn't used in the source LaTeX document.

Cheers,

Peter

07.01.2022, 12:13, Hilmar Preuße <hil...@web.de>

[Hilmar Preusse]

Control: retitle -1 PSTricks requests to use -dALLOWPSTRANSPARENCY even if not needed.

On 07.01.22 Peter Mueller (peterm...@ro.ru) wrote:

Hi,

giving that bug a sane title.

Hilmar

[Hilmar Preuße]

Control: tags -1 + wontfix

Am 07.01.2022 um 13:50 teilte Peter Mueller mit:

Hi,

> but if you don't have transparency or don't know whether you have
> transparency (e.g., because your document is huge or written by
> someone else), an excessful warning is, well, more bothering than
> helpful. I'd prefer that the transparency code doesn't even get into
> the Postscript file if transparency isn't used in the source LaTeX
> document.

>As explained by upstream:

That behaviour will not be changed! PSTricks has no internal check if
someone uses the opacity or strokeopacity options. You can use instead
lualatex then you do not need the ghostscript run.

Other methods to avoid the warning were suggested on
https://tex.stackexchange.com/q/629314/50836

So I tag wontfix.

H.
--
sigfault

[Peter Müller]

tags 1003255 - wontfix
severity 1003255 normal
thanks


It's not the presence or absence of any such check that makes it into a
bug. It's the resulting behavior that has a bug.

E.g., you could implement this by checking at the beginning of the
document whether the information in the aux file says the opacity code
should be emitted. If so, emit the code and set a Boolean macro, say,
“\transparencyCodeWritten” to “true”, otherwise to “false”. Then,
whenever a transparency/opacity-related operation is encountered, test
whether “\transparencyCodeWritten” is still “false” and if so, emit the
transparency/opacity-related code to the output if possible immediately
(I don't now Postscript enough to say this) and set
“\transparencyCodeWritten” to “true”. If not possible immediately,
write a flag info the aux file to be read at the next LaTeX run.

There might be other ways to repair this.

If a user such as you or me or (or even user187802, even if they are the
current maintainer) refuses to implement this, it's his or her right
(since it's all done in free, unpaid time, and only very few people
worldwide have it), but this doesn't make the current behavior less
erroneous. Maintainers and users come and go, and PStricks stays.

P.