Re: [NTG-context] Disable reuse of figures
On Sat, 19 Feb 2022, Hans Hagen via ntg-context wrote:
> On 2/19/2022 7:30 AM, Aditya Mahajan via ntg-context wrote:
> > Hi,
> >
> > This is related to a bug report for the filter module:
> > https://github.com/adityam/filter/issues/60
> >
> > Normally, when the same figure is included twice, context only includes the
> figure once and refers to the included figure the second time. The option
> `object=no` to externalfigure is supposed to prevent that, but it doesn't
> work. For example, consider the following example the bug-report uses graphviz
> as the external program, but I have changed that to context to keep things
> self contained)
> >
> > \usemodule[filter]
> >
> > \defineexternalfilter
> >[graphviz]
> >[
> > filter=context --purge,
> > output=\externalfilterbasefile.pdf,
> > readcommand=\ReadPDF,
> >]
> >
> > \def\ReadPDF#1%
> > {\externalfigure[#1][object=no]}
> >
> > \starttext
> >
> >Circle:
> >\startgraphviz
> > \startMPpage
> >draw fullcircle scaled 1cm;
> > \stopMPpage
> >\stopgraphviz
> >
> >Square:
> >\startgraphviz
> > \startMPpage
> >draw fullsquare scaled 1cm;
> > \stopMPpage
> >\stopgraphviz
> >
> > \stoptext
> >
> > Behind the scenes, the first \startgraphviz ... \stopgraphviz environment
> writes the content to an external file (\jobname-temp-graphviz.tmp), runs
> `context --purge \jobname-temp-graphviz.tmp`, which creates
> `\jobname-temp-graphviz.pdf`. The `\ReadPDF` macro then includees the file
> (with object=no).
> >
> > At the next \startgraphviz .. \stopgraphviz, the same process is repeated.
> The `\jobname-temp-graphviz.pdf` file is overwritten and the new file should
> have been included. But it is not. The output contains the first image twice.
> >
> > I thought that object=no should have prevented the reuse. In fact, if I
> compile the file with luatex, I get an error message:
> >
> > ! error: (pdf inclusion): file has changed
> '12-two-outputs-temp-graphviz.pdf'
> > mtx-context | fatal error: return code: 256
> >
> > Any idea why object=no is not working?
> the pdf file is kept open, for various reasons:
>
> - performance
> - the might be different pages to fetch
> - analysis happens when the image is placed, inclusion happens later
>
> so you try to reopen an already open file (which has not been completely
> processed)
I see. So, for the filter module this means that one always has to use
`cache=yes` (so that each PDF file has a different name). I'll add that to the
documentation.
Thanks,
Aditya
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Re: [NTG-context] Disable reuse of figures
On 2/19/2022 7:30 AM, Aditya Mahajan via ntg-context wrote:
Hi,
This is related to a bug report for the filter module:
https://github.com/adityam/filter/issues/60
Normally, when the same figure is included twice, context only includes the
figure once and refers to the included figure the second time. The option
`object=no` to externalfigure is supposed to prevent that, but it doesn't work.
For example, consider the following example the bug-report uses graphviz as the
external program, but I have changed that to context to keep things self
contained)
\usemodule[filter]
\defineexternalfilter
[graphviz]
[
filter=context --purge,
output=\externalfilterbasefile.pdf,
readcommand=\ReadPDF,
]
\def\ReadPDF#1%
{\externalfigure[#1][object=no]}
\starttext
Circle:
\startgraphviz
\startMPpage
draw fullcircle scaled 1cm;
\stopMPpage
\stopgraphviz
Square:
\startgraphviz
\startMPpage
draw fullsquare scaled 1cm;
\stopMPpage
\stopgraphviz
\stoptext
Behind the scenes, the first \startgraphviz ... \stopgraphviz environment
writes the content to an external file (\jobname-temp-graphviz.tmp), runs
`context --purge \jobname-temp-graphviz.tmp`, which creates
`\jobname-temp-graphviz.pdf`. The `\ReadPDF` macro then includees the file
(with object=no).
At the next \startgraphviz .. \stopgraphviz, the same process is repeated. The
`\jobname-temp-graphviz.pdf` file is overwritten and the new file should have
been included. But it is not. The output contains the first image twice.
I thought that object=no should have prevented the reuse. In fact, if I compile
the file with luatex, I get an error message:
! error: (pdf inclusion): file has changed '12-two-outputs-temp-graphviz.pdf'
mtx-context | fatal error: return code: 256
Any idea why object=no is not working?
the pdf file is kept open, for various reasons:
- performance
- the might be different pages to fetch
- analysis happens when the image is placed, inclusion happens later
so you try to reopen an already open file (which has not been completely
processed)
Hans
-
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
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[NTG-context] Disable reuse of figures
Hi,
This is related to a bug report for the filter module:
https://github.com/adityam/filter/issues/60
Normally, when the same figure is included twice, context only includes the
figure once and refers to the included figure the second time. The option
`object=no` to externalfigure is supposed to prevent that, but it doesn't work.
For example, consider the following example the bug-report uses graphviz as the
external program, but I have changed that to context to keep things self
contained)
\usemodule[filter]
\defineexternalfilter
[graphviz]
[
filter=context --purge,
output=\externalfilterbasefile.pdf,
readcommand=\ReadPDF,
]
\def\ReadPDF#1%
{\externalfigure[#1][object=no]}
\starttext
Circle:
\startgraphviz
\startMPpage
draw fullcircle scaled 1cm;
\stopMPpage
\stopgraphviz
Square:
\startgraphviz
\startMPpage
draw fullsquare scaled 1cm;
\stopMPpage
\stopgraphviz
\stoptext
Behind the scenes, the first \startgraphviz ... \stopgraphviz environment
writes the content to an external file (\jobname-temp-graphviz.tmp), runs
`context --purge \jobname-temp-graphviz.tmp`, which creates
`\jobname-temp-graphviz.pdf`. The `\ReadPDF` macro then includees the file
(with object=no).
At the next \startgraphviz .. \stopgraphviz, the same process is repeated. The
`\jobname-temp-graphviz.pdf` file is overwritten and the new file should have
been included. But it is not. The output contains the first image twice.
I thought that object=no should have prevented the reuse. In fact, if I compile
the file with luatex, I get an error message:
! error: (pdf inclusion): file has changed '12-two-outputs-temp-graphviz.pdf'
mtx-context | fatal error: return code: 256
Any idea why object=no is not working?
Thanks,
Aditya
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Wiki!
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archive : https://bitbucket.org/phg/context-mirror/commits/
wiki : http://contextgarden.net
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