# [NTG-context] Disable reuse of figures

Sat Feb 19 07:30:31 CET 2022

Hi,

This is related to a bug report for the filter module:

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,
]

{\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,