bbmath addon not working.

Tue, 01 Oct 2024 18:05:32 +0530

adminsforum@hubzilla.org

Saiwal wrote the following post Tue, 01 Oct 2024 18:06:06 +0530

bbmath addon not working.

latex and imagemagick is installed, images and tmp folder exist and have the correct permissions but i get the error

[image convert error]

The addon description says

Requires images and tmp directory in your Red root directory (e.g. /var/www/red).

I assume red refers to hubzilla? or should i create a directory named red?

show all 9 comments

Tue, 01 Oct 2024 18:37:59 +0530

Jupiter Rowland

jupiter_rowland@hub.netzgemeinde.eu

"Red" refers to the very earliest stadium of Hubzilla from 2012. It was renamed into the Red Matrix the same year and then redesigned and renamed into Hubzilla in 2015.

There's a lot of documentation for Hubzilla that has not been touched at all since Red was forked from Friendica back then.

Tue, 01 Oct 2024 20:08:21 +0530

Harald Eilertsen

harald@hub.volse.no

@Saiwal This most likely mean that the convert binary was not present, or not in it's expected location. The plugin has hardcoded an assumption that it is in /usr/bin/convert.

This also means that the rest of the conversion seems to have gone ok, so you should at the very least have a .ps file somewhere in the tmp/ dir.

This addon really could use some love! Would be a good one for someone to adopt :)

Tue, 01 Oct 2024 20:31:03 +0530

sk@hub.utsukta.org

@Harald Eilertsen yes it creates the intermediate files and cleans them up. convert is present at /usr/bin/convert on my system. I am looking at the source to understand how this works better.

Tue, 01 Oct 2024 20:41:46 +0530

Harald Eilertsen

harald@hub.volse.no

@Saiwal Could be some arguments or maybe the dependencies for convert to be able to convert from postscript to png is missing?

Tue, 01 Oct 2024 20:47:05 +0530

sk@hub.utsukta.org

@Harald Eilertsen yes. i'll look into it. it is this command that is failing:

exec($path_to_convert.' -transparent-color "#'.$back.'" -colorspace RGB -density '.$dpi.' -trim +page '.$tfn.'.ps -transparent "#'.$back.'" '.$tfn.'.'.$imgfmt);

Tue, 01 Oct 2024 20:52:18 +0530

sk@hub.utsukta.org

ok i found the issue. This happens because of Imagemagicks security policy for which in the following file /etc/ImageMagick-6/policy.xml the following two lines

<policy domain="coder" rights="none" pattern="PS" />
<policy domain="coder" rights="none" pattern="EPS" />

need to be changed to

<policy domain="coder" rights="read|write" pattern="PS" />
<policy domain="coder" rights="read|write" pattern="EPS" />

It works after this.

Tue, 01 Oct 2024 20:58:01 +0530

sk@hub.utsukta.org

Also the convert command needs a rotate argument

exec($path_to_convert.' -transparent-color "#'.$back.'" -colorspace RGB -density '.$dpi.' -trim +page -rotate -90 '.$tfn.'.ps -transparent "#'.$back.'" '.$tfn.'.'.$imgfmt);

After this it inserts latex code correctly as png

E = mc^2

Tue, 01 Oct 2024 21:18:19 +0530

Harald Eilertsen

harald@hub.volse.no

@Saiwal Cool! Do you want to submit the patch yourself, or do you need any help?

Tue, 01 Oct 2024 21:55:16 +0530

sk@hub.utsukta.org

@Harald Eilertsen I think this addon requires a lot more work. a lot of mathematical expressions like fractions are broken and multiline code is also not rendered cleanly. I'll spend some time on this and get back to you.