Re: [Pre-PATCH] Overhaul of the LaTeX preview system

[Visuwesh]

[திங்கள் ஆகஸ்ட் 21, 2023] Karthik Chikmagalur wrote:

>> It worked well all around except for three things:
>>
>>     1. I had to set org-latex-preview-precompile to nil to produce the
>>        preview for ~2000 snippets.  I got errors in process filters such
>>        as arg-out-of-range, and Emacs completely blocked itself.  I can
>>        confirm that mylatexformat is installed
>
> 1. Are you using xelatex/lualatex?  

I have lualatex installed as part of another texlive package but I am
not sure if org uses it however.

> 2. If yes, precompilation should have turned itself off with a warning.
> 3. If no, do you mind sharing this file (or a stripped down version
> you're okay sharing that still has these issues) along with the LaTeX
> preamble?  That would be `org-latex-preview-preamble' and
> `org-latex-packages-alist'.  I would like to reproduce this bug.
>
> Previewing 2000 snippets is exactly where the new async/speedy system is
> expected to shine compared to the old one.
>
>>     2. Apparently, org-latex-default-packages-alist no longer contain
>>        asmsymb and asmmath?  This change pulled the rug under me since
>>        it took me quite a while to figure out why some of my formulas
>>        were coloured red...
>
> `org-latex-default-packages-alist' was modified to omit amsmath and
> amssymb (among others) in preparation for a conditional export system
> where required packages will be determined automatically from the buffer
> text -- i.e. to avoid exactly the kind of headache you encountered.
> Unfortunately this export system is not part of the patch set yet.

Ah, OK.  I will add them in my config and call it a day.  ;-)

>>     3. The image sizes of the same latex environment (e.g., \[ \]) is
>>        different for different formulas.  I can send a screenshot of
>>        this if required.
>
> This is a recent regression.  Could you generate png previews by:
>
> 1. (setq org-latex-preview-default-process 'dvipng)
> 2. regenerating previews
>
> and checking if this still happens?  If these look fine, this is a
> dvisvgm issue and we will fix it soon.

No, AFAICT I don't see the issue with png previews.  However, all latex
previews, \( \) and \[ \], seem to be of the same size now.

>>> If you do come across any issues, please let me know either in a reply here 
>>> or
>>> the org-mode matrix room. If you could also run
>>> <https://gist.github.com/karthink/0ac48411a81459c0f3fd7557c4e817db> and 
>>> share the
>>> diagnostic info, that would be quite helpful.
>>
>> If needed, I can do this after reproducing (1).
>>
>> BTW, would it possible to arrange other latex environments (\ch{} in my
>> case) to be previewed as well?  Currently, I do \(\ch{}\) but omitting
>> \( \) would be nice.
>
> Previewing unadorned LaTeX macros is officially unsupported but
> partially supported in practice.  If you move the cursor over the \ch{}
> and call `org-latex-preview' it should be previewed.  From that point it
> should behave like a regular LaTeX fragment.  Editing it should cause
> the preview to be auto-updated (If you are using
> org-latex-preview-auto-mode).

Is there no automagic way to do this?  Like changing a regexp variable
and hoping it would work till the end of time™.  (:

> Karthik