Re: Using org-latex-preview in other major modes

[Karthik Chikmagalur <karthikchikmagalur@gmail.com>]

> Abstracting away previews is certainly welcome.
> RMS explicitly asked Org mode team to work towards this goal:
> https://list.orgmode.org/E1kIkxv-0007iy-Av@fencepost.gnu.org/

I agree with RMS about this, and this was on our minds when we wrote
org-latex-preview.  The basic previewing process is explicitly written
to be Org-agnostic, but we weren't as rigorous when adding the fancier
features (like live previews).

> Ideally, we should have Org-independent library that does the previews,
> and an Org-specific code that re-uses this library. Eventually, we can
> move the generic library to Emacs core.

Here is the plan Timothy and I have discussed:

1. Merge org-latex-preview in its current state and continue to fix
bugs/edge cases.
2. Write an external package reimplementing in a more generic way the
parts of the API that are Org-specific.  This external package will
depend (heavily) on org-latex-preview.
3. Solicit from the community integrations of this with other
major-modes using this generic API.
4. Once this API is stable, replace the corresponding parts of
org-latex-preview.
5. Propose moving everything but the Org-specific parts to a
`latex-preview.el' package included with Emacs.

From Tony's proof of concept, I think step 2 might be unnecessary and we
can incrementally modify org-latex-preview instead.

> We may go even further, and extend the previews to be not just for
> LaTeX. Might as well preview html/image links/pdf links/etc.

I agree in principle but I think this is difficult to do with
org-latex-preview because the async process chain and overlay handling are
highly tuned for low-latency LaTeX processing.[1] 

I do think Emacs could use a generic link-preview package, with an
org-link-preview adapter for Org mode.

Karthik

[1]: As low-latency as possible from Emacs without modifying
the LaTeX compiler or image renderer, as for example TeXpresso
does. https://github.com/let-def/texpresso