Add support for :stipple face attribute

[jasonmj]

In order to use the indent-bars package, support for the :stipple face attribute is required:
https://github.com/jdtsmith/indent-bars#compatibility

Could hombrew-emacs-plus support this feature?

[d12frosted]

hey @jasonmj

That sounds interesting. Ideally I try to keep Emacs+ as close to GNU Emacs as possible with a few notable exceptions. The question is where to draw the line. XWidgets is a kind of an experiment that I am not sure I would love to add today. But there are safe and quite simple extras that I see no harm in adding.

In general, I see value in adding :stripple support. The only issue - I am not familiar with Emacs sources, so I don't really know what needs to be done. After a quick googling, I found a commit in emacs-mac that added :strippe support. I haven't tried it yet, but maybe we can use it as a patch for GNU Emacs as well. Will play around with this idea later¹.

Ideally, this support should come in GNU Emacs. I couldn't find relevant feature request for macOS specifically in the mailing list (although my search skills are not that good), so maybe you can start a new request.

Hope this makes sense 😅

Footnotes

1. Holy moly, I've promised to check so many things related to Emacs+ and I just can't find enough time to do everything, so don't trust me when I say 'I will'. ↩

[jasonmj]

Thanks for the response! I wish I had more experience working with MacOS, but I come from NixOS primarily. My usage of MacOS is just for work.

From what I can tell, the big difference between emacs-plus and emacs-mac is that emacs-plus doesn't include modifications to the underlying c code that Emacs depends on. Instead, it's more of a build configuration automation tool, but maybe using a modified version of the patch from emacs-mac could work?

The official support in GNU Emacs is configured to use X11 compatible bitmaps:
https://github.com/emacs-mirror/emacs/blob/master/src/bitmaps/stipple.xbm

Looks like there was some relevant discussion on adding support for the stipple face attribute on PGTK in this thread:
https://lists.gnu.org/archive/html/bug-gnu-emacs/2023-08/msg00010.html

I'll chime in here if I can find anything else that seems helpful.