bug#70697: 30.0.50; Frame parameter alpha-background is ignored for fringe bitmaps & internal borders

[Eli Zaretskii <eliz@gnu.org>]

Ping!  Can we make some further progress with this issue?

> From: Aleksandar Dimitrov <mail@aleks.bg>
> Date: Thu, 16 May 2024 16:26:47 +0200
> CC: eliz@gnu.org,  70697@debbugs.gnu.org
> 
> Hello Po Lu,
> 
> > This has been previously reported.  As I've stated on those occasions
> > and numerous others, the internal border is a _border_, a natural
> > component of a frame's foreground that should not be affected by its
> > background transparency properties.
> 
> Thanks for your feedback. I didn't find any previous discussions, but I
> guess I didn't look hard enough, sorry for that. Is there another way to
> create insets in Emacs that does respect transparency settings? Or is
> there a way to tweak the frame border's transparency settings that
> doesn't also affect the rendered text and other interactive elements?
> 
> What I'm looking for is to distance the text somewhat from the edge of
> the frame to create some negative space.
> 
> > As regards fringe bitmaps, they respond to alpha-background on the
> > XRender builds.  This (untested) patch might extend this to Cairo
> > builds:
> 
> Thanks for the patch. I applied it to the current Emacs (on top of
> 407b88333) and came to the following conclusion:
> 
> When compiling Emacs with --with-toolkit=lucid, the above patch
> works. Fringe bitmaps' backgrounds are now transparent.
> As before, the internal borders aren't transparent.
> 
> When compiling Emacs instead with --with-pgtk, the above patch *does not
> work*. However, the internal frame borders *are* transparent there
> now. I haven't yet investigated whether that was always the case (and I
> simply hadn't compiled Emacs correctly before) or whether that change
> came in recently.
> 
> I guess the behaviour (whatever it ends up being) should be consistent across toolkits.
> 
> Thanks,
> Aleks
>