Re: C equivalent for: (face-attribute 'region :background (selected-frame) 'default)

[Keith David Bershatsky]

Thank you, Eli, for looking at this particular thread.  The first draft of 
crosshairs is taking me longer than I had initially anticipated, and I still 
have not played with implementing that functionality for Emacs flavors W32 or 
X11.  So, it may be awhile before I have a draft ready.  In the meantime, I 
ported from Lisp to C the functions `face-attribute` (except the 
condition-case) and `face-attribute-merged-with':

https://lists.gnu.org/archive/html/emacs-devel/2017-09/msg00917.html

My preference is that multiple fake cursors and crosshairs be implemented 
entirely in C, with just a little bit of Lisp to access those tools.  I also 
felt that relying on Lisp might somehow slow things down a bit, and speed is 
really important.

If you or anyone is interested in adding `face-attribute` and 
`face-attribute-merged-with' to xfaces.c, the link above has my suggested 
implementation.

Keith

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DATE:  [09-29-2017 06:25:38] <29 Sep 2017 16:25:38 +0300>
FROM:  Eli Zaretskii <address@hidden>
> 
>  * * *
> 
> > Date: Tue, 26 Sep 2017 11:38:03 -0700
> > From: Keith David Bershatsky <address@hidden>
> > 
> > I have begun porting the two relevant Lisp functions to C and will submit 
> > them (when finished) in conjunction with the next draft of implementing my 
> > feature requests for crosshairs (#17684) and multiple fake cursors 
> > (#22873).  . . .
> 
> Thanks, but why would we want to port them to C?  is something wrong
> with their current Lisp implementations?