Subject: Re: bug#16668: 24.3; Feature Request: Face to indicate lines displayed in window that are not part of the buffer.

From: Eli Zaretskii <[email-masked]>
Date: Mon, 10 Feb 2014 19:48:38 +0200

> From: Tim Visher <[email-masked]>
> Date: Mon, 10 Feb 2014 12:07:41 -0500
> Cc: [email-masked]
> 
> >> I'd like:
> >>
> >> ```
> >> Normal Faces
> >> Normal Faces
> >> Normal Faces
> >> Normal Faces
> >> Normal Faces
> >> Face indicating not part of buffer
> >> Face indicating not part of buffer
> >> ```
> >>
> >> Or something similar.
> >
> > A great introductory exercise for anyone who would like to gain
> > experience in hacking the Emacs display engine.  Volunteers are most
> > welcome.
> 
> Sounds intriguing. Could you perhaps point me to a couple places to
> start? I wouldn't mind gaining said experience. :)

Thanks for volunteering.

The place to start learning about the display engine is the large
commentary at the beginning of xdisp.c.

The next places to look areextend_face_to_end_of_line and
display_line, both defined in xdisp.c.

After that, ask specific questions (or go ahead and write code ;-).