Re: Mouse-hovering over 'mouse-face' overlays/regions on a TTY Emacs

[João Távora]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: João Távora <joaotavora@gmail.com>
>> Cc: Jared Finder <jared@finder.org>,  emacs-devel@gnu.org
>> Date: Mon, 30 Nov 2020 16:25:37 +0000
>> 
>> To recap, help-echo works fine, but mouse-face is somehow missing (on
>> TTY only).
>
> It works for me on the w32 TTY, so something else is at work here.
> More debugging is needed, I think.  Specifically, note_mouse_highlight
> is supposed to redraw some of the glyphs with the mouse-face.  If the
> function is called, please step through it and try to figure out why
> the redrawing doesn't happen -- what prevents that?

I think I figured it out.  draw_row_with_mouse_face() is eventually
called by show_mouse_face(), but it is a noop on my system.  Easy to
see:

static void
draw_row_with_mouse_face (struct window *w, int start_x, struct glyph_row *row,
                          int start_hpos, int end_hpos,
                          enum draw_glyphs_face draw)
{
#ifdef HAVE_WINDOW_SYSTEM
   ...
#endif
#if defined (HAVE_GPM) || defined (MSDOS) || defined (WINDOWSNT)
  tty_draw_row_with_mouse_face (w, row, start_hpos, end_hpos, draw);
#endif
}


I'm currently using Mac OS.  Most of the TTY things work here, and I
would expect drawing some face on a part of the screen to work too.  I
can certainly show and hide faces programatically.

I've tried uncommenting that, but it fails during linking.

João