bug#39799: 28.0.50; Most emoji sequences don’t render correctly

[Robert Pluim]

>>>>> On Fri, 28 Feb 2020 16:45:04 +0200, Eli Zaretskii <eliz@gnu.org> said:

    >> From: Robert Pluim <rpluim@gmail.com>
    >> Cc: Glenn Morris <rgm@gnu.org>,  mfabian@redhat.com,  
39799@debbugs.gnu.org
    >> Date: Fri, 28 Feb 2020 15:14:01 +0100
    >> 
    >> >> It DTRT for me under Cairo if I change my fontset settings to use
    >> >> 'Noto Color Emoji' instead of Symbola for:
    >> 
    Eli> Is that a free font (it's from Google, AFAIK, so it might not be)?  If
    Eli> it is free, we could modify fontset.el to use this font if available.
    Eli> (Or maybe there are better free Emoji fonts out there?)
    >> 
    >> Its license is Apache 2.0. It seems fairly popular. I have no opinion
    >> either way.

    Eli> What about the fact that we still support XFT?

I try to forget that :-)

    Eli> And anyway, the name "Noto Color Emoji" seems to imply it's a font
    Eli> created to display Emoji, not symbols in general, let alone non-symbol
    Eli> blocks we currently set up to use Symbola if that is available.

Right. Thereʼs a Noto Emoji font as well.

    >> As Mike clarified, you need to change the fontsets in order to get
    >> them to display in colour (uncomposed, of course).

    Eli> I don't see how that is relevant.  Fontsets are just means to cause
    Eli> Emacs use a certain font for a certain range of characters.  Fontsets
    Eli> do not affect color Emoji support.

They donʼt, no, but in this case changing the fontset was enough to
get the right glyphs to display.

Robert