Re: Suggest installing more fonts?

[Gregory Heytings]

> Let's keep the discussion in context, okay?  The context was the 
> complaints that Emacs displays tofu where other applications display 
> characters from installed fonts (which aren't GNU Unifont).  It is those 
> use cases that I was talking about.  Where Emacs behaves no worse than 
> other apps is in a different category.  More about that below.

That was not the meaning of Lars' message 24 hours ago:

> I think, over the years, the most common question users have that has an 
> easy-to-fix solution is: "Why is Emacs displaying boxes for some of 
> these characters I'm seeing?"  The solution is "install some more 
> fonts", of course.
>
> But could Emacs be more helpful here?  That is, could we somehow, 
> unobtrusively, tell the users this when Emacs is trying to display a 
> character that it has no fonts for?
>
> For added helpfulness, would it be possible for Emacs to be even more 
> specific?  Like, say "sudo apt install fonts-noto-color-emoji 
> fonts-symbola", or whatever, depending on the system.

About the use cases you are talking about, I haven't seen cases where 
"Emacs displays tofu where other applications display characters from 
installed fonts".  My experience is that Emacs behaves better than many 
other applications in this respect (except for the particular case of 
Emojis).

> The Emoji problem was already analyzed and a solution is in the works 
> which will not look anywhere like the above (setting up the fontset is 
> not enough, btw).  Let's move on to problems for which we don't yet have 
> a solution, okay?

I was not aware that you were working on a solution to the Emoji problem 
before I read your last email.  My (admittedly hacky) solution works fine, 
in fact it makes Emacs behave better than any other program (browser or 
editor) on my computer, so I don't understand why you write that it's not 
enough.  I'll continue to use it, until the better solution arrives.

> > The meaning of my proposal was, in fact, the exact opposite of an 
> > admission of defeat, it was to make Emacs better in that respect than 
> > all other apps.  Displaying a tofu is an admission of defeat, and it's 
> > what all other apps do.
>
> Using Unifont is a defeat in the sense that we don't do better by 
> finding a good font.  The Unifont "solution" is already in Emacs, see 
> the setting of fontset-default.  So if you are willing to settle for 
> Unifont, we already do that.  IMO, we should try to find ways to do 
> better than that.

My proposal was for the cases where _no_ suitable font exists.  In that 
case it is by definition impossible to find a good font.  And no, the 
Unifont solution is not already _in_ Emacs, because it requires to install 
a particular additional package/font (Unifont), which is something most 
users will not do.  The meaning of my proposal was only to include it _in_ 
Emacs, in short, to use, when it exists, the Unifont glyph in 
produce_glyphless_glyph() instead of creating a tofu with a hexcode. 
(For example, C-h h should IMO not display a single tofu.)

> Do you read the Tamil script (I don't)?  If not, we should ask someone 
> who does what they think about the Unifont glyphs.  (To my un-expert 
> eyes, the right-most glyph looks completely unrecognizable with Unifont, 
> but that's me.)

I do not read the Tamil script, but when I compare this to the variety of 
fonts in the languages I read, I doubt a Tamil reader would be unable to 
understand that text because that right-most glyph is not exactly 
positioned as it should be.

> In any case, it is never a bad idea to try find better ways of handling 
> this situation than we already have.  For starters, I'm not sure I 
> understand what kinds of situation is it that the user wants to read 
> Tamil text, but the system isn't ready for that wrt installed fonts.

This does happen in practice.  For example when opening a source file with 
comments written in a foreign language.  In that case I'm not necessarily 
interested in actually reading that text, but I'd like to see at least 
what these characters are/look like.  Another case when this does happen 
in practice is (as Lars mentioned in his message) for Emojis, in which 
case I'd like to have at least an idea of what the Emoji represents.  Yet 
another case would be when visiting a website written in a foreign 
language with eww, again I'm probably not interested in reading the text 
but seeing tofus is just ugly.  And so forth.