Re: [tlug] Urxvt, Source Code Pro Font and Braille Patterns

[Curt Sampson <cjs@example.com>]

On 2018-01-10 10:11 +0100 (Wed), Jens John wrote:

> and I like to zoom in/zoom out with Ctrl+Up/Down on the fly
> 
>   URxvt.perl-ext-common:              default,matcher,font-size

That alone is worth the price of admission! I've been wanting that
for ages.

It's also nice to know that this can be done with terminal codes, in
case I ever want to script any of this stuff.

> I recommend fontmatrix.

The package was removed from Debian a couple of years ago, and it took
a bit of work to get it to compile, but I did manage to get it working
well enough to confirm that Source Code Pro does not have the Braille 
glyphs and Deja Vu Serif does. So that's helpful.

I downloaded Fantastique and I might try it out for a bit, though
because it's also not got the Braille glyphs it's orthogonal to my
issues here.

But now that I've gotten that far, I can see that the issue here seems
to be that the fallback isn't working correctly. Using `xft:DejaVu Serif`
alone, I get the Braille characters just fine. However, if I try either of:

    xft:Fantasque Sans Mono:style=Regular:size=10,xft:DejaVu Serif
    xft:Source Code Pro:size=10,xft:DejaVu Serif

it fails to print the Braille glyphs, and gives messages like the following:

    urxvt: unable to calculate font width for 'DejaVu Sans Mono:slant=0:weight=100:pixelsize=18:antialias=False:autohint=True:minspace=True', ignoring.
    urxvt: unable to calculate font width for 'Courier New:slant=0:weight=100:pixelsize=18:antialias=False:autohint=True:minspace=True', ignoring.
    urxvt: unable to calculate font width for 'Andale Mono:slant=0:weight=100:pixelsize=18:antialias=False:autohint=False:minspace=True', ignoring.
    urxvt: unable to calculate font width for 'FreeMono:slant=0:weight=100:pixelsize=18:autohint=True:minspace=True', ignoring.

A web search finally brought me to an upopular (I gave it its first upvote)
StackOverflow answer: https://unix.stackexchange.com/a/397211/10489

It seems that the problem above is produced by my `Rxvt.letterSpace:
-1.5` setting, making the Braille characters too wide to be printed.
Using `urxvt -letsp -0.5` fixed the problem for Fantastique:size=9 but
not for Source Code Pro:size=9, which needed 1.5. But noticing that
Source Code Pro:size=10 needed only 1.0 I realized that there's an
interaction between the sizes here and this is the trick:

    xft:Source Code Pro:size=10,xft:DejaVu Serif:size=9

So you got me on track to solving the problem! Thanks!

On 2018-01-10 19:40 +0900 (Wed), Stephen J. Turnbull wrote:

> Have you tried switching that last two?

Yeah, no love there. And yes, urxvt uses xft/fontconfig/etc.; I'll sit
down at some point soon, (re-) learn fontconfig, and make some notes
on it this time.

> There's a tool called gnome-font-viewer in MacPorts which is pretty
> crappy.

This, at least, does have a package, but yeah, it certainly is pretty
crappy.

cjs
-- 
Curt J. Sampson      <cjs@example.com>      +81 90 7737 2974

To iterate is human, to recurse divine.
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