[racket] text/font not rendering symbol fonts on WinXP

Robby's answer is in principle right: `racket/draw' really wants to
work with Unicode characters, and the right way to access dingbat-like
glyphs is to use the corresponding Unicode code point. The
`racket/draw' library mostly inherits this policy from Pango.

Under Windows, Pango ignores "Wingdings" because it's a non-Unicode
symbol font. The same thing happens with "EZ Special-I" from
"ByzMusicFonts". We may want to change Pango's behavior in the copy
that is distributed with Racket; more on that below.

On a normal Ubuntu installation, I believe the "Dingbats" font is set
up for Unicode-style use, and that's why "012abc" renders as "012abc".
The glyphs probably are not taken from the "Dingbats" font but found
through fallbacks in another font. If you want a snowflake, use
"\u2744", and that should work everywhere. Of course, you don't
actually want a snowflake, so that's not the end of the story.


When I install "EZ Special-I" in Ubuntu, then... well, Racket crashes
due to problems with missing glyphs. But with the repair that I just
pushed to the Racket source repo, the text renders in the way you
expect. The Pango behavior on Ubuntu seems to be to allow the font use,
even though the font claims to be a symbol font --- perhaps on the
assumption that fonts will be well behaved from the Unicode perspective
(in contrast to Windows, where non-well-behaved fonts are available by
default).


I think we should probably patch Racket's version of Pango for Windows
to allow the use of symbol fonts. A danger of this hack is that a
symbol font might be used as a fallback for a normal glyph when the
glyph isn't found in some other font. I think that danger is low,
though, and the consequences of failure seem relatively minor (i.e.,
just pick a different main font). Furthermore, my Win7 installation
seems to have fonts that act like symbol fonts but apparently don't
claim to be, which defeats Pango's existing check.

Unfortunately, patching Pango means compiling it myself for Windows,
which is a tedious task that I had so far avoided. Maybe it's
unavoidable, though.


At Fri, 23 Nov 2012 15:55:43 -0500, Clement Erik Ferguson wrote:
> I'm sorry, I don't think I've explained the problem I'm having clearly.
> 
> I have fonts that I'm using that map latin characters to neumes for
> byzantine chant music. So pressing "1" gives me a particular musical
> symbol, and "a" gives me another symbol. I am trying to use text/font to
> render those symbols, so I call it with a "1" but I'm getting a "1" instead
> of the musical symbol on certain platforms. This method works fine on
> Ubuntu 12.04 32bit and a Debian system that another user tested it on (I'm
> not sure of the version info), but it isn't working on Windows XP and on
> Ubuntu 12.10 64bit.
> 
> If you go to https://github.com/muraiki/byzscribe and scroll down to the
> picture, you can see what the output should look like. On platforms where
> it doesn't work, instead of getting the musical symbols I simply get the
> textual string that should map to those symbols, such as 01a.
> 
> You can download the font package, which includes a PDF with a character
> table, from here:
> http://www.stanthonysmonastery.org/music/ByzMusicFonts.zipThe
> character table is EZ-CharacterTables.pdf
> 
> The other symbol fonts that I've tried work in the same way, although
> instead of musical symbols they have other things like snowflakes and
> shapes. Those aren't the fonts that I need to use, but I wanted to make
> sure that the problem didn't lie in the byzantine chant fonts. On platforms
> where the byzantine chant fonts don't work as expected, no other symbol
> fonts work, either.
> 
> I'm sorry if this is a bit confusing. Thank you for your help!
> 
> 
> On Fri, Nov 23, 2012 at 3:38 PM, Robby Findler
> <robby at eecs.northwestern.edu>wrote:
> 
> > If you want to use, say, α, then you need an actual α in the string, not
> > an "a".
> >
> > I don't know how the dingbats work, but certainly that's how it works
> > for characters that are in the unicode character set.
> >
> > (You can type those characters by using their LaTeX equivalents and
> > then hitting control-\ or alt-\ (depending on the platform).)
> >
> > Robby
> >
> > On Fri, Nov 23, 2012 at 2:02 PM, Clement Erik Ferguson
> > <clementraphael at gmail.com> wrote:
> > > Now I'm experiencing the same problem in Ubuntu 12.10. No symbol fonts
> > > render when using text/font; I only get the latin text equivalent. I
> > tried
> > > this using the Dingbats font built into Ubuntu along with custom symbol
> > > fonts I had downloaded. Both Dingbats and the other symbol fonts I
> > > downloaded work fine in other programs.
> > >
> > > The system where this did work correctly was an Ubuntu 12.04 machine
> > > (running under a VM). The Ubuntu 12.10 machine I'm using now is a fresh
> > OS
> > > installation using the 64-bit binary downloaded from the Racket site.
> > >
> > > Is anyone else using Ubuntu 12.10? Can you try running the following
> > code?
> > >
> > > (require 2htdp/image)
> > > (text/font "test" FONT-SIZE "black" "Dingbats" 'symbol 'normal 'normal
> > #f)
> > >
> > > This should render some triangles and a snowflake, not "test".
> > >
> > > Thanks!
> > >
> > >
> > > On Wed, Nov 21, 2012 at 1:54 PM, Robby Findler <
> > robby at eecs.northwestern.edu>
> > > wrote:
> > >>
> > >> The text/font function ultimately just calls find-or-create-font with
> > >> the font details and then draw-string on the dc<%> with the string, so
> > >> I guess that this is either a problem at that level of the Racket GUI
> > >> system, or something that is just different about how Windows works
> > >> from other platforms. (Sorry I don't know the right answer here.)
> > >>
> > >> Robby
> > >>
> > >> On Wed, Nov 21, 2012 at 12:29 PM, Clement Erik Ferguson
> > >> <clementraphael at gmail.com> wrote:
> > >> > Hi all,
> > >> >
> > >> > I'm a newcomer to Racket and I ran into a problem with the text/font
> > >> > function in 2htdp/image. stamourv on #racket helped me diagnose this,
> > >> > and it
> > >> > seems to be a problem confined to Windows XP. When using text/font
> > with
> > >> > a
> > >> > symbol font like Wingdings or Symbol (standard symbol fonts included
> > >> > with
> > >> > Windows) the character is not rendered. Instead, I get whatever the
> > >> > equivalent Roman character would be.
> > >> >
> > >> > For instance:
> > >> >
> > >> > (define testingfont
> > >> >   (text/font "012abc" 36 "black"
> > >> >              "Wingdings" 'default 'normal 'normal #f))
> > >> >
> > >> > If I then type testingfont into the interactions window, instead of
> > >> > rendering a series of symbols I get the input string 012abc instead. I
> > >> > also
> > >> > tried using 'symbol instead of 'default. We tried the same code on
> > >> > Debian
> > >> > (stamourv) and Ubuntu (me) and it worked fine on those platforms.
> > >> >
> > >> > I'm running Windows XP 32-bit, and I am using Racket 5.3.1.
> > >> >
> > >> > Thanks!
> > >> >
> > >> > ____________________
> > >> >   Racket Users list:
> > >> >   http://lists.racket-lang.org/users
> > >> >
> > >
> > >
> >
> ____________________
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