POV-Ray : Newsgroups : povray.windows : Double-byte font trouble : Re: Double-byte font trouble Server Time
28 Jul 2024 18:22:20 EDT (-0400)
  Re: Double-byte font trouble  
From: Ron Parker
Date: 25 Jan 1999 10:13:26
Message: <36ac8a16.0@news.povray.org>
On Sat, 23 Jan 1999 01:15:08 -0800, Jon A. Cruz <jon### [at] geocitiescom> wrote:
>"Ronald L. Parker" wrote:
>My suggestion is to go ahead and drop MBCS and switch to UTF-8 for Unicode.
>That allows specifying Unicode chars, but ASCII chars 0-0x7f stay the same.
>
>That way any standard POV files will work untouched, and only files edited
>for a MBCS patched version would need converting. That can also eleminate a
>need for a flag to signal Unicode mode.

For the record, I really like this idea and will probably switch to 
UTF-8 in the next Superpatch (whenever THAT is...)  I might also add 
a switch to allow you to use plain ol' UCS-2, just to make it easier 
to do a character or two from a Unicode font using the NT Character 
Map application or the charts at unicode.org.  

There'll be a problem for those of you who regularly use the 8-bit 
characters in ISO Latin-1, though.  If anyone who regularly uses 
8-bit characters has an idea how this can be implemented such that 
it's backward-compatible with the official version of POV, please 
speak up.  I think I can detect that a given string of characters 
is not valid UTF-8 and fall back to the 8-bit CMAP table, but 
this doesn't work in 100% of cases.  Some perfectly valid but 
unlikely strings of 8-bit characters could map to weird glyphs.

You would need three high-bit characters in a row, the first one 
has to be one of the sixteen characters that has a high nybble of 

high nybble of $8 through $B. (mostly symbols of one form or 
another, unlikely to be inside or at the end of a word, particularly
in combination, though there are conceivable exceptions.)  Some of 
the combinations thus formed might even be valid in the font you're 
using (particularly if you're using a Unicode font on NT, most of 
which include Arabic and Hebrew script.)


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.