Re: Probably dumb question: glyph rendering on unicode-2 branch

[Adrian Robert]

Hi,

I didn't get any response to the below, let me try asking it in a  
different way:

unicode-2 branch:
  dispextern.h:

    struct glyph {
    ...
        /* Character code for character glyphs (type ==  
CHAR_GLYPH).  */
        unsigned ch;
    ...
    }
    ...
    struct glyph_string {
    ...
    /* Characters to be drawn, and number of characters.  */
    XChar2b *char2b;
    int nchars;
    ...
    }

  {x,mac,w32}term.c:

    x_encode_char(int c, XChar2b *char2b, ...)
    {
    ...
    }

    x_draw_glyph_string(struct glyph_string *s)
    {
    ...
    }

Questions:

1) Is 'int c' passed to x_encode_char() the same as 'unsigned ch' in  
struct glpyh?

2) In either case, what are they -- UCS-2?  UTF-16?  MULE?  UCS-4?   
UTF-32?  What is the byte ordering?

I'll be happy to RTFM if this is documented anywhere..

thanks,
Adrian




On Oct 17, 2005, at 9:46 AM, Adrian Robert wrote:

> Hi,
>
> I apologize if this is a dumb question, but I've been looking  
> through the code and can't figure this one out: on the unicode-2  
> branch, if a font specifies "iso-10646-1" for XLFD registry/ 
> encoding (and then fontset.c sets 'charset' accordingly), what  
> exactly is getting passed in struct glyph_string.char2b to  
> x_draw_glyph_string()?  Not UTF-8, since it's just 2 bytes.   
> UCS-2?  UTF-16?  Don't these exclude a lot of unicode characters?   
> Is that what the "composition" machinery is for?  (But I thought  
> that had to do with the script itself involving composition, like  
> Arabic or Korean Hangul..)
>
> Does emacs provide any internal facility to get UTF-8?
>
> Also, what (encoding) is in glyph.u.ch?  Is that UCS-4?  UTF-32?
>
> thanks,
> Adrian