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General
=======
* Switch engines to be indentified by properties, instead
of hardcoded role/language. (?)
* Add a PangoLayout highlevel driver
* Add attributes data structures, feed attributed strings
into pango_itemize() (? is this necessary)
* Return error codes from all functions. Possible errors include
- Invalid string
- Font does not match
I think a good general way of doing this is to always
have an error object as a parameter to each function, but
allow that error object to be NULL, in which case a
global error object is used.
So, either
err = PANGO_ERROR_INIT;
pango_shape (..., &err);
if (PANGO_ERROR_CODE (&err) != NO_ERROR)
{
g_print ("An error %s occurred\n", PANGO_ERROR_STRING (&err));
pango_error_free (&err);
}
or:
pango_shape (..., NULL);
if (PANGO_ERROR_CODE (NULL) != NO_ERROR)
g_print ("An error %s occurred\n", PANGO_ERROR_STRING (NULL));
Also, whenever possible, the return value of each Pango function
will be a gboolean success code (and also, a pango function that
returns a pointer that cannot otherwise be NULL, will return NULL),
so we can write instead of the last one:
if (!pango_shape (..., NULL))
g_print ("An error %s occurred\n", PANGO_ERROR_STRING (NULL));
This always people who write non-threaded code to write conveniently,
while those who write threaded code can avoid pollution of return
values.
* Allow UTF8 strings with embedded NULLs.
* Write a small default shaping engine that only
draws a placeholder character ... and does that in
a way that always works.
* Convert over from utils.c to Tom Tromey's libunicode.
X fonts
=======
* Currently, for X, a language module must use a fixed priority
for the various encodings it can use; it can't distinguish:
good-unicode-subset-font
good-ksc-font
bad-unicode-full-fallback
from:
good-unicode-subset-font
bad-unicode-full-fallback
good-ksc-font
In either case if queried if a particular Unicode code-point, exists
in the font, it will return YES, and the bad-unicode-full-fallback
will be used.
void pango_x_list_subfonts (font, charsets, n_charsets, &subfonts_xlfds,
&subfont_charsets, &subfont_ids, &n_subfonts);
Note that this call adds the queried subfonts to an internal list for
the font. Subfonts once queried take up a small amount of memory
(enough for the name), subfonts, once accessed, will retain the full
amount of memory for the X font until the entire font is freed.
Then for each mask, we assemble a list of subfont-ids ordered.
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