diff options
| author | W. Trevor King <wking@tremily.us> | 2013-09-21 17:06:50 -0700 |
|---|---|---|
| committer | Akira TAGOH <akira@tagoh.org> | 2013-09-24 11:19:28 +0900 |
| commit | 2b0fca14ad202d4dbd32478dc367e648833866c0 (patch) | |
| tree | e78fc39f573ec255a5e8f2d4d337249bfe654e57 /doc | |
| parent | 8a174b6c51581df6ffd6a5da056949c6c79337cf (diff) | |
doc/fccharset.fncs: Describe the map format in more detail
The previous documentation for FcCharSetFirstPage and
FcCharSetNextPage was technically accurate, but a bit terse. I've
added an example using the returned page (root code point) and map to
give folks something concrete to work with. I've also documented
FC_CHARSET_DONE, which wasn't mentioned at all before.
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/fccharset.fncs | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/doc/fccharset.fncs b/doc/fccharset.fncs index 036870d3..efcd0ccf 100644 --- a/doc/fccharset.fncs +++ b/doc/fccharset.fncs @@ -175,9 +175,27 @@ Returns whether <parameter>a</parameter> is a subset of <parameter>b</parameter> @TYPE3@ FcChar32 * @ARG3@ next @PURPOSE@ Start enumerating charset contents @DESC@ -Builds an array of bits marking the first page of Unicode coverage of -<parameter>a</parameter>. Returns the base of the array. <parameter>next</parameter> contains the next page in the -font. +Builds an array of bits in <parameter>map</parameter> marking the +first page of Unicode coverage of <parameter>a</parameter>. +<parameter>*next</parameter> is set to contains the base code point +for the next page in <parameter>a</parameter>. Returns the base code +point for the page, or <constant>FC_CHARSET_DONE</constant> if +<parameter>a</parameter> contains no pages. As an example, if +<function>FcCharSetFirstPage</function> returns +<literal>0x300</literal> and fills <parameter>map</parameter> with +<literallayout class="monospaced"> +0xffffffff 0xffffffff 0x01000008 0x44300002 0xffffd7f0 0xfffffffb 0xffff7fff 0xffff0003 +</literallayout> +Then the page contains code points <literal>0x300</literal> through +<literal>0x33f</literal> (the first 64 code points on the page) +because <parameter>map[0]</parameter> and +<parameter>map[1]</parameter> both have all their bits set. It also +contains code points <literal>0x343</literal> (<parameter>0x300 + 32*2 ++ (4-1)</parameter>) and <literal>0x35e</literal> (<parameter>0x300 + +32*2 + (31-1)</parameter>) because <parameter>map[2]</parameter> has +the 4th and 31st bits set. The code points represented by +<literal>map[3]</literal> and later are left as an excercise for the +reader ;). @@ @RET@ FcChar32 @@ -187,9 +205,15 @@ font. @TYPE3@ FcChar32 * @ARG3@ next @PURPOSE@ Continue enumerating charset contents @DESC@ -Builds an array of bits marking the Unicode coverage of <parameter>a</parameter> for page -<parameter>*next</parameter>. Returns the base of the array. <parameter>next</parameter> contains the next page in -the font. +Builds an array of bits in <parameter>map</parameter> marking the +Unicode coverage of <parameter>a</parameter> for page containing +<parameter>*next</parameter> (see the +<function>FcCharSetFirstPage</function> description for details). +<parameter>*next</parameter> is set to contains the base code point +for the next page in <parameter>a</parameter>. Returns the base of +code point for the page, or <constant>FC_CHARSET_DONE</constant> if +<parameter>a</parameter> does not contain +<parameter>*next</parameter>. @@ @RET@ FcChar32 |