docs/html/integration-icu.html

   1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
   2 <html>
   3 <head>
   4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
   5 <title>ICU integration: HarfBuzz Manual</title>
   6 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
   7 <link rel="home" href="index.html" title="HarfBuzz Manual">
   8 <link rel="up" href="integration.html" title="Platform Integration Guide">
   9 <link rel="prev" href="integration-coretext.html" title="Core Text integration">
  10 <link rel="next" href="integration-python.html" title="Python bindings">
  11 <meta name="generator" content="GTK-Doc V1.32.1 (XML mode)">
  12 <link rel="stylesheet" href="style.css" type="text/css">
  13 </head>
  14 <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
  15 <table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle">
  16 <td width="100%" align="left" class="shortcuts"></td>
  17 <td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td>
  18 <td><a accesskey="u" href="integration.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td>
  19 <td><a accesskey="p" href="integration-coretext.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
  20 <td><a accesskey="n" href="integration-python.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
  21 </tr></table>
  22 <div class="section">
  23 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
  24 <a name="integration-icu"></a>ICU integration</h2></div></div></div>
  25 <p>
  26       Although HarfBuzz includes its own Unicode-data functions, it
  27       also provides integration APIs for using the International
  28       Components for Unicode (ICU) library as a source of Unicode data
  29       on any supported platform.
  30     </p>
  31 <p>
  32       The principal integration point with ICU is the
  33       <span class="type">hb_unicode_funcs_t</span> Unicode-functions structure
  34       attached to a buffer. This structure holds the virtual methods
  35       used for retrieving Unicode character properties, such as
  36       General Category, Script, Combining Class, decomposition
  37       mappings, and mirroring information.
  38     </p>
  39 <p>
  40       To use ICU in your client program, you need to call
  41       <code class="function">hb_icu_get_unicode_funcs()</code>, which creates a
  42       Unicode-functions structure populated with the ICU function for
  43       each included method. Subsequently, you can attach the
  44       Unicode-functions structure to your buffer:
  45     </p>
  46 <pre class="programlisting">
  47       hb_unicode_funcs_t *icufunctions;
  48       icufunctions = hb_icu_get_unicode_funcs();
  49       hb_buffer_set_unicode_funcs(buf, icufunctions);
  50     </pre>
  51 <p>
  52       and ICU will be used for Unicode-data access.
  53     </p>
  54 <p>
  55       HarfBuzz also supplies a pair of functions
  56       (<code class="function">hb_icu_script_from_script()</code> and
  57       <code class="function">hb_icu_script_to_script()</code>) for converting
  58       between ICU's and HarfBuzz's internal enumerations of Unicode
  59       scripts. The <code class="function">hb_icu_script_from_script()</code>
  60       function converts from a HarfBuzz <span class="type">hb_script_t</span> to an
  61       ICU <span class="type">UScriptCode</span>. The
  62       <code class="function">hb_icu_script_to_script()</code> function does the
  63       reverse: converting from a <span class="type">UScriptCode</span> identifier
  64       to a <span class="type">hb_script_t</span>.
  65     </p>
  66 <p>
  67       By default, HarfBuzz's ICU support is built as a separate shared
  68       library (<code class="filename">libharfbuzz-icu.so</code>)
  69       when compiling HarfBuzz from source. This allows client programs
  70       that do not need ICU to link against HarfBuzz without unnecessarily
  71       adding ICU as a dependency. You can also build HarfBuzz with ICU
  72       support built directly into the main HarfBuzz shared library
  73       (<code class="filename">libharfbuzz.so</code>),
  74       by specifying the <code class="literal">--with-icu=builtin</code>
  75       compile-time option.
  76     </p>
  77 </div>
  78 <div class="footer">
  79 <hr>Generated by GTK-Doc V1.32.1</div>
  80 </body>
  81 </html>