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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>User Fonts: Cairo: A Vector Graphics Library</title>
6 <meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
7 <link rel="home" href="index.html" title="Cairo: A Vector Graphics Library">
8 <link rel="up" href="cairo-fonts.html" title="Fonts">
9 <link rel="prev" href="cairo-Quartz-(CGFont)-Fonts.html" title="Quartz (CGFont) Fonts">
10 <link rel="next" href="cairo-surfaces.html" title="Surfaces">
11 <meta name="generator" content="GTK-Doc V1.27 (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">
17 <a href="#" class="shortcut">Top</a><span id="nav_description">  <span class="dim">|</span> 
18 <a href="#cairo-User-Fonts.description" class="shortcut">Description</a></span>
19 </td>
20 <td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td>
21 <td><a accesskey="u" href="cairo-fonts.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td>
22 <td><a accesskey="p" href="cairo-Quartz-(CGFont)-Fonts.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
23 <td><a accesskey="n" href="cairo-surfaces.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
24 </tr></table>
25 <div class="refentry">
26 <a name="cairo-User-Fonts"></a><div class="titlepage"></div>
27 <div class="refnamediv"><table width="100%"><tr>
28 <td valign="top">
29 <h2><span class="refentrytitle"><a name="cairo-User-Fonts.top_of_page"></a>User Fonts</span></h2>
30 <p>User Fonts — Font support with font data provided by the user</p>
31 </td>
32 <td class="gallery_image" valign="top" align="right"></td>
33 </tr></table></div>
34 <div class="refsect1">
35 <a name="cairo-User-Fonts.functions"></a><h2>Functions</h2>
36 <div class="informaltable"><table class="informaltable" width="100%" border="0">
37 <colgroup>
38 <col width="150px" class="functions_return">
39 <col class="functions_name">
40 </colgroup>
41 <tbody>
42 <tr>
43 <td class="function_type">
44 <a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
45 </td>
46 <td class="function_name">
47 <span class="c_punctuation">(</span><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-init-func-t" title="cairo_user_scaled_font_init_func_t ()">*cairo_user_scaled_font_init_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
48 </td>
49 </tr>
50 <tr>
51 <td class="function_type">
52 <a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
53 </td>
54 <td class="function_name">
55 <span class="c_punctuation">(</span><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-render-glyph-func-t" title="cairo_user_scaled_font_render_glyph_func_t ()">*cairo_user_scaled_font_render_glyph_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
56 </td>
57 </tr>
58 <tr>
59 <td class="function_type">
60 <a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
61 </td>
62 <td class="function_name">
63 <span class="c_punctuation">(</span><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()">*cairo_user_scaled_font_text_to_glyphs_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
64 </td>
65 </tr>
66 <tr>
67 <td class="function_type">
68 <a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
69 </td>
70 <td class="function_name">
71 <span class="c_punctuation">(</span><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()">*cairo_user_scaled_font_unicode_to_glyph_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
72 </td>
73 </tr>
74 <tr>
75 <td class="function_type">
76 <a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="returnvalue">cairo_font_face_t</span></a> *
77 </td>
78 <td class="function_name">
79 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-create" title="cairo_user_font_face_create ()">cairo_user_font_face_create</a> <span class="c_punctuation">()</span>
80 </td>
81 </tr>
82 <tr>
83 <td class="function_type">
84 <span class="returnvalue">void</span>
85 </td>
86 <td class="function_name">
87 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-set-init-func" title="cairo_user_font_face_set_init_func ()">cairo_user_font_face_set_init_func</a> <span class="c_punctuation">()</span>
88 </td>
89 </tr>
90 <tr>
91 <td class="function_type">
92 <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-init-func-t" title="cairo_user_scaled_font_init_func_t ()"><span class="returnvalue">cairo_user_scaled_font_init_func_t</span></a>
93 </td>
94 <td class="function_name">
95 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-get-init-func" title="cairo_user_font_face_get_init_func ()">cairo_user_font_face_get_init_func</a> <span class="c_punctuation">()</span>
96 </td>
97 </tr>
98 <tr>
99 <td class="function_type">
100 <span class="returnvalue">void</span>
101 </td>
102 <td class="function_name">
103 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-set-render-glyph-func" title="cairo_user_font_face_set_render_glyph_func ()">cairo_user_font_face_set_render_glyph_func</a> <span class="c_punctuation">()</span>
104 </td>
105 </tr>
106 <tr>
107 <td class="function_type">
108 <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-render-glyph-func-t" title="cairo_user_scaled_font_render_glyph_func_t ()"><span class="returnvalue">cairo_user_scaled_font_render_glyph_func_t</span></a>
109 </td>
110 <td class="function_name">
111 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-get-render-glyph-func" title="cairo_user_font_face_get_render_glyph_func ()">cairo_user_font_face_get_render_glyph_func</a> <span class="c_punctuation">()</span>
112 </td>
113 </tr>
114 <tr>
115 <td class="function_type">
116 <span class="returnvalue">void</span>
117 </td>
118 <td class="function_name">
119 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-set-unicode-to-glyph-func" title="cairo_user_font_face_set_unicode_to_glyph_func ()">cairo_user_font_face_set_unicode_to_glyph_func</a> <span class="c_punctuation">()</span>
120 </td>
121 </tr>
122 <tr>
123 <td class="function_type">
124 <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()"><span class="returnvalue">cairo_user_scaled_font_unicode_to_glyph_func_t</span></a>
125 </td>
126 <td class="function_name">
127 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-get-unicode-to-glyph-func" title="cairo_user_font_face_get_unicode_to_glyph_func ()">cairo_user_font_face_get_unicode_to_glyph_func</a> <span class="c_punctuation">()</span>
128 </td>
129 </tr>
130 <tr>
131 <td class="function_type">
132 <span class="returnvalue">void</span>
133 </td>
134 <td class="function_name">
135 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-set-text-to-glyphs-func" title="cairo_user_font_face_set_text_to_glyphs_func ()">cairo_user_font_face_set_text_to_glyphs_func</a> <span class="c_punctuation">()</span>
136 </td>
137 </tr>
138 <tr>
139 <td class="function_type">
140 <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()"><span class="returnvalue">cairo_user_scaled_font_text_to_glyphs_func_t</span></a>
141 </td>
142 <td class="function_name">
143 <a class="link" href="cairo-User-Fonts.html#cairo-user-font-face-get-text-to-glyphs-func" title="cairo_user_font_face_get_text_to_glyphs_func ()">cairo_user_font_face_get_text_to_glyphs_func</a> <span class="c_punctuation">()</span>
144 </td>
145 </tr>
146 </tbody>
147 </table></div>
148 </div>
149 <div class="refsect1">
150 <a name="cairo-User-Fonts.other"></a><h2>Types and Values</h2>
151 <div class="informaltable"><table class="informaltable" width="100%" border="0">
152 <colgroup>
153 <col width="150px" class="name">
154 <col class="description">
155 </colgroup>
156 <tbody><tr>
157 <td class="define_keyword">#define</td>
158 <td class="function_name"><a class="link" href="cairo-User-Fonts.html#CAIRO-HAS-USER-FONT:CAPS" title="CAIRO_HAS_USER_FONT">CAIRO_HAS_USER_FONT</a></td>
159 </tr></tbody>
160 </table></div>
161 </div>
162 <div class="refsect1">
163 <a name="cairo-User-Fonts.description"></a><h2>Description</h2>
164 <p>The user-font feature allows the cairo user to provide drawings for glyphs
165 in a font. This is most useful in implementing fonts in non-standard
166 formats, like SVG fonts and Flash fonts, but can also be used by games and
167 other application to draw "funky" fonts.</p>
168 </div>
169 <div class="refsect1">
170 <a name="cairo-User-Fonts.functions_details"></a><h2>Functions</h2>
171 <div class="refsect2">
172 <a name="cairo-user-scaled-font-init-func-t"></a><h3>cairo_user_scaled_font_init_func_t ()</h3>
173 <pre class="programlisting"><a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
174 <span class="c_punctuation">(</span>*cairo_user_scaled_font_init_func_t<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="cairo-cairo-scaled-font-t.html#cairo-scaled-font-t" title="cairo_scaled_font_t"><span class="type">cairo_scaled_font_t</span></a> *scaled_font</code></em>,
175 <em class="parameter"><code><a class="link" href="cairo-cairo-t.html#cairo-t" title="cairo_t"><span class="type">cairo_t</span></a> *cr</code></em>,
176 <em class="parameter"><code><a class="link" href="cairo-cairo-scaled-font-t.html#cairo-font-extents-t" title="cairo_font_extents_t"><span class="type">cairo_font_extents_t</span></a> *extents</code></em>);</pre>
177 <p><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-init-func-t" title="cairo_user_scaled_font_init_func_t ()"><span class="type">cairo_user_scaled_font_init_func_t</span></a> is the type of function which is
178 called when a scaled-font needs to be created for a user font-face.</p>
179 <p>The cairo context <em class="parameter"><code>cr</code></em>
180 is not used by the caller, but is prepared in font
181 space, similar to what the cairo contexts passed to the render_glyph
182 method will look like. The callback can use this context for extents
183 computation for example. After the callback is called, <em class="parameter"><code>cr</code></em>
184 is checked
185 for any error status.</p>
186 <p>The <em class="parameter"><code>extents</code></em>
187 argument is where the user font sets the font extents for
188 <em class="parameter"><code>scaled_font</code></em>
189 . It is in font space, which means that for most cases its
190 ascent and descent members should add to 1.0. <em class="parameter"><code>extents</code></em>
191 is preset to
192 hold a value of 1.0 for ascent, height, and max_x_advance, and 0.0 for
193 descent and max_y_advance members.</p>
194 <p>The callback is optional. If not set, default font extents as described
195 in the previous paragraph will be used.</p>
196 <p>Note that <em class="parameter"><code>scaled_font</code></em>
197 is not fully initialized at this
198 point and trying to use it for text operations in the callback will result
199 in deadlock.</p>
200 <div class="refsect3">
201 <a name="cairo-user-scaled-font-init-func-t.parameters"></a><h4>Parameters</h4>
202 <div class="informaltable"><table class="informaltable" width="100%" border="0">
203 <colgroup>
204 <col width="150px" class="parameters_name">
205 <col class="parameters_description">
206 <col width="200px" class="parameters_annotations">
207 </colgroup>
208 <tbody>
209 <tr>
210 <td class="parameter_name"><p>scaled_font</p></td>
211 <td class="parameter_description"><p>the scaled-font being created</p></td>
212 <td class="parameter_annotations"> </td>
213 </tr>
214 <tr>
215 <td class="parameter_name"><p>cr</p></td>
216 <td class="parameter_description"><p>a cairo context, in font space</p></td>
217 <td class="parameter_annotations"> </td>
218 </tr>
219 <tr>
220 <td class="parameter_name"><p>extents</p></td>
221 <td class="parameter_description"><p>font extents to fill in, in font space</p></td>
222 <td class="parameter_annotations"> </td>
223 </tr>
224 </tbody>
225 </table></div>
226 </div>
227 <div class="refsect3">
228 <a name="cairo-user-scaled-font-init-func-t.returns"></a><h4>Returns</h4>
229 <p> <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-SUCCESS:CAPS"><code class="literal">CAIRO_STATUS_SUCCESS</code></a> upon success, or an error status on error.</p>
230 </div>
231 <p class="since">Since: 1.8</p>
232 </div>
233 <hr>
234 <div class="refsect2">
235 <a name="cairo-user-scaled-font-render-glyph-func-t"></a><h3>cairo_user_scaled_font_render_glyph_func_t ()</h3>
236 <pre class="programlisting"><a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
237 <span class="c_punctuation">(</span>*cairo_user_scaled_font_render_glyph_func_t<span class="c_punctuation">)</span>
238 (<em class="parameter"><code><a class="link" href="cairo-cairo-scaled-font-t.html#cairo-scaled-font-t" title="cairo_scaled_font_t"><span class="type">cairo_scaled_font_t</span></a> *scaled_font</code></em>,
239 <em class="parameter"><code><span class="type">unsigned long </span> glyph</code></em>,
240 <em class="parameter"><code><a class="link" href="cairo-cairo-t.html#cairo-t" title="cairo_t"><span class="type">cairo_t</span></a> *cr</code></em>,
241 <em class="parameter"><code><a class="link" href="cairo-cairo-scaled-font-t.html#cairo-text-extents-t" title="cairo_text_extents_t"><span class="type">cairo_text_extents_t</span></a> *extents</code></em>);</pre>
242 <p><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-render-glyph-func-t" title="cairo_user_scaled_font_render_glyph_func_t ()"><span class="type">cairo_user_scaled_font_render_glyph_func_t</span></a> is the type of function which
243 is called when a user scaled-font needs to render a glyph.</p>
244 <p>The callback is mandatory, and expected to draw the glyph with code <em class="parameter"><code>glyph</code></em>
245 to
246 the cairo context <em class="parameter"><code>cr</code></em>
247 . <em class="parameter"><code>cr</code></em>
248 is prepared such that the glyph drawing is done in
249 font space. That is, the matrix set on <em class="parameter"><code>cr</code></em>
250 is the scale matrix of <em class="parameter"><code>scaled_font</code></em>
251 ,
252 The <em class="parameter"><code>extents</code></em>
253 argument is where the user font sets the font extents for
254 <em class="parameter"><code>scaled_font</code></em>
255 . However, if user prefers to draw in user space, they can
256 achieve that by changing the matrix on <em class="parameter"><code>cr</code></em>
257 . All cairo rendering operations
258 to <em class="parameter"><code>cr</code></em>
259 are permitted, however, the result is undefined if any source other
260 than the default source on <em class="parameter"><code>cr</code></em>
261 is used. That means, glyph bitmaps should
262 be rendered using <a class="link" href="cairo-cairo-t.html#cairo-mask" title="cairo_mask ()"><code class="function">cairo_mask()</code></a> instead of <a class="link" href="cairo-cairo-t.html#cairo-paint" title="cairo_paint ()"><code class="function">cairo_paint()</code></a>.</p>
263 <p>Other non-default settings on <em class="parameter"><code>cr</code></em>
264 include a font size of 1.0 (given that
265 it is set up to be in font space), and font options corresponding to
266 <em class="parameter"><code>scaled_font</code></em>
267 .</p>
268 <p>The <em class="parameter"><code>extents</code></em>
269 argument is preset to have <code class="literal">x_bearing</code>,
270 <code class="literal">width</code>, and <code class="literal">y_advance</code> of zero,
271 <code class="literal">y_bearing</code> set to <code class="literal">-font_extents.ascent</code>,
272 <code class="literal">height</code> to <code class="literal">font_extents.ascent+font_extents.descent</code>,
273 and <code class="literal">x_advance</code> to <code class="literal">font_extents.max_x_advance</code>.
274 The only field user needs to set in majority of cases is
275 <code class="literal">x_advance</code>.
276 If the <code class="literal">width</code> field is zero upon the callback returning
277 (which is its preset value), the glyph extents are automatically computed
278 based on the drawings done to <em class="parameter"><code>cr</code></em>
279 . This is in most cases exactly what the
280 desired behavior is. However, if for any reason the callback sets the
281 extents, it must be ink extents, and include the extents of all drawing
282 done to <em class="parameter"><code>cr</code></em>
283 in the callback.</p>
284 <div class="refsect3">
285 <a name="cairo-user-scaled-font-render-glyph-func-t.parameters"></a><h4>Parameters</h4>
286 <div class="informaltable"><table class="informaltable" width="100%" border="0">
287 <colgroup>
288 <col width="150px" class="parameters_name">
289 <col class="parameters_description">
290 <col width="200px" class="parameters_annotations">
291 </colgroup>
292 <tbody>
293 <tr>
294 <td class="parameter_name"><p>scaled_font</p></td>
295 <td class="parameter_description"><p>user scaled-font</p></td>
296 <td class="parameter_annotations"> </td>
297 </tr>
298 <tr>
299 <td class="parameter_name"><p>glyph</p></td>
300 <td class="parameter_description"><p>glyph code to render</p></td>
301 <td class="parameter_annotations"> </td>
302 </tr>
303 <tr>
304 <td class="parameter_name"><p>cr</p></td>
305 <td class="parameter_description"><p>cairo context to draw to, in font space</p></td>
306 <td class="parameter_annotations"> </td>
307 </tr>
308 <tr>
309 <td class="parameter_name"><p>extents</p></td>
310 <td class="parameter_description"><p>glyph extents to fill in, in font space</p></td>
311 <td class="parameter_annotations"> </td>
312 </tr>
313 </tbody>
314 </table></div>
315 </div>
316 <div class="refsect3">
317 <a name="cairo-user-scaled-font-render-glyph-func-t.returns"></a><h4>Returns</h4>
318 <p> <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-SUCCESS:CAPS"><code class="literal">CAIRO_STATUS_SUCCESS</code></a> upon success, or
319 <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-ERROR:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_ERROR</code></a> or any other error status on error.</p>
320 </div>
321 <p class="since">Since: 1.8</p>
322 </div>
323 <hr>
324 <div class="refsect2">
325 <a name="cairo-user-scaled-font-text-to-glyphs-func-t"></a><h3>cairo_user_scaled_font_text_to_glyphs_func_t ()</h3>
326 <pre class="programlisting"><a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
327 <span class="c_punctuation">(</span>*cairo_user_scaled_font_text_to_glyphs_func_t<span class="c_punctuation">)</span>
328 (<em class="parameter"><code><a class="link" href="cairo-cairo-scaled-font-t.html#cairo-scaled-font-t" title="cairo_scaled_font_t"><span class="type">cairo_scaled_font_t</span></a> *scaled_font</code></em>,
329 <em class="parameter"><code>const <span class="type">char</span> *utf8</code></em>,
330 <em class="parameter"><code><span class="type">int</span> utf8_len</code></em>,
331 <em class="parameter"><code><a class="link" href="cairo-text.html#cairo-glyph-t" title="cairo_glyph_t"><span class="type">cairo_glyph_t</span></a> **glyphs</code></em>,
332 <em class="parameter"><code><span class="type">int</span> *num_glyphs</code></em>,
333 <em class="parameter"><code><a class="link" href="cairo-text.html#cairo-text-cluster-t" title="cairo_text_cluster_t"><span class="type">cairo_text_cluster_t</span></a> **clusters</code></em>,
334 <em class="parameter"><code><span class="type">int</span> *num_clusters</code></em>,
335 <em class="parameter"><code><a class="link" href="cairo-text.html#cairo-text-cluster-flags-t" title="enum cairo_text_cluster_flags_t"><span class="type">cairo_text_cluster_flags_t</span></a> *cluster_flags</code></em>);</pre>
336 <p><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()"><span class="type">cairo_user_scaled_font_text_to_glyphs_func_t</span></a> is the type of function which
337 is called to convert input text to an array of glyphs. This is used by the
338 <a class="link" href="cairo-text.html#cairo-show-text" title="cairo_show_text ()"><code class="function">cairo_show_text()</code></a> operation.</p>
339 <p>Using this callback the user-font has full control on glyphs and their
340 positions. That means, it allows for features like ligatures and kerning,
341 as well as complex <em class="firstterm">shaping</em> required for scripts like
342 Arabic and Indic.</p>
343 <p>The <em class="parameter"><code>num_glyphs</code></em>
344 argument is preset to the number of glyph entries available
345 in the <em class="parameter"><code>glyphs</code></em>
346 buffer. If the <em class="parameter"><code>glyphs</code></em>
347 buffer is <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a>, the value of
348 <em class="parameter"><code>num_glyphs</code></em>
349 will be zero. If the provided glyph array is too short for
350 the conversion (or for convenience), a new glyph array may be allocated
351 using <a class="link" href="cairo-text.html#cairo-glyph-allocate" title="cairo_glyph_allocate ()"><code class="function">cairo_glyph_allocate()</code></a> and placed in <em class="parameter"><code>glyphs</code></em>
352 . Upon return,
353 <em class="parameter"><code>num_glyphs</code></em>
354 should contain the number of generated glyphs. If the value
355 <em class="parameter"><code>glyphs</code></em>
356 points at has changed after the call, the caller will free the
357 allocated glyph array using <a class="link" href="cairo-text.html#cairo-glyph-free" title="cairo_glyph_free ()"><code class="function">cairo_glyph_free()</code></a>. The caller will also free
358 the original value of <em class="parameter"><code>glyphs</code></em>
359 , so the callback shouldn't do so.
360 The callback should populate the glyph indices and positions (in font space)
361 assuming that the text is to be shown at the origin.</p>
362 <p>If <em class="parameter"><code>clusters</code></em>
363 is not <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a>, <em class="parameter"><code>num_clusters</code></em>
364 and <em class="parameter"><code>cluster_flags</code></em>
365 are also
366 non-<a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a>, and cluster mapping should be computed. The semantics of how
367 cluster array allocation works is similar to the glyph array. That is,
368 if <em class="parameter"><code>clusters</code></em>
369 initially points to a non-<a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> value, that array may be used
370 as a cluster buffer, and <em class="parameter"><code>num_clusters</code></em>
371 points to the number of cluster
372 entries available there. If the provided cluster array is too short for
373 the conversion (or for convenience), a new cluster array may be allocated
374 using <a class="link" href="cairo-text.html#cairo-text-cluster-allocate" title="cairo_text_cluster_allocate ()"><code class="function">cairo_text_cluster_allocate()</code></a> and placed in <em class="parameter"><code>clusters</code></em>
375 . In this case,
376 the original value of <em class="parameter"><code>clusters</code></em>
377 will still be freed by the caller. Upon
378 return, <em class="parameter"><code>num_clusters</code></em>
379 should contain the number of generated clusters.
380 If the value <em class="parameter"><code>clusters</code></em>
381 points at has changed after the call, the caller
382 will free the allocated cluster array using <a class="link" href="cairo-text.html#cairo-text-cluster-free" title="cairo_text_cluster_free ()"><code class="function">cairo_text_cluster_free()</code></a>.</p>
383 <p>The callback is optional. If <em class="parameter"><code>num_glyphs</code></em>
384 is negative upon
385 the callback returning or if the return value
386 is <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-NOT-IMPLEMENTED:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED</code></a>, the unicode_to_glyph callback
387 is tried. See <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()"><span class="type">cairo_user_scaled_font_unicode_to_glyph_func_t</span></a>.</p>
388 <p>Note: While cairo does not impose any limitation on glyph indices,
389 some applications may assume that a glyph index fits in a 16-bit
390 unsigned integer. As such, it is advised that user-fonts keep their
391 glyphs in the 0 to 65535 range. Furthermore, some applications may
392 assume that glyph 0 is a special glyph-not-found glyph. User-fonts
393 are advised to use glyph 0 for such purposes and do not use that
394 glyph value for other purposes.</p>
395 <div class="refsect3">
396 <a name="cairo-user-scaled-font-text-to-glyphs-func-t.parameters"></a><h4>Parameters</h4>
397 <div class="informaltable"><table class="informaltable" width="100%" border="0">
398 <colgroup>
399 <col width="150px" class="parameters_name">
400 <col class="parameters_description">
401 <col width="200px" class="parameters_annotations">
402 </colgroup>
403 <tbody>
404 <tr>
405 <td class="parameter_name"><p>scaled_font</p></td>
406 <td class="parameter_description"><p>the scaled-font being created</p></td>
407 <td class="parameter_annotations"> </td>
408 </tr>
409 <tr>
410 <td class="parameter_name"><p>utf8</p></td>
411 <td class="parameter_description"><p>a string of text encoded in UTF-8</p></td>
412 <td class="parameter_annotations"> </td>
413 </tr>
414 <tr>
415 <td class="parameter_name"><p>utf8_len</p></td>
416 <td class="parameter_description"><p>length of <em class="parameter"><code>utf8</code></em>
417 in bytes</p></td>
418 <td class="parameter_annotations"> </td>
419 </tr>
420 <tr>
421 <td class="parameter_name"><p>glyphs</p></td>
422 <td class="parameter_description"><p>pointer to array of glyphs to fill, in font space</p></td>
423 <td class="parameter_annotations"> </td>
424 </tr>
425 <tr>
426 <td class="parameter_name"><p>num_glyphs</p></td>
427 <td class="parameter_description"><p>pointer to number of glyphs</p></td>
428 <td class="parameter_annotations"> </td>
429 </tr>
430 <tr>
431 <td class="parameter_name"><p>clusters</p></td>
432 <td class="parameter_description"><p>pointer to array of cluster mapping information to fill, or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a></p></td>
433 <td class="parameter_annotations"> </td>
434 </tr>
435 <tr>
436 <td class="parameter_name"><p>num_clusters</p></td>
437 <td class="parameter_description"><p>pointer to number of clusters</p></td>
438 <td class="parameter_annotations"> </td>
439 </tr>
440 <tr>
441 <td class="parameter_name"><p>cluster_flags</p></td>
442 <td class="parameter_description"><p>pointer to location to store cluster flags corresponding to the
443 output <em class="parameter"><code>clusters</code></em>
444 </p></td>
445 <td class="parameter_annotations"> </td>
446 </tr>
447 </tbody>
448 </table></div>
449 </div>
450 <div class="refsect3">
451 <a name="cairo-user-scaled-font-text-to-glyphs-func-t.returns"></a><h4>Returns</h4>
452 <p> <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-SUCCESS:CAPS"><code class="literal">CAIRO_STATUS_SUCCESS</code></a> upon success,
453 <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-NOT-IMPLEMENTED:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED</code></a> if fallback options should be tried,
454 or <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-ERROR:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_ERROR</code></a> or any other error status on error.</p>
455 </div>
456 <p class="since">Since: 1.8</p>
457 </div>
458 <hr>
459 <div class="refsect2">
460 <a name="cairo-user-scaled-font-unicode-to-glyph-func-t"></a><h3>cairo_user_scaled_font_unicode_to_glyph_func_t ()</h3>
461 <pre class="programlisting"><a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
462 <span class="c_punctuation">(</span>*cairo_user_scaled_font_unicode_to_glyph_func_t<span class="c_punctuation">)</span>
463 (<em class="parameter"><code><a class="link" href="cairo-cairo-scaled-font-t.html#cairo-scaled-font-t" title="cairo_scaled_font_t"><span class="type">cairo_scaled_font_t</span></a> *scaled_font</code></em>,
464 <em class="parameter"><code><span class="type">unsigned long </span> unicode</code></em>,
465 <em class="parameter"><code>unsigned <span class="type">long</span> *glyph_index</code></em>);</pre>
466 <p><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()"><span class="type">cairo_user_scaled_font_unicode_to_glyph_func_t</span></a> is the type of function which
467 is called to convert an input Unicode character to a single glyph.
468 This is used by the <a class="link" href="cairo-text.html#cairo-show-text" title="cairo_show_text ()"><code class="function">cairo_show_text()</code></a> operation.</p>
469 <p>This callback is used to provide the same functionality as the
470 text_to_glyphs callback does (see <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()"><span class="type">cairo_user_scaled_font_text_to_glyphs_func_t</span></a>)
471 but has much less control on the output,
472 in exchange for increased ease of use. The inherent assumption to using
473 this callback is that each character maps to one glyph, and that the
474 mapping is context independent. It also assumes that glyphs are positioned
475 according to their advance width. These mean no ligatures, kerning, or
476 complex scripts can be implemented using this callback.</p>
477 <p>The callback is optional, and only used if text_to_glyphs callback is not
478 set or fails to return glyphs. If this callback is not set or if it returns
479 <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-NOT-IMPLEMENTED:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED</code></a>, an identity mapping from Unicode
480 code-points to glyph indices is assumed.</p>
481 <p>Note: While cairo does not impose any limitation on glyph indices,
482 some applications may assume that a glyph index fits in a 16-bit
483 unsigned integer. As such, it is advised that user-fonts keep their
484 glyphs in the 0 to 65535 range. Furthermore, some applications may
485 assume that glyph 0 is a special glyph-not-found glyph. User-fonts
486 are advised to use glyph 0 for such purposes and do not use that
487 glyph value for other purposes.</p>
488 <div class="refsect3">
489 <a name="cairo-user-scaled-font-unicode-to-glyph-func-t.parameters"></a><h4>Parameters</h4>
490 <div class="informaltable"><table class="informaltable" width="100%" border="0">
491 <colgroup>
492 <col width="150px" class="parameters_name">
493 <col class="parameters_description">
494 <col width="200px" class="parameters_annotations">
495 </colgroup>
496 <tbody>
497 <tr>
498 <td class="parameter_name"><p>scaled_font</p></td>
499 <td class="parameter_description"><p>the scaled-font being created</p></td>
500 <td class="parameter_annotations"> </td>
501 </tr>
502 <tr>
503 <td class="parameter_name"><p>unicode</p></td>
504 <td class="parameter_description"><p>input unicode character code-point</p></td>
505 <td class="parameter_annotations"> </td>
506 </tr>
507 <tr>
508 <td class="parameter_name"><p>glyph_index</p></td>
509 <td class="parameter_description"><p>output glyph index</p></td>
510 <td class="parameter_annotations"> </td>
511 </tr>
512 </tbody>
513 </table></div>
514 </div>
515 <div class="refsect3">
516 <a name="cairo-user-scaled-font-unicode-to-glyph-func-t.returns"></a><h4>Returns</h4>
517 <p> <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-SUCCESS:CAPS"><code class="literal">CAIRO_STATUS_SUCCESS</code></a> upon success,
518 <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-NOT-IMPLEMENTED:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED</code></a> if fallback options should be tried,
519 or <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-ERROR:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_ERROR</code></a> or any other error status on error.</p>
520 </div>
521 <p class="since">Since: 1.8</p>
522 </div>
523 <hr>
524 <div class="refsect2">
525 <a name="cairo-user-font-face-create"></a><h3>cairo_user_font_face_create ()</h3>
526 <pre class="programlisting"><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="returnvalue">cairo_font_face_t</span></a> *
527 cairo_user_font_face_create (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
528 <p>Creates a new user font-face.</p>
529 <p>Use the setter functions to associate callbacks with the returned
530 user font. The only mandatory callback is render_glyph.</p>
531 <p>After the font-face is created, the user can attach arbitrary data
532 (the actual font data) to it using <a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-set-user-data" title="cairo_font_face_set_user_data ()"><code class="function">cairo_font_face_set_user_data()</code></a>
533 and access it from the user-font callbacks by using
534 <a class="link" href="cairo-cairo-scaled-font-t.html#cairo-scaled-font-get-font-face" title="cairo_scaled_font_get_font_face ()"><code class="function">cairo_scaled_font_get_font_face()</code></a> followed by
535 <a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-get-user-data" title="cairo_font_face_get_user_data ()"><code class="function">cairo_font_face_get_user_data()</code></a>.</p>
536 <div class="refsect3">
537 <a name="cairo-user-font-face-create.returns"></a><h4>Returns</h4>
538 <p> a newly created <a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a>. Free with
539 <a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-destroy" title="cairo_font_face_destroy ()"><code class="function">cairo_font_face_destroy()</code></a> when you are done using it.</p>
540 </div>
541 <p class="since">Since: 1.8</p>
542 </div>
543 <hr>
544 <div class="refsect2">
545 <a name="cairo-user-font-face-set-init-func"></a><h3>cairo_user_font_face_set_init_func ()</h3>
546 <pre class="programlisting"><span class="returnvalue">void</span>
547 cairo_user_font_face_set_init_func (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>,
548 <em class="parameter"><code><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-init-func-t" title="cairo_user_scaled_font_init_func_t ()"><span class="type">cairo_user_scaled_font_init_func_t</span></a> init_func</code></em>);</pre>
549 <p>Sets the scaled-font initialization function of a user-font.
550 See <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-init-func-t" title="cairo_user_scaled_font_init_func_t ()"><span class="type">cairo_user_scaled_font_init_func_t</span></a> for details of how the callback
551 works.</p>
552 <p>The font-face should not be immutable or a <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-IMMUTABLE:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_IMMUTABLE</code></a>
553 error will occur. A user font-face is immutable as soon as a scaled-font
554 is created from it.</p>
555 <div class="refsect3">
556 <a name="cairo-user-font-face-set-init-func.parameters"></a><h4>Parameters</h4>
557 <div class="informaltable"><table class="informaltable" width="100%" border="0">
558 <colgroup>
559 <col width="150px" class="parameters_name">
560 <col class="parameters_description">
561 <col width="200px" class="parameters_annotations">
562 </colgroup>
563 <tbody>
564 <tr>
565 <td class="parameter_name"><p>font_face</p></td>
566 <td class="parameter_description"><p>A user font face</p></td>
567 <td class="parameter_annotations"> </td>
568 </tr>
569 <tr>
570 <td class="parameter_name"><p>init_func</p></td>
571 <td class="parameter_description"><p>The init callback, or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a></p></td>
572 <td class="parameter_annotations"> </td>
573 </tr>
574 </tbody>
575 </table></div>
576 </div>
577 <p class="since">Since: 1.8</p>
578 </div>
579 <hr>
580 <div class="refsect2">
581 <a name="cairo-user-font-face-get-init-func"></a><h3>cairo_user_font_face_get_init_func ()</h3>
582 <pre class="programlisting"><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-init-func-t" title="cairo_user_scaled_font_init_func_t ()"><span class="returnvalue">cairo_user_scaled_font_init_func_t</span></a>
583 cairo_user_font_face_get_init_func (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>);</pre>
584 <p>Gets the scaled-font initialization function of a user-font.</p>
585 <div class="refsect3">
586 <a name="cairo-user-font-face-get-init-func.parameters"></a><h4>Parameters</h4>
587 <div class="informaltable"><table class="informaltable" width="100%" border="0">
588 <colgroup>
589 <col width="150px" class="parameters_name">
590 <col class="parameters_description">
591 <col width="200px" class="parameters_annotations">
592 </colgroup>
593 <tbody><tr>
594 <td class="parameter_name"><p>font_face</p></td>
595 <td class="parameter_description"><p>A user font face</p></td>
596 <td class="parameter_annotations"> </td>
597 </tr></tbody>
598 </table></div>
599 </div>
600 <div class="refsect3">
601 <a name="cairo-user-font-face-get-init-func.returns"></a><h4>Returns</h4>
602 <p> The init callback of <em class="parameter"><code>font_face</code></em>
603 or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> if none set or an error has occurred.</p>
604 </div>
605 <p class="since">Since: 1.8</p>
606 </div>
607 <hr>
608 <div class="refsect2">
609 <a name="cairo-user-font-face-set-render-glyph-func"></a><h3>cairo_user_font_face_set_render_glyph_func ()</h3>
610 <pre class="programlisting"><span class="returnvalue">void</span>
611 cairo_user_font_face_set_render_glyph_func
612 (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>,
613 <em class="parameter"><code><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-render-glyph-func-t" title="cairo_user_scaled_font_render_glyph_func_t ()"><span class="type">cairo_user_scaled_font_render_glyph_func_t</span></a> render_glyph_func</code></em>);</pre>
614 <p>Sets the glyph rendering function of a user-font.
615 See <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-render-glyph-func-t" title="cairo_user_scaled_font_render_glyph_func_t ()"><span class="type">cairo_user_scaled_font_render_glyph_func_t</span></a> for details of how the callback
616 works.</p>
617 <p>The font-face should not be immutable or a <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-IMMUTABLE:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_IMMUTABLE</code></a>
618 error will occur. A user font-face is immutable as soon as a scaled-font
619 is created from it.</p>
620 <p>The render_glyph callback is the only mandatory callback of a user-font.
621 If the callback is <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> and a glyph is tried to be rendered using
622 <em class="parameter"><code>font_face</code></em>
623 , a <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-ERROR:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_ERROR</code></a> will occur.</p>
624 <div class="refsect3">
625 <a name="cairo-user-font-face-set-render-glyph-func.parameters"></a><h4>Parameters</h4>
626 <div class="informaltable"><table class="informaltable" width="100%" border="0">
627 <colgroup>
628 <col width="150px" class="parameters_name">
629 <col class="parameters_description">
630 <col width="200px" class="parameters_annotations">
631 </colgroup>
632 <tbody>
633 <tr>
634 <td class="parameter_name"><p>font_face</p></td>
635 <td class="parameter_description"><p>A user font face</p></td>
636 <td class="parameter_annotations"> </td>
637 </tr>
638 <tr>
639 <td class="parameter_name"><p>render_glyph_func</p></td>
640 <td class="parameter_description"><p>The render_glyph callback, or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a></p></td>
641 <td class="parameter_annotations"> </td>
642 </tr>
643 </tbody>
644 </table></div>
645 </div>
646 <p class="since">Since: 1.8</p>
647 </div>
648 <hr>
649 <div class="refsect2">
650 <a name="cairo-user-font-face-get-render-glyph-func"></a><h3>cairo_user_font_face_get_render_glyph_func ()</h3>
651 <pre class="programlisting"><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-render-glyph-func-t" title="cairo_user_scaled_font_render_glyph_func_t ()"><span class="returnvalue">cairo_user_scaled_font_render_glyph_func_t</span></a>
652 cairo_user_font_face_get_render_glyph_func
653 (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>);</pre>
654 <p>Gets the glyph rendering function of a user-font.</p>
655 <div class="refsect3">
656 <a name="cairo-user-font-face-get-render-glyph-func.parameters"></a><h4>Parameters</h4>
657 <div class="informaltable"><table class="informaltable" width="100%" border="0">
658 <colgroup>
659 <col width="150px" class="parameters_name">
660 <col class="parameters_description">
661 <col width="200px" class="parameters_annotations">
662 </colgroup>
663 <tbody><tr>
664 <td class="parameter_name"><p>font_face</p></td>
665 <td class="parameter_description"><p>A user font face</p></td>
666 <td class="parameter_annotations"> </td>
667 </tr></tbody>
668 </table></div>
669 </div>
670 <div class="refsect3">
671 <a name="cairo-user-font-face-get-render-glyph-func.returns"></a><h4>Returns</h4>
672 <p> The render_glyph callback of <em class="parameter"><code>font_face</code></em>
673 or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> if none set or an error has occurred.</p>
674 </div>
675 <p class="since">Since: 1.8</p>
676 </div>
677 <hr>
678 <div class="refsect2">
679 <a name="cairo-user-font-face-set-unicode-to-glyph-func"></a><h3>cairo_user_font_face_set_unicode_to_glyph_func ()</h3>
680 <pre class="programlisting"><span class="returnvalue">void</span>
681 cairo_user_font_face_set_unicode_to_glyph_func
682 (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>,
683 <em class="parameter"><code><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()"><span class="type">cairo_user_scaled_font_unicode_to_glyph_func_t</span></a> unicode_to_glyph_func</code></em>);</pre>
684 <p>Sets the unicode-to-glyph conversion function of a user-font.
685 See <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()"><span class="type">cairo_user_scaled_font_unicode_to_glyph_func_t</span></a> for details of how the callback
686 works.</p>
687 <p>The font-face should not be immutable or a <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-IMMUTABLE:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_IMMUTABLE</code></a>
688 error will occur. A user font-face is immutable as soon as a scaled-font
689 is created from it.</p>
690 <div class="refsect3">
691 <a name="cairo-user-font-face-set-unicode-to-glyph-func.parameters"></a><h4>Parameters</h4>
692 <div class="informaltable"><table class="informaltable" width="100%" border="0">
693 <colgroup>
694 <col width="150px" class="parameters_name">
695 <col class="parameters_description">
696 <col width="200px" class="parameters_annotations">
697 </colgroup>
698 <tbody>
699 <tr>
700 <td class="parameter_name"><p>font_face</p></td>
701 <td class="parameter_description"><p>A user font face</p></td>
702 <td class="parameter_annotations"> </td>
703 </tr>
704 <tr>
705 <td class="parameter_name"><p>unicode_to_glyph_func</p></td>
706 <td class="parameter_description"><p>The unicode_to_glyph callback, or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a></p></td>
707 <td class="parameter_annotations"> </td>
708 </tr>
709 </tbody>
710 </table></div>
711 </div>
712 <p class="since">Since: 1.8</p>
713 </div>
714 <hr>
715 <div class="refsect2">
716 <a name="cairo-user-font-face-get-unicode-to-glyph-func"></a><h3>cairo_user_font_face_get_unicode_to_glyph_func ()</h3>
717 <pre class="programlisting"><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-unicode-to-glyph-func-t" title="cairo_user_scaled_font_unicode_to_glyph_func_t ()"><span class="returnvalue">cairo_user_scaled_font_unicode_to_glyph_func_t</span></a>
718 cairo_user_font_face_get_unicode_to_glyph_func
719 (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>);</pre>
720 <p>Gets the unicode-to-glyph conversion function of a user-font.</p>
721 <div class="refsect3">
722 <a name="cairo-user-font-face-get-unicode-to-glyph-func.parameters"></a><h4>Parameters</h4>
723 <div class="informaltable"><table class="informaltable" width="100%" border="0">
724 <colgroup>
725 <col width="150px" class="parameters_name">
726 <col class="parameters_description">
727 <col width="200px" class="parameters_annotations">
728 </colgroup>
729 <tbody><tr>
730 <td class="parameter_name"><p>font_face</p></td>
731 <td class="parameter_description"><p>A user font face</p></td>
732 <td class="parameter_annotations"> </td>
733 </tr></tbody>
734 </table></div>
735 </div>
736 <div class="refsect3">
737 <a name="cairo-user-font-face-get-unicode-to-glyph-func.returns"></a><h4>Returns</h4>
738 <p> The unicode_to_glyph callback of <em class="parameter"><code>font_face</code></em>
739 or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> if none set or an error occurred.</p>
740 </div>
741 <p class="since">Since: 1.8</p>
742 </div>
743 <hr>
744 <div class="refsect2">
745 <a name="cairo-user-font-face-set-text-to-glyphs-func"></a><h3>cairo_user_font_face_set_text_to_glyphs_func ()</h3>
746 <pre class="programlisting"><span class="returnvalue">void</span>
747 cairo_user_font_face_set_text_to_glyphs_func
748 (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>,
749 <em class="parameter"><code><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()"><span class="type">cairo_user_scaled_font_text_to_glyphs_func_t</span></a> text_to_glyphs_func</code></em>);</pre>
750 <p>Sets th text-to-glyphs conversion function of a user-font.
751 See <a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()"><span class="type">cairo_user_scaled_font_text_to_glyphs_func_t</span></a> for details of how the callback
752 works.</p>
753 <p>The font-face should not be immutable or a <a class="link" href="cairo-Error-handling.html#CAIRO-STATUS-USER-FONT-IMMUTABLE:CAPS"><code class="literal">CAIRO_STATUS_USER_FONT_IMMUTABLE</code></a>
754 error will occur. A user font-face is immutable as soon as a scaled-font
755 is created from it.</p>
756 <div class="refsect3">
757 <a name="cairo-user-font-face-set-text-to-glyphs-func.parameters"></a><h4>Parameters</h4>
758 <div class="informaltable"><table class="informaltable" width="100%" border="0">
759 <colgroup>
760 <col width="150px" class="parameters_name">
761 <col class="parameters_description">
762 <col width="200px" class="parameters_annotations">
763 </colgroup>
764 <tbody>
765 <tr>
766 <td class="parameter_name"><p>font_face</p></td>
767 <td class="parameter_description"><p>A user font face</p></td>
768 <td class="parameter_annotations"> </td>
769 </tr>
770 <tr>
771 <td class="parameter_name"><p>text_to_glyphs_func</p></td>
772 <td class="parameter_description"><p>The text_to_glyphs callback, or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a></p></td>
773 <td class="parameter_annotations"> </td>
774 </tr>
775 </tbody>
776 </table></div>
777 </div>
778 <p class="since">Since: 1.8</p>
779 </div>
780 <hr>
781 <div class="refsect2">
782 <a name="cairo-user-font-face-get-text-to-glyphs-func"></a><h3>cairo_user_font_face_get_text_to_glyphs_func ()</h3>
783 <pre class="programlisting"><a class="link" href="cairo-User-Fonts.html#cairo-user-scaled-font-text-to-glyphs-func-t" title="cairo_user_scaled_font_text_to_glyphs_func_t ()"><span class="returnvalue">cairo_user_scaled_font_text_to_glyphs_func_t</span></a>
784 cairo_user_font_face_get_text_to_glyphs_func
785 (<em class="parameter"><code><a class="link" href="cairo-cairo-font-face-t.html#cairo-font-face-t" title="cairo_font_face_t"><span class="type">cairo_font_face_t</span></a> *font_face</code></em>);</pre>
786 <p>Gets the text-to-glyphs conversion function of a user-font.</p>
787 <div class="refsect3">
788 <a name="cairo-user-font-face-get-text-to-glyphs-func.parameters"></a><h4>Parameters</h4>
789 <div class="informaltable"><table class="informaltable" width="100%" border="0">
790 <colgroup>
791 <col width="150px" class="parameters_name">
792 <col class="parameters_description">
793 <col width="200px" class="parameters_annotations">
794 </colgroup>
795 <tbody><tr>
796 <td class="parameter_name"><p>font_face</p></td>
797 <td class="parameter_description"><p>A user font face</p></td>
798 <td class="parameter_annotations"> </td>
799 </tr></tbody>
800 </table></div>
801 </div>
802 <div class="refsect3">
803 <a name="cairo-user-font-face-get-text-to-glyphs-func.returns"></a><h4>Returns</h4>
804 <p> The text_to_glyphs callback of <em class="parameter"><code>font_face</code></em>
805 or <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> if none set or an error occurred.</p>
806 </div>
807 <p class="since">Since: 1.8</p>
808 </div>
809 </div>
810 <div class="refsect1">
811 <a name="cairo-User-Fonts.other_details"></a><h2>Types and Values</h2>
812 <div class="refsect2">
813 <a name="CAIRO-HAS-USER-FONT:CAPS"></a><h3>CAIRO_HAS_USER_FONT</h3>
814 <pre class="programlisting">#define CAIRO_HAS_USER_FONT 1
815 </pre>
816 <p>Defined if the user font backend is available.
817 This macro can be used to conditionally compile backend-specific code.
818 The user font backend is always built in versions of cairo that support
819 this feature (1.8 and later).</p>
820 <p class="since">Since: 1.8</p>
821 </div>
822 </div>
823 </div>
824 <div class="footer">
825 <hr>Generated by GTK-Doc V1.27</div>
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