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<a name="cairo-Raster-Sources"></a><div class="titlepage"></div>
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<td valign="top">
<h2><span class="refentrytitle"><a name="cairo-Raster-Sources.top_of_page"></a>Raster Sources</span></h2>
<p>Raster Sources — Supplying arbitrary image data</p>
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<div class="refsect1">
<a name="cairo-Raster-Sources.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="returnvalue">cairo_pattern_t</span></a> *
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-pattern-create-raster-source" title="cairo_pattern_create_raster_source ()">cairo_pattern_create_raster_source</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-set-callback-data" title="cairo_raster_source_pattern_set_callback_data ()">cairo_raster_source_pattern_set_callback_data</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span> *
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-get-callback-data" title="cairo_raster_source_pattern_get_callback_data ()">cairo_raster_source_pattern_get_callback_data</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-set-acquire" title="cairo_raster_source_pattern_set_acquire ()">cairo_raster_source_pattern_set_acquire</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-get-acquire" title="cairo_raster_source_pattern_get_acquire ()">cairo_raster_source_pattern_get_acquire</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-set-snapshot" title="cairo_raster_source_pattern_set_snapshot ()">cairo_raster_source_pattern_set_snapshot</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-snapshot-func-t" title="cairo_raster_source_snapshot_func_t ()"><span class="returnvalue">cairo_raster_source_snapshot_func_t</span></a>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-get-snapshot" title="cairo_raster_source_pattern_get_snapshot ()">cairo_raster_source_pattern_get_snapshot</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-set-copy" title="cairo_raster_source_pattern_set_copy ()">cairo_raster_source_pattern_set_copy</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-copy-func-t" title="cairo_raster_source_copy_func_t ()"><span class="returnvalue">cairo_raster_source_copy_func_t</span></a>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-get-copy" title="cairo_raster_source_pattern_get_copy ()">cairo_raster_source_pattern_get_copy</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-set-finish" title="cairo_raster_source_pattern_set_finish ()">cairo_raster_source_pattern_set_finish</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-finish-func-t" title="cairo_raster_source_finish_func_t ()"><span class="returnvalue">cairo_raster_source_finish_func_t</span></a>
</td>
<td class="function_name">
<a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-pattern-get-finish" title="cairo_raster_source_pattern_get_finish ()">cairo_raster_source_pattern_get_finish</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="returnvalue">cairo_surface_t</span></a>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-acquire-func-t" title="cairo_raster_source_acquire_func_t ()">*cairo_raster_source_acquire_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-release-func-t" title="cairo_raster_source_release_func_t ()">*cairo_raster_source_release_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-snapshot-func-t" title="cairo_raster_source_snapshot_func_t ()">*cairo_raster_source_snapshot_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="returnvalue">cairo_status_t</span></a>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-copy-func-t" title="cairo_raster_source_copy_func_t ()">*cairo_raster_source_copy_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-finish-func-t" title="cairo_raster_source_finish_func_t ()">*cairo_raster_source_finish_func_t</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="cairo-Raster-Sources.description"></a><h2>Description</h2>
<p>The raster source provides the ability to supply arbitrary pixel data
whilst rendering. The pixels are queried at the time of rasterisation
by means of user callback functions, allowing for the ultimate
flexibility. For example, in handling compressed image sources, you
may keep a MRU cache of decompressed images and decompress sources on the
fly and discard old ones to conserve memory.</p>
<p>For the raster source to be effective, you must at least specify
the acquire and release callbacks which are used to retrieve the pixel
data for the region of interest and demark when it can be freed afterwards.
Other callbacks are provided for when the pattern is copied temporarily
during rasterisation, or more permanently as a snapshot in order to keep
the pixel data available for printing.</p>
</div>
<div class="refsect1">
<a name="cairo-Raster-Sources.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="cairo-pattern-create-raster-source"></a><h3>cairo_pattern_create_raster_source ()</h3>
<pre class="programlisting"><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="returnvalue">cairo_pattern_t</span></a> *
cairo_pattern_create_raster_source (<em class="parameter"><code><span class="type">void</span> *user_data</code></em>,
                                    <em class="parameter"><code><a class="link" href="cairo-cairo-surface-t.html#cairo-content-t" title="enum cairo_content_t"><span class="type">cairo_content_t</span></a> content</code></em>,
                                    <em class="parameter"><code><span class="type">int</span> width</code></em>,
                                    <em class="parameter"><code><span class="type">int</span> height</code></em>);</pre>
<p>Creates a new user pattern for providing pixel data.</p>
<p>Use the setter functions to associate callbacks with the returned
pattern.  The only mandatory callback is acquire.</p>
<div class="refsect3">
<a name="cairo-pattern-create-raster-source.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>user_data</p></td>
<td class="parameter_description"><p>the user data to be passed to all callbacks</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>content</p></td>
<td class="parameter_description"><p>content type for the pixel data that will be returned. Knowing
the content type ahead of time is used for analysing the operation and
picking the appropriate rendering path.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>width</p></td>
<td class="parameter_description"><p>maximum size of the sample area</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>height</p></td>
<td class="parameter_description"><p>maximum size of the sample area</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-pattern-create-raster-source.returns"></a><h4>Returns</h4>
<p> a newly created <a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a>. Free with
<a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-destroy" title="cairo_pattern_destroy ()"><code class="function">cairo_pattern_destroy()</code></a> when you are done using it.</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-set-callback-data"></a><h3>cairo_raster_source_pattern_set_callback_data ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
cairo_raster_source_pattern_set_callback_data
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                <em class="parameter"><code><span class="type">void</span> *data</code></em>);</pre>
<p>Updates the user data that is provided to all callbacks.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-set-callback-data.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to update</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>the user data to be passed to all callbacks</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-get-callback-data"></a><h3>cairo_raster_source_pattern_get_callback_data ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> *
cairo_raster_source_pattern_get_callback_data
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>);</pre>
<p>Queries the current user data.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-callback-data.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to update</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-callback-data.returns"></a><h4>Returns</h4>
<p> the current user-data passed to each callback</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-set-acquire"></a><h3>cairo_raster_source_pattern_set_acquire ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
cairo_raster_source_pattern_set_acquire
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-acquire-func-t" title="cairo_raster_source_acquire_func_t ()"><span class="type">cairo_raster_source_acquire_func_t</span></a> acquire</code></em>,
                                <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-release-func-t" title="cairo_raster_source_release_func_t ()"><span class="type">cairo_raster_source_release_func_t</span></a> release</code></em>);</pre>
<p>Specifies the callbacks used to generate the image surface for a rendering
operation (acquire) and the function used to cleanup that surface afterwards.</p>
<p>The <em class="parameter"><code>acquire</code></em>
 callback should create a surface (preferably an image
surface created to match the target using
<a class="link" href="cairo-cairo-surface-t.html#cairo-surface-create-similar-image" title="cairo_surface_create_similar_image ()"><code class="function">cairo_surface_create_similar_image()</code></a>) that defines at least the region
of interest specified by extents. The surface is allowed to be the entire
sample area, but if it does contain a subsection of the sample area,
the surface extents should be provided by setting the device offset (along
with its width and height) using <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-set-device-offset" title="cairo_surface_set_device_offset ()"><code class="function">cairo_surface_set_device_offset()</code></a>.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-set-acquire.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to update</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>acquire</p></td>
<td class="parameter_description"><p>acquire callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>release</p></td>
<td class="parameter_description"><p>release callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-get-acquire"></a><h3>cairo_raster_source_pattern_get_acquire ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
cairo_raster_source_pattern_get_acquire
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-acquire-func-t" title="cairo_raster_source_acquire_func_t ()"><span class="type">cairo_raster_source_acquire_func_t</span></a> *acquire</code></em>,
                                <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-release-func-t" title="cairo_raster_source_release_func_t ()"><span class="type">cairo_raster_source_release_func_t</span></a> *release</code></em>);</pre>
<p>Queries the current acquire and release callbacks.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-acquire.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to query</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>acquire</p></td>
<td class="parameter_description"><p>return value for the current acquire callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>release</p></td>
<td class="parameter_description"><p>return value for the current release callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-set-snapshot"></a><h3>cairo_raster_source_pattern_set_snapshot ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
cairo_raster_source_pattern_set_snapshot
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-snapshot-func-t" title="cairo_raster_source_snapshot_func_t ()"><span class="type">cairo_raster_source_snapshot_func_t</span></a> snapshot</code></em>);</pre>
<p>Sets the callback that will be used whenever a snapshot is taken of the
pattern, that is whenever the current contents of the pattern should be
preserved for later use. This is typically invoked whilst printing.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-set-snapshot.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to update</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>snapshot</p></td>
<td class="parameter_description"><p>snapshot callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-get-snapshot"></a><h3>cairo_raster_source_pattern_get_snapshot ()</h3>
<pre class="programlisting"><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-snapshot-func-t" title="cairo_raster_source_snapshot_func_t ()"><span class="returnvalue">cairo_raster_source_snapshot_func_t</span></a>
cairo_raster_source_pattern_get_snapshot
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>);</pre>
<p>Queries the current snapshot callback.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-snapshot.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to query</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-snapshot.returns"></a><h4>Returns</h4>
<p> the current snapshot callback</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-set-copy"></a><h3>cairo_raster_source_pattern_set_copy ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
cairo_raster_source_pattern_set_copy (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                      <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-copy-func-t" title="cairo_raster_source_copy_func_t ()"><span class="type">cairo_raster_source_copy_func_t</span></a> copy</code></em>);</pre>
<p>Updates the copy callback which is used whenever a temporary copy of the
pattern is taken.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-set-copy.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to update</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>copy</p></td>
<td class="parameter_description"><p>the copy callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-get-copy"></a><h3>cairo_raster_source_pattern_get_copy ()</h3>
<pre class="programlisting"><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-copy-func-t" title="cairo_raster_source_copy_func_t ()"><span class="returnvalue">cairo_raster_source_copy_func_t</span></a>
cairo_raster_source_pattern_get_copy (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>);</pre>
<p>Queries the current copy callback.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-copy.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to query</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-copy.returns"></a><h4>Returns</h4>
<p> the current copy callback</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-set-finish"></a><h3>cairo_raster_source_pattern_set_finish ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
cairo_raster_source_pattern_set_finish
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                <em class="parameter"><code><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-finish-func-t" title="cairo_raster_source_finish_func_t ()"><span class="type">cairo_raster_source_finish_func_t</span></a> finish</code></em>);</pre>
<p>Updates the finish callback which is used whenever a pattern (or a copy
thereof) will no longer be used.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-set-finish.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to update</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>finish</p></td>
<td class="parameter_description"><p>the finish callback</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-pattern-get-finish"></a><h3>cairo_raster_source_pattern_get_finish ()</h3>
<pre class="programlisting"><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-finish-func-t" title="cairo_raster_source_finish_func_t ()"><span class="returnvalue">cairo_raster_source_finish_func_t</span></a>
cairo_raster_source_pattern_get_finish
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>);</pre>
<p>Queries the current finish callback.</p>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-finish.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern to query</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-pattern-get-finish.returns"></a><h4>Returns</h4>
<p> the current finish callback</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-acquire-func-t"></a><h3>cairo_raster_source_acquire_func_t ()</h3>
<pre class="programlisting"><a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="returnvalue">cairo_surface_t</span></a>
<span class="c_punctuation">(</span>*cairo_raster_source_acquire_func_t<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                       <em class="parameter"><code><span class="type">void</span> *callback_data</code></em>,
                                       <em class="parameter"><code><a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="type">cairo_surface_t</span></a> *target</code></em>,
                                       <em class="parameter"><code>const <a class="link" href="cairo-Types.html#cairo-rectangle-int-t" title="cairo_rectangle_int_t"><span class="type">cairo_rectangle_int_t</span></a> *extents</code></em>);</pre>
<p><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-acquire-func-t" title="cairo_raster_source_acquire_func_t ()"><span class="type">cairo_raster_source_acquire_func_t</span></a> is the type of function which is
called when a pattern is being rendered from. It should create a surface
that provides the pixel data for the region of interest as defined by
extents, though the surface itself does not have to be limited to that
area. For convenience the surface should probably be of image type,
created with <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-create-similar-image" title="cairo_surface_create_similar_image ()"><code class="function">cairo_surface_create_similar_image()</code></a> for the target (which
enables the number of copies to be reduced during transfer to the
device). Another option, might be to return a similar surface to the
target for explicit handling by the application of a set of cached sources
on the device. The region of sample data provided should be defined using
<a class="link" href="cairo-cairo-surface-t.html#cairo-surface-set-device-offset" title="cairo_surface_set_device_offset ()"><code class="function">cairo_surface_set_device_offset()</code></a> to specify the top-left corner of the
sample data (along with width and height of the surface).</p>
<div class="refsect3">
<a name="cairo-raster-source-acquire-func-t.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern being rendered from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>callback_data</p></td>
<td class="parameter_description"><p>the user data supplied during creation</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>target</p></td>
<td class="parameter_description"><p>the rendering target surface</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>extents</p></td>
<td class="parameter_description"><p>rectangular region of interest in pixels in sample space</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-acquire-func-t.returns"></a><h4>Returns</h4>
<p> a <a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="type">cairo_surface_t</span></a></p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-release-func-t"></a><h3>cairo_raster_source_release_func_t ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
<span class="c_punctuation">(</span>*cairo_raster_source_release_func_t<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                       <em class="parameter"><code><span class="type">void</span> *callback_data</code></em>,
                                       <em class="parameter"><code><a class="link" href="cairo-cairo-surface-t.html#cairo-surface-t" title="cairo_surface_t"><span class="type">cairo_surface_t</span></a> *surface</code></em>);</pre>
<p><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-release-func-t" title="cairo_raster_source_release_func_t ()"><span class="type">cairo_raster_source_release_func_t</span></a> is the type of function which is
called when the pixel data is no longer being access by the pattern
for the rendering operation. Typically this function will simply
destroy the surface created during acquire.</p>
<div class="refsect3">
<a name="cairo-raster-source-release-func-t.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern being rendered from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>callback_data</p></td>
<td class="parameter_description"><p>the user data supplied during creation</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>surface</p></td>
<td class="parameter_description"><p>the surface created during acquire</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-snapshot-func-t"></a><h3>cairo_raster_source_snapshot_func_t ()</h3>
<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>
<span class="c_punctuation">(</span>*cairo_raster_source_snapshot_func_t<span class="c_punctuation">)</span>
                               (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                <em class="parameter"><code><span class="type">void</span> *callback_data</code></em>);</pre>
<p><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-snapshot-func-t" title="cairo_raster_source_snapshot_func_t ()"><span class="type">cairo_raster_source_snapshot_func_t</span></a> is the type of function which is
called when the pixel data needs to be preserved for later use
during printing. This pattern will be accessed again later, and it
is expected to provide the pixel data that was current at the time
of snapshotting.</p>
<div class="refsect3">
<a name="cairo-raster-source-snapshot-func-t.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern being rendered from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>callback_data</p></td>
<td class="parameter_description"><p>the user data supplied during creation</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-snapshot-func-t.returns"></a><h4>Returns</h4>
<p> CAIRO_STATUS_SUCCESS on success, or one of the
<a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="type">cairo_status_t</span></a> error codes for failure.</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-copy-func-t"></a><h3>cairo_raster_source_copy_func_t ()</h3>
<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>
<span class="c_punctuation">(</span>*cairo_raster_source_copy_func_t<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                    <em class="parameter"><code><span class="type">void</span> *callback_data</code></em>,
                                    <em class="parameter"><code>const <a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *other</code></em>);</pre>
<p><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-copy-func-t" title="cairo_raster_source_copy_func_t ()"><span class="type">cairo_raster_source_copy_func_t</span></a> is the type of function which is
called when the pattern gets copied as a normal part of rendering.</p>
<div class="refsect3">
<a name="cairo-raster-source-copy-func-t.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the <a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> that was copied to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>callback_data</p></td>
<td class="parameter_description"><p>the user data supplied during creation</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>other</p></td>
<td class="parameter_description"><p>the <a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> being used as the source for the copy</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="cairo-raster-source-copy-func-t.returns"></a><h4>Returns</h4>
<p> CAIRO_STATUS_SUCCESS on success, or one of the
<a class="link" href="cairo-Error-handling.html#cairo-status-t" title="enum cairo_status_t"><span class="type">cairo_status_t</span></a> error codes for failure.</p>
</div>
<p class="since">Since: 1.12</p>
</div>
<hr>
<div class="refsect2">
<a name="cairo-raster-source-finish-func-t"></a><h3>cairo_raster_source_finish_func_t ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
<span class="c_punctuation">(</span>*cairo_raster_source_finish_func_t<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a> *pattern</code></em>,
                                      <em class="parameter"><code><span class="type">void</span> *callback_data</code></em>);</pre>
<p><a class="link" href="cairo-Raster-Sources.html#cairo-raster-source-finish-func-t" title="cairo_raster_source_finish_func_t ()"><span class="type">cairo_raster_source_finish_func_t</span></a> is the type of function which is
called when the pattern (or a copy thereof) is no longer required.</p>
<div class="refsect3">
<a name="cairo-raster-source-finish-func-t.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>pattern</p></td>
<td class="parameter_description"><p>the pattern being rendered from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>callback_data</p></td>
<td class="parameter_description"><p>the user data supplied during creation</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: 1.12</p>
</div>
</div>
<div class="refsect1">
<a name="cairo-Raster-Sources.other_details"></a><h2>Types and Values</h2>
</div>
<div class="refsect1">
<a name="cairo-Raster-Sources.see-also"></a><h2>See Also</h2>
<p><a class="link" href="cairo-cairo-pattern-t.html#cairo-pattern-t" title="cairo_pattern_t"><span class="type">cairo_pattern_t</span></a></p>
</div>
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author	jpayne
date	Tue, 18 Mar 2025 16:23:26 -0400
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