skia2/site/user/api/SkAutoCanvasRestore_Reference.md

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SkAutoCanvasRestore Reference
===
<a name='SkAutoCanvasRestore'></a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
class <a href='SkAutoCanvasRestore_Reference#SkAutoCanvasRestore'>SkAutoCanvasRestore</a> {
<a href='#SkAutoCanvasRestore_SkCanvas_star'>SkAutoCanvasRestore</a>(<a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>* <a href='SkCanvas_Reference#Canvas'>canvas</a>, bool doSave);
<a href='#SkAutoCanvasRestore_destructor'>~SkAutoCanvasRestore()</a>;
void <a href='#SkAutoCanvasRestore_restore'>restore()</a>;
};
</pre>
Stack helper class calls <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_restoreToCount'>restoreToCount</a> when <a href='SkAutoCanvasRestore_Reference#SkAutoCanvasRestore'>SkAutoCanvasRestore</a>
goes out of scope. Use this to guarantee that the <a href='SkCanvas_Reference#Canvas'>canvas</a> is restored to a known
state.
<a name='SkAutoCanvasRestore_SkCanvas_star'></a>
---
<pre style="padding: 1em 1em 1em 1em; width: 62.5em;background-color: #f0f0f0">
<a href='#SkAutoCanvasRestore_SkCanvas_star'>SkAutoCanvasRestore</a>(<a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>* <a href='SkCanvas_Reference#Canvas'>canvas</a>, bool doSave)
</pre>
Preserves <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_save'>save()</a> count. Optionally saves <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a> clip and <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a> <a href='SkMatrix_Reference#Matrix'>matrix</a>.
### Parameters
<table> <tr> <td><a name='SkAutoCanvasRestore_SkCanvas_star_canvas'><code><strong>canvas</strong></code></a></td>
<td><a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a> to guard</td>
</tr>
<tr> <td><a name='SkAutoCanvasRestore_SkCanvas_star_doSave'><code><strong>doSave</strong></code></a></td>
<td>call <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_save'>save()</a></td>
</tr>
</table>
### Return Value
utility to restore <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a> state on destructor
### Example
<div><fiddle-embed name="466ef576b88e29d7252422db7adeed1c"></fiddle-embed></div>
### See Also
<a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_save'>save</a> <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_restore'>restore</a>
<a name='SkAutoCanvasRestore_destructor'></a>
---
<pre style="padding: 1em 1em 1em 1em; width: 62.5em;background-color: #f0f0f0">
<a href='#SkAutoCanvasRestore_destructor'>~SkAutoCanvasRestore()</a>
</pre>
Restores <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a> to saved state. Destructor is called when container goes out of
scope.
### See Also
<a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_save'>save</a> <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_restore'>restore</a>
<a name='SkAutoCanvasRestore_restore'></a>
---
<pre style="padding: 1em 1em 1em 1em; width: 62.5em;background-color: #f0f0f0">
void <a href='#SkAutoCanvasRestore_restore'>restore()</a>
</pre>
Restores <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a> to saved state immediately. Subsequent calls and
<a href='#SkAutoCanvasRestore_destructor'>~SkAutoCanvasRestore()</a> have no effect.
### Example
<div><fiddle-embed name="9f459b218ec079c1ada23f4412968f9a">
#### Example Output
~~~~
saveCanvas: false before restore: 2
saveCanvas: false after restore: 2
saveCanvas: true before restore: 2
saveCanvas: true after restore: 2
saveCanvas: false before restore: 2
saveCanvas: false after restore: 1
saveCanvas: true before restore: 2
saveCanvas: true after restore: 1
final count: 1
~~~~
</fiddle-embed></div>
### See Also
<a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_save'>save</a> <a href='SkCanvas_Reference#SkCanvas'>SkCanvas</a>::<a href='#SkCanvas_restore'>restore</a>