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<span id="g_t9_002dPatches"></span><div class="header">
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Next: <a href="Fonts.html" accesskey="n" rel="next">Fonts</a>, Previous: <a href="Sprites.html" accesskey="p" rel="prev">Sprites</a>, Up: <a href="Graphics.html" accesskey="u" rel="up">Graphics</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html" title="Index" rel="index">Index</a>]</p>
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<hr>
<span id="g_t9_002dPatches-1"></span><h4 class="subsection">2.3.4 9-Patches</h4>

<p>A 9-patch is a method of rendering a texture so that it can be
stretched to cover an area of any size without becoming distorted.
This is achieved by dividing up the sprite into nine regions:
</p>
<ul>
<li> the center, which can be stretched or tiled horizontally and vertically
</li><li> the four corners, which are never stretched or tiled
</li><li> the left and right sides, which can be stretched or tiled vertically
</li><li> the top and bottom sides, which can be stretched or tiled horizontally
</li></ul>

<p>The most common application of this technique is for graphical user
interface widgets like buttons and dialog boxes which are often
dynamically resizable.  By using a 9-patch, they can be rendered at
any size without scaling artifacts.
</p>
<dl>
<dt id="index-draw_002dnine_002dpatch">Procedure: <strong>draw-nine-patch</strong> <em>texture rect        [#:margin 0] [#:top-margin margin] [#:bottom-margin margin]        [#:left-margin margin] [#:right-margin margin] [#:mode stretch]        [#:origin] [#:scale] [#:rotation] [#:blend-mode]        [#:tint white]</em></dt>
<dd>
<p>Draw a 9-patch over the area <var>rect</var> using <var>texture</var> whose
stretchable/tileable patches are defined by the given margin
measurements.  The corners are never stretched/tiled, the left and
right edges will be stretched/tiled vertically, the top and bottom
edges may be stretched/tiled horizontally, and the center may be
stretched/tiled in both directions.
</p>
<p><var>mode</var> may be either <code>stretch</code> (the default) or <code>tile</code>.
</p>
<p><var>margin</var> specifies the margin size for all sides of the 9-patch.
To make margins of differing sizes, the <var>top-margin</var>,
<var>bottom-margin</var>, <var>left-margin</var>, and <var>right-margin</var>
arguments may be used.
</p>
<p>Refer to <code>draw-sprite</code> (see <a href="Sprites.html">Sprites</a>) for information about
the other arguments as they are the same.
</p></dd></dl>




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