📄 function.imageantialias.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Should antialias functions be used or not</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.imagealphablending.html">imagealphablending</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.imagearc.html">imagearc</a></div> <div class="up"><a href="ref.image.html">GD Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.imageantialias" class="refentry"> <div class="refnamediv"> <h1 class="refname">imageantialias</h1> <p class="verinfo">(PHP 4 >= 4.3.2, PHP 5)</p><p class="refpurpose"><span class="refname">imageantialias</span> — <span class="dc-title">Should antialias functions be used or not</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">bool</span> <span class="methodname"><b><b>imageantialias</b></b></span> ( <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$image</tt></span> , <span class="methodparam"><span class="type">bool</span> <tt class="parameter">$enabled</tt></span> )</div> <p class="para rdfs-comment"> Activate the fast drawing antialiased methods for lines and wired polygons. It does not support alpha components. It works using a direct blend operation. It works only with truecolor images. </p> <p class="para"> Thickness and styled are not supported. </p> <p class="para"> Using antialiased primitives with transparent background color can end with some unexpected results. The blend method uses the background color as any other colors. The lack of alpha component support does not allow an alpha based antialiasing method. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt><span class="term"><i><tt class="parameter">image</tt></i></span><dd><p class="para">An image resource, returned by one of the image creation functions, such as <a href="function.imagecreatetruecolor.html" class="function">imagecreatetruecolor()</a>.</p></dd></dt> <dt> <span class="term"><i><tt class="parameter">enabled</tt></i></span> <dd> <p class="para"> Whether to enable antialiasing or not. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns <b><tt>TRUE</tt></b> on success or <b><tt>FALSE</tt></b> on failure. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 A comparison of two lines, one with anti-aliasing switched on</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Setup an anti-aliased image and a normal image<br /></span><span style="color: #0000BB">$aa </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecreatetruecolor</span><span style="color: #007700">(</span><span style="color: #0000BB">400</span><span style="color: #007700">, </span><span style="color: #0000BB">100</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$normal </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecreatetruecolor</span><span style="color: #007700">(</span><span style="color: #0000BB">200</span><span style="color: #007700">, </span><span style="color: #0000BB">100</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Switch antialiasing on for one image<br /></span><span style="color: #0000BB">imageantialias</span><span style="color: #007700">(</span><span style="color: #0000BB">$aa</span><span style="color: #007700">, </span><span style="color: #0000BB">true</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Allocate colors<br /></span><span style="color: #0000BB">$red </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecolorallocate</span><span style="color: #007700">(</span><span style="color: #0000BB">$normal</span><span style="color: #007700">, </span><span style="color: #0000BB">255</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$red_aa </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecolorallocate</span><span style="color: #007700">(</span><span style="color: #0000BB">$aa</span><span style="color: #007700">, </span><span style="color: #0000BB">255</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Draw two lines, one with AA enabled<br /></span><span style="color: #0000BB">imageline</span><span style="color: #007700">(</span><span style="color: #0000BB">$normal</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">200</span><span style="color: #007700">, </span><span style="color: #0000BB">100</span><span style="color: #007700">, </span><span style="color: #0000BB">$red</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">imageline</span><span style="color: #007700">(</span><span style="color: #0000BB">$aa</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">200</span><span style="color: #007700">, </span><span style="color: #0000BB">100</span><span style="color: #007700">, </span><span style="color: #0000BB">$red_aa</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Merge the two images side by side for output (AA: left, Normal: Right)<br /></span><span style="color: #0000BB">imagecopymerge</span><span style="color: #007700">(</span><span style="color: #0000BB">$aa</span><span style="color: #007700">, </span><span style="color: #0000BB">$normal</span><span style="color: #007700">, </span><span style="color: #0000BB">200</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">200</span><span style="color: #007700">, </span><span style="color: #0000BB">100</span><span style="color: #007700">, </span><span style="color: #0000BB">100</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Output image<br /></span><span style="color: #0000BB">header</span><span style="color: #007700">(</span><span style="color: #DD0000">'Content-type: image/png'</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">imagepng</span><span style="color: #007700">(</span><span style="color: #0000BB">$aa</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">imagedestroy</span><span style="color: #007700">(</span><span style="color: #0000BB">$aa</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">imagedestroy</span><span style="color: #007700">(</span><span style="color: #0000BB">$normal</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <div class="example-contents"><p>The above example will output something similar to:</p></div> <div class="mediaobject"> <div class="imageobject"> <img src="figures/image.imageantialias.png" /> </div> </div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <blockquote><p><b class="note">Note</b>: <span class="simpara">This function is only available ifPHP is compiled with the bundled version of the GD library.</span></p></blockquote> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.imagecreatetruecolor.html" class="function" rel="rdfs-seeAlso">imagecreatetruecolor()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div 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