<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:wfw="http://wellformedweb.org/CommentAPI/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
	xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
	>

<channel>
	<title>Zach Archer Blog &#187; julia</title>
	<atom:link href="http://blog.zacharcher.com/tag/julia/feed/" rel="self" type="application/rss+xml" />
	<link>http://blog.zacharcher.com</link>
	<description>This blog is GO!</description>
	<lastBuildDate>Fri, 09 Jul 2010 23:02:45 +0000</lastBuildDate>
	<language>en</language>
	<sy:updatePeriod>hourly</sy:updatePeriod>
	<sy:updateFrequency>1</sy:updateFrequency>
	<generator>http://wordpress.org/?v=3.0</generator>
		<item>
		<title>Fractal Transform, made with Pixel Bender</title>
		<link>http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/</link>
		<comments>http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/#comments</comments>
		<pubDate>Mon, 29 Dec 2008 09:06:11 +0000</pubDate>
		<dc:creator>Zach</dc:creator>
				<category><![CDATA[Flash]]></category>
		<category><![CDATA[Graphics]]></category>
		<category><![CDATA[fractal]]></category>
		<category><![CDATA[julia]]></category>
		<category><![CDATA[pixel bender]]></category>

		<guid isPermaLink="false">http://blog.zacharcher.com/?p=79</guid>
		<description><![CDATA[I made a Pixel Bender filter that performs Julia Set transformations on images. It looks great when it animates, the colors morph and twist like mathematical slime. Try it (Flash Player 10 required): JuliaTile.swf Source code: julia_tile_src.zip. Pixel Bender code is in src/shader/. The default image is Seattle's Space Needle. You can upload custom images. [...]]]></description>
			<content:encoded><![CDATA[<p>I made a Pixel Bender filter that performs Julia Set transformations on images. It looks great when it animates, the colors morph and twist like mathematical slime. Try it (Flash Player 10 required): <a href="http://zacharcher.com/lab/20081229_julia_filter/JuliaTile.swf">JuliaTile.swf<br />
</a></p>
<p><a href="http://zacharcher.com/lab/20081229_julia_filter/JuliaTile.swf"><img class="alignnone" title="Julia Set sample" src="http://zacharcher.com/lab/20081229_julia_filter/julia_sample.png" alt="" width="357" height="393" /></a></p>
<p>Source code: <a href="http://zacharcher.com/lab/20081229_julia_filter/julia_tile_src.zip">julia_tile_src.zip</a>. Pixel Bender code is in <code>src/shader/</code>.<a href="http://zacharcher.com/lab/20081229_julia_filter/julia_tile_src.zip"><br />
</a></p>
<p>The default image is Seattle's Space Needle. You can upload custom images. Very large images may set your processor on fire.</p>
<p><span id="more-79"></span>Parameters: <strong>Iterations</strong> sets how many times the Julia formula is applied per pixel. The iteration increments appear smooth, not stepped, because the code tweens across the destination coordinates of the two nearest iterations. <strong>Complex X&amp;Y</strong> are the real &amp; imaginary values of the transform constant. <strong>Bias X&amp;Y</strong> is something I hacked in, it skews the coordinates in a linear way, becoming more intense with each iteration.</p>
<p>The <strong>Fill Types</strong> are as follows:</p>
<ul>
<li>0: Pixels out of range are transparent; no fill.</li>
<li>1: Repeats the nearest edge pixel.</li>
<li>2: Repeats the source image, mirroring every other copy to create a smooth transition.</li>
<li>3: Repeats the source image without mirroring.</li>
</ul>
<p>The filter needs more features before it's "done", hopefully it's still enjoyable. The Pixel Bender code took about 30 minutes to write; the Flex wrapper took much longer.</p>
<p>Despite its limited feature set, Pixel Bender is pretty cool. My only misgiving is that Pixel Bender's runtime performance is never as good as I hope. I have another filter in the works that mimics NTSC television artifacts, but the performance is abysmal. The code can still be optimized; stay tuned.</p>
<div class='bookmarkify'><a name='bookmarkify'></a><div class='linkbuttons'><a href='http://del.icio.us/post?url=http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/&amp;title=Fractal Transform, made with Pixel Bender' title='Save to del.icio.us' onclick='target="_blank";' rel='nofollow'><img src='http://blog.zacharcher.com/wp-content/plugins/bookmarkify/delicious.png' style='width:16px; height:16px;' alt='[del.icio.us] ' /></a> <a href='http://digg.com/submit?phase=2&amp;url=http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/&amp;title=Fractal Transform, made with Pixel Bender' title='Digg It!' onclick='target="_blank";' rel='nofollow'><img src='http://blog.zacharcher.com/wp-content/plugins/bookmarkify/digg.png' style='width:16px; height:16px;' alt='[Digg] ' /></a> <a href='http://reddit.com/submit?url=http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/&amp;title=Fractal Transform, made with Pixel Bender' title='Reddit' onclick='target="_blank";' rel='nofollow'><img src='http://blog.zacharcher.com/wp-content/plugins/bookmarkify/reddit.png' style='width:16px; height:16px;' alt='[Reddit] ' /></a> <a href='http://twitter.com/home/?status=Fractal Transform, made with Pixel Bender+http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/' title='Save to Twitter' onclick='target="_blank";' rel='nofollow'><img src='http://blog.zacharcher.com/wp-content/plugins/bookmarkify/twitter.png' style='width:16px; height:16px;' alt='[Twitter] ' /></a> <a href='http://www.feedburner.com/fb/a/emailFlare?itemTitle=Fractal Transform, made with Pixel Bender&amp;uri=http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/&amp;loc=en_US' title='Email this to a friend' onclick='target="_blank";' rel='nofollow'><img src='http://blog.zacharcher.com/wp-content/plugins/bookmarkify/email.png' style='width:16px; height:16px;' alt='[Email] ' /></a>  <a title='See more bookmark and sharing options...' href='http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/#bookmarkify' rel='nofollow'><small>More&nbsp;&raquo;</small></a></div></div>]]></content:encoded>
			<wfw:commentRss>http://blog.zacharcher.com/2008/12/29/fractal-transform-in-pixel-bender/feed/</wfw:commentRss>
		<slash:comments>4</slash:comments>
		</item>
	</channel>
</rss>
