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	<title>Smart-Page.net &#187; Lyapunov</title>
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	<description>C++ / C# / Actionscript / Py ... &#039;My God. It&#039;s full of stars!&#039;</description>
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		<title>Strange Attractor Finder and C4D/PY4D Particle Bench</title>
		<link>http://www.smart-page.net/blog/2009/09/15/strange-attractor-c4dpy4d-particle-bench/</link>
		<comments>http://www.smart-page.net/blog/2009/09/15/strange-attractor-c4dpy4d-particle-bench/#comments</comments>
		<pubDate>Tue, 15 Sep 2009 14:52:51 +0000</pubDate>
		<dc:creator>flashgordon</dc:creator>
				<category><![CDATA[3D]]></category>
		<category><![CDATA[AS3]]></category>
		<category><![CDATA[Flash]]></category>
		<category><![CDATA[General]]></category>
		<category><![CDATA[Python]]></category>
		<category><![CDATA[Bench]]></category>
		<category><![CDATA[C4D]]></category>
		<category><![CDATA[cinema 4D]]></category>
		<category><![CDATA[Generator]]></category>
		<category><![CDATA[Lyapunov]]></category>
		<category><![CDATA[Particles]]></category>
		<category><![CDATA[py4d]]></category>
		<category><![CDATA[Strange Attractor]]></category>
		<category><![CDATA[Strange Attractor Finder]]></category>

		<guid isPermaLink="false">http://www.smart-page.net/blog/?p=399</guid>
		<description><![CDATA[<a href="http://www.smart-page.net/blog/2009/09/15/strange-attractor-c4dpy4d-particle-bench/" title="Strange Attractor Finder and C4D/PY4D Particle Bench"><img src="http://www.smart-page.net/blog/wp-content/uploads/yapb_cache/sa_copy1.ekeje4pv6xw0gogg4skkwcogo.h9fw4mcunnwo4cowc8k4840k.th.jpeg" width="200" height="150" alt="Strange Attractor Finder and C4D/PY4D Particle Bench" style="float:left;padding:0 10px 10px 0;" ></a>Strange attractors are fractals that emerge at certain, sensitive parameters within the three-or more dimensional phase space.
They are are researched since the early 70s and strongly related to the chaos theory as they allow to watch the transition from chaos to order/geometry.
Good things first: see the result and try the chaotic attractor finder!


The 3D visualization [...]]]></description>
			<content:encoded><![CDATA[<a href="http://www.smart-page.net/blog/2009/09/15/strange-attractor-c4dpy4d-particle-bench/" title="Strange Attractor Finder and C4D/PY4D Particle Bench"><img src="http://www.smart-page.net/blog/wp-content/uploads/yapb_cache/sa_copy1.ekeje4pv6xw0gogg4skkwcogo.h9fw4mcunnwo4cowc8k4840k.th.jpeg" width="200" height="150" alt="Strange Attractor Finder and C4D/PY4D Particle Bench" style="float:left;padding:0 10px 10px 0;" ></a><p>Strange attractors are fractals that emerge at certain, sensitive parameters within the three-or more dimensional phase space.</p>
<p>They are are researched since the early 70s and strongly related to the chaos theory as they allow to watch the transition from chaos to order/geometry.</p>
<p><b>Good things first: <a href="http://www.vconverter.de/?file=strangeattractor" target="_blank">see the result</a> and try the <a href="http://www.smart-page.net/as3/sp_safinder/" target="_blank">chaotic attractor finder!</a></b></p>
<p><span id="more-399"></span></p>
<p><a href="http://www.smart-page.net/as3/sp_safinder/" target="_blank"><img class="alignnone size-full wp-image-417" title="sas" src="http://www.smart-page.net/blog/wp-content/uploads/2009/09/sas.jpg" alt="sas" width="596" height="157" /></a></p>
<p>The 3D visualization of a strange attractor is quite resource intensive as points race around the attractors on chaotic trajectories &#8211; so it needs many iterations or particles to see a shape emerge from that chaos.</p>
<p>There are already some <a href="http://www.unitzeroone.com/blog/2009/03/18/flash-10-massive-amounts-of-3d-particles-with-alchemy-source-included/" target="_blank">great flash experiments</a> so I turned to Cinema 4D and <a href="http://www.py4d.com/" target="_blank">PY4D</a> as an advanced renderer would easily allow to raytrace and shadow the results &#8211; and to calculate even more particles of course.</p>
<p><a href="http://www.smart-page.net/py4d/sp_strange/sp_strange_attractor_py4d.txt" target="_blank">This small PY4D script</a> creates a strange attractor that Dr. Clifford Pickover had published 1990.</p>
<p>Unfortunately I had to discover that the bottleneck at C4D wasn´t the rendering of vast amounts of vertices but the allocation of many particle objects.</p>
<p>I managed to render a maximum of 50.000 particles with the R11 before C4D outmaxed my systems ram (4GB).</p>
<p>Thats less than a sixth of what can be rendered realtime with flash.<br />
Admitted that comparison is unfair for many reasons, still&#8230; there is a point.</p>
<p>But with the new R11.5 release Maxon introduced render instances to C4D allowing now to calculate up to millions of particles &#8211; depending on the system.</p>
<p>Sadly I was limited to 300.000 points so I seeded the attractor parameters and rendered four transparent animations that could be combined to a 1.2 million particle video.</p>
<p>The preparation time for each frame was ~1min while PY4D took less than a second of that duration to perform five sinus/cosinus operations for each point.<br />
Rendering itself took about five seconds per frame (CPU:Q6600).<br />
Also its worth mentioning that the viewport can actually draw more particles that C4D is able to render.</p>
<p>It would be interesting to see how for example POVRay or Blender would perform when faced with this task.</p>
<p>If you are interested you can <a href="http://www.smart-page.net/py4d/sp_strange/sp_strange_attractor_py4d.c4d">download the szenefile</a> here.<br />
(Remember to activate render instances in the PShape node of the XPresso tag when using the R11.5).</p>
<p><span style="color: #ff9900;"><strong>Update:</strong></span></p>
<p>I already knew that 3D Studio Max and Softimage could handle several millions of particles but i was surprised to hear that Maya seams to have similar problems like C4D.<br />
I also gave Blender a shot and managed to preview and render over a million with ease.</p>
<p>When I learned that you can actually identify strange attractors using the  <a href="http://en.wikipedia.org/wiki/Lyapunov_exponent" target="_blank">Lyapunov exponent</a> and found <a href="http://technocosm.org/chaos/attr-part2.html" target="_blank">John Holder´s</a> programm &#8216;lyapdemo.c&#8217;, I took a few minutes to <a href="http://www.smart-page.net/as3/sp_safinder/" target="_blank">port it to AS3</a>.<br />
So I can find more fascinating attractors for further experiments (most likely with blender) and you can use it to generate parameters for the PY4D script aswell.<a href="http://technocosm.org/chaos/attr-part2.html" target="_blank"><br />
</a></p>
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