POV-Ray : Newsgroups : povray.binaries.images : Just an experiment - 1 attachment : Re: Just an experiment - 1 attachment - 2 attachments Server Time
15 Nov 2024 20:17:04 EST (-0500)
  Re: Just an experiment - 1 attachment - 2 attachments  
From: Zio Pera
Date: 7 May 2003 07:47:10
Message: <Xns93748C5166DE9fizbanlombardiacomit@204.213.191.226>
"JC (Exether)" <exe### [at] club-internetfr> wrote in
news:3EB### [at] club-internetfr: 

> The image looks nice.
> But unfortunately I don't think you can do a real even distribution by
> putting your holes on parallels and meridians. Actually even 
> distribution of points on a sphere is not an easy task at all. But you
> can get a good approximation by using a electrostatic repulsion-like 
> algorithm starting with a more or less random distribution and step by
> step moving them to be at even distances. But it costs CPU, it's more 
> complex and inelegant (it's an approx), so ...
> 
> Cordialement,
> 
> JC

I've already done this ;)
You can see the results in my previous posting (Subj: placing point on a 
sphere, date Feb 18 2003) or here in small res attachments. The point are 
calculated by an iterative C program, using a electrostatic repulsion 
algorithm. You can also have the code, I've posted it on 
povray.binaries.utilities


This attempt on parallels and meridians is simpler, and done using only 
SDL, so can be used when a real even distribution is not needed.

While I write, I'm trying to do an animation of the image, rotating the 
sphere along the Y axis... If it's worth, I'll post on p.b.a


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Attachments:
Download 'geo2x.jpg' (11 KB) Download 'geo1x.jpg' (24 KB)

Preview of image 'geo2x.jpg'
geo2x.jpg

Preview of image 'geo1x.jpg'
geo1x.jpg


 

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