A few days ago (feb 9, i think) there was a thread about placing point
evenly on a sphere. 

Starting from the URL supplyed in that threat, and with a little C++
hacking, i've made a simple tool that generate a geode with an arbitrary
number of nodes. 

The nodes are placed using an electrostatic-repulsion algorithm; here
are an example with 120 points. 

If someone is interested, I'll post the C++ source code and a win32
executable on an appropriate group (maybe povray.binaries.utility ?).

Post a reply to this message

Attachments:
Download 'geo1.jpg' (65 KB)

Preview of image 'geo1.jpg'

I've written that system already with POV-SDL some
time ago, but never managed to clean the code and
make it available to public. The nice thing about it
is its in-between-steps. I've set up some animations
on my homepage, look under Animations.

But how did you process the points for the connections
with cylinders?

--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

> A few days ago (feb 9, i think) there was a thread about placing point
> evenly on a sphere.
>
> Starting from the URL supplyed in that threat, and with a little C++
> hacking, i've made a simple tool that generate a geode with an arbitrary
> number of nodes.
>
> The nodes are placed using an electrostatic-repulsion algorithm; here
> are an example with 120 points.
>
> If someone is interested, I'll post the C++ source code and a win32
> executable on an appropriate group (maybe povray.binaries.utility ?).
>
>
>

Post a reply to this message

"Zio Pera" <fiz### [at] lombardiacomit> wrote in message
news:Xns### [at] 204213191226...

> If someone is interested, I'll post the C++ source code and a win32
> executable on an appropriate group (maybe povray.binaries.utility ?).

Hi,

Yes, I am interested in the Win32 exe. Post it please.

All the best,

Andy Cocker

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"Tim Nikias" <tim### [at] gmxde> wrote in news:3e521bf8@news.povray.org:

> I've written that system already with POV-SDL some
> time ago, but never managed to clean the code and
> make it available to public. The nice thing about it
> is its in-between-steps. I've set up some animations
> on my homepage, look under Animations.
> 
> But how did you process the points for the connections
> with cylinders?
> 
> --


Well, once I've got the distributions, I calculate the minimum distance 
between two points, then I iterate through all the possible couple of 
points; if the distance between them is less than 1.5 the minimum distance, 
I connect the point with a cylinder.

I can't simply connect the couple that are *exactly* at the minimum 
distance, because the triangles are not exactly regular; that's occours 
only with platonic solids.

1.5 is the magic number that I've found working with all my examples.

By the way, I've made another little tool to generate a triangle mesh; here 
are an example. In this tool, I search triplet of point within 
1.5*minimum_distance to make a triangle.

The tools, and the source code, are posted on povray.binaries.utilities.

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Attachments:
Download 'geo2.jpg' (16 KB)

Preview of image 'geo2.jpg'

"Andrew Cocker" <mai### [at] andrewcockercouk> wrote in 
news:3e522283@news.povray.org:

> Hi,
> 
> Yes, I am interested in the Win32 exe. Post it please.
> 
> All the best,
> 
> Andy Cocker
> 
> 
> 

Here you are, on povray.binaries.utilities

Post a reply to this message

In article <Xns### [at] 204213191226>, Zio
Pera <fiz### [at] lombardiacomit> writes
>A few days ago (feb 9, i think) there was a thread about placing point
>evenly on a sphere. 
>
>Starting from the URL supplyed in that threat, and with a little C++
>hacking, i've made a simple tool that generate a geode with an arbitrary
>number of nodes. 
>
>The nodes are placed using an electrostatic-repulsion algorithm; here
>are an example with 120 points. 
>
>If someone is interested, I'll post the C++ source code and a win32
>executable on an appropriate group (maybe povray.binaries.utility ?). 

I would be interested in the source, and also if you could post the URL
again, I can't find the original thread here.

Cheers
-- 
David Parrott

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David Parrott <xam### [at] quayles1demoncouk> wrote in 
news:kbT4uLAe6hU+Iwt### [at] quayles1demoncouk:

> 
> I would be interested in the source, and also if you could post the URL
> again, I can't find the original thread here.
> 
> Cheers

Well, the original URL mentioned in the thread is 
http://www.math.niu.edu/~rusin/known-math/index/spheres.html

It seems that the posting in pbu was rejected; you can find
the tools I've made, with source code, on my scratch page:

http://www.geocities.com/ziopera_kolmogorov/index.htm

Post a reply to this message

"Zio Pera" <fiz### [at] lombardiacomit> wrote in message
news:Xns### [at] 204213191226...
>
> It seems that the posting in pbu was rejected; you can find

??

I picked up geode.zip up last night, Tuesday, from p.b.u.

I must find time to look at it now ;)

Alf

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Alf Peake wrote:
>"Zio Pera" <fiz### [at] lombardiacomit> wrote in message
>news:Xns### [at] 204213191226...
>>
>> It seems that the posting in pbu was rejected; you can find
>
>??
>
>I picked up geode.zip up last night, Tuesday, from p.b.u.
>
>I must find time to look at it now ;)
>
>Alf
>
same here ...
got it no problem from p.b.u.
and ditto on the time to look at it ;)

-ob-

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